http://www.firstlightastro.com/index.htmlAstronomy News and Viewsenritter777@gmail.comCopyright 2009 Mark Ritter2010-07-12T16:11:39-07:00 hourly 1 2000-01-01T12:00+00:00 Sun, 18 Jul 2010 16:13:04 -0700ritter777@gmail.comNone2010-07-12T16:11:39-07:00http://www.firstlightastro.com/skiesabove/files/20548822149f040194e2c196942548a8-151.php#unique-entry-id-151http://www.firstlightastro.com/skiesabove/files/20548822149f040194e2c196942548a8-151.php#unique-entry-id-151If you asked your friends what time of the year the Earth is closest to the sun, during winter or summer, I'd bet that most of them would say during summer. After all, we are hottest during the summertime, therefore we must be closer. Correct?

The reasoning seems airtight. But it presumes that our distance determines our seasons, and it neglects the fact that our southern hemispheric friends are experiencing a cold winter at the same time we're having our hot summer.

The fact is that for these last couple weeks we have been the farthest from the sun in our orbit. And it is in the dead of our winter that we are closest to the fires of our star. Huh?

As you know, every planet, comet, and space rock in our solar system orbits the sun. But despite the fact that planetary orbits are drawn as perfect circles in our textbooks, they are not.

But that's OK. We don't need a perfectly circular orbit. Slightly oblong - we call it "elliptical" in the Land of Science - is just fine. But here's the point: Since it is not a perfect circle, it follows there must be a time in an orbit when a planet is closer to the sun than at all other times, and another time when it is farthest.

And it is now, at the beginning of July, that we are at our farthest. This "farthest point" in an orbit around the sun has a name, aphelion. Our closest point to the sun happens in the first week of January. Then we are at perihelion.

Now a fair question is: Why aren't we freezing right now, being farther away? Well, the difference between our aphelion and our perihelion isn't that dramatic. Our orbit, although not a perfect circle, comes close. There is a difference of only a few million kilometers between the two. But we are so far out that a couple million klicks doesn't matter.

Here's an analogy: Suppose you are a hundred yards away from a bonfire. If you were to take a big step closer would you feel the temperature rise? How about a step farther away? Would you feel a lot colder? Probably not.

Same with the sun. Our tiny difference in aphelion and perihelion makes no traumatic change in climate over the year. It is our tilt that gives us our seasons. The important question is: Are we tilted towards the sun or away? We are tilted towards the sun now, hence we have summer.

Don't get me wrong! Any more elliptical, or an average distance any closer or farther from the sun means very bad times on Planet Earth. But as it stands now - from tilt to spin to distance - all is very, very good.

]]>ritter777@gmail.comNone2010-06-28T16:07:36-07:00http://www.firstlightastro.com/skiesabove/files/01adea49ef4c6410d9f6fbf342fa6207-150.php#unique-entry-id-150http://www.firstlightastro.com/skiesabove/files/01adea49ef4c6410d9f6fbf342fa6207-150.php#unique-entry-id-150Maria Mitchell was an American astronomer who died on this date in 1889. Now, normally this just might be a footnote in history, and for most people it is. Except for this: Maria Mitchell was a woman and she was an astronomer. Those two qualities in one person were something quite extraordinary over hundred years ago.

Maria's parents were Quakers in Nantucket, Massachusetts, and Quakers had this crazy notion for the time that children, both boys and girls, should be afforded equal education. Her father, William Mitchell, noticed his daughter was strong in the areas of math and astronomy and so encouraged her to pursue them. Go figure!

This love for learning and education persisted as she assisted her dad in his teaching and then took on the role of librarian in Nantucket. But even as a librarian, her passion for astronomy continued.

On the night of October 1, 1847, armed with telescope, Maria was on the roof of the Pacific National Bank on Main Street in Nantucket where her father then worked. The 29-year-old Maria scanned the northern skies and saw there a blurry object that she knew was not normally amongst those stars. Those of you who do any backyard astronomy know that when you see a blurry object in a part of the sky that you know has no blurry objects, that you have probably just found a comet.

And a comet it was.

This seemingly small discovery of "Miss Mitchell's Comet" had an extraordinary effect on her future. Just the next year the American Academy of Arts and Sciences voted her in as their first woman member. (There was not another woman voted in until 1943.) In 1850, the Association for the Advancement of Science voted her into their organization.

By 1865 she ended up, to no one's surprise, as an educator, taking on the position of Professor of Astronomy at the brand new Vassar College in New York State. There she not only taught, but studied the surface features of Jupiter and Saturn and practiced the new art of astrophotography.

She worked at Vassar for more than two decades, retiring only because of ill health. She died on 28 June 1889, at the age of 70, and was buried next to her beloved father.

Maria Mitchell's life can show us at least two things; that good parents can play a huge and wonderful role in shaping a child's future, and that the love and wonder of the skies ought not be limited by one's gender - the study of the heavens is for everyone.]]>ritter777@gmail.comNone2010-06-14T16:04:01-07:00http://www.firstlightastro.com/skiesabove/files/1fa03d224cff7fb5454d78c477ecd16c-149.php#unique-entry-id-149http://www.firstlightastro.com/skiesabove/files/1fa03d224cff7fb5454d78c477ecd16c-149.php#unique-entry-id-149Summer is finally here. Some of us are now planning out vacation routes. Others, for one reason or another, are just staying home this year. One way or another, wherever we go, near or far, we can always get away from it all by looking up.

Maybe this summer can be your summer of discovery, the one you've always wanted to make, but never "got around to." And there are all kinds of things in the summer night skies that are worthy of discovering.

One trip you can take is to go out and observe the planets. In the western skies after sunset you can watch Venus reach her highest point this month then slowly make her way towards the horizon as summer breezes by. If you have a telescope, these are good weeks to see Venus' phase changes, as well.

Both Saturn and Mars are headed for a late July rendezvous with Venus. They are both now in the southwest skies in the evening. You can observe them both over the next 7-8 weeks wander closer and closer towards Venus.

The constellations can be part of your tour plans, as well. You might commit to learning where the Big Guys are, such as Hercules or Sagittarius or Scorpius or Cygnus. Or challenge yourself to seek out and conquer the more obscure constellations, like Corona Borealis, Delphinus, or the 13th member of the zodiac - Ophiuchus. Maybe you can read their mythological stories, as well, some of which are quite the soap-opera-of-the-gods type of entertainment. (Google "constellations summer skies" for star charts.)

You can also take a random trip through the heavens with a small telescope or binoculars, scanning the skies, fortuitously picking out double stars or star clusters along the way. Or, just for the sake of challenge, you can obtain a star chart (easily gotten off the internet) and, using only the charts in front of you and the stars above, look for charted star clusters or doubles or nebulae.

For some, the most challenging find will be the Summer Milky Way. The artificially lit-up skies of our locale are making this more and more of a challenge every year. (We will cover this problem in depth in a future article.) The Milky Way, our galaxy's disk, can be seen coming out of the southern horizon and heading north in a great band of light representing untold thousands of stars.

Both skyandtelescope.com and astronomy.com have a load of reference guides and hints to help you get to know our summer dome. Commit to some sort of tour this year. It's inexpensive - and fun!
]]>ritter777@gmail.comNone2010-05-31T11:44:08-07:00http://www.firstlightastro.com/skiesabove/files/31fc83970788b29b5b76993a85ebadcf-148.php#unique-entry-id-148http://www.firstlightastro.com/skiesabove/files/31fc83970788b29b5b76993a85ebadcf-148.php#unique-entry-id-148Last time here we learned about the names of the first four planets from the sun, the terrestrials. Now we hit the Giants in the outer solar system, and a distant dwarf.

The "gas giants," Jupiter and Saturn, are the last of our planets observed by the ancients. (Neptune and Uranus have only "recently" been discovered.)

Jupiter is the Roman equivalent of the Greeks' Zeus, the leader of the club, the Big God on Campus. His name, derived from Latin and earlier languages, roughly translates to Father God, but probably more for his siring prowess than his paternal instincts. You can still see the "father" - Latin "pater" - in his name. Coincidentally, he was the father of Mars.

Many of us think that Jupiter (or Zeus) was the main guy and that most of the myths revolved around him. Not so. Did you know that in the pagan pantheon Jupiter had a dad? His name was Saturn. The stories involving Saturn and his brothers and sisters are rich and numerous, if not also contradictory and varied. You've probably heard of the Titans and Cyclops; they were a part of this rich mythological time.

One story involved Saturn and his own dad, with whom he did not have the best of relations, whom he ends up castrating! Saturn's father was God of the Sky, his mother was Mother Earth. Her name in the Greek myths was Gaia, his Ouranos; the Latin version of which is Uranus.

Uranus, the ice giant planet, was too dim to be seen by the ancients. It wasn't until 1781 that scientist William Herschel, with telescope, discovered it. Herschel wanted to honor King George III, his benefactor, and call the planet George. Others suggested Herschel. Thankfully, more reasonable minds prevailed and the planet was named Uranus. Now there was Mars, son of Jupiter, who was son of Saturn, who was son of Uranus. Son of a gun, that's works out nicely.

But what about Neptune? Discovered in 1846, it, too, went through a little naming controversy, with one proposed name being Le Verrier after one of its discoverers. But again, in keeping with tradition, the scientific community named the planet for a mythological figure, here a brother of Jupiter, god of sea and water, Neptune.

There is one more celestial body out there we should mention out of respect. Although no longer considered a planet, it is part of our planetary heritage. Discovered in 1930 by Clyde Tombaugh, the name Pluto was suggested by a little girl in England who knew her mythology and figured since the planet was probably cold as heck, that it should be named for the god of the underworld. And so it was named after Pluto, also a brother of Jupiter.

There are the Original Nine, complete. Until next time, clear skies!

]]>ritter777@gmail.comNone2010-05-17T11:42:15-07:00http://www.firstlightastro.com/skiesabove/files/2d33cd199f09b10d1a834c119da6e1f4-147.php#unique-entry-id-147http://www.firstlightastro.com/skiesabove/files/2d33cd199f09b10d1a834c119da6e1f4-147.php#unique-entry-id-147Part of a more complete understanding of the skies above involves knowing not just the names of objects up there, but how they got their names. Today we will look at the names of the first four planets, the earth-like planets. Next time we will hit the outer giants, and a dwarf planet called Pluto.

Of course, every culture has its names for the planets, but we will focus here on those handed down to us in the west from the Babylonians, Greeks, and Romans thousands of years ago.

The skies back then were sacred, the abodes of the gods, and a place reserved for the great stories of deity and heroes.

But the planets - the word itself comes from a Greek word meaning "wanderer" - weren't fixed in the skies as were the stars. They moved. They were something unique and set apart. Hence, for the most part, they are named for the Big Gods on Campus.

Let's start with Mercury. For millennia humans have noticed a little pin prick of light that hugs the sun, sometimes at sunrise, sometimes at sunset. This little guy would move noticeably through the skies not over months and years, but in days. It was quick, so what better god to represent it than the fleet-of-foot Roman messenger god, Mercury ("borrowed" from the Greeks' Hermes).

Venus, second from the sun, represents the only female deity of the lot. The Babylonians first named it after their goddess of love, Ishtar. The Greeks followed suit soon after, naming the planet after their goddess of love, Aphrodite. And of course the ever-borrowing Romans followed them both up by naming the planet after - you guessed it! - their goddess of love, Venus.

Mars' name may have been influenced by its color. Its light reddish hue may have typecast it into a violent role. The Greeks called it Ares, after their god of war. Later, the Romans, sometimes not the most creative people, gave us the name Mars after their god of war.

What about Earth? Well, until the Middle Ages our planet wasn't really a "planet" in the ancient sense of the word, i.e. a wanderer in the skies. Our word "Earth" is from the Old English word "eorthe," which meant the land or ground or soil, which it still means today when we say, "This is good earth for growing corn." Well, the term stuck around, going global around the 1400's to mean our whole planet.

Who is up next time? The big guys... and one tiny dwarf. ]]>ritter777@gmail.comNone2010-05-03T11:36:07-07:00http://www.firstlightastro.com/skiesabove/files/96ad812b58e23b13b2adf279116f93b0-146.php#unique-entry-id-146http://www.firstlightastro.com/skiesabove/files/96ad812b58e23b13b2adf279116f93b0-146.php#unique-entry-id-146In my class I have hanging from the ceiling on a string a pencil, parallel with the ground, with some magnets taped to it. The carefully ordered magnets force the pencil to point north. This homemade compass is a simple, but elegant, everyday display of our planet's magnetic field.

And what a field it is!

Our magnetic field reveals to us what is going on down below our feet, helps us find our way on the surface, and protects us from destruction above. How?

Through some complicated physics, it has been shown that a magnetic field can arise from a rotating, conducting fluid. Meaning, if a planet has a sphere of liquid iron down below the surface, the rotation of that planet can cause the liquid to throw a protective magnetic shield around the planet. The field is similar in shape to that taken by iron filings around a bar magnet, like we all saw in elementary school.

We believe that way down below, at the center of planet earth, we have an "inner core" made of very hot - but solid - iron and nickel. But surrounding that we have a molten, swirling "outer core" of liquid nickel and iron, perfect conditions for a magnetic field.

On our surface we can take advantage of this magnetic field with a compass, which has a magnetized pointer that lines up with our magnetic field and allows us to find magnetic north (which is not exactly true north, but close). This has allowed people for centuries to find their way around this planet, and has saved many a lost soul.

Way above us, our all-encompassing magnetic field interacts with pesky charged particles. So what? So this...

The sun bathes us in a wind of charged particles called - surprise - the solar winds. Composed of mainly protons and electrons, this wind travels at hundreds of miles per second.

But instead of those bothersome particles blasting into us and wreaking havoc on our atmosphere - especially on poor water vapor which it can strip from a planet - our magnetic field steps in and calmly says, "Wait a minute, here."

The laws of nature ensure that our magnetic field will deflect the charged wind around earth and by us, like a sailing ship forces the waters aside and around.

Some of the particles do manage to sneak in through the weaker areas, around the earth's poles. As they crash into the atmosphere they light up the skies in beautiful Northern and Southern Lights.

If you ever see the Lights, or just play with a child's compass, pause. You are witnessing the effects of a remarkable planetary phenomenon.]]>ritter777@gmail.comNone2010-04-19T17:44:21-07:00http://www.firstlightastro.com/skiesabove/files/9ff1e25f05a8e6714f77ba49036d36f3-145.php#unique-entry-id-145http://www.firstlightastro.com/skiesabove/files/9ff1e25f05a8e6714f77ba49036d36f3-145.php#unique-entry-id-145The Observatory on Palomar Mountain, our very own national monument and astronomical workhorse is offering tours to the public! If you haven't been there in a while, things have changed.

I remember first going up there with my family years ago and being greeted by... well, nothing much. We called it the Plexiglass Tour because our visit was pretty much nothing more than pressing our face up against a huge window in the visitor's room and trying to make out the Great Scope in the darkness. Being an astronomy enthusiast, it was anticlimactic to say the least.

But things have changed - a lot. Now there are tours which actually take one inside the venerable Dome. Here's what you can expect:

The tours start off at the big back door of the dome with a brief background of the historic building, then moves inside to the ground floor. There you are introduced to the great skeleton of the edifice which is built both to resist earthquakes and to support the hundreds of tons that the complex telescope weighs.

Now upstairs to the main observing floor. And there in front of you is the Behemoth; the famous Hale Telescope on the largest mount you will ever see - both of them works of engineering art. Here you will hear the basic functions of how the colossal telescope is used by astronomers to answer the great mysteries of the universe.

That is usually enough for a nerdy guy like me, but this tour includes a walk up to the inner catwalk of the dome to get the big picture of the whole show, if you can take it all in. But wait - there's more!

Now the tour takes you to the outside catwalk, a viewing pleasure not for the faint of heart. Outside one can get the full-360 view of the mountain and all the other telescopes on the hill. The catwalk itself, although completely safe, almost makes you feel like you are walking on air since it is made of metal mesh.

Come back on in now and all the way downstairs to the point where it all began an hour earlier.

The tours are every Saturday and Sunday from April until October: 11:30 AM, 1 PM and 2:30 PM. They run it on a first-come, first-served basis and the cost is $8. More info can be found here: www.astro.caltech.edu/palomar/tours.html

It is one fantastic day: an inexpensive time with family and friends, full of science and history, surrounded by the natural beauty of the mountain. ]]>ritter777@gmail.comNone2010-04-05T17:42:32-07:00http://www.firstlightastro.com/skiesabove/files/ffc42604e763f707590de2d8ebed9477-144.php#unique-entry-id-144http://www.firstlightastro.com/skiesabove/files/ffc42604e763f707590de2d8ebed9477-144.php#unique-entry-id-144There are four planets in the sky this month. Mars is above us in the early evening, Venus is setting in the west at this time while Saturn rises in the east. Jupiter is visible before sunrise in the east for readers who themselves rise before the sun. Let's have a quiz involving these heavenly bodies! (Warning: There may be more than one answer!)

Which of these heavenly bodies is made completely of gas?

Answer: None of these. Although Jupiter and Saturn are often referred to as "gas giants," this is a misnomer. They do have thick atmospheres to be sure, but deep down below the clouds we believe there is liquid, and way, way below that there might be a solid core!

Which show signs of being pounded by giant rocks from space?

Answer: Mars and Venus. Mars has craters - evidence of devastating impacts - all over the place. But Venus is covered with clouds. How can we tell she's been hit? We can use special instruments, instruments which use radar to see though those clouds to the surface, and there we see the craters - a lot of them. Jupiter and Saturn have been hit often, too, but their clouds swallow up the impactors and soon all traces of a hit are gone.

Which can be either a "morning star" or an "evening star"?

Answer: That's a tough one. Of course, Venus can be either. She shines so brightly that when one refers to the "morning star" or "evening star," it is almost always assumed that it is in reference to Venus. But there are others who refer to any of the bright planets, including Jupiter and Mars, which set with the sun or rise with it in the morning, as evening or morning stars. So, this month's evening star would definitely be Venus, the morning star would be Jupiter - for some.

Which will we never see above us at midnight?

Answer: Venus. Jupiter, Saturn and Mars are in orbits outside ours. Venus is on an inside track around the sun. Because of this orbital layout, Jupiter, Saturn, and Mars can be on the opposite side of Earth than the sun. So when the sun is directly below our feet at midnight, these planets can be directly above our heads. Not so Venus. Confined to be near the sun, we can see her only near the sun, either following our star at sunset or leading it at sunrise.

Until next time, clear skies!]]>ritter777@gmail.comNone2010-03-22T17:38:30-07:00http://www.firstlightastro.com/skiesabove/files/875385878efef6f020a3057e7d8d0f3e-143.php#unique-entry-id-143http://www.firstlightastro.com/skiesabove/files/875385878efef6f020a3057e7d8d0f3e-143.php#unique-entry-id-143It is always about this time of the year that my astronomy class takes on Planet Earth. We've studied the evolution of modern astronomy from the days it was no more than glorified astrology to the high science it is now. We've observed the cosmos out to the "edge," delved into how stars are born, live, and die, and investigated the strange world of dark matter and supermassive black holes.

This week, though, one of my students will inevitably say, "I thought this was astronomy. Why are we now studying Earth?"

On the surface it seems like a legitimate question. "Aren't we supposed to be studying what is above our heads, not what's below our feet? What does our atmosphere or plate tectonics or volcanoes or earthquakes have to do with astronomy?"

An immediate, cold and rational answer would be that Earth is part of the universe. We are studying the universe. Hence, the earth would be included in our studies.

But it goes deeper than that, I believe. We can study our planet for philosophical reasons.

Let me give an analogy. Some of us go to the zoo and are satisfied with merely seeing some animals, spending time with loved ones, then getting home. Some spend time at the zoo actually observing the animals; how they move, how they are put together, how diverse they are in some ways, and how similar in others. These people might even go to the zoo without family or friends, if only to satisfy their great curiosity about the living realm around them.

But there are a few of us who go to the zoo and, after observing the animals, see something deeper. These people see that we ourselves, we humans, are in some ways connected to these other critters, but in other ways we are profoundly different. We don't walk out thinking only about where we are going to eat. We don't walk out thinking only that those peacocks sure were beautiful.

We walk out thinking we sure are special. And I do not mean that in an arrogant way. There is something deeply distinct about us humans in just about every aspect of life on earth. But until we know enough about those other critters - and know ourselves - we won't be able to see the truth: We are unique.

So after months of studying the diverse characters in the universe, the stars and galaxies and the vast empty space between them, its unimaginable violence and extreme danger, we come home to earth to study our planet with all its plates and water and continents and climates.

And when we study our planet in detail, we realize how truly unique and beautiful our home is. We are special. We are blessed. We can look around the universe, then see ourselves and proclaim that this earth is good. No! Make that "very good."]]>ritter777@gmail.comNone2010-03-08T17:36:43-08:00http://www.firstlightastro.com/skiesabove/files/c166463263a74b3db7a2809b99f01dcc-142.php#unique-entry-id-142http://www.firstlightastro.com/skiesabove/files/c166463263a74b3db7a2809b99f01dcc-142.php#unique-entry-id-142Planet Round Up time! There are at least seven pesky planets moseying around up there. Let's go find them!

First let's track down and check off the planets that we will have the toughest time seeing due to that big bright plasma ball up there, namely, our sun.

You can just plain forget about seeing Neptune and Uranus. Both of those giant planets are on the opposite side of the sun and will not orbit around fast enough to see well anytime this month. Tiny Mercury is hiding behind the sun now, too.

There are two other star players near the sun now, as well. But they are not so close to our star that we cannot find them - if we know where to look.

Jupiter, because of our own speedy orbit, appears to be slipping closer to and behind the sun this month. Catch him now in the west after sunset; the Big Guy won't return until later in March in a new role as a "Morning Star."

Venus, that speedster, is whipping around the sun now at a good clip and is trying to pass Jupiter in the skies, going the other way, from our point of view. You will have a tough time seeing Venus this week since our hellish sister is still so close to the sun, but by next week she will pull away and be easy to spot.

Ready for a challenge? Go out next Sunday, the 14th, just 15 minutes after sunset and look towards where the sun has just set. There you will see two "stars." That would be Jupiter and Venus, a site which is pretty enough all by itself. If you look carefully just to the "right" of the two, you may see the faintest hint of the thinnest crescent moon. A thin crescent moon with a side of planets: what a combo!

So where is our other neighbor, our little buddy Mars? Mars, unlike Venus and Jupiter, is on the opposite side of the sky as the sun. So as the sun sets in the west, Mars is rising over in the east. It is relatively easy to see: It is pinkish, and a couple times brighter than any star near it.

Saturn is the only planet left. Like Mars, Saturn is on the same side of the sun as we. It will be rising in the 9 o'clock hour this week. Over the next weeks and months it will rise earlier and earlier, making it a better and better find as time go by.

However, because of unfortunate combinations of orbits and tilts, we are seeing the rings almost edge-on this year. That kind of takes away from their beauty. But hey, it's still Saturn, a handsome planet even with thinned-out rings.

Happy trails!]]>ritter777@gmail.comNone2010-02-22T21:32:14-08:00http://www.firstlightastro.com/skiesabove/files/b29505ba727d10c82c55c5017534704d-141.php#unique-entry-id-141http://www.firstlightastro.com/skiesabove/files/b29505ba727d10c82c55c5017534704d-141.php#unique-entry-id-141This week we mark the passing of one of the greats of astronomy. His is a name not well known outside of the discipline, but people who love the skies are indebted to him for his astonishing accomplishments.

It was this week in 1938 that George Ellery Hale died of heart problems at the age of 69. But the achievements he left behind, including one local work of art, have changed our view of the cosmos forever.

Although a legitimate astronomer in his own right - the sun was his specialty - it is what he built that made all the difference in the world. He was the man behind the construction of three of the biggest telescopes of the 20th century.

In 1897 he founded the Yerkes Telescope in Wisconsin, equipping it with a monstrous 40-inch lens. In the early 1900's he built the famed observatory on Mt Wilson above Los Angeles. There the Hooker Telescope, sporting its 100-inch mirror, reigned as the supreme telescope in the world until the building of our own "Cathedral of the Heavens," the Palomar Observatory which houses the 200-inch Hale Telescope.

Hale was not just trying to build bigger telescopes just for the sake of being bigger. In astronomy, size really does matter.

Our only physical connection with the heavens is light; that is where all our information is. We need light. With a larger lens or mirror on your telescope you can gather more light, and thus more information about planets and stars and galaxies and even the exotic stuff like dark matter. So what George Ellery Hale did was nothing less than helping us see the universe.

What kind of things were accomplished at his observatories? Here's a short list:

It was at Hale's observatories that astronomers discovered we were not in the center of the Milky Way, but over in the safer suburbs of the galaxy. Moreover, it was discovered that our galaxy was not alone, but just one of a seemingly infinite number of them.

Scientists using the Hale's scopes determined that stars are born, live, and die, and that their blown-out debris give us all the elements of the Periodic Table.

Astronomers using Hale's observatories discovered that we were an expanding universe which led to the belief that the universe indeed did have a beginning. And in observing vastly distant objects called quasars it was determined that our universe did not just have a beginning, and was not just expanding, but was enormous beyond comprehension.

It was Hale's rugged determination to build these observatories that led to these worldview changing discoveries.

Want to know more? His life has been portrayed in several books and in the recent PBS documentary, The Journey to Palomar. And of course you can yourself make a sort of pilgrimage to Palomar Mountain itself and see his last work of art, one that reigned supreme up until the 1990's when bigger telescopes were finally built.

Until next time, clear skies!]]>ritter777@gmail.comNone2010-02-08T21:58:59-08:00http://www.firstlightastro.com/skiesabove/files/749aef09f9246eb79cec32cd6bfe1a8c-140.php#unique-entry-id-140http://www.firstlightastro.com/skiesabove/files/749aef09f9246eb79cec32cd6bfe1a8c-140.php#unique-entry-id-140Planet Round Up time! There are at least seven pesky planets moseying around up there. Let's go find them!

First let's track down and check off the planets that we will have the toughest time seeing due to that big bright plasma ball up there, namely, our sun.

You can just plain forget about seeing Neptune and Uranus. Both of those giant planets are on the opposite side of the sun and will not orbit around fast enough to see well anytime this month. Tiny Mercury is hiding behind the sun now, too.

There are two other star players near the sun now, as well. But they are not so close to our star that we cannot find them - if we know where to look.

Jupiter, because of our own speedy orbit, appears to be slipping closer to and behind the sun this month. Catch him now in the west after sunset; the Big Guy won't return until later in March in a new role as a "Morning Star."

Venus, that speedster, is whipping around the sun now at a good clip and is trying to pass Jupiter in the skies, going the other way, from our point of view. You will have a tough time seeing Venus this week since our hellish sister is still so close to the sun, but by next week she will pull away and be easy to spot.

Ready for a challenge? Go out next Sunday, the 14th, just 15 minutes after sunset and look towards where the sun has just set. There you will see two "stars." That would be Jupiter and Venus, a site which is pretty enough all by itself. If you look carefully just to the "right" of the two, you may see the faintest hint of the thinnest crescent moon. A thin crescent moon with a side of planets: what a combo!

So where is our other neighbor, our little buddy Mars? Mars, unlike Venus and Jupiter, is on the opposite side of the sky as the sun. So as the sun sets in the west, Mars is rising over in the east. It is relatively easy to see: It is pinkish, and a couple times brighter than any star near it.

Saturn is the only planet left. Like Mars, Saturn is on the same side of the sun as we. It will be rising in the 9 o'clock hour this week. Over the next weeks and months it will rise earlier and earlier, making it a better and better find as time go by.

However, because of unfortunate combinations of orbits and tilts, we are seeing the rings almost edge-on this year. That kind of takes away from their beauty. But hey, it's still Saturn, a handsome planet even with thinned-out rings.

Happy trails!]]>ritter777@gmail.comNone2010-01-25T21:53:12-08:00http://www.firstlightastro.com/skiesabove/files/6a00920db63963718fa4309132f417e7-139.php#unique-entry-id-139http://www.firstlightastro.com/skiesabove/files/6a00920db63963718fa4309132f417e7-139.php#unique-entry-id-139When massive traumatic planetary events occur on Earth, specifically those which strike down thousands if not hundreds of thousands of humans in a fell swoop, people like myself feel compelled to defend the planet.

It's not any attempt to minimize the suffering and death that occur in places like Haiti or Indonesia; I would never do that. What happened in Haiti a couple weeks ago is a genuinely tragic historical phenomenon.

But the "culprit," namely planet earth, is designed in such a way that events like Haiti's earthquake have happened countless times before, they will happen again this year, and they will happen plenty more in our future. There is no surprise there.

I would argue, though, that the process which shakes our surface is the same process that makes this such a beautiful place to live.

You will recall that out planet has a thin, thin layer of solid rock - just miles thick - on top of gooey innards. This thin layer, our crust, is broken into a couple dozen plates which float about very slowly across the top of the planet.

As the plates slide into and by and away from each other, there is, of course, a whole lot of shaking going on. We in Southern California know well and first-hand what can happen when two tectonic plates scrape by each other.

The same thing happens when plates crash together head-on, or split apart. You may remember that although it was massive wave that killed all those people in the Indian Ocean tsunami in 2004, it started from a slipping of two plates.

But the movement of the plates is absolutely necessary.

The movement provides us with separated continents and high mountains and islands and oceans. With no uplifting forces our planet would have eroded down to a smooth sphere long ago and we would be completely covered in water. Plate tectonics have also been involved in the steady removal of carbon dioxide from the atmosphere over the eons, helping to insure we would not end up like our hellishly hot, carbon dioxide laden sister, Venus.

Earthquakes should not take us by surprise. In fact, if I may be so bold, I feel confident in predicting there will be massive earthquakes in the near future in places like Persia, Turkey, Indonesia, Oregon/Washington, and of course, our own Southern California. When? I have no idea; but they will occur.

Earthquakes, volcanoes, hurricanes, and floods are all by-products of the design of this awe-inspiring planet and we can live through them all if we are prepared. Tragically, our neighbors in Haiti were not. Will we be ready ourselves when it is our turn?]]>ritter777@gmail.comNone2010-01-11T19:33:45-08:00http://www.firstlightastro.com/skiesabove/files/fd2f803eab77eca7570bf76787684a8e-138.php#unique-entry-id-138http://www.firstlightastro.com/skiesabove/files/fd2f803eab77eca7570bf76787684a8e-138.php#unique-entry-id-138Now that 2009 is behind us, the official "Year of Astronomy" is over. But is that going to stop us here? Of course not. In fact, let's pick up where the Year of Astronomy started it all, with Galileo.

It was in 1609 that Galileo revolutionized astronomy with his upgraded, improved version of a recently created tool called the telescope. It was department store quality by today's standards, but it opened up a whole new realm for those of us who are fascinated by the skies. Now we could see deeper into the heavens and resolve objects we didn't even know existed. Subsequent discoveries helped change the worldview of the western world forever.

One of his discoveries took place 400 years ago this week, and featured an object in the sky you can see this evening for yourself. On 7 January 1610, he fixed his tiny telescope on Jupiter and around it found "three fixed stars, totally invisible by their smallness."

That was an important discovery in itself, but what made this historic was the observations he made over the following week when, quite to his surprise, those tiny "stars" - and another newly discovered one - had moved! (His drawings are shown here.)

It appeared that these tiny "stars" were really going around Jupiter, as if they might be tiny jovian moons. You have to understand the paradigm at the time which dictated that such a thing just could not happen. The cosmic philosophy then was based on Aristotle's teachings that everything in the universe went around the Earth.

So for someone to boldly announce that there were tiny objects orbiting something other than the Earth was novel, and somewhat dangerous, to say the least. It brought to the forefront the question that if little moons could orbit a bigger object, why couldn't the earth orbit the sun?

But this wasn't the end of Galileo's battering of the aristotelian wall. He also found "imperfections" on the Moon - mountains and "seas" - which flew against the established view that all heavenly objects were unblemished. He also observed spots on the sun, further evidence of imperfections.

Later in 1610, and very importantly, he observed that the set of phases that Venus went through - similar to the phases of the Moon - could only be explained if Venus went around the sun, and not around us.

The year 1610 was a big year in astronomy, a great big year. This week alone, 400 years ago, was a monumental week. You can relive it yourself by going out in the next day or two and scoping out Jupiter setting in the southwest after sunset. See if you can pick out the Galilean satellites yourself. Studying more deeply this art of astronomy may ultimately change your worldview, as well.]]>ritter777@gmail.comNone2009-12-28T11:02:25-08:00http://www.firstlightastro.com/skiesabove/files/a881adf0d61549f71530e17b6ddcbec0-137.php#unique-entry-id-137http://www.firstlightastro.com/skiesabove/files/a881adf0d61549f71530e17b6ddcbec0-137.php#unique-entry-id-137It is the end of another year, and if you have been a regular reader here I can assume that you have a least a passing interest in this fascinating discipline of astronomy. But have you done anything this year which took you beyond an occasional read? Have you put your faith into practice, so to speak? Resolve this year to do something!

Here are some suggestions I have been making for New Year's resolutions over the years now, but which are just as valid today.

Reading is a good place to start something new. There are a host of great books out there, most of which feature a trove of beautiful pictures. Check out amazon.com and search for astronomy books, or inquire at your local bookstore. Pick a book, buy it, and read it this year.

Can you afford to read only a few minutes a day? Then check out daily online sites like Astronomy Picture of the Day which not only has the obvious daily "picture," but also a whole mini-lesson of what the picture is all about. It's a great way for a person to learn a little bit at a time, and keep up-to-date. One way or another, can you commit to reading something astronomical this year?

How about observing? Maybe this year you can devote yourself to seeing that meteor shower you have been avoiding all your life. There are a half dozen good showers a year. Make one of them your own! Google "meteor shower calendar 2010" to see when they occur.

Another observing option would be to commit to memory a season's constellations. Winter has a beautiful set of stars, like Orion and Taurus, but so do all the other seasons, especially summer when it may be a little more comfortable to go out anyway.

You could also keep an eye on all the planets this year, to get to know how they wander the skies throughout the year. Another challenge would be to observe the Moon through an entire month, watching how it goes through an entire set of phases.

Observing would also, of course, include buying or borrowing a telescope. Get to know the basics of that great astronomical tool and then fall in love with the skies layers deeper than what you can see naked-eye.

In the mood for a day trip? You and your family or friends might consider this year a trip to Palomar Mountain for a visit to one of the world's premiere telescopes. Griffith Observatory in Los Angeles is a great place for astronomy lovers to visit, even if it has lost its night skies to the city of blinding lights.

Resolve this year to take more than just a passing interest in this grand pillar of the sciences. It will be so worth the effort. Have a great new year!]]>ritter777@gmail.comNone2009-12-14T09:51:42-08:00http://www.firstlightastro.com/skiesabove/files/ee0312b6b672ed5f077943a58c4bcb6a-136.php#unique-entry-id-136http://www.firstlightastro.com/skiesabove/files/ee0312b6b672ed5f077943a58c4bcb6a-136.php#unique-entry-id-136Well, it's finally here. No, I don't mean the end of the year, or the profoundly significant holiday season, or even the annual ritual of crass commercialism. What I mean is we are at the time of the year - in this next week - when that sun finally stops getting lower in the sky. The winter solstice is here; there is no need to worry that the sun might continue to sweep the sky ever lower in a slow, daily, downward descent into the horizon, never to rise again, plunging our land into everlasting darkness.

It is a gift we get every December holiday season, this stopping of the sun, or in its Latinized form, the "solstice." And most readers of this column will recall that it is the tilt our planet has with respect to the sun that allows these solstices to occur. At the moment we in the Northern Hemisphere are tilted far over and away from the sun so that the days are shortened and it is colder.

What about other planets? Does tilt play any important role there with their surface conditions? Not like it does here.
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Mercury is barely tilted at all. But it is so close to the sun that it has more important things to worry about, like days that are 800 degrees Fahrenheit and nights that plunge to -280.

Venus is slightly tilted with respect to the sun, but rotates so slowly and has such a inconceivably thick atmosphere, that tilt plays almost no role there, either.

Let's skip out to the giant planets. There, distance and spin rate and ultra thick atmospheres play such an overwhelmingly huge role that the tilts of those planets don't make much of a difference. And the Pluto-like bodies way, way out there get such a small amount of solar energy that, tilt or not, they are not comfortable places to live.

The only place outside of Earth where tilt might play a role worth considering is Mars, which is tilted much like Earth and experiences seasons like we do. The problem? There is no Moon to stabilize the planet, and over long periods of time Mars wobbles around like a flailing, failing top.

That leaves us. Our ideal tilt, along with our distance from the sun, our wobble-stabilizing Moon, our optimal atmosphere, our perfect combination of continents and oceans, and many other factors, allow us to enjoy these dark days of winter knowing we could really ask for nothing better. This list of design features allows us to experience the greatest amount of living space on a rocky body in the middle of space.

Observe for yourself the return of the sun in the next month or so as we slowly tilt back over. And remember, despite the cold and darkness now, spring is on its way.]]>ritter777@gmail.comNone2009-11-30T21:21:52-08:00http://www.firstlightastro.com/skiesabove/files/fa0393bd203ea3b10b176385d41b9d0c-135.php#unique-entry-id-135http://www.firstlightastro.com/skiesabove/files/fa0393bd203ea3b10b176385d41b9d0c-135.php#unique-entry-id-135Every year at this time, and throughout the winter months, there are some places in the sky that draw our attention like a flame lures moths. One attraction, of course, is the mighty constellation of Orion. Another might be Sirius, that intensely bright star to the east of him. But another inevitable eye-catcher is that little group of stars just to the "right" of Orion, the little cluster called the Pleiades.

Known to most people groups for millennia by many names, our name - the Pleiades - comes from the Greek myths about Atlas and his seven daughters. Hence, our alternate epithet for the cluster, The Seven Sisters.

It takes little imagination to see why, in astronomy, the Pleiades are called a "star cluster." But star cluster in astroland, specifically an "open" cluster like the Pleiades, implies more. It tells us that the stars there were born and raised at essentially the same time and place. The sisters in this family started forming about 100 million years ago.

And there are far more than the half dozen or so we can see with the naked eye, or even the dozens we can see through binoculars. There are over a thousand stars there, all traveling through the galaxy together like a flock of seagulls.

One particular bit of space trivia allows the Sisters to appear even more beautiful in photographic images taken of the area. At the moment they are traveling through a galactic cloud of dust and gas. When a star has a cloud around it, its light can be deflected in strange ways.

A star gives off all kinds of wavelengths, the whole rainbow of colors, just like our sun. But when that light passes through very small, microscopic bits of dust, the blue end of the spectrum gets scattered about quite well. Some of those scattered blue photons get thrown in our direction. So, the Pleiades looks like it's swimming through a veil of blue light. Coincidentally, this same effect is why our skies are blue; many of the blue photons of our sun's light get scattered in our atmosphere and - voilà! - blue skies.

One more thing about the Sisters: They are not the Little Dipper. The Little Dipper is an asterism over in Ursa Minor which includes the pole star, Polaris, aka the North Star.

Regardless of what you want to call it, take time this winter to grab a pair of binoculars and focus on the Pleiades, and find images online if you can. The Sisters are a sparkling bit of cosmic beauty.
]]>ritter777@gmail.comNone2009-11-16T20:44:56-08:00http://www.firstlightastro.com/skiesabove/files/78f574fec6d59015356170b32536a259-134.php#unique-entry-id-134http://www.firstlightastro.com/skiesabove/files/78f574fec6d59015356170b32536a259-134.php#unique-entry-id-134It's Thanksgiving time again. But with unemployment what it is, the economy not quite where we all hoped it might be, and all of us cutting corners, it might be a good idea this year to focus on the everyday things, in the heavens and on earth, for which we should be thankful. Let's take a look at some of these gifts as a friendly, gentle reminder that there really is a lot to be grateful for.

The air we breathe on this planet every moment of our life could not be a better mix. Most of it is composed of the almost inert gas, nitrogen. Only about 20% of it is life-giving oxygen, which is exactly how much we need for a beautiful life on this orb. Much more and any fires on the planet flame out of control in a heartbeat, any less and complex life like our own slows or stops.

There is just enough carbon dioxide - less than a percent - to keep the plants alive and yet still act as a warm blanket on the planet. And the amount of water vapor is just enough to give us our miraculous water cycle. It's not too much so as too heat us all up since water vapor is a greenhouse gas like carbon dioxide, nor is it so paltry as to parch the planet into a desert wasteland.

Our perfect surface is such a collection of wonders it would take a book to write of all its amazing characteristics. Suffice it to say now that our continents, seas, plate tectonics, mountains, volcanoes, quantity of land and oceans - everything under our feet - are all made to order for a pleasant time on this rocky planet. There is not a better combination of air, sea, and land that we know of. And we have it! Next time you look around at the beauty of nature you can bet it is probably designed to perfection and could not be otherwise.

But don't stop at our planet for things to be thankful for. Above our heads are the sun and moon. Our sun, that great giver of heat and light, is not your average star. Most stars, by far, are smaller, less energetic wimpy stars not well-suited to provide for a planet like ours. Many stars are bigger and spew out far more lethal doses of radiation than our star could dream of.

The moon, our own solitary satellite, keeps our planet balanced on its axis and holds the tides in perfect check. Moreover, both the sun and moon are at the just-right distances to do their work to perfection.

These are just a few of the hundreds of everyday things around us that we have been genuinely blessed with, but which we often take for granted. And these glorious stalwarts are above and beyond any trials that our present state of things can throw us. Be thankful!]]>ritter777@gmail.comNone2009-11-02T22:00:04-08:00http://www.firstlightastro.com/skiesabove/files/365258dffe4bd001f32783e6b507db05-133.php#unique-entry-id-133http://www.firstlightastro.com/skiesabove/files/365258dffe4bd001f32783e6b507db05-133.php#unique-entry-id-133Recently a new, monstrously big ring was found around Saturn. That was big news in itself. But it raised a legitimate follow-up question: How could astronomers have missed it all these years? Are they blind? Well, yes, in a way they are.

We've known about those other, more famous rings around Saturn ever since Galileo and subsequent astronomers trained their telescopes towards our sixth planet. Even a cheap department store telescope can make out those beauties. But we were all using scopes that capture and focus photons of visible light. Those are the only photons we can detect with our eyes. There are many - I mean many - more kinds of photons out there.

We have all at least heard about gamma rays, X-rays, ultraviolet, infrared, and radio waves. They, too, are all composed of photons, the same tiny bundles of energy that make up visible light. But whereas our eyes have been designed to react to the photons of visible light, we are literally blind to all the others.

For the record, gamma, X-rays, and ultraviolet from space pack more energy than the visible light we receive and they are almost all stopped by our savior of an atmosphere. On the other hand, infrared and radio waves are all wimps as far as energy is concerned. The atmosphere stops almost but not all of those photons. All of the visible wavelengths, however, can make it through.

In order to "see" photons that do not make it through the atmosphere we have to send special telescopes above the atmosphere, into orbit. There the full spectrum of photons can be seen if our instruments, our "eyes," are properly designed to pick them up. That's why we have X-ray and ultraviolet and infrared telescopes up there now - to complete the full picture of what is going on out there.

I'll bet you can guess why we could not see the new giant ring until now. It is because we literally cannot see it from here. The Saturnian rings we all know and love are made of big chunks of ice and they reflect the sun's visible light magnificently. But this new mega-ring is made of a thin wisp of tiny dust particles. They only give off just the tiniest amount of infrared radiation.

Astronomers, for reasons beyond the scope of this article, had suspected the big ring to be there. But they didn't find it until they made visible that which was invisible by training the infrared space telescope, Spitzer, on where they thought the ring should be. And behold, it was there.

Modern-day technology is making it possible for us to discover the deeper beauties of the cosmos previously unseen. This is a new Golden Age of astronomy.]]>ritter777@gmail.comNone2009-10-19T20:41:16-07:00http://www.firstlightastro.com/skiesabove/files/9d2e78cd349798f4f829ab45bb8a84aa-132.php#unique-entry-id-132http://www.firstlightastro.com/skiesabove/files/9d2e78cd349798f4f829ab45bb8a84aa-132.php#unique-entry-id-132This week in history - long ago in the year 2137 BC - the earliest known solar eclipse recorded by humans took place. Of course, solar eclipses had been a mainstay on planet Earth for b-zillions of years before that; this one was the first recorded.

But it wasn't recorded by ancient Europeans, and many of us might first guess. This event is found in a book called Classic of History, a Chinese book.

Not many of us are aware of the fact that other people groups outside of the west were heavily engaged in astronomy for eons. The Chinese were one of those people.

One of the main purposes for their observations - the same purpose for a lot of people - was to keep time, of course. Knowing when to plant and reap, and the ability to plan important annual events are important human activities. And the Chinese, like many people, studied the stars not just for telling time but for astrological purposes, for divining what might be coming up in the near future for whomever was in power at the time.

The Chinese contributed a lot to astronomy over the millennia. Centuries before Christ, Chinese astronomers were working out how to predict solar and lunar eclipses. And for thousands of years the Chinese have been cataloging the skies with elaborate star charts and collections of constellations.

While Europe was wallowing about in astronomy before and during the Middle Ages, contributing next to nothing, the Chinese were going strong. As just one example, it was they who saw and recorded a great heavenly event in the year 1054, somehow missed in Europe.

A Chinese document records this: "In the 1st year of the period Chih-ho, the 5th moon, the day chi-ch'ou, a guest star appeared... After more than a year it gradually became invisible..."

It turns out this "guest star" was nothing less than a supernova, the death of a giant star. The faint remnants of the explosion can still be seen in a backyard telescope as the Crab Nebula in Taurus.

One of the oldest observatories in the world was built in Beijing in the 15th century as Europe was beginning to awake from slumber. Built before the invention of the telescope, it sported the latest in observational equipment, including an armillary, a quadrant, and a theodolite.

The contributions of the Chinese are many and could never be satisfactorily covered here. Were the Chinese perfect in their predictions and theories and overall views of the cosmos? Of course not. Like the Arabs, and later, the Europeans, there was plenty of contribution, but also a fair share of miscalculation and misinterpretation. But they were on the A-list of astronomical contributors for literally millennia.]]>ritter777@gmail.comNone2009-10-05T20:39:39-07:00http://www.firstlightastro.com/skiesabove/files/1de60b42d2776ab59e08b90b0e43aa28-131.php#unique-entry-id-131http://www.firstlightastro.com/skiesabove/files/1de60b42d2776ab59e08b90b0e43aa28-131.php#unique-entry-id-131Ever look up in the evening skies just staring at the constellations, and suddenly notice a tiny illuminated dot floating gently across the expanse only to vanish into nowhere seconds later? That may have been the kin of an object launched into space over 50 years ago, a manmade satellite called Sputnik.

It was 52 years ago this week that the Soviet Union surprised us all by launching the first artificial satellite into orbit around our planet. Just a faint, almost invisible speck in the night sky, it collected data on the atmosphere and launched something of its own, namely the Space Race which ultimately led to our landing on the Moon.

Presently there are literally thousands of tiny manmade objects floating around up there. But doing what exactly? And how do we see one in action?

Satellites are used for a multitude of things. We addicts of Google Earth know that some satellites are up there taking a lot of high resolution, close up and personal pictures of our planet. For some, too personal. And people with GPS devices in their cell phones absolutely depend on satellites to get around.

Speaking of cell phones, there are also instruments in orbit for phone communications, and television, and radio.

Scientists use special instruments onboard satellites to see parts of the electromagnetic spectrum we cannot see. For example, with infrared detectors we can "see" the temperatures of landforms and ocean surfaces.

And of course, there are satellites not looking down on us, but looking up, out into the universe, like the legendary Hubble Space Telescope.

If you have never seen one with the naked eye, here's how.

After the sun sets, when the sky is finally dark enough to see a lot of stars, just go out in your yard, lay down and look up. That's all there is to it. Occasionally you may see a tiny fleck of light moving slowly but deliberately across the starry sphere. You will not see the red and green lights of an airplane, just that white dot.

Why early in the evening? Because it is then that the sun's light is gone for us, but not for a shiny satellite a couple hundred miles above Earth. They continue to reflect the light long after we on the surface are in the dark.

In fact, you may notice a satellite vanishing suddenly, before it gets anywhere near the horizon. That's because it is orbiting into the Earth's giant shadow. Unable to reflect the light of the sun, it fades to black.

Don't expect to see Sputnik up there. It burned up on reentry just months after its famous launch. Such is the eventual fate for most satellites.

Until next time, clear skies!]]>ritter777@gmail.comNone2009-09-21T20:38:19-07:00http://www.firstlightastro.com/skiesabove/files/96cc0ffb145b0c2494b8ae7695f088c0-130.php#unique-entry-id-130http://www.firstlightastro.com/skiesabove/files/96cc0ffb145b0c2494b8ae7695f088c0-130.php#unique-entry-id-130This week every year we celebrate the first day of fall, the autumnal equinox. We are headed for winter, summer is behind us (a hard sell here in Southern California, to be sure). But there is one historical event that annually gets overshadowed by this equinox business - the unique discovery of Neptune. Let's go there today.

For thousands of years, there were the Big Five planets above us: Mercury, Venus, Mars, Jupiter, and Saturn. Then, in 1781, Sir William Hershel discovered the next planet out, Uranus, while merely gazing through his telescope. Lucky guy.

But it wasn't until decades later, in 1846, that the next planet out was officially discovered. Why then, and how?

Planets way the heck out there are in no hurry to go around the sun. They do not race around in a fit like Mercury and Venus. And the farther out they are the slower they go. So, an untrained eye with no star charts with which to make comparisons will see those faint dots as nothing more than stars, not knowing they are indeed planets.

Once star charts and telescopes and mathematics became more refined in the 1800's, the odds of finding other, more distant planets shot up. And this is what happened with our remote neighbor, Neptune.

In the 1840's two men, a British astronomer named John Couch Adams, and a French one, Urbain Le Verrier, were independently perplexed by the odd movement of Uranus. Instead of moving slowly and steadily through the sky, records showed the planet speeding up for years, then slowing down.

Both men were convinced that this movement was no mistake in the calculations, that there had to be a distant planet, yet unseen, that was pulling and pushing on Uranus as it went by. The race was on to find it - but not by looking up, rather by doing the math. Using Newton's Laws of Motion on Uranus' strange movements one could narrow down where the culprit might be.

To make a really long - and fascinating - history lesson short, Le Verrier was the first of the two to not only publicly announce his mathematical findings, but also first to get someone with a telescope, namely Johann Galle at the Berlin Observatory, to go look for it. Galle received Le Verrier's correspondence with the coordinates, and on that very night, 23 Septemeber 1846, he and his assistant looked up and found Neptune, within one degree of where Le Verrier had predicted it to be.

It was a great triumph, not only in the finding of a planet, but of Newton's laws which were used to find it. Astronomy had taken a major step forward.]]>ritter777@gmail.comNone2005-01-15T11:50:59-08:00http://www.firstlightastro.com/skiesabove/files/36c17127f393c1bc3c26836c558d5402-129.php#unique-entry-id-129http://www.firstlightastro.com/skiesabove/files/36c17127f393c1bc3c26836c558d5402-129.php#unique-entry-id-129How can some scientists dare to declare planet Earth a near perfect, paradisiacal place for life when events such as last month's earthquake and tsunami kill hundreds of thousands and leave millions orphaned or widowed or homeless? Surely this epic event is clear evidence to us all that there is plenty to be questioned regarding this home of ours. Someone messed up somewhere.

It isn’t easy to try and portray this planet as a perfect home while watching the horrible images of bodies including women and children washing up on beaches in Sri Lanka, or entire communities in Sumatra just recently buzzing with life now completely swept off the map.

But things could be worse – a lot worse. And things could be better – a lot better - if we all get our act together.

This planet of ours has this extremely unique make-up. We have an oversized, hot, molten center enveloped by an extra-thin crust. Both of these are amazingly well composed for life on this third planet out from the sun. Their co-existence means that life can thrive here, but with some risk.

The best and latest theory elucidating how our planet got to be the way it is involves an amazing collision over 4.5 billion years ago.

It was then, we believe, that a Mars-sized object struck a very young and then smaller Earth with a glancing but devastating and well-timed blow. In fact, had the colliding body passed through an hour sooner or later only an uneventful near-miss would have occurred. But the collision happened, and it was magnificent.

It cleared away a horribly thick and deadly atmosphere, shredded away most of our crust much of which went into the formation of our Moon, and added an extra heaping helping of hot radioactive core material into the newly rearranged Earth.

How can a thinner crust and hotter inner parts help form a planet fit for life? Allow me a short order explanation of plate tectonics.

Our now thin crust resides, but certainly does not rest, upon a layer of molten, thick material below. How thin is it? Imagine an apple cut in half. The skin on the apple is about how thick our crust is compared to rest of the planet. It is very thin.

Being this thin, it is easily broken into many plates, like the broken eggshell still on an “unpeeled” hardboiled egg. Some sections are enormous, like the Pacific plate we here live on. Some are not so expansive, like the Burma microplate involved in December’s earthquake.

But they ride and they ride and they ride, relentlessly. All over the planet the plates slowly but surely ride along the slow-moving hot gooey mantle below, speeding along at just inches a year.

The plates can slide by each other like here at the San Andreas Fault. They can separate from each other, like in the horn of Africa. Or they can plunge into and below each other as they do in Indonesia and Japan and South America.

Their slow but unsteady movements lift great mountains and continents, help form hills and valleys and island chains, recycle life-giving minerals and gases. There is nary a geographical feature on the entire globe unaffected by the mighty tectonics. They make this planet what it is.

But if we had a thinner, weaker crust, this place would be the proverbial hell on earth. Imagine massive earthquakes all the time. Imagine volcanoes everywhere spewing endlessly their choking gases. Imagine being inundated with new lava flows all over, all the time.

If our crust were thicker and our innards cooler, we would have no plate tectonics. If this were to happen now, erosion would sheer down great mountains and hills and fill valleys until we were essentially flattened into a water-covered planet, a water world.

The big picture here is that the crust and guts of our planet just as they are now, both of which undeniably combine to give us the occasional devastating and deadly earthquake and tsunami, are also the foundation of all the things we find beautiful about this planet.

And fair warning to us all: It will happen again. Movement is necessary. We just have to learn how to live with it. And it can be done.

What is especially tragic about the December tsunami is that we humans might have saved a lot of those lost lives. How?
Of all the planets in the universe we know our home the best. We know that shifting oceanic plates and undersea landslides and above-water coastal landslides trigger tsunamis. We know they take a certain time to reach a destination.

Moreover, we know now how to communicate on a global scale. If there had been a warning system set up around the Bay of Bengal, as there is in the Pacific basin, many geologists believe hundreds of thousands of people might have been warned early enough that they literally could have walked away before the walls of water swept in.

Perhaps the best thing to come of such “natural disasters” on our planet is the way it transforms many of us into unselfish, caring folk. The outpouring of help and prayer and support from all over the world for complete strangers was and is genuinely moving. Maybe we can’t bring a man’s wife and baby boy back to life, but we can help rebuild his home and comfort him while he grieves.

Yes, we live on the best imaginable planet, but even here things don’t always go according to our plans. But we can help each other through these distressing times and maybe make the planet even better for it.]]>ritter777@gmail.comNone2005-01-29T11:49:14-08:00http://www.firstlightastro.com/skiesabove/files/a9000f8076bf1e6b271016bf5e87ebdd-128.php#unique-entry-id-128http://www.firstlightastro.com/skiesabove/files/a9000f8076bf1e6b271016bf5e87ebdd-128.php#unique-entry-id-128One of the most disappointing times for a newbie backyard astronomer comes when he or she looks for the first time through a brand new telescope and sees pretty much nothing. Well, nothing like what one sees on the covers of Sky and Telescope or Astronomy magazine or on websites like Astronomy Picture of the Day.

All those amazing images that have been pouring into the public mainstream for decades - grand and colorful spiral galaxies, kaleidoscopic nebulae, far-flung remnants of supernovae - are seemingly nowhere to be found.

Why is that, though? Why is it that when one looks, for example, in the astronomy journals at images of our sister galaxy, Andromeda, that the rich detailed blue spiral arms and central yellow fireworks come to life, but using our own eyes through even a good amateur telescope we see nothing much more than a grayish-green faint celestial fuzzball?

It’s a question of design and engineering.

Our eyes have been designed for life on a sunny planet. They are amazing works of art, able to capture photons of energy and translate them into electrical messages for the brain where those messages are turned into images.

But our eyeballs are inefficient in the best way. They are actually able to capture and process less than one in a thousand photons that make it in. Which is great, if you think about it.

If our eyes could suddenly process more photons, like one of a hundred or one of ten, all around us would seem intensely bright. We’d need some sort of filters to reduce the photon count.

Not capturing a lot of photons is not the only “problem.” Our eyes also don’t store photons to make the images we see.
Say some lucky photons enter the eye and react with the chemicals in the retina, the layer at the back of our eyes. These chemicals send their message to the brain but then “reset” for the next photon strikes.

This resetting allows continuous and successive images to be made and translated quickly so we can get constant and accurate updates from the outside world. Without this chemical process the entire world would seem more of a blur than it is already.

Try staring at something for a minute. Then close your eyes and see the image still there quickly fading away. Those chemicals are resetting; the image is soon gone.

Those beautiful space images we see are processed differently. Nowadays nearly all telescopes have charged couple devices (CCD) hooked up to them that act sort of like an artificial retina for astronomers. But these “retinas” work a little differently than human retinas.

First, they can capture and use more than half the photons that strike them! That is great efficiency.

Moreover, in CCDs the energy from the incoming photons can be stored. Heavenly objects appear very dim and fuzzy to our eyes because we can’t get enough photons to make a discernible image. But in one of these fancy cameras the energy from photons can build up over time until an image can finally be seen.

Some of the great images we have now are a result of minutes to hours of exposure to a single heavenly object. Some of the Hubble images of the faintest, most distant galaxies out there required over 30 hours of exposure! We’d never see those staring through a telescope ourselves.

And of course the images nowadays can be digitally manipulated to bring out colors and different textures and hues, things we are unable to do with our eyes.

On top of that some telescopes can “see” in wavelengths we cannot, such as infrared, ultraviolet, and X-ray.

Modern technology has allowed us to see incredible wonders of the skies in breathless detail, to be sure. But it doesn’t beat a walk out on a clear moonless night where most of us can - with our very own eyes - observe and absorb the awesome glories of the starry heavens.]]>ritter777@gmail.comNone2005-02-17T11:29:45-08:00http://www.firstlightastro.com/skiesabove/files/48f14fb54ca979b9a2572d07b16e3d1c-127.php#unique-entry-id-127http://www.firstlightastro.com/skiesabove/files/48f14fb54ca979b9a2572d07b16e3d1c-127.php#unique-entry-id-127Astronomy is like any other discipline, one with its own unique language and special heroes. And like the other disciplines many of these words and names get twisted about or misunderstood or are just plain hard to say. Here are only a few of the many examples I’ve picked up over years of teaching this divine discipline.

The term “astronomy” itself is one that is often misunderstood. When telling someone that I teach astronomy I often get a response that goes something like, “Oh, and what sign are you?” or “Do you know how to do horoscopes?” I have to explain then, in the nicest way of course, that what I teach is the science of astronomy, the study of the heavens, not astrology, its pseudoscientific etymological cousin.

When I tell my class that the next chapter we’ll be looking at is about cosmology, there is always the one well meaning, if not well read, student who exclaims something like, “What do make-up and lipstick got to do with stars?” Once I come to, I explain - in the nicest way, of course - that cosmology is the study of the entire universe from birth to impending death. It is not cosmetology, the study of cosmetics and their many interesting uses.

There are plenty of candy references I get to put up with, too. Besides the obvious planetary namesake that is the Mars bar, which recently went down the Street of Discontinued Candies - but which you can still get on eBay! - there is the astronomically christened Milky Way bar.

Recently it has been discovered that our galaxy, the real Milky Way, has a bar-shaped thicket of stars through its center. Our home is classified as a “barred spiral galaxy.” But don’t make the mistake of asking what the bar in the Milky Way is made of unless you want to hear the quirky answer, “Fluffy milk chocolate?” followed by some goofy laughter.

And, yes, there really is a type of cosmic phenomenon called a Starburst. And no, it is not composed of a multi-colored assortment of chewy fruit-flavored candy. It is a place of intense starbirth that can light up entire areas of galaxies.
Then there is the stockpile of singular names of astronomers past and present. I can lose a class for a couple minutes by just mentioning or trying to pronounce some of these names.

For example, Annie Jump Cannon is not a complete, but ungrammatical sentence about a woman leaping over a large cylindrical weapon. It is the real name of a very famous pioneering woman astronomer who was first to classify stars – over a half million of them - back in the early 20th century.

Other tongue-twisting topliners are Tycho Brahe, the great pretelescopic Danish observer; Karl Schwarzschild, a pioneer in the field of black holes; the extraordinarily eccentric Fritz Zwicky out of Caltech, one of the first astronomers to consider the now vital tool of gravitational lensing; Enjar Hertzsprung, another Danish astronomer who, with another astronomer by the relatively lackluster name of Henry Russell, gave us the most famous star diagram in astronomy.

In my opinion, though, the king of all names unique, and the moniker that offers a great chance for me to embarrass myself in front of my class, belongs to Subrahmanyan Chandrasekhar (pictured here). He was the world-class astronomer who helped define the mass limits of dead stars called white dwarfs. Mercifully for me, everyone called him Chandra for short. The Chandra X-ray Observatory, a cutting-edge tool for discovering the invisible universe, was named for him.

And, of course, even astronomy has its share of wordplay in the form of off-color double entendres. But I won’t foul this column with any of them except to ask you – in the nicest way, of course - to pronounce the seventh planet out, Uranus, with the accent on the first syllable, something like “YOUR-un-us.” If we all pronounced it that way, astronomy instructors could trade in hours of snickers for quality learning time.]]>ritter777@gmail.comNone2005-02-27T11:26:59-08:00http://www.firstlightastro.com/skiesabove/files/ce4f18c82c8c3d8f335b6dfc85af794a-126.php#unique-entry-id-126http://www.firstlightastro.com/skiesabove/files/ce4f18c82c8c3d8f335b6dfc85af794a-126.php#unique-entry-id-126I just about missed it. Winter nearly whisked by without a mention here of some of the wonders of the southern hibernal sky.

That was a close one.

Now, here’s the lowdown on what’s up in those glorious skies at the end of this cold and very wet month of February.

Let’s assume the best, that in the next couple nights we will have cloudless skies. The nearly three-week-old moon doesn’t rise until late evening so star gazing and planet seeking should be very nice.

And let’s use Orion as our wayfinder for our mini-adventure. You’ll find our hunting friend in the southwest skies, that great stellar quadrangle cut through by his famous belt.

At his “top left” shoulder there’s the famous red giant star, Betelgeuse. “Giant” is the right description for this dying star since he is over 600 times bigger than our sun. Put him where our sun is and he’d swallow all the planets out to and beyond Mars.

Opposite Betelgeuse, to the lower right, is bright blue Rigel. Both Betelgeuse and Rigel each pour out more energy than 50,000 suns. That’s why they can abide at their great distances of hundreds of light years – thousands of trillions of miles - and still appear as bright as they are.

But the energy leader of the Orion clan is that middle star in the belt. There lies Alnilam, a star that spews more than 112,000 suns worth of energy. It’s a fiercely violent star but is dimmer than the other stars in the great family because of its distance – more than 1350 light years from earth.

A quick trip through Orion would be incomplete without at least a mention of the most famous star nursery in the sky, the Orion Nebula.

Located just below the Belt, here are dozens and dozens of stars being formed in a luminous cloud of dust and gas. But, amazingly, only one star is lighting up the entire cloud, a bright O-type star in a tiny cluster of four named the Trapezium Cluster. One can see both the Nebula and the four tiny Trapezium through even inexpensive backyard scopes.

Closer - much closer - to Earth is the intensely bright star almost due south this evening and a little to the east of Orion. That is Sirius in Canis Major. This beauty is not so bright because it’s so big, but because it is so close. A mere stone’s throw 8.6 light years away, it is the closest star we can see this far north, besides the sun of course. (In case you’re wondering, southern folks can see the Proxima and Alpha Centauri pair, the closest stars to Earth overall.)

Now our next stop on the tour is a planet, but it will take a little sleight of hand to get there. Imagine a line made from the top two stars of Orion - from Bellatrix at the upper right through Betelgeuse at the upper left. Holding your arm out and spanning your hand, imagine a line extending out to the left from Betelgeuse, curving slightly upwards, two hands spans worth of sky away.

There you will find a bright golden “star” near two bright, but slightly dimmer stars. That would be Saturn, the ringed beauty. The second largest planet in the solar system, it is easily spotted through amateur scopes and is a favorite at star parties.

Its main moon (one of over 30) is Titan, the rare satellite that can brag of its own thick atmosphere. Titan has been making a lot of news lately since we’ve managed to land a probe there, just weeks ago.

The spacecraft Cassini, which finally arrived in a comfortable orbit around Saturn last year after its launch back in 1997 - it takes a while to get certain places - dropped a probe named Huygens down onto chilly old Titan to see what makes it tick.

You can see all the great images from both Cassini and the Huygens probe of Saturn’s amazing rings, Titan’s spooky other-worldliness, and other bizarre creatures in Saturn’s zoo of satellites at the website for the mission: http://saturn.jpl.nasa.gov.

Hope our little tour of the southern skies was enlightening. Our next scheduled planetary package tour will be in spring starring the King of the Giants – Jupiter. We’re taking reservations now.]]>ritter777@gmail.comNone2005-03-13T11:18:12-08:00http://www.firstlightastro.com/skiesabove/files/0aca9c2424a76fb512823bc06365cf8a-125.php#unique-entry-id-125http://www.firstlightastro.com/skiesabove/files/0aca9c2424a76fb512823bc06365cf8a-125.php#unique-entry-id-125Quiz time!

But fear not! Before you begin suffering through those mind-altering flashbacks of pop quizzes you were forced to take in school, know this: This will not be graded, no letters will be sent home. You are only required to think, have fun, and simply classify the following statements as true or false.

1. The Sun burns stuff. It’s really nothing more than a big fat fire.

This is a common belief. And it makes common sense if you think about it. We see fires all over the place, from the fireplace to the forests. And we see the bright hot surface of the sun looking pretty similar. So the sun must be burning fuel just like these terrestrial conflagrations, correct?

Not really. The sun is hot because of a process called nuclear fusion. That’s when tiny atoms like hydrogen are smashed into other tiny atoms and fuse together to make bigger atoms like helium. When this happens some of the mass of the tiny critters is converted into enormous amounts of energy.

The “burning” the sun does down at its core is more like what goes on in a thermonuclear device, à la the fusion bomb. But instead of mere pounds of bomb material converted to energy, the sun converts over 4 million tons of matter into energy every second! And amazingly, even at this rate, the sun has enough fusion material left to “burn” for billions of years. Answer: False

2. Meteor showers rain down havoc on the earth! Everybody duck!

Meteor showers can be very dramatic fire-in-the-sky events but they are thoroughly harmless. They are just dusty debris from passed-by comets slamming into the atmosphere of the Earth. On average they are about the size of a grain of sand. But get them going at speeds of tens of miles per second and they can light up in a long fiery trail.

Most all the “shooting stars” we see are like this – whether part of a meteor shower or the strays we see occasionally flying solo through the night sky. They rarely make it to the ground, but their vaporized carcasses do give us tens of tons of extra new dust each day! Think of that next time you’re dusting behind the bookcase: you are probably wiping up some comet gut particles along with all the rest of the schmutz. Answer: False.

3. An asteroid or comet slamming into Earth will destroy the planet!!!

Imagine driving down the freeway at a good clip. Suddenly, without warning, a savage nectar-sucking butterfly flies right into the direction of your oncoming vehicle! Too late to react, the butterfly smashes into your front end splitting your car in two, both halves now careening off the road in different directions in a duel fireball of destruction.

This won’t happen, of course. The mass of the butterfly is way too small to cause any damage to your car other than an unsightly gooey mess. Asteroids and comets, even the bigger ones, are just miles, maybe a couple tens of miles across on average. When they hit Earth, which stretches thousands of miles through, other than leaving an unsightly crater they don’t do much damage to the planet at all. But they can really hurt the atmosphere.

Once they plough through Earth’s atmosphere and into its mantle they explode and hurl molten material literally all over the planet. This worldwide firefall ignites infernos everywhere, which pollutes the air on a global scale and shrouds us in darkness. Rainfall comes down as acid rain now, poisoning waters everywhere. Plant life suffers greatly. Being the bottom of the food chain, plants directly impact all the rest of life on earth. Lose those and mass starvation runs rampant.

Moreover, the sudden climate changes affect the complex, sensitive creatures the most, driving many to extinction. Earth is not a fun place to be for years. But the planet itself spins on, essentially unaffected. Answer: False.

Well, how did you do this time? Don’t worry if you got most wrong; these are all common misunderstandings. And, as my parents used to say, there’s more where that came from! In coming seasons we’ll try and debunk some more of these cosmic misconceptions.

Until next time, clear skies!]]>ritter777@gmail.comNone2005-03-28T11:12:50-08:00http://www.firstlightastro.com/skiesabove/files/427d1d8883f32a23d2809e766349d781-124.php#unique-entry-id-124http://www.firstlightastro.com/skiesabove/files/427d1d8883f32a23d2809e766349d781-124.php#unique-entry-id-124Water - it’s a blessing, it’s a curse. Well, for a self-centered astronomer it’s a curse anyway. Those darn clouds and that blasted rain and snow can ruin a night’s costly observing run at a premiere scope, indefinitely postponing important research.

And we amateur astronomers here in southern California have had to deal with plenty of the meddlesome wet stuff this year. Just a week ago our astronomy club had to cancel another star night for a local elementary school. A perfect cosmic setting - above all those clouds – passed over.

But how about for a moment we take off our astronomer’s cap, rimmed with a fringe of bad attitude, and just sit back and admire the tiny water molecule and see how utterly unique it is.

Composed of just one oxygen atom bonded to two hydrogens, water molecules are tiny to be sure. And molecules as small as water are almost always gases. Nitrogen, oxygen, and carbon dioxide - all bigger than water - are all gases in our atmosphere. There is no chance under present conditions that we will get an oxygen downpour or a nitrogen snow storm.

They don’t liquefy naturally on our planet because they just are not very “sticky” at all, and at these temperatures the little guys are moving just too fast to have any chance of holding on to each other. Then what gives smaller, faster water molecules the right to stick together so well that they not only form a liquid on our planet but a solid, as well?

It all has to do with the shape of those wee beasties. Because of the laws of physics, water is shaped like a little Mickey Mouse balloon. Imagine Mickey’s head as the oxygen atom and his two ears as the bonded hydrogens. So what? Well, this shape effectively gives water a slight charge.

The bonds that hold it all together are made of electrons and the oxygen has this greedy tendency to pull those bonding electrons more toward itself, away from hydrogen.

This means the oxygen has what’s called a “partial negative” charge on it. The hydrogens get stuck wearing a “partial positive” badge. So what we have here is a molecule with a negative side (Mickey’s head) and a positive side (his ears).

You can actually see this charge with a tiny experiment. Comb your hair to a fare-thee-well on a relatively dry day (remember those?). Bring the comb up to a thin, smooth stream of water from the faucet. The watery stream, attracted to the static-electrically charged comb, will bend towards it.

What’s this all got to do with the miracle of water? This charged character of water means that the little guys are attracted to each other – and rather strongly at that. This attraction allows them to stick to each other like socks to pants fresh out of a dryer.

This stickiness means they don’t mind congregating in the b-zillions to form tiny invisible droplets suspended in the air. If cool enough, these tiny droplets don’t mind at all clinging to each other, becoming big enough to be seen, as in fog or clouds. If conditions are right, these megadroplets don’t mind then gathering into conglomerates so big that they can fall as raindrops.

And the beauty of it all is that they aren’t too sticky. With a little energy thrown their way, the stickiness can be overcome and they are off by themselves again.

Just think of how important that is. Water molecules in oceans are sticking together. But at the surface where the water molecules are exposed to the pounding energy of the sun, they can leave en masse. They evaporate purely, leaving their salty ion friends behind.

Carried aloft they can travel literally thousands of miles. Cooling, they stick and fall as rain, injecting new life into an area, with the excess flowing back toward the ocean to start again.

Bottom line: That little molecule called water has been engineered so brilliantly – perfect size, shape, charge, etc. - that it can be transported deep into dry continents assuring life virtually everywhere on this great rock of ours.

Should I also get into the stunning ability of water to dissolve all kinds of stuff, allowing everything from erosion to the biochemistry in every cell of every living creature?

Should I elaborate on one unique property of water, unlike just about every other compound in existence, to actually become less dense when it is frozen, thus allowing ice to float rather than sink? Ice that sinks would turn our world into a giant iceball.

And on and on and on…

Yes, clouds and rain can wash out an otherwise perfect night of observation. But that little molecule, with its two H’s and single O, is a great work of art, worthy of observation in and of itself.]]>ritter777@gmail.comNone2009-09-07T10:32:57-07:00http://www.firstlightastro.com/skiesabove/files/b1ab962d4747801853c976691ca7a792-123.php#unique-entry-id-123http://www.firstlightastro.com/skiesabove/files/b1ab962d4747801853c976691ca7a792-123.php#unique-entry-id-123Seeing the stars at night, year after year, generation after generation, it seems that all is quiet up there. The stars appear fixed on that black canopy above. Nothing ever changes.

But stars are born, they live, they die. And it is because stars have a life cycle that we can make these bold statements: The skies we see tonight are our skies alone. Earlier in our history they were different. In the future there will be a whole new menage of constellations.

Explain!

Most of the stars we see in the sky have short lifetimes. Regular readers here will recall that most of the naked eye stars are intrinsically very bright, thus very energetic. This means they burn through their hydrogen fuel in short order, many in just tens of millions of years.

Now the Earth is over four-and-a-half billion years old. It follows then that most of our present-day stars have been up there only recently in our history.

Another factor in our changing sky is that stars are formed in nurseries. Here they interact gravitationally with each other. In doing so, some get tugged and flung out of the nursery, jettisoned into lonely space.

All this movement means that even if stars could live longer, they would not stay in the same place in the skies. They continue to move through it. Some are moving very fast, tens or hundreds of kilometers per second, others not so.

They don't appear to be moving because they are so very, very far away. But they do move. And this is another reason the skies are changing, however slowly.

Not only do stars appear in our skies over time, not only do they move through them, but they also vanish.

The biggest stars exit with the proverbial bang. They exhaust their nuclear fuel and collapse, then explode, into a supernova, vanishing from the sky altogether. Medium-sized stars fade away with a whimper, eventually shedding their outer layers and leaving nothing behind but a miniscule, hot corpse of a core.

On top of all this appearing and disappearing, in the future, because hydrogen gas in our universe is being depleted, the birthrate of stars will continue to decrease. There will be fewer stars to take the place of the dead and dying ones.

Stars are here for just one scene of one act of the Great Play, in really nothing more than a mere cameo appearance. So enjoy Orion and Sagittarius and the rest of the troupe while you can. In a couple millions of years from now, our heavens above will not be recognizable. ]]>ritter777@gmail.comNone2009-08-24T10:25:51-07:00http://www.firstlightastro.com/skiesabove/files/49a7399bc3485c2906117bbd3f4bbe95-122.php#unique-entry-id-122http://www.firstlightastro.com/skiesabove/files/49a7399bc3485c2906117bbd3f4bbe95-122.php#unique-entry-id-122Racial profiling has been a hot topic in our country for years now. Trying to figure out something about someone based on color is a matter for heated debate in the public forum. But in astronomy we judge based on color all the time. We have to. And here it’s pretty reliable.

There is no way to travel to a star and stick a thermometer in it to see how hot it is. We can’t land on these balls of gas and perform experiments. About the best we can do to find out how a star works is to try to replicate in our laboratories what we see out there, then infer things about that far distant star based on our findings. 

One of the characteristics of a star is its color. “Color?!” you may exclaim, “I thought all stars were just twinkling white things.” Not at all.

Stars come in all sorts of colors: red, orange, yellow, white, blue. But why? They are colored that way because of their temperatures. You have seen these colors here on Earth when different objects - often metals - glow when they are heated.

You may have seen an iron poker stuck into a fire. At first it gives off no visible light. But if one were to leave the poker in a hot fire for a longer time, you would notice it starts to glow red, then orange, then yellow. If you could heat up the metal in a very, very hot fire it would become “white hot.” Notice that these are all the same colors as stars. 

What you may not know is that if you could heat a substance up even hotter than that, it would begin to give off a bluish hue. 

Actually, these objects are giving off all the colors of the visible spectrum at once, it is just that they are giving off “mostly” red or orange or yellow, etc., so we see that predominant color as the overall “color” of that object.

Same with stars! The cooler stars are bleeding out mostly red, hotter stars mostly orange. The hottest, most dangerous stars pour out a lot of blue, hence their bluish hue. 

The colors of stars are giving us temperature clues, which in turn tell astronomers what is going on inside that hot gas ball trillions of miles away: how they burn, how fast they live, what they are made of. Stellar profiling based on color is an absolutely vital tool in the realm of astronomy.]]>ritter777@gmail.comNone2005-04-16T19:42:49-07:00http://www.firstlightastro.com/skiesabove/files/6cd82f5dd97d6947a68f28c9d9dfcf2d-121.php#unique-entry-id-121http://www.firstlightastro.com/skiesabove/files/6cd82f5dd97d6947a68f28c9d9dfcf2d-121.php#unique-entry-id-121There’s a great feeling that comes over us lovers of the brilliant night skies when we see the next generation get all lit up about it, too. We derive hope when a young person asks us questions about why Saturn has rings or what a star is made of or why the Moon makes those shapes. In there somewhere might be a future astronomer.

But what can also get us going is when we see the torch passed to the next generation of those who want to save our skies from an archnemesis many of us are unaware of – light pollution. Such a crusader is what I found recently in a young girl named Anzy McWha.

But what can also get us going is when we see the torch passed to the next generation of those who want to save our skies from an archnemesis many of us are unaware of – light pollution. Such a crusader is what I found recently in a young girl named Anzy McWha.

Anzy lives with her parents and little sister in Fallbrook, a city not known as a sprawling megametropolis. But even here the subtle saboteur of the skies can rear its ugly head.

Attempting to watch the Perseid meteor shower last year, nine-year-old Anzy found that it was considerably more difficult than she had anticipated.

Watching a meteor shower is pretty much like attending a play, it’s a no-effort event. You go out, let your eyes adjust, then look up and watch it happen. But Anzy and her mom found that it wasn’t so easy to do when a neighbor’s light lit up her backyard like the rising sun.

They had to hide in the shadow of their motorhome to attempt to see anything at all.

A couple months later her school, Sage Meadows Elementary in Fallbrook, went for a camping trip to the Mojave Desert. It was there that she discovered what experienced sky watchers know already.

“I was completely awed at how many stars I could see,” she says. It was there that this third-grader realized that we humans were ruining the skies with our artificial lighting.

What Anzy did next is what separates her from many of the rest of us. Instead of whining about it and then carrying on as if nothing happened, she decided to do something. She researched light pollution, did a project on it, and shared her findings with me a couple weeks ago at her home in Fallbrook. This is what I learned…

What it is...

There are several victims of light pollution. The first is obvious to science types and poets everywhere: It just plain wrecks the beauty of the night sky for all of us. And it does this in many deceptive ways.

One, called “light trespass,” occurs when light from one person’s property literally trespasses onto someone else’s. We’ve all encountered it; many of us are guilty of it. We all know of the neighbors or businesses nearby who feel it their civic duty to illuminate the known universe.

“Light glare” happens when lights get into your eyes rather than merely lighting the path in front of you. It’s not unlike being on stage where it is very difficult to see the audience because of the glare of the lights. But offstage, outside at night, it serves no purpose and can be dangerous.

“Light clutter” is just that - the parking lot or casino or auto mall that feels it vital for the good of society to completely overkill the lighting, using twenty lights when five will do.

“Urban light glow” is the one astronomers are most enraged by. The name says it all. It results in part from the previous three acting together. When light is unnecessarily aimed or reflected up into the sky, it casts an eerie sky glow wiping stars right off the horizon and eliminating all but the brightest stars above.

And all this costs the United States over a billion dollars (that’s “billion” with a “b”) in completely wasted light every year.

In a nighttime visit with Scott Kardel, the public relations director at Palomar Observatory, Anzy and her family and I got to see firsthand what The Glow is doing to research at one of the world’s premiere telescopes. Even with our not-too-sensitive human eyes, we could see what seemed like glowing ghostly domes over Temecula, Palm Springs, Oceanside, Escondido, and San Diego.

“People have either forgotten about what goes on up here or are under the false impression that we have special filters which make it all better, which we don’t!” reports Kardel.

“It not only ruins the images of long exposures of the sky, but important spectral work gets compromised, too,” he tells me. The spectra of objects in the sky – an array of all their visible wavelengths - reveal the compositions of stars and galaxies, essentially what the visible universe is made of. “The spectra of local artificial lights get mixed in with the spectra of what we are investigating, which makes it very difficult to decipher what’s going on up there.”

One astronomer recently told Kardel that he gets better results from smaller scopes in darker locations. Ouch.

The Other Victims

Those of us who are way too focused on the night sky forget that there is another population that is adversely affected by our unnatural desire to turn night into day. Anzy reminded me of these forgotten victims.

Animals of all kinds since time immemorial have used the skies to navigate, to migrate, to find mates, to time their breeding seasons. Our introduction of the nightly glow has not left them unaffected.

“Some insects, migrating toads, and salamanders are attracted to artificial light, and then aimlessly walk or fly around the light source. This makes it easier for predators to prey on them,” says Anzy.

There are hundreds of species of birds that migrate each year, many of which use the night sky to help them. Flying low, and confused by artificial lighting, many thousands die flying into buildings. Many more die from exhaustion from all the extra effort of misnavigating through a sea of man-made lighting.

Sea turtles when hatched use visual light cues to make their way to the ocean. But if there is careless human development going on near their birthplace, turtles can make their way towards those unnatural lights instead. On that path of death they are easy targets for predators - and automobiles.

The biological clocks of many animals in part rely on the day/night cycles and other natural lighting cues. When an area is flooded with artificial lights, the natural rhythms of the animals are offset and their sleep cycles and breeding rituals get confused. This results in them becoming easier targets for prey, or they might breed before the local food supply is ready for them.

Humans, too, have natural rhythms based on normal day and night cycles. We all know that a passive form of torture is to keep lights on during sleep time. But did you know that artificial lighting and its adverse affects on us have been linked to such diverse medical problems as myopia and breast cancer?

Common Sense Answers

So what can we do?

“Use common sense,” Anzy tells me matter-of-factly, but respectfully. Can’t argue with that. Not using a particular light? Turn it off. Too many lights? Remove some. Light pointing to the sky? There’s no reason for that; take it out.

But what about safety? Shouldn’t we light up an area to feel safe?

“But that doesn’t mean putting in the brightest light we can find, blinding everyone in the area, creating light trespass, and lighting up the night sky,” answers the young advocate.

There are all kinds of “good” lights we can get from the hardware store; lights that minimally affect nature, the sky, and our neighbors – and keep us safe. These sky-friendly lights will soon be marked “IDA-approved.”

The IDA is the International Dark-Sky Association, an organization founded to reclaim the skies. They have an entire list of good lights, all of which essentially aim the light downwards, away from the sky and neighbors and eyes. (Find out more about them and all kinds of light pollution info at darksky.org.)

But their approved lights cost a little more than regular lighting. To no one’s surprise, young Anzy has a responsible answer for that, as well.

Not only do these good lights greatly reduce light pollution – a good reason for getting them in and of itself - but the lower wattage of the IDA lights means using less electricity. “They pay for themselves in two years!” says Anzy.

Her mom, Jane, adds to that. “We can’t go anywhere now without Anzy giving a running commentary on the lights we pass by…”
“Yeah, we say ‘bad light, good light, bad light, bad light, bad light, good light,’” Anzy says, finishing her mom’s sentence.

The Flick of a Switch

Anzy’s advice for dealing with a neighbor with a lighting problem? “Be really nice, tell them about the problems of bad lighting, and help them to find remedies for their situation.” That’s being a good neighbor.

Back at Palomar Kardel, involved in the local politics of lighting, goes further. He says that Riverside and San Diego Counties have laws that govern what type of lights may be used and when they can be lit. He says that if there is an issue with someone’s light, if they don’t listen to your friendly advice, to call the City or County Planning office and report it.

Being responsible for light pollution helps the environment, saves money, keeps us healthier, and brings back the night skies for us and future generations.

“Landfill problems and water pollution will take some time,” concludes Anzy McWha, wise beyond her years, “but light pollution can be solved by the flick of a switch.”
]]>ritter777@gmail.comNone2005-04-23T19:39:32-07:00http://www.firstlightastro.com/skiesabove/files/480edcfdaf2739538bb75a1d9f637ef4-120.php#unique-entry-id-120http://www.firstlightastro.com/skiesabove/files/480edcfdaf2739538bb75a1d9f637ef4-120.php#unique-entry-id-120

Statement 1: There are places on Mercury that actually see double sunsets.

Mercury, the first planet from the sun is very close to our star, and as a result has felt a stronger gravitational pull than the rest of us. This greater pull actually brakes the planet into a slower spin time, a slower “rotation.”

Consequently one Mercurian “day,” one complete planetary pirouette, is nearly 59 earth days in length. And you thought your days were long.

Its year, how long it takes to go around the sun once, is only 88 earth days. This and the fact that its orbit isn’t a nice perfect circle make for some crazy phenomena.

The sun is actually in Mercury’s sky for 2-4 months at a time. You can imagine that a very close sun beating down for months nonstop can make for some pretty oppressively hot temperatures. Try 800 ˚F worth of hot.

Conversely, the long months of no sun at all result in temperatures that plunge to about -280 ˚C. Over one thousand degrees difference between nighttime and daytime probably disqualifies Mercury as a popular tourist spot.

Moreover, Mercury’s orbital geometry makes for a particularly strange occurrence. Because of the combination of slow rotation, quick revolution, and oblong orbit, there are places on Mercury where the sun will slowly sink below horizon, then surprisingly rise again, only to sink below a second time. Granted this takes several weeks to accomplish, but you can imagine this is one singular event in this solar system of ours. (Answer: True)

Statement 2: A day on Venus is longer than its year.

Venus, closer to the sun than we are, takes a shorter time to buzz around it; two hundred twenty-five days compared to our 365. But it takes even longer to spin around even once on its axis. A single “day” on Venus, one complete spin, lasts 243 Earth days! Combined with its revolution, the sun is “up” in that sky for about 2 months.

And of course it is “down” – below horizon - for another couple months, as well. But does that mean it is really hot during the venusian daytime and really cold during night? Not by any stretch of the imagination.

First, no one ever sees the sun in the sky on Venus, it is so unbelievably cloudy there. But that same cloud cover acts like a monster blanket, keeping it scorching hot all the time, day and night. The average temperature is nearly 900 degrees Fahrenheit, hundreds of degrees hotter than your stove at full blast. (Answer: True)

Statement 3: Mars has two moons, but soon it will have only one!

There are two tiny little satellites orbiting our outer neighbor Mars. Tiny is perhaps too weak a word. They are but miles across. Phobos is just 17 miles through. Deimos, farther out than Phobos, is only a 9-mile chunk of rock, the size of a decent sized city.

The small mass of these two means their gravity is near zero. A high jumper who can clear 6 feet on earth could set the bar to over a mile and a half on Phobos - and clear it easily.

An observer on Mars looking for his moons can see just a bright speck as Deimos passes over. But as Deimos passes over one way, Phobos races by overhead in the opposite direction, twice a day.

Poor Phobos, like the name implies, has reason to fear. It passes over twice a day because it orbits so dangerously close to Mars. In fact, it is on a collision course with its parent.

So close means Mars, via the laws of gravitational physics, will eventually pull Phobos into itself. In the next 50 million years or so, Phobos is doomed to crash into the planet or break up into bits giving Mars a tiny, temporary ring system. This will leave Deimos as the lone Martian satellite. (Answer: True)

Hope you did well. Until next time, clear skies!]]>ritter777@gmail.comNone2005-05-07T19:21:52-07:00http://www.firstlightastro.com/skiesabove/files/6d994476488a8b5cda9319355fa9b68d-119.php#unique-entry-id-119http://www.firstlightastro.com/skiesabove/files/6d994476488a8b5cda9319355fa9b68d-119.php#unique-entry-id-119For someone trained in the sciences there is always the problem of turning a perfectly beautiful experience into a mere compilation of data. Studying nature too deeply for some puts calluses on their senses of beauty and design. They suffer from the proverbial missing-the-forest-for-the-trees syndrome.

Maybe the best way to observe an object in nature lies somewhere between the arts and the sciences. Let me give you an astronomical example of what I mean.

There is an amazingly beautiful picture of our home planet at a NASA website called Blue Marble (http://earthobservatory.nasa.gov/Newsroom/BlueMarble/). It is a stunning composite made of countless images of our planet, all sewn together into one marvelously detailed blue, green, brown, and white image.

Many see this and are simply awed by the grandeur of it. I have to be told to close my mouth and quit staring.

But allow me to try and enhance this magnificent image at the risk of seeming like a cold, clinical scientist.

Looking at this planet I can, with my mind’s eye, see down through the surface, deep into the center, where lies the inner core, an intensely hot and glowing ball of solid iron and nickel.

Thanks to a miraculous collision by a Mars-sized planet over 4 billion years ago, a collision that spilled the guts of the impactor into a newborn Earth, we inherited a larger, hotter core than we had when Earth was conceived. The radioactive heat from that terrible transfusion keeps our planet in a somewhat molten state, critical for life.

Enveloping the inner core is a thick outer core of hot liquid metal that swirls around in gigantic eddies. The churning creates a protective magnetic field encompassing the earth, saving us from dangerous, electrically charged particles spewed from the sun and providing us with the beautiful aurorae at the poles.

Surrounding both these cores you can imagine a thicker, cooler, hardened layer reaching nearly to the outer surface of the globe. On this “mantle” is painted a thin layer of crust, the layer we call home. This paper-thin coating is just thick enough to allow some pretty amazing phenomena.

As hot material rises from the lower layers it forces our crust to move about on colossal slabs called tectonic plates. This movement is important because it provides us with volcanoes and mountains, hills and valleys, coasts and islands.

Where plates collide we have island chains and gigantic mountain ranges, like the Aleutians, the Andes, Japan, and the Philippines. Where they split apart we have oceans and immense rift valleys, like the entire Atlantic Ocean and the Horn of Africa. Where the huge landforms scrape by each other, they crushingly reshape the land as they have in California.

If that visible, colorful crust were thicker, there’d be no movement. If it were thinner, we’d have considerably more deadly tectonic activity. The thickness of the crust at this moment in our history scores a perfect 10. It couldn’t be better.

The image of our planet shows us the fragile, thin atmosphere we have been given. It is composed of about 80% nitrogen and 20% oxygen - perfect for complex life like us. Not much more than a trace of carbon dioxide remains from the early days of infant Earth. But there’s just enough to warm us and keep those plants alive.

Also invisible in our thin cloak of atmosphere is a layer of ozone, protecting life below from deadly ultraviolet rays.

The clouds are more obvious, sweeping magnificently across the globe. Those are wisps of life there. They are water carriers delivering their precious cargo to all parts of the planet. A planetary scientist sees this as perfection. There is not too much cloud cover, not too little – it’s just right.

And the elegant, sweeping shapes of the clouds remind us that the planet is spinning at just the right speed; not too fast, not too slowly.

Seeing a picture like this strikes in us a profound sense of beauty, like staring at Michelangelo’s David or Raphael’s Sistine Madonna. There is just something inherently exquisite and aesthetic here. It is a beautiful ball in the heavens, probably the only one of its kind, and a work of cosmic art.

And the more we find out about her - the more we know of her inner design, her deliberate activity on the surface, the sensitive, frail atmosphere covering her - the more lovely she appears.

Maybe the best way to look at this Blue Marble, our great gift of a home, is with the heart of an artist and the mind of a scientist.
]]>ritter777@gmail.comNone2005-05-28T19:17:01-07:00http://www.firstlightastro.com/skiesabove/files/d67493e016819d1702963ec508f51a0c-118.php#unique-entry-id-118http://www.firstlightastro.com/skiesabove/files/d67493e016819d1702963ec508f51a0c-118.php#unique-entry-id-118What bright object in the night sky this evening has highlands and seas? If you guessed the Moon, you are on the money - sorta.

Tonight the Full Moon shines bright as it rises in the southeastern skies. Its incredible glare lights up the sky so much that it’s hardly worth mentioning other objects up there, seeing as they can’t be seen.

But a look at the Full Moon will reveal some interesting characteristics about our nearest planet-like neighbor.

See there the vast dark areas surrounded by bright whiteness. Some see in the overall view the traditional “man on the moon.” I see a dark rabbit as if it’s being lifted up - head and ears to the “left,” body arching over to the long back legs on the Moon’s “right” side. Don’t see it? It’s OK.

Neither do most of the students in my class. Alas!

We might agree, though, that the full Moon is pretty bright. But surprisingly it’s only as bright as the asphalt on your street. It’s albedo, a fancy word that tells us how much light is reflected off of something, is only 0.06. Translation: it reflects only 6% of the light it receives. Earth, that bright beauty with all its reflective cloud cover and polar caps has an albedo of 0.39, more than 6 times that of the Moon.

But why are there the dark parts of the Moon (the bunny) and the light parts? It was a mystery for a long, long time.

Galileo was first to see the detail on the Moon with his fancy new telescope. He could see that the bright areas were covered in crater-shaped “mountain” ranges. The dark parts, which he called seas, or “maria,” were to him craterless.

It wasn’t until this last century that we finally figured out what it all was.

The light parts, heavily pockmarked with craters, were not the result of volcanic activity or mountain-building processes as was widely held. Those were impact craters and their debris, from lots and lots of giant impacts.

This idea didn’t fly well at first since huge impact craters smacked of catastrophe, something that didn’t happen according to the prevailing philosophy of the day, a worldview that said that things happened slowly over long periods of time.

Then what on earth were the Moon’s dark areas made of? Why didn’t the impactors impact all over? They did, in fact. But these dark spots turned out to be lowlands, which filled in with moon lava and covered old craters billions of years ago when the Moon was still geologically active.

These smooth and relatively safe areas, the “seas,” were where the first Apollo missions landed. Hence the famous “Sea of Tranquility,” the landing site for Apollo 11.

It wasn’t until we sent spacecraft to the Moon that we could see the far side of our satellite. Here we discovered just about nothing but crater-filled highlands. The maria turn out to be pretty much a show exclusively for Earthlings.

And all these moon craters, great and small, got scientists to ask the obvious questions. If the Moon, smaller and with less gravity got hit that often, what happened to us? Why aren’t we chock full o’ craters?

It turns out we’ve been hit a lot more than the Moon. But we have this excellent recycling program set up on our planet that resurfaces many of the impacts and buries others with plate tectonics. Our atmosphere also helps to break up many before they hit us, and our vast oceans hide many scars.

But there are still dozens and dozens of impacts above ground like Barringer Crater in Arizona - reminders that overall we’ve got it pretty good here on this beautiful planet of ours.

Go out tonight after sunset and see again, but with new eyes, our amazing satellite.]]>ritter777@gmail.comNone2005-06-05T19:11:49-07:00http://www.firstlightastro.com/skiesabove/files/6f33c089bf7e69cae3d81edeb363f810-117.php#unique-entry-id-117http://www.firstlightastro.com/skiesabove/files/6f33c089bf7e69cae3d81edeb363f810-117.php#unique-entry-id-117We’ve recently passed two of the great gas giants, Jupiter and Saturn, in our orbit around the sun. Both of these planets are still up in the early evening skies, Jupiter overhead, Saturn more to the west.

Maybe now would be a fitting time to take a quick little quiz about the outer planets - Jupiter, Saturn, Uranus, and Neptune. The statements below are all true or false, but remember, as usual, you will not be graded - but you must have fun!

Statement 1: The gas giants are made of gas.

Asking people what the four gas giants are made of is like asking who’s buried in Grant’s Tomb. “Gas giants” pretty much spells it out – they are giant planets made of gas, of course.

Kinda, sorta… not.

If by gas one means hydrogen and helium and methane then yes, the four jovians, as they are often called, are all pretty gassy. But (cue dramatic music) those elements and compounds aren’t always gasses!

The outer layers of the planets are gassy, to be sure, with their cloud patterns and storms like that Great Red Spot on Jupiter. But when you sink below the cloudy upper deck and in through an outer layer of gaseous hydrogen, the atmospheric pressure starts to kick in pretty heavily, and things change dramatically.

Going further down, the pressure becomes so great that the hydrogen gradually becomes a liquid. Go further down into Jupiter and Saturn where the pressure reaches about 2 million times what it is here in our atmosphere and the liquid hydrogen becomes the rare metallic hydrogen.

And way, way, way down deep is a rocky core, probably as big as Earth, experiencing pressures greater than 50 million times our own atmospheric pressure.

Uranus and Neptune aren’t big enough to have the liquid hydrogen but neither are they completely gassy.

Below their upper cloud decks is a thick layer of gaseous hydrogen. But down below that is an entire sphere of icy water and ammonia and methane. And way down deep they, too have a rocky core.

So, yes the “gas giants” have lots of gas, but they are no means the great gas bags in space many people see them as.

Answer: false

Statement 2: The fact that they are all gigantic and have lots of gas gives us hints into how they were created.

When one sees four inner planets, grouped together and all earthlike, surrounded by distant gigantic planets all bathed in hydrogen and other gases, us nerdy science types get all excited. There’s a pattern here and the planets are trying to tell us something.

What we believe these giant outer four are telling us is that they were formed about the same time, far away from a burning sun.

Far away means cooler, and cooler means different materials can be used as building blocks for planets; like gases and water ice, for example. Try building a planet of gas near a star and it won’t work. The gases get blown away by the star. That’s why the inner planets are all rocky bodies.

But the Gas Giants are telling us that out there hydrogen and helium and methane and even frozen water can be used to build planets. And the huge masses of Jupiter and Saturn indicate that there was a lot of “stuff” to vacuum up out there in the early days of our solar system, but not so much way out where Uranus and Neptune were created.

Answer: true

Statement 3: Of the gas giants, only Saturn has rings.

Saturn’s rings were the first to be seen when Galileo spotted them nearly 400 years ago. But it wasn’t until the last decades of the 20th century that the other jovian planets revealed their own little secrets.

It turns out that all four have ring systems. Of course Saturn’s is most famous and arguably the most beautiful. But Jupiter has a faint ring system of its own, made of dust so small that it can’t reflect light back towards us. That’s why we can’t see it from here. But spacecraft flying behind it have seen its dispersed light and imaged it.

Uranus has its own unique and beautiful ring system that now, with powerful telescopes, can be seen from here.

And distant Neptune has a bizarre ring system, barely there, and made of barely visible carbon compounds making it very difficult to see even by the Voyager spacecraft that have flew by years ago.

Answer: false]]>ritter777@gmail.comNone2005-06-19T18:34:01-07:00http://www.firstlightastro.com/skiesabove/files/ba522401c08372a3a4cf6d440ab87e8d-116.php#unique-entry-id-116http://www.firstlightastro.com/skiesabove/files/ba522401c08372a3a4cf6d440ab87e8d-116.php#unique-entry-id-116Some of the planets are currently playing a trick on us. This prestidigitation involves neither smoke nor mirrors, but like any good trick it does take advantage of illusion.

In the western skies this week, just after sunset, there will be three planets appearing to group together for a family portrait. It will end up being a tight shot, to be sure. Then after the weekend they will seem to go their separate ways. But are they really that close, nearly bumping?

It is this wandering characteristic that got the planets their name in the first place. Thousands of years ago the ancients noticed that the stars in the heavens were fixed, they didn’t move about. They predictably showed up in the same heavenly real estate year after reliable year.

But there were some stars that seemed to “travel.” Throughout the year anyone who kept an eye on them saw that they sort of… well, really wandered through the sky. So they were given the name “planets” from the greek work “planetes,” which means, to no one’s surprise, wanderer.

Of course we now know that the planets are not stars, but small rocky and gassy bodies orbiting the sun. They are not the incredibly distant actual stars that are so far away that most don’t appear to move at all in a person’s entire lifetime.
And since all the planets move on essentially the same plane, there are going to be times when they appear to get real close to each other.

Such is what is happening this week as Venus, Mercury, and Saturn group together for a nice portrait after sunset. But the grouping is just an illusion; they will be nowhere near each other. Let me tell you how they pull it off.

We are in the part of our orbit where we have passed distant Saturn months ago in our run around the sun, but are now being chased by Mercury and Venus on their inside tracks.

Imagine racing around a track with all runners in staying in their own lanes. Imagine looking back as you run around the turn, seeing a distant runner that you have already passed but, at the same time, spotting two runners who are fast catching up with you on the inside lanes.

Imagine looking over your shoulder at the precise moment when it appears that they – the runner you have passed and the two catching up – are coincidentally in the same line of sight. They appear to be grouped, but are actually nowhere near each other.

That’s what we’ll be seeing all this week about 45 minutes after sunset. We are actually looking back and seeing Mercury and Venus rounding the sun and ready to move by us, as poor distant Saturn lags way, way behind.

But it appears they are all gathering in one spot in the sky.

You can start watching this evening. Venus will be the brightest dot in the twilight skies. A good eye will pick out dim Mercury to its lower right at less than three degrees away. Saturn is a brighter dot on the opposite side of Venus and slightly farther.

Go outside about the same time in the next few days and see for yourself how it appears that Mercury is approaching Venus from below, Saturn from above. They are all “wandering” as they did for the ancients for thousands and thousands of years.

It all comes to a climax over this coming weekend when, over successive nights, the three - now so close they are called a “trio” in astronomy parlance - get together in the closest trio since the last century. The only thing missing from this sky scene is a beautiful crescent Moon as a backdrop.

Mind you, Saturn is actually 800 million miles farther away than our two inner neighbors, who themselves are more than 40 million miles apart. Remember their “grouping” is just part of the illusion.

After the weekend they will begin to part ways again. These get-togethers never last.
If you get a chance to see it, do. There will be another trio next year, but its proximity to the sun will make it very difficult to appreciate. After that you’ll be waiting decades for another great grouping of these wandering magicians.]]>ritter777@gmail.comNone2005-07-03T18:27:41-07:00http://www.firstlightastro.com/skiesabove/files/7f20063e6c7b148a5ef9ad8386776516-115.php#unique-entry-id-115http://www.firstlightastro.com/skiesabove/files/7f20063e6c7b148a5ef9ad8386776516-115.php#unique-entry-id-115If all goes according to some very intricate planning, the first fireworks celebrating Independence Day will actually happen late night on Sunday the 3rd, at about 11 PM our time. It will happen about 83 million miles away, and you won’t be able to see it unless you have access to a telescope. But it will be big!

Here’s what’s up.

We all know that there are objects in the solar system besides our familiar sun and planets. For example, we have the asteroids, b-zillions of them littering the place. Most are between Mars and Jupiter, but some pass nearby and pose real threats to us.

But we also have our comet visitors, those long hairs from outer space. Far from being the portents of doom that they were to many of our ancestors we now know some things about them – but not everything, by far.

We know from where they probably come, we know how the tails form, we know basically what they are made of – well… kinda sorta. Their full chemistry and how they hold together remain mysteries. And knowing these objects well, these fossil remnants of the creation of the solar system, can help us understand how the whole place was put together more than 4.6 billion years ago.

But to know more about comet innards we have to throw something at it and break it. It’s a common thing in science, this sort of invasive surgery. Physicists throw subatomic particles at each other to see what they are made of; geologists crack open geodes to reveal the beauty within. Now astronomers will throw one fast moving projectile at a comet, Comet 9P/Tempel 1, to reveal the secrets within.

Twenty-four hours before the fireworks begin, NASA’s Deep Impact spacecraft, launched last January and headed for Temple 1 at a breakneck speed, will toss off a washer/dryer-sized projectile towards the 8-mile-across comet. This tiny projectile, weighing in at 820 pounds, will be traveling so fast, 23,000 miles an hour, about 6 miles per second, that when it hits it will be like lighting up 5 tons of TNT. No small explosion that.

The engineers working on it estimate that this tiny projectile will punch a crater into the comet bigger than a football field and about 50 meters deep.

Meanwhile, the main spacecraft will zip by the comet as it happens, recording the whole event from a safe distance.

So what? How can slamming something into a comet tell us its composition?

By studying the impact, scientists can estimate how hard the surface is. Is the comet layered through like earth, with a crust and core? Or is it a thrown together mess? Seeing the size of the impact and the depth of the crater will help these investigators figure that one out.

How far the blast debris (the “ejecta”) gets thrown depends on the gravity of the comet. So observing where the ejecta settle can help estimate density and possibly what stuff is deep down inside.

Analyzing the spectra of the light reflected by all the fireworks will help astronomers figure out what compounds make up the surface of old Temple 1.

And of course the images, close-up and finely detailed, will help determine perhaps how she’s put together at the surface.

But understand that no comets will be harmed in this experiment. One engineer compares the collision to a gnat striking the windshield of a Boeing 747. Only one fatality there.

We on the West Coast might – key word: might – be able to see it when it happens. It’s always a tough call predicting what might happen – there are so many variables – but some scientists predict that the impact might be bright enough to be seen with a backyard telescope. That’s worth breaking out the scope for backyard astronomers like myself.

If interested in the details of when, where, and how, see http://deepimpact.jpl.nasa.gov.
]]>ritter777@gmail.comNone2009-08-10T21:12:00-07:00http://www.firstlightastro.com/skiesabove/files/5ba93c220796a95c1272b25373a65de7-114.php#unique-entry-id-114http://www.firstlightastro.com/skiesabove/files/5ba93c220796a95c1272b25373a65de7-114.php#unique-entry-id-114Going on a vacation to see some of the beauties of nature often involves a lot of work. One must plan, make reservations, pack, get time off, fly or drive to "enjoy" that trip to Yosemite or Yellowstone or the Grand Canyon. Of course it is worth it - they are all terrestrial works of art - but there are some natural wonders which we can enjoy from our own backyard.

Of course I am talking about the sky; but more specifically here, a meteor shower. And - surprise! - we have one in the next days.

The annual Perseid meteor shower is scheduled for its appearance though the middle of this week, more precisely the nights of the 11th and 12th, and the 12th and 13th.

Recall that a meteor shower happens when Earth barrels through a comet's debris train. A what?

Comets, made of ice and organics and dirt, circuit through our solar system often. Some are in hugely elliptical orbits which take decades, sometimes centuries to complete. A few comets have orbits which intersect our own. It is tragic if Earth and comet happen to meet at that intersection at the same time, but we almost never do.

The comet does give off a lot of its dust and ice and other debris as it goes around, especially when it is close to the sun. It is that thrown-off stuff that we are pretty much guaranteed to hit as we cross orbits.

And as we do run into the debris train, those dusty remnants smash into our atmosphere at breakneck speeds, vaporizing the little guys in streaks of light which we call meteors.

We cross the thickest part of the debris train of a comet called 109P/Swift-Tuttle at about midday on the 12th. Bad news: We miss the peak for nighttime viewing. Good news: We can see the shoulders of that peak either the night before or that night.

Sadly, the waning, but still bright, third quarter moon will be up brightening the sky after midnight, just when it is best to see the shower. But that's OK. The Perseids are reliably big and bright and beautiful.

When you go out to watch them, your best bet is from just before midnight to dawn (when we are headed into the stream). You merely need a place to lie down and look up. If it is a warm evening don't forget the bug spray. Mosquitoes see you as a healthy meal lying there all unprotected. Trust me on that one.

Enjoy with your friends or family this inexpensive summer vacation to a natural wonder. ]]>ritter777@gmail.comNone2009-07-27T15:52:15-07:00http://www.firstlightastro.com/skiesabove/files/9f810890493f0373f7e5e726dfa0e439-113.php#unique-entry-id-113http://www.firstlightastro.com/skiesabove/files/9f810890493f0373f7e5e726dfa0e439-113.php#unique-entry-id-113These last weeks we have celebrated the truly historic events in the history of mankind of not only getting to another heavenly body, specifically the Moon, but actually landing and walking on it. Those of us who were alive then will never forget it. What a blessing it was to be one of the privileged few to observe a genuine milestone in the history of humankind, at the same time believing that our venture into space had finally gone beyond science fiction and was now a reality.

Suddenly the realistic setting (if not premise) of 2001: A Space Odyssey, which came out the same year, didn't seem so far-fetched. Real space stations, real settlements on the Moon, real manned space travel to different planets within our generation was conceivable; it could happen!

But it has not. And in the grand tradition of science, allow me to make a prediction based on the facts: Sadly, it probably won't.

The last 40 years have been a reality check, to be sure. In this last generation we have discovered some things about ourselves and the universe which, I believe, have put a big fat roadblock in the way of our quest "to boldly go where no man has gone before."

One reality check is that elaborate space projects are stifled by politics and time and money and legalities. Just look at the sisyphean International Space Station. That one spacecraft is still being built at immense expense despite over a decade of international teamwork.

And consider our interest in it all. We are a fickle species to be sure. Our interests wax and wane in very short time spans. For example: Many people know the men who went up on Apollo 11. But this week marks the anniversary of the landing of Apollo 15. Name one of the astronauts, or where they landed, or what they accomplished, even the year they went up. After Apollo 11, interest in the Moon crashed. No public interest means little - if any - government support. Lose that and your project is doomed.

Another problem: Today we know a lot more about our solar system than we did back then, and our neighborhood, it seems, is a disk of death. Mercury, Venus, the "gas giants," their moons - most all are off limits for us. They are lethal. But what about Mars?

Space travel to even that closest, "friendliest" planet is a logistics nightmare. Cramming a handful of people into a small capsule for nearly a year just to get there poses profound physiological and psychological problems. Imagine attempting to get beyond our solar system!

The list goes on. Understand that I don't like this. I dreamed of going to the Moon when I was a kid; I still do. I enjoy the interplanetary travel in movies like Star Wars and its genre (providing there's a good plot!). But when we come down to it, it is still science fiction.

To be sure we are meant to move, explore, venture laterally across the surface of our privileged home. But I have a bad feeling that going up, up and away ain't happening.

Still, it would be cool.]]>ritter777@gmail.comNone2009-07-13T21:33:38-07:00http://www.firstlightastro.com/skiesabove/files/ec2fe9d959e236ec16e27f4a981e76f3-112.php#unique-entry-id-112http://www.firstlightastro.com/skiesabove/files/ec2fe9d959e236ec16e27f4a981e76f3-112.php#unique-entry-id-112This week let’s have ourselves a little awards ceremony. We’ll call them The Solies, awards to planets in our solar system which are at the top of a particular category. Ready? 

In a shocking upset, the Solie for Hottest Planet goes not to Mercury, but to its fellow planet farther out, Venus! One would think Mercury to be the clear winner here, being so close to the sun as it is. But Venus has an extra characteristic that little Mercury does not possess. It has an atmosphere - a thick, nasty, carbon dioxide-filled one which can hold onto heat extremely efficiently. Its average temperature at the surface is a warm 900 degrees Fahrenheit. 

As a consolation prize we’ll give Mercury the Solie for Greatest Day/Night Temperature Difference. Mercury has one heckuva long day. One sunrise to the next lasts about 180 of our days! During its “daytime,” its temp sores to 800 degrees Fahrenheit, but when that same surface turns away from the sun and has months to cool down, it does so with a vengeance, cooling to 280 degrees below zero. Overall difference: over 1000 degrees. Congratulations, Mercury!

The Solie for Most Massive Planet goes to... Jupiter! Now this probably comes as no surprise to you; most people would predict Jupiter the winner here. But what you may not know is that Jupiter is made of more mass - more “stuff” - than all the other planets combined! It is a genuine heavyweight. But wait! Isn’t it only just slightly bigger than Saturn? How can it be so much more massive?

Recall that more mass means more gravity. And recall also that gasses can compress. Jupiter has a lot more mass than Saturn and all the rest combined, but its outer gaseous layers are compressed under that greater gravity. That’s one reason why adding more stuff to Jupiter doesn’t allow it to grow appreciably. 

The Solie for Least Dense Planet goes to... Saturn! But how, if it is so huge! Remember that how dense something is isn’t the same as how big something is. How dense an object is tells us how much stuff is crammed into a certain volume. So something can be huge, like Saturn, but not be made of a whole lot of stuff. So it isn’t too dense. 

In fact, Saturn’s average density is less than that of water, but don’t try floating it in a great ocean to see if it will float. It might stay afloat in your imagination, but in real life, too many physical factors prevent this grade school analogy to work.

Our final Solie was a unanimous choice. This planet is not biggest, smallest, closest, farthest, hottest, coldest, or densest - none of those. But one could write books about the myriad subtle characteristics that make this planet the clear winner for being the one most consistently and artistically designed for life. Our Lifetime Achievement Solie goes to our own home: Earth. 

Congratulations, Earth. May all your inhabitants learn to appreciate just how beautiful you are.]]>ritter777@gmail.comNone2009-06-29T21:31:44-07:00http://www.firstlightastro.com/skiesabove/files/fd6e68cbe2cf4f6cd9239c2890e1d1dc-111.php#unique-entry-id-111http://www.firstlightastro.com/skiesabove/files/fd6e68cbe2cf4f6cd9239c2890e1d1dc-111.php#unique-entry-id-111The sky is vast. I mean vast. But one would think that with all the telescopes we have now probing through the heavens every night that almost nothing would escape our notice. Right? Wrong.

The scopes that we have now are powerful, to be sure, but are completely focused on just infinitesimal specks of sky. Even if hundreds of scopes are up at any given moment, most heavenly events go completely unnoticed.

That is why one of the latest technical innovations just hitting the airwaves holds such great promise. And it is happening on our very own Palomar Mountain in a project called the Palomar Transient Factory (PTF) survey.

We all know of The Telescope on Palomar, the 200-inch Hale inside that monstrous white dome. But there are other scopes there, as well, contributing nightly to the advancement of astronomy.

One is the Samuel Oschin 48-inch Telescope located in a dome just a stone's throw away from the Big One.

What is special about this scope is that it has an amazingly wide field of view, covering an area of sky greater than 15 Full Moons; no speck of sky here. And it has a huge digital camera attached, 100 megapixels strong to be exact. So what? So this:

In days of old, astronomers would spend literally hours trying to expose just one tiny fleck of sky onto a photographic plate. Now, the camera mounted on the Samuel Oschin scope with that super-sized, superfast camera can take over 100 gigabytes worth of images a night. That's enough info to fill an average computer hard drive. But that's not all!

In days of old - well, even now - astronomers then have to pour over those images and look for stuff that's new or different. That consumes a lot of time.

The PTF survey is set up so that it can take all those images and send them wirelessly to computers which then sift through the images automatically to search for new objects.

If the computers find something out of the ordinary, they can alert observatories throughout the world, giving them a "heads up" that maybe something worth looking at is in a particular part of the sky. The PTF survey is putting a million eyes on the sky at once.

What can it detect for us? All kinds of supernovae, cataclysmic variable stars, possible planets around other stars, near-Earth asteroids, oh my! And it finds them fast.

"Today I found five new supernovae before breakfast," says Caltech's Robert Quimby, a postdoctoral scholar and leader of the PTF software team. "In the previous survey I worked on, I found 30 in two years."

Modern technology combined with a workhorse telescope are adding to our rapidly growing knowledge of our beautiful universe. Go team!]]>ritter777@gmail.comNone2009-06-15T09:19:59-07:00http://www.firstlightastro.com/skiesabove/files/34ebe3898c2210d886af217351de2200-110.php#unique-entry-id-110http://www.firstlightastro.com/skiesabove/files/34ebe3898c2210d886af217351de2200-110.php#unique-entry-id-110In the next days we mark an anniversary of a discovery made in 1978 that wasn't exactly an earthshaker, but is an interesting look into astronomy, nonetheless.

You may recall that Pluto was discovered in 1930 by a young astronomer Clyde Tombaugh. He noticed that in several images of a particular part of the sky taken some time apart that the stars were stationary as expected, but that there was a small dim dot moving slowly through them. Long story short: It was Pluto.

Those were more simple times, when a new spherical body in space found in an orbit all by itself would just naturally be christened a new planet, no questions asked. And it was a time when a body revolving around a planet would just naturally be called its moon.

Well, in 1978, on 22 June to be exact, astronomer James Christy noticed that the best images we could get of Pluto back then periodically showed a slight bulge. It turns out that that bulge was not the result of crummy photography, but was really a small spherical body circling Pluto. Christy had discovered a wee moon around tiny Pluto!

Legend has it that he named the new moon Charon, after his wife Charlene, whom people called "Char" for short. This kind of went against the tradition of naming heavenly bodies after Greek or Roman mythological beings. But lucky him, Charon was also the name for the mythical boatman on the river Styx, the one who ferried souls off to Hades. So Charon stuck.

There they were, Pluto and Charon, planet and moon, living happily together. Until recently that is.

You may recall that Pluto has had some problems lately among astronomers. It was demoted from planet to... well, all kinds of things: dwarf planet, transneptunian object, Kuiper Belt Object.

If Pluto is a dwarf planet then it might follow that Charon is just a moon of a dwarf planet. But - surprise! - it is more complicated than that.

Pluto and Charon are both pretty similar in size, so much so that Charon doesn't really go around Pluto like the Moon around us - a little guy circling about a barely moving big guy. Pluto and Charon's mutual center of gravity is somewhere between the two in space. They are more like two people holding hands and spinning around and around some common center between them, rather than like a stationary person swinging a ball around on a string.

This is disturbing enough for some astronomers that Charon and Pluto are being looked at as a possible dwarf planet duo.

What is Charon's status at the moment? It is still a moon by most accounts, at least until the International Astronomical Union officially defines what a large moon of a dwarf planet is. Sheesh!

O, for the simpler days when there were but mere "planets" and "moons"!]]>ritter777@gmail.comNone2005-07-17T20:55:57-07:00http://www.firstlightastro.com/skiesabove/files/cd210ab427a2001da0ed0c6d86a3bfd3-109.php#unique-entry-id-109http://www.firstlightastro.com/skiesabove/files/cd210ab427a2001da0ed0c6d86a3bfd3-109.php#unique-entry-id-109Looking up in the night sky, away from city lights, we see myriads of stars. So did our ancestors. The mystery and majesty of the starry night impressed them then as it does many of us now. Most were driven to put sacred stories to the stars, some were tempted to worship them.

But the heavenly arrangement above is unique to our time in the history of the universe, and to our place in this galaxy of ours. The celestial painting above is ours and ours alone.

People for thousands of years assumed, understandably, that the stars above were fixed, unmoving. Many believed they were stuck somehow on a colossal sphere enveloping earth at some finite distance. The whole sphere moved around us giving the stars the appearance that they were moving in unison over our heads during the night.

We know now that they are not fixed points of light, but thousands of fusion reactors spread all about us at greatly varying – and inconceivably large - distances.

If we were to travel out into space we’d see that the constellations appear relatively the same – for a while. But moving out at greater distances, far beyond the edge of the solar system, the stars in the constellations would appear to shift about. Before we knew it, nothing in the heavens would be recognizable as any of the starry designs we see here from earth.

It’s pretty straightforward why. If you saw a forest at a distance, the trees would seem to trace out a certain pattern. Walking a little to the right or left essentially makes no difference to the pattern of those distant trees.

But walk toward the forest and the closer you get the more the trees seem to change position. The pattern you saw from a distance is no longer there. Get to the forest itself and walk in amongst the trees and whole new patterns show up continuously.

But the constellations don’t change only because of our location, they change with time, as well.

The stars we see in our skies are not the same stars the dinosaurs saw in theirs. What humans have seen above in the last tens of thousands of years is unique because of the time we are living.

One reason is that stars really do move. And some are moving pretty darn fast. But they are so unbelievably far away that it takes a long, long, long time to notice any movement at all through the background of other stars.

But give them enough time and the stars will move about, changing the starry designs as they do.

Another reason our view is unique has to do with this fact: The stars that we can actually see are the brightest available stars up there. They are the big burners, the monster stars. There’s not a tiny dim one in sight. Those little guys are numerous, to be sure, but not visible.

The stars that do light up our celestial sphere are short-lived. By their very nature they are doomed to die soon. They burn themselves up in just tens of millions of years, not tens of billions. That means that most stars alive now weren’t even born when dinosaurs ruled the earth, about 65 – 225 million years ago.

Moreover, stars visible to the dinosaurs back then were similar to ours in composition, so those ancient stars have since faded away or exploded.

T. Rex didn’t see our stars; we don’t see his.

And the stars we see in the heavens now will not be here tens of millions of years down the line. The majority of them are destined to die out by then.

New stars are being formed, to be sure, ensuring another generation of future constellations. But that scene will be different in a second profound way. There is less and less available material to build stars, therefore there will be fewer of them to light the sky. The future bodes poorly for those who love a sky full of lights.

Bottom line: All the familiarity of the night sky is familiar only to humans. Before we were here and after we are gone, and anywhere else in the galaxy, let alone the universe, a whole different sky fills the view.]]>ritter777@gmail.comNone2005-07-31T20:50:47-07:00http://www.firstlightastro.com/skiesabove/files/9fdb689e7c5d024cc322e4deab2fbf6e-108.php#unique-entry-id-108http://www.firstlightastro.com/skiesabove/files/9fdb689e7c5d024cc322e4deab2fbf6e-108.php#unique-entry-id-108As I write this we are riding a string of really hot, really humid, miserable days. These are the dog days of summer, as the saying goes. But did you know that the term “dog day” comes from the realm of astronomy?

And that it has to do with a star that’s not even in the night sky during this time of the year.

Normally the star Sirius is known as a winter/spring star. It is the brightest star in the night sky then. Only over eight light years from earth and monstrously hot to boot, it is one shiny object!

Its name is probably derived from the Greek “seiros,” which means searing. Other peoples gave her similar sounding names. The Celts called her Syr, the Greeks Osiris, and the Egyptians Cahen Sihor.

It’s the Egyptians that have one of the most revered roles for Sirius. But first a little astronomy!

Earth travels around the sun during the year. Our “daytime” is when the side we live on faces the sun. Our “nighttime” is when we are facing away from it. We all learn that in elementary school. But think about that.

Traveling a giant circle all year long means that when we are facing away from the sun - the “center” of our orbit - we are slowly exposing ourselves to new celestial real estate outside our orbit, during the night. The stars we see when we are on this side of the sun are not the stars we see when we are on that side over there months from now, or way over there six months from now.

We see Sirius in our night sky during winter and spring. But where is she now? She is on the daylight side! Unfortunately, the sun brightens the entire sky when it is up so it gets real hard to see the thousands of stars up there during the daytime. But we can cheat a little!

Sirius, being near the sun during this time of the year, will rise with it. The skies are still dark enough during early morning to catch glimpses of stars nearby the sun before full-on daylight kicks in. This phenomenon, when a star rises with the sun, has the fancy title of heliacal rising. And it was of high importance to the Egyptians.

The Nile River meant life to the people of Egypt. And its annual flooding during this time of the year was highly desired because it essentially fertilized all the land around it.

The flooding came about the same time each year, and you’ll never guess what star rose with the sun at that time. Sirius, of course! And Sirius was given the credit for the renewing of the land.

So the annual appearance of Sirius with the sun came with great hope and anticipation. The Egyptians so valued this time of regeneration that they set their calendars by it.

Dr. E. C. Krupp writes in his book Beyond the Blue Horizon, “Egypt, it was said, is a gift of the Nile, but the Nile, as far as the Egyptians were concerned, was a gift of Sirius.”

And the star played other important roles in Egyptian culture, both in their creation myths and in their myths of living and dying and being reborn.

But the Greeks and Romans had a special place for Sirius, as well.

It was in their mythical stories part of the constellation Canis Major, one the dog constellations near Orion. Sirius itself was known as the Dog Star. And it’s here where we finally make the dog connection.

Think of the Mediterranean region during the summer. It’s hot, it’s oppressive. A good time is not had by all. And during the days of the ancients hot, humid weather was not exactly a form of disease control.

And, of course, the hotter weather and all the travail that accompanied it must be due to that searing hot star that rose with the sun - that Dog Star!

Hence, the weeks around which Sirius rises with the sun are the “dies caniculares,” the dog days.

If you are an early riser you can see Sirius rise with the sun. Now understand that rising at the same time as the sun doesn’t necessarily mean at the same place. For us here in southern California, you’ll have to look to the south about 45 degrees, and there she’ll be rising above the horizon just before the sun.

After you take part in this ancient rite of observing the heliacal rising of the Dog Star, start brewing the iced tea, shut the windows, dress lightly, and prepare yourself for what’s likely to be another dog day.]]>ritter777@gmail.comNone2005-08-07T20:46:16-07:00http://www.firstlightastro.com/skiesabove/files/42f4b8ed70d83bc3bcccbb42aea43625-107.php#unique-entry-id-107http://www.firstlightastro.com/skiesabove/files/42f4b8ed70d83bc3bcccbb42aea43625-107.php#unique-entry-id-107One great thing about summer in America is that we get two fireworks shows. Both are exciting and beautiful. Both elicit “ooohs” and “aaahs” from awe-filled spectators. Both take no more effort than to look up and enjoy.

But one is artificial, the other natural. Of course, the 4th of July celebration is the artificial, man-made one. But the other can be seen all over the world in the night skies around the 12th of August.

It is, of course, the Perseid meteor shower, an annual heavenly delight for people everywhere – astronomer or not.

The meteor shower is a friendly reminder that there is not just the sun and the planets in our solar system, but asteroids and comets, as well.

The comets are the main reason for our meteor showers, including this week’s.

Comets travel about the sun on highly elongated orbits, and slough off dust and gases when near the sun. We saw some of this dusty material get exploded into space when NASA’s Deep Impact spacecraft threw a projectile into a comet last month.

But the dusty material stays in pretty much the same very large orbit as the mother comet.

If the comet’s orbit happens to cross ours, our planet inevitably smashes into the dust train. As we do, the comet dust gets thrust into our atmosphere at great speeds, 10-40 miles per second!

When just a random sand grain-sized particle flies through our beefy atmosphere at that speed it lights up from all the friction with our air molecules. That, my friend, is a meteor.

When we hit a swarm of these tiny particles, as what happens when we hit the debris train from a comet, meteors can come fast and furious. That is a meteor shower. Instead of the usual 5-10 random meteors per hour we normally get, a good shower can provide us with hundreds or even thousands per hour.

The Perseids originate from the jetsam of Comet Swift-Tuttle. Its latest fly-by was just over a decade ago, and at the moment it is very, very far away. But although the comet proper is presently way over yon, we are passing through its debris train now!

You may have already seen a Perseid meteor – we are already in the outer edges of the trail of schmutz. But the time to really make time for them is either the night of the 11th or the 12th. It is then that we pass through the thickest parts of the dross, kind of guaranteeing a fairly good fireworks show. But it’s never a sure thing.

The predicted peak is Friday night, a good night since most need not worry about school or work the next day. And, more importantly, the Moon will be setting about midnight, right before Prime Time for Meteors begins. Yes, sorry, I said after midnight.

The reason the best time for meteor showers is after midnight is because that is when our location on earth turns full face into the cloud of crud. Imagine sticking your head out the car window while being driven through a light rain. Face backwards and your face feels nary a drop. But turn around into the direction you’re being driven and, ouch! its full immersion time.

How many you see will also depends on your viewing conditions. Are you in the city? You’ll see the bright ones, but that’s it. Out where its dark with no interfering man-made lights, and with few hills or trees surrounding you? Then you may see one every couple minutes.

Best for all, you need not be an astronomer to enjoy it. You do need a place to observe them; lay down for maximum comfort. You need to smear on the DEET before you go out - West Nile virus is no fun I hear. And even if it’s warm, dress in layers. It will get cold later even on a hot night.

But because the meteors during a shower never hit the ground, you needn’t worry about bringing along one piece of equipment: an umbrella.

Clear skies!]]>ritter777@gmail.comNone2005-08-14T20:38:32-07:00http://www.firstlightastro.com/skiesabove/files/88ebff984101ac181fb9b6cae9257dc1-106.php#unique-entry-id-106http://www.firstlightastro.com/skiesabove/files/88ebff984101ac181fb9b6cae9257dc1-106.php#unique-entry-id-106School is back in session, or about to be. And you or your child might be soon hearing the words, “And what did you learn over the summer?”

That Jennifer wants Brad back? Yawn. That gas prices soared. Boring! You need something smart and astronomical to fill this order. Never fear! Here are some quick trivia to impress both teacher and fellow students alike. Read them, know them, and go back to school mentally dressed to impressed! Here goes…

1. You learned that the big star-like object now in the western skies after sunset is Jupiter and it’s bigger than you ever imagined!

Jupiter, the 5th planet out, is so monstrous that it outweighs all the other planets combined! One can mix together all the planets, Mercury to Pluto, and still couldn’t make anything as massive as that Big Guy out there. And yet to see it, that bright lone dot in the sky, gives one an idea of how vast space really is. Our solar system, although huge, is vacuous beyond words. You might say it is nothing more than space, interrupted now and then by a seemingly random rock.

2. You learned that there is a vast reservoir of planet-like things out beyond Pluto!

Most of us learn of the nine planets, and their order, but very few of us are aware that beyond the common planets lies a dispersed collection of crud that extends for billions of miles still. Here are thousands of icy bodies in a donut-like area called the Kuiper Belt. It is here that astronomers working at Palomar have found icy bodies considerably bigger than Pluto! Will they be deemed planets, as well? Or will they keep their present non-poetic names of Kuiper Belt Objects? Will Pluto itself be downgraded to a mere Kuiper Belt Object? Stay tuned, the next year should be a telling time in the planetary sciences.

3. You learned that Mars is rising earlier and earlier in the evening, readying itself for a close approach in October.

As we pass Mars on our inside lane round the sun we will come closer to it, to be sure. It will get brighter and brighter in the night sky, it’s bright pinkish color setting it apart from the background stars. But unlike the internet stories being forwarded all over, the Red Planet will not be as bright and big as the full Moon! Nor will it pass so close that we can see the ice caps and dust storms with the naked eye. We’ll still need a scope to see those – sorry!

4. The whole classroom, the students, the books, the backpacks – even the teacher! – are made of atoms forged in the furnaces of giant stars that lived and died before our sun was even a thought in its parents’ minds.

You may recall from previous columns here that the great giant stars live and die a wild and crazy life. Their immense mass, sometimes a hundred times that of our own star, have such intense gravity that their innards get squished something frightful.

It’s OK! This pressing causes a process called fusion. Fusion “fuses” little hydrogen and helium and carbon atoms into bigger atoms. Fusion lights the great flaming plasma and pushes the gases back against gravity into a bright sphere that we see as a “star.”

But the big stars can only fuse to iron. Once iron is formed the process stops producing energy to balance the mighty crush of gravity. Gravity doesn’t care; it continues to push down anyway. In a complicated set of steps the star’s core collapses and explodes violently.

The violence is so intense that the atoms already there are fused further into essentially the entire Periodic Table, and thrown out into space.

Future star systems collect this debris into new stars and planets.

So, not only is our planet proper made of stardust, so is everything in it. That would include you and your backpack and the classroom hamster, Larry.

There! That should impress the teachers for a while. But don’t stop there! Go and discover more throughout the year, filling yourself not just with knowledge, but with understanding and appreciation for this marvelous universe we’ve been given.

Have a great school year!]]>ritter777@gmail.comNone2005-09-05T21:35:15-07:00http://www.firstlightastro.com/skiesabove/files/ecd6e3e13492d5ba6905082f0bc618a1-105.php#unique-entry-id-105http://www.firstlightastro.com/skiesabove/files/ecd6e3e13492d5ba6905082f0bc618a1-105.php#unique-entry-id-105Tonight there’s likely to be a bluish-white Vega parked right outside your house. Go ahead and step out and look to the left or to the right; you won’t see it. You’ll have to look up – straight up.

Almost directly above your heads during this time of the year is a bright star in the constellation Lyra. It is Vega, derived from the Arabic name of the constellation, Al Nasr al Waki, which means Swooping Eagle. Philologically speaking, Al Nasr al Waki begat Wega. Wega begat Vega. And there you are.

Let’s look under the hood of this star and see what makes it run.

Vega is 25.3 light years away, about 150 trillion miles as the crow flies. But that’s actually pretty close considering our galaxy alone is well over 100,000 light years across! Why, Vega’s almost a neighbor.

Vega is just over three times the size of our sun. That works out to a good 2.8 million miles through, which is one hefty bag of plasma. It’s all this extra mass that makes it burn a whole lot more efficiently than our own sun.

As a result, Vega gushes more than 60 times the energy that our star does, and a lot of that energy is from the destructive ultraviolet side of the electromagnetic spectrum.

Stars similar in brightness to Vega join her in making up the distinctive Summer Triangle. Bright Altair and Deneb both round out this pointy asterism that can be seen high in the heavens for a couple more months.

Vega also has the distinction of being the first star photographed by Earth-based paparazzi. In 1850, William Cranch Bond and John Adams Whipple, in a day when it was apparently stylish to use middle names, were the first to image the starry object.

On the night of July 16/17 they photographed Vega with the telescope at Harvard Observatory using the early daguerrotype process. But Vega was not content with that brief bit of notoriety. Over 100 years later, she would play yet another leading role in astronomical imaging.

Vega rotates, as all stars do. But we see it pole-on, looking down on it as it spins. New, improved images of Vega reveal to us that the star is surrounded by… well, a whole lotta crud. Since 1983 we’ve been looking down at the full face of a big dirty spinning Frisbee, with bright Vega right in the middle of it, as if she were brooding over a solar system in the making.

And just recently it was discovered that some of this crud is being blown away by the solar winds of the mother star. This present sweeping implies there was a recent rocky collision there. Could it be that two young planets, possibly the size of Pluto, have recently collided and vaporized into massive clouds of dust?

And the fate of Vega? Because it is such a big star it will exhaust its fuel much faster than our star. It’s really only a relatively young stellar object – 350 million years old, plus or minus – considerably younger than our 5 billion-year-old sun.

But according to present theories of star formation, Vega will retire from stardom in about 650 million years, fizzling out into a nondescript white dwarf. It will be lucky if it sees its one billionth birthday.

But before she fades away Vega will go out with at least one more crowd pleaser.

Because the Earth wobbles slowly on its axis, the North Star is not always the one we see now, which is Polaris. In about 10,000 more years we will have wobbled around enough such that the new North Star will be – you guessed it! - our star of the month, Vega.]]>ritter777@gmail.comNone2005-09-19T21:32:24-07:00http://www.firstlightastro.com/skiesabove/files/a23082d3019955b8fa5af9fe064b15c8-103.php#unique-entry-id-103http://www.firstlightastro.com/skiesabove/files/a23082d3019955b8fa5af9fe064b15c8-103.php#unique-entry-id-103Of all the big four seasonal dates - the winter and summer solstices and the spring and fall equinoxes - the fall equinox falls under “Most Ignored.”

Winter solstice, the shortest day of the year, is famed throughout the world in nearly every culture and is celebrated in a wide variety of festivals. Summer solstice is the longest day of the year, marking our first day of summer, a high holiday for most American school kids. The spring equinox denotes for many the end of winter, and the beginning of both new life, and the allergy season.

But most of us pass right by the fall - or autumnal - equinox with nary a notice. So our column this week is dedicated to this unsung seasonal date that we will celebrate on the 22nd. It’s time the equinox got equal time.

So what is this fall equinox all about anyway?

Our planet, as you learned in school many years ago, travels around the sun in a nearly circular orbit. And we all know that the Earth spins with a slight tilt to it.

Well, we spin about smoothly enough on our axis each day, almost like the perfect top, and revolve slowly and effortlessly around the sun year after year. But what confuses some people is that our planet always has its spin axis pointing in the same direction – all year long. For us in the northern hemisphere, our pivot point points towards Polaris, aka The North Star.

At winter solstice we in the northern hemisphere are tilted away from the sun. Therefore, we have shorter days and cooler temps, and the sun hangs low in the sky.

The summer solstice is when we are tilted most toward the sun and it starts to get noticeably hot and the daytime is longest.

But right between those two days, once in March and once six months later in September, we are tilted neither towards nor away from Sol.

The September date is this Thursday. Since we are not tilted with respect to the sun, our “daytime” will have 12 hours with the sun being above the horizon, and 12 hours when it will be below. Hence the term equinox, from the Latin æquinoctium, from “æqui” meaning equal, and “nox” meaning night, inferring equal times of day and night.

Because the earth is standing at virtual attention to the sun, there will be light from pole to shining pole. That means essentially everyone on this planet will get 12 hours of sun up, 12 hours of sundown. It is an equal opportunity day.

But the equinox is more than just 12 up, 12 down.

The sun on this day rises due east and sets due west for everyone. And I mean the real east and the real west! None of that funky compass stuff.

The compass faces toward a magnetic North Pole, which is not true north for just about everyone on Earth. Thus, neither is the “E” of the compass true east, nor its “W” true west.

But on the day of the equinox, if you have a nice flat horizon you can mark true east and true west truer than any compass by observing exactly where the sun rises and sets.

Now I sort of didn’t tell the whole truth when I told you that all people on earth would get 12 hours of sun up, and 12 hours of no sun. There are two places that are exempted here. Can you guess what those places might be?

I’ll give you a hint. At the equator, one will see the sun rise due east, travel straight up over head then straight down, and set due west.

Here in southern California we will see it rise due east at an angle, sweep over the southern skies at noon (only about 57 degrees above horizon at its height), and set at a sharp angle due west.

Higher north in Canada the sun rises due east, and sharply cuts through the low southern skies, setting 12 hours later due west.
Any ideas yet of where the sun neither rises nor sets on this day?

At the poles. At the North and South poles, the sun will not rise or set! One standing there will actually see the sun just skirt the horizon in a giant circle, never rising nor setting.

For us who live here in southern California it would be a quite a strange sight indeed!

Here are some things you can do Thursday.

In the morning you can mentally mark the place on the horizon where the sun rises (assuming no hills!) and truly call that East. Twelve hours later you can see where it sets, again assuming a flat horizon, and mark that as West.

Then watch in the next weeks as we head toward the next seasonal marker, the winter solstice, how the sun rises more southerly, moves lower through the sky, and sets more southerly. All this means less sunlight, lower temperatures, a lower sun, and more annoying sun-in-the-eyes on your drive to work.

Have an awesome equinox!]]>ritter777@gmail.comNone2005-10-02T21:26:52-07:00http://www.firstlightastro.com/skiesabove/files/f988012335d73b18770f0b5be8415893-101.php#unique-entry-id-101http://www.firstlightastro.com/skiesabove/files/f988012335d73b18770f0b5be8415893-101.php#unique-entry-id-101Hurricanes. Can’t live with them, can’t live without them.

Hurricanes have gotten a bad rap lately for obvious reasons. Two big reasons are Katrina and Rita, the two latest hyper-destructive cyclones to hit our country. And more are probably on the way, if not this year, then the next, and the next…

But if we look closer at them, we might come to a conclusion that they really aren’t that bad. Put down those torches and pitchforks! Let me put a positive “spin” on hurricanes…

Our planet spins and spins, all the live-long day. It is because of this spin that we have the giant ocean currents that swirl around the Atlantic, and the overall nice weather that our friends in the south enjoy and which attracts millions of tourists annually.

As the warm waters of the ocean currents around the southern latitudes cycle up toward the north, they can spawn hurricanes. It seems now that the warmer the waters, the faster the currents. And the faster currents lead to more terrifying hurricanes.

It appears that this all occurs in an oscillating kind of way. Meaning that we are in a heavy hurricane period - now. But the 1970’s through the early 1990’s saw lower temps and fewer monster ‘canes. Before that, from about the mid-1920’s to the late 1960’s, it was warmer and nasty hurricanes were more numerous. As far back as we’ve recorded, heavy hurricane decades appear to come and go.

Bottom line for the moment: We are probably in a time of higher hurricane numbers, and they may be bad for some years to come.
So how can any of this hurricane stuff be good? How is it we “can’t live without them”?

Few of us have thought through what it would be like if conditions were not ripe for hurricanes.

For example, what if the world were spinning even faster? What if our day were just a few hours long rather than the 24 hours it is now?

Early on in the history of our planet, we probably had 5-10 hour days. The earth spun quicktime to say the least. Spinning this fast meant that we had winds, severe winds, all the time. And I ain’t talking the wimpy Santa Ana type or even the slightly-less-winpy Katrina kind.

An astrophysicist friend of mine calculates that in those early days the winds swept over at hundreds of miles an hour - if not over a thousand – all the time.

We see tremendous wind speeds like this on the “gas giants” in the outer solar system. Those planets out there, all of them, spin fast. Neptune’s winds average over 2000 miles per hour.

Now, you can fly one mean kite under these conditions, but you will not enjoy life on a planet with winds that can tear your hair off your head.

And the weather patterns on those planets are confined to narrow bands across the face of the planet. This is hardly the lazy ebb and flow of high pressure and low pressure systems we see the local weather guy trying to explain on the 6 o’clock news.

If our spin rate were slower, if our planet took 30-40 hours or more to slooooowly spin around, things don’t get better.

We may avoid ideal hurricane conditions of today, but there would be other, much more severe, things to worry about.

Imagine having the sun up for more than 20 hours at a time, heating the equator and mid-latitudes to a fare-thee-well.

Just as bad, the sun would be gone for about the same amount of time, our stored heat now flowing out into space with nothing to replace it, thus cooling us way, way, down.

Each “day” we would experience extreme temperature fluctuations.

Right now our spin rate allows us a blessed midway between the extremes. Our planet spins just fast enough that weather systems can sweep nicely across the face of continents, delivering alternating times of life-giving rain and sunshine for much of the planet.

Not too fast a spin, not too slow… but just right for a tremendous amount of ideal living space.

And, let’s be honest, hurricanes hardly pop up at random spots over the globe. The real estate they claim for themselves is pretty well established. We know their favorite haunts and, thanks to modern technology, we can track them as they meander across the Gulf. This, ideally, gives people who choose to live in such vulnerable areas ample time to prepare or evacuate.

And lest you think I’m harshly judging the people of the south for choosing to live in a veritable parking lot for hurricanes, I myself have chosen, with full knowledge, and under no duress, to live in a part of the country ripe for earthquakes.

Even though hurricanes seem like natural evils - and to be sure they can bring much pain - I might argue here that they are a relatively minor price to pay in comparison to what “might be.”

A hurricane is, for me, another awesome and terrifying reminder that this planet we live on, this rock we call our home that literally bursts with abundant life, is an amazing work of just-right art.]]>ritter777@gmail.comNone2005-10-16T21:21:41-07:00http://www.firstlightastro.com/skiesabove/files/0e78d94c3a0ac005540e3c6a3fad8071-100.php#unique-entry-id-100http://www.firstlightastro.com/skiesabove/files/0e78d94c3a0ac005540e3c6a3fad8071-100.php#unique-entry-id-100Quiz Time! The following statements are true or false. Ready?

1. It’s easy to spot Mars in the sky. It’s the only red thing up there!

Mars is known as The Red Planet. And as we’ve seen from all those pictures coming in from those tiny spacecraft traveling about the planet, it does indeed take on a reddish hue. A lot of the surface of Mars is made up of oxides of iron, similar to rust. Hence the ruddy look.

But it isn’t really too red in the sky. In fact, it barely makes pink. But it has enough of a tinge of red that we can still call it the red Planet and not lose sleep about it.

But it’s not the only red thing in the sky. Stars can be red, too! It all depends on their temperatures.

In astronomy really hot stars bleed all the wavelengths of light but really pour out the blue, cooler stars appear white and yellow (like our own), and the coolest stars only get to red.

It’s the small stars, the runts of the cosmic family, that can’t raise their surface temps too high. They can’t fuse a lot of material down in their cores and therefore never really cough up enough energy to heat the place up too much.

But there are monstrously big stars that are red, too. How’s that??? The bigger stars, when they reach the end of their lives, expand to enormous sizes. You may remember from school that when gases expand they cool. As these monsters outmonster themselves, their surfaces cool. As they cool they change color, many eventually reaching redness.

There are several of these “red giants” visible in the skies, one of which is Antares in Scorpius. What an amazing coincidence! Antares means anti-Ares, rival of Ares. Ares was the Greek version of the Roman god Mars. Antares is named so because it is often confused with our friend Mars.

So the original statement is false. Mars isn’t really that red, and there are many other things in the sky that are actually redder.

2. It’s only in the last couple centuries that people have known that the world isn’t flat.

There were these people who lived more than 2000 years ago called the ancient Greeks Some of them liked to sit around all day and think… and think… and then think.

Some of these guys thought about this: Why is the shadow of the earth on the moon always round when there is a lunar eclipse. Well, they thought, what always makes a round shadow? Hmmm…

A sphere of course!

There were a lot of other evidences, too. But the point is, they knew earth was round. They even figured out its circumference, the distance around, without even going around the planet.

Most educated people since those ancient times thought the world was spherical. The uneducated folks often thought the world was flat because… well… it sorta looks that way!

But that we just recently discovered the planet is a big ball is a big myth.

3. The Milky Way we see in the sky and the Milky Way galaxy we live in are the same thing.

Throughout the year, but especially during the summer, there appears in a dark unpolluted sky, a band of light called the Milky Way. It is the source of a thousand myths from peoples all over the world.

But it wasn’t until Galileo’s time that it was discovered that that great band was actually a great field of stars. Peering into the belt with a telescope one can see countless tiny stars of all colors.

And it wasn’t until the beginning of the 20th century that it was discovered that there were other galaxies in the universe, distant monstrous collections of billions of stars each! We were just one galaxy of billions!

It turned out that Great Band of light we called the Milky Way was – ahem - us.

How can it be that we can see countless spiral and elliptical and irregularly-shaped galaxies all over the place filled with billions of bright stars each, but we can only dimly see our own?

To view our place in our great spiral of stars imagine wading in a harbor filled with hundreds of boats. Above you is sky, below you is water. It seems the boats are pretty much limited to a band surrounding you.

In space we have a clear view above the spiral and a clear view below, but in the spiral, where we live, there are literally hundreds of billions of stars, like the boats in the harbor.

Well then, since we are drowning in stars, the whole place should be lit up! Well, there are lots of stars to be sure, but there is also a truckload of dust up there. The dust blocks a lot of the light from ever reaching us.

So, to conclude, the Milky Way we see in the sky and the Milky Way galaxy are the same thing – our amazing home.

How did you do this time? Are there questions you would like to see here? Write me with them!

Until next time, clear skies!]]>ritter777@gmail.comNone2005-10-30T21:17:09-08:00http://www.firstlightastro.com/skiesabove/files/15520628f32b57fcf05b81bca892962b-99.php#unique-entry-id-99http://www.firstlightastro.com/skiesabove/files/15520628f32b57fcf05b81bca892962b-99.php#unique-entry-id-99After all the internet hype a couple months ago about Mars appearing “as big as the Full Moon,” and then suddenly vanishing, I fear the truth about our Little Red Buddy’s latest close encounter may be a little… uhhh… anticlimatic.

I’ll risk telling you about Mars anyway, without all the urban legend embellishments, and bruit proudly of the truth about that bright pink dot gracing our evening eastern skies.

Mars, as you know, is our fourth rock from the sun. A tiny rocky planet, it is only about half the size of our own.

Of course there are other rocky planets in our neighborhood but they’re tough to examine .

Mercury always hugs the sun, so it’s difficult to see in all the brightness. Venus is big and bright to be sure, but she is cloud-covered all the time.

Mars, on the other hand, has a load of features on its surface, and there is no better time to espy these than now - at opposition.

Opposition is when a planet is on the opposite side of the sky as the sun. As the sun sets, the planet rises and thus stays in the sky all the live-long night. From a big picture view, we in our orbit have finally caught up with Mars in its orbit. Which means not only is the planet up all night, but we are at our closest approach to it, as well.

These are two things that get the astronomer’s heart beating just a wee faster.

And as an added bonus, on this fly-by we are closer to Mars than usual. What do I mean by “usual”?

Mars’ orbit is not exactly a perfect circle. It’s actually rather elliptical, like the rim of a drinking glass seen at an angle. This means that sometimes Mars is close to the sun – what astronomers call perihelion - and sometimes it is far, aphelion.

Well you can imagine then that the best time to be near Mars is when Mars is nearest to the sun. We can just about shake hands as we pass by. It is then we get a fine close-up look at our little friend.

We were just about as close to Mars as we can get the last time we flew by the Red Planet. That was in 2003. But even though we aren’t now at the absolute closest we can get – Mars is just a bit away from perihelion - we are close nevertheless.

What also makes this year’s opposition so good is good position in the sky. Meaning this: We are at the time of the year when the sun is creeping lower across the sky, and the time when the planets at night will do the opposite. They will rise high in the sky. The benefit?

This means a planet will be high above the heat waves, off the horizon. There will be good “seeing” as we say in the biz.

So you will be able to see more clearly all those features that we’ve been watching for the last 400 years.

Get out a scope and scope out for yourself Mars’ polar ice caps. And see the dark areas in contrast to the light areas. When you do so you’ll be seeing history.

For the last part of the 19th century and far into the 20th century many thought that those dark areas were vegetation and that the polar ice caps were made of water. This, together with some vivid imaginations that saw non-existent canals strewn across Mars, made many people think that Mars was filled with… well… Martians!

So grab yourself a scope or get together with an astronomy club and go take a look at the Red Planet in the next couple weeks.

If you’re a glutton for punishment and want to see Mars when it’s at its most distant opposition, you’ll have to wait until the year 2832. March to be exact. Mark your calendar!

Until next time, clear skies!]]>ritter777@gmail.comNone2005-11-16T21:14:45-08:00http://www.firstlightastro.com/skiesabove/files/7f5623a8b9685cde1dfe4b91a8bdfabe-98.php#unique-entry-id-98http://www.firstlightastro.com/skiesabove/files/7f5623a8b9685cde1dfe4b91a8bdfabe-98.php#unique-entry-id-98Let’s focus on the sun this week!

Many of us look at the sun but few of us ask questions about it. Questions like: If it’s a ball of gas, why can’t we see through it? Where does all that heat come from? Is it really made of cheese? Oops! - wrong heavenly body.

Well, let’s start with where the energy source is. We know from experience that most hot things cool down when left alone by themselves. Take a red-hot poker out of the fire and set it aside and it cools down.

So why doesn’t the sun cool down? How does it stay hot? The same way you do. It has its own internal energy source. Only the sun doesn’t consume fuel to heat up, as we eat food and metabolize it. The sun fuses for its energy.

Way down deep inside, at the center of the sun called the core, the temperatures and pressures are intense to say the least. There, little hydrogen nuclei – the most prevalent element in the sun by far – get crammed so close together (high pressures) and move so fast (high temperatures) that they do things there that they would never dream of on earth.

These tiny little critters actually smash into each other and stick, in a series of events called fusion, producing helium as they do. But here’s the real important part: As they fuse, some of their mass turns into energy! I kid you not!

According to Einstein’s Special Theory of Relativity, mass and energy can be turned into each other. And that’s what’s happening in a fusion reaction, mass becomes energy.

The sun fuses about 600 million tons of hydrogen every second! About 4 million of those tons become pure energy. The rest becomes helium.

But the energy doesn’t now just have a free ride out of the sun, no siree bob!

Remember the pressure is intense, the atoms there are packed tight, so the newly formed energy- in the form of photons – doesn’t get far before being absorbed by some other particle. But not to worry! It gets re-emitted immediately in some random direction! But only to be reabsorbed again!

This process repeats itself countless times. The photon though, because of pressure differences, finds it easier to move gradually out towards the edge of the sun. But you’ll never believe how long it takes to reach there.

That lowly high-energy photon created way down in the core bounces about for millions of years until it finally gets its release papers!

This is why we cannot see through the sun. There is just too much stuff there absorbing light. But then why and when and where is the little packet of energy released???

If you could travel from the intensely hot, high-pressure core of the sun to its outer layers, you’d find the pressures getting lower and lower and lower. That means the “stuff” is packed less and less and less tightly.

A photon finally gets to a part of the sun where there is… nothing... blocking… its… path! Why, it suddenly finds that it is free to leave. And leave it does!

This release zone on the sun is called the photosphere. It is what we normally refer to as “the sun.” The big yellow ball we see up there is merely the first layer that allows light to flow out. There are actually layers above that – the chromosphere and the corona – but they are mostly invisible to our eyes except during an eclipse. And although those “invisible” layers are legitimate parts of the sun, for most of us “the sun” ends at the photosphere.

Now that the photon is free to leave it races out into space at about 186,000 miles a second.

Sadly some of these photons, after spending all that time making their way through the sun, break free, and just a little over 8 minutes of freedom later find themselves approaching a blue-green-white planet. They race through the atmosphere and in an instant are annihilated as they crash… onto your head.

The same thing happens in stars tens or hundreds of light years away. Their photons struggle to get through the stars. They finally break free, spend a couple hundred years racing through empty space, only to crash into the back of your eye, sending a message to your brain. And you elicit the response, “What a pretty star!”

C’est la vie, little photon.]]>ritter777@gmail.comNone2005-11-22T21:11:21-08:00http://www.firstlightastro.com/skiesabove/files/d85cde2536d28c169e28ea82f053dd21-97.php#unique-entry-id-97http://www.firstlightastro.com/skiesabove/files/d85cde2536d28c169e28ea82f053dd21-97.php#unique-entry-id-97Thanksgiving is meant to be a time of giving thanks, of looking back at the year and seeing the big picture, of realizing that even though some things didn’t go as planned, overall there was a lot to be grateful for.

But around the globe this year humans have had a tough time. We have experienced devastating tsunamis, cataclysmic earthquakes, and a row of catastrophic hurricanes. “Without doubt this planet is unleashing its fury on us. And surely that is nothing to be thankful for.”

Let’s look deeper.

Most of this year’s natural disasters occur from surface phenomena. The earthquakes are the result of the great tectonic plates creeping across the face of the earth. And most tsunamis result from undersea shifts in these giant plates, with great ruptures displacing massive amounts of water. This disturbed water radiates out spreading the energy over huge areas sometimes with calamitous results.

Atmospheric phenomena like hurricanes and tornadoes can partially be attributed to the spinning of the earth. The spinning causes great movement in sea and air that combine to form the great lethal cyclones.

How can these characteristics of earth be anything to be thankful for? Well, I might argue for one that those great massive moving plates are actually a godsend to this planet.

They move because the planet underneath them is somewhat liquid-like. The great solid plates – like the North American Plate or the Pacific Plate – float and move about on this semi-liquid.

And this drifting about at just inches a year, which is not too fast, not too slow, gives us mountains and valleys and all the geographical array of surface features we see and enjoy and that promotes life’s profound diversity.

The plates are just thin enough that this can happen. Thicker and they wouldn’t be able to move and crack and the planet would eventually erode into a smooth sphere. Thinner and there would be an incessant parade of nasty volcanic explosions and destructive earthquakes all over the planet.

No other known planetary body has just the exactly right conditions for this amazing plate movement.

And the spin speed, covered in an earlier column, is just right, too. We spin faster and winds become devastating. Slower and the day-night temperature differences become unbearable.

And it is not just those several characteristics that cooperate to give us this Home of ours. The tilt, the distance from the sun, the type of star we orbit, the number of suns we have, our magnetic field, our extraordinary atmosphere, the amount of water on the earth and above it, our overall size and gravity, our nearly circular orbit, and many, many, many other characteristics make this a planet nonpareil.

But all these, as perfectly designed and coordinated as they are, don’t guarantee we won’t be without tragedy. For example, having so much life-giving water on this planet is an absolute blessing. But people may drown in it. Should we curse the water because of that? Obviously not. The same goes, in my opinion, for all the rest of the properties of this planet that leave a door open for disaster.

One challenge I have given my astronomy classes is to conceive of a planet more perfect for human life. I have not heard anyone ever give me anything that could be considered an improvement on what we have been given in Planet Earth.

Moreover, I might opine here that even in natural disasters there may be something to be thankful for. It is then that the best amongst us, the most courageous, the most heroic, come forward. There are few times when more people become more interested in selflessly helping those around them than when tragedy strikes. I don’t know about you, but observing unconditional love in the face of mass destruction makes me extremely thankful.

And it isn’t like we haven’t been warned. We can be very thankful for advances in modern technology that help us to see hurricanes coming, and determine when a volcano is about to blow, or tell us where earthquake faults may lie, or when to head for the hills as a tsunami approaches.

And it is hard not to blame ourselves for disobeying one of the basic maxims concerning the natural world around us. “Do not build your house on sand” is a simple, yet profoundly wise saying. Sand in itself is a great thing, but it is no place to build a house. And those of us who heed that warning suffer less when whatever disaster finally hits.

Need evidence? Compare the death tolls in countries with strict building codes against those with few or none when a big earthquake strikes. There is no comparison.

Yes, this year we have been hit with some high-profile calamities, to be sure. And we will get more next year, and the next. But we do live in the best imaginable place in the known universe.

And that is great reason to give thanks this Thanksgiving.]]>ritter777@gmail.comNone2005-12-11T20:53:35-08:00http://www.firstlightastro.com/skiesabove/files/48d3ce395e07bf95db34f4b5b34c6d4a-96.php#unique-entry-id-96http://www.firstlightastro.com/skiesabove/files/48d3ce395e07bf95db34f4b5b34c6d4a-96.php#unique-entry-id-96When I was taking astronomy in college my textbook had nothing much to look at but some really bad photographs of stars and some cheesy drawings of phenomena yet to be imaged. That was a while ago. Things have changed dramatically since, to say the least. Space images today are magnificent works of art.

Wanna see some?

There has been a staggering improvement in the last couple decades in the ability to image space objects. Charge-coupled devices, aka CCDs, have taken the place of film in space photography. They allow us to capture digital images in a fraction of the time it took to expose photographic plates.

Adaptive optics (AO) are newfangled computerized devices placed on telescope imaging equipment to get rid of the distortion caused by our atmosphere. Of course, those telescopes out in space need no such equipment and have been taking crystal clear images since the 1990’s. But, boy, what a difference they are making down here.

And we are no longer limited to just the visible wavelengths of light. We can “see” in just about every part of the electromagnetic spectrum nowadays, from lethal gamma rays all the way over to the harmless radio wavelengths and everything in between.

But where can we see these resplendent images?

They are all over publications such as Astronomy Magazine and Sky & Telescope. But you can also find them online - all over the web.

Starting in the so-called visible wavelengths, those we can see, you might begin your journey at the Hubble Space Telescope sites - hubble.nasa.gov, hubblesite.org, and heritage.stsci.edu. After a disastrous debut in the early 90’s, the Mighty Hubble got fixed. Here are archives of some of the most spectacular sky shots ever made. Be prepared to be awed.

There is another site that can take you on a journey through all our solar system. It is the by-product of all the NASA/JPL spaceflights made over the decades. This reservoir is absolutely filled with images from all the planets, their seemingly countless moons, and a host of other solar system debris. It is called the Planetary Photojournal and can be found at photojournal.jpl.nasa.gov.

A similar site, not as extensive, but arguably more easily understood, is The Nine Planets Solar System Tour at www.nineplanets.org.

But why stop at visible wavelengths? There are whole new worlds up there, unseen with human eyes.

The universe in infrared can be seen at the Spitzer Telescope site - www.spitzer.caltech.edu. Here you can get a little lesson on what seeing in infrared is all about, and then take some looks at seemingly ordinary parts of the sky and see how they brilliantly light up when seen with IR eyes.

One the other side of the spectrum is the strange world of x-ray astronomy found at Chandra X-Ray Observatory - chandra.harvard.edu. No pictures of bones or teeth here. Just superdeadly supernovae and supermassive blackholes.

Want to see the sun without burning your eyes out of their sockets? Go to the spectacular site of SOHO, The Solar and Heliospheric Observatory - sohowww.nascom.nasa.gov. Find here images of coronal mass ejections and solar flares and sunspots – and star-crossed comets crashing to their deaths.

Super-detailed images of sunspots, so detailed and large you feel you could fall into one, are found at a Swedish site, The Institute for Solar Physics - www.solarphysics.kva.se. But bring a rope, you just might fall in after all.

And there are images of our own planet, of course. But I cannot describe how jaw-dropping these images are; to do so would require a language not known to man. They can be found at the NASA Earth Observatory - earthobservatory.nasa.gov. I’m a little embarrassed to say I have spent hours and hours there just staring at the images of our beautiful planet – volcanoes, coastlines, hurricanes, mountain ranges, cities… Sigh…

You can see images of great telescopes themselves, and how they work, along with galleries of their images at sites like those for the twin Gemini Telescopes - gemini.edu – and, of course, our very own Classic on the Hill, Palomar Observatory - www.astro.caltech.edu/palomar.

But perhaps the most profound collection of astro images can be seen at the web workhouse of all images celestial, Astronomy Picture of the Day. As implied in the name there is a different image everyday, covering the entire spectrum of astronomy, with small descriptions and links for each. And there is an archive for all past thousands of images and a search tool for finding your favorite object.

And then, after surveying these amazing images, you and your family can sit down and have a philosophical discussion on why it is that mere collections of gas and dust can be considered “beautiful things,” and why they move us so.

Need I say anything more? No, I think you’ve got the picture.]]>ritter777@gmail.comNone2009-06-01T19:41:53-07:00http://www.firstlightastro.com/skiesabove/files/4fa067f91be986a28089c49e095e6b0a-95.php#unique-entry-id-95http://www.firstlightastro.com/skiesabove/files/4fa067f91be986a28089c49e095e6b0a-95.php#unique-entry-id-95The nighttime is the right time for seeing planets this month - the whole night through. Whether you go to bed early, get up early, or get no sleep at all, there are planets on parade all through the dark hours in June. Let's start our survey in the early evening.

Saturn is in its last act for this year. The great ringed planet is on its way around the sun to the other side. You can find Saturn in the western skies after sunset. Here's a little help: In the 8 o'clock hour go outside and face southwest. Estimate about two-thirds up between the horizon and the point over your head. Saturn is the golden star-looking creature there. If you know your constellations, it is on Leo's hindquarters.

Try and get a telescope this month to take a gander at Saturn. In the next month or so it creeps closer and closer to both the sun and the horizon, both of which severely impede our attempts to view celestial bodies.

For the night owls amongst us, Jupiter wakes from its sleep in the east after one in the morning. And as June moves along and we get into July and August it will rise earlier and earlier. You cannot miss it coming over the horizon. But if you are trying to see it through a scope, wait, if you can, for a few hours until it rises above the annoying horizon.

Bonus planet: You can see Neptune this month much easier than at most times by using nearby Jupiter as a guide.

Neptune leads Jupiter through the sky, staying just ahead of the Giant. With a steady pair of binoculars you can spot Neptune just to the northwest of Jupiter. With a telescope you can see the bluish disk of the ice giant. I have a star chart and a movie of the two planets dancing through the skies for the next month and a half with each other.

Here is the starchart for Neptune and Jupiter.

Here is the movie. (Starts 1 June, every frame equals one day)

Now a special treat for the early morning risers: There seems to be some sort of terrestrial planet general meeting going on this month in the eastern skies.

You may have noticed, if you are up before sunrise, the brightest of all planets, Venus, rising in the east. She's an easy one to spot. But have you noticed next to her Mars, the tiny pinkish dot? They are our morning stars, so to speak, and they will be joined on the 19th by tiny Mercury and a beautiful crescent Moon.

Mark your calendars for that date. You will get to see, in the same patch of sky, Mercury, Venus, Mars, the Moon, and even the Pleiades as a starry guest star.

Here is the starchart. (5AM 19 June)

June is a planet-filled month. Try and make an effort to spot a few.

]]>ritter777@gmail.comNone2005-12-27T20:35:14-08:00http://www.firstlightastro.com/skiesabove/files/d8af522748629db9e6c56a2ccd35818b-94.php#unique-entry-id-94http://www.firstlightastro.com/skiesabove/files/d8af522748629db9e6c56a2ccd35818b-94.php#unique-entry-id-94What an extraordinary year it has been in astronomy! It seems that each year - with the development of new ways of imaging and the launch of new satellites and space probes - our knowledge of the universe and its workings seems to expand exponentially.

Here’s a brief lookback at the great year, followed by an encouraging nudge for you yourself to have a great 2006, cosmologically speaking.

This year was a tremendous year on all astronomical fronts, but especially for those investigating our own backyard – our solar system. Here we delved deep into comets and asteroids and planets and moon and rings. Oh my!

Astronomers spent an absolutely mind-numbing amount of time on and around two familiar planets, Saturn and Mars, and the results were wondrous.

The Cassini spacecraft buzzing around Saturn sent back images that made you believe you were in orbit with it, just skimming by Saturn’s rings and icy satellites. But imaging countless moons and those beautiful rings was just part of it. Cassini also dumped its probe, Huygens, to land on mysterious Titan, the giant moon of Saturn. See a year of images and results at saturn.jpl.nasa.gov.

The tiny twin rovers of Spirit and Opportunity made Mars actually seem inviting, like you could pitch a tent there and hike around for days. The Jet Propulsion Lab in Pasadena hit back-to-back homeruns with these two wee warriors, which continue to send images back from the Red Planet – over 35000 and still counting. See some at marsrovers.jpl.nasa.gov.

On July 4th, JPL slammed an impactor from its spacecraft Deep Impact smack into Comet 9P/Tempel 1, a stunning feat of engineering and planning. And the whole crash was captured on digital images, apparently for insurance purposes. You can see it all at deepimpact.jpl.nasa.gov.

And of course, Planet X was found by astronomers working at Palomar. Temporarily named Xena - for the television warrior princess, I kid you not - she is bigger than Pluto and a heckuva lot farther out. Guaranteed to resurrect the “what-is-a-planet-really?” debate, it is possible that because of this discovery Pluto may be demoted from planet to “trans-neptunium object.” Mark my words, there will be insurrection in the streets if that happens!

These are just a few of the big discoveries this year. My hope is that all this can be an impetus for you to make 2006 a great year in astronomy – for yourself! Maybe this coming year can be the year you decide to actually do some of the things you’ve always wanted to do in this exciting discipline. Here are a few suggestions you might resolve to tackle this year.

• Resolve, perhaps, to get a good book on astronomy from your local bookstore or amazon.com. But get one that is at your level! No need buying an upper-level astrophysics treatise if you just want an overall picture of the cosmos.
• Resolve to either buy or borrow a new or used telescope. Finally you’ll be able to see the planets and the Moon and nebulae and star clusters for yourself, and on your own time. And then you can share your excitement with friends and family. How to buy a proper scope is found at astronomy.com.
• Resolve to buy one astronomy software program. Programs like Starry Night or Redshift can take you all over the skies in the comfort of your own home. And the graphics in the latest offerings are jaw-dropping.
• Resolve to do your own naked-eye sky observations. For example, you can make a hobby out of observing the Moon for a month and how it goes through its phases. Or you can observe where the sun rises and sets throughout the year, or how it traverses across the sky from season to season.
• Resolve to make your house more sky-friendly. Install lights this year around your home that direct light downwards, and out of your neighbor’s yard! Set them to turn off after a certain stretch of inactivity. We owe it to each other and to our children to make the night sky darker and more brilliant - for everyone.
• Resolve to stay up for one meteor shower this year. They occur all year, some are better than others. The good ones are absolutely spectacular! You can find a calendar of this year’s showers at www.imo.net.
• Resolve to get to know the constellations for the different seasons. There are fascinating stories involved in each one of these, and not just the Greek and Roman stories. Countless cultures throughout the world have their own sky stories, many of which are just great reading.
• And if you have the money, you might resolve to see this year’s total solar eclipse on March 29th. It starts in Brazil, sails across the Atlantic, through the Sahara, into Asia Minor, ending in Mongolia. No money? Join a club. You can wait with me until 2017 when one sweeps through the Northwest US.
• Resolve to visit an observatory. One of the world’s premiere scopes is on Palomar Mountain. Take a day with the family and visit those sacred grounds. There are full tours available for groups.

One way or another you can make this wonder-filled discipline of astronomy, one growing daily in knowledge and wonder, your own. No need to wait for the pros to bring you the great gifts. Go out and discover them yourself this year!]]>ritter777@gmail.comNone2006-01-15T20:30:57-08:00http://www.firstlightastro.com/skiesabove/files/70d7b281e7bd617bee7de95a0e1c0904-93.php#unique-entry-id-93http://www.firstlightastro.com/skiesabove/files/70d7b281e7bd617bee7de95a0e1c0904-93.php#unique-entry-id-93The holidays are over. It’s time to go back to school! And time for another pop quiz to test your knowledge of the cosmos! All right, no need for spitwads to the back of my head. This is just for fun, and to increase your knowledge account in the Bank of the Universe. Ready?

1. T/F Stars come in only one standard color; bright white.

Boy, you’d think so, looking at an unpolluted night sky with all the trimmings. It at least appears that all those dazzlingly sparkly things up there are white. But it’s not so.

Stars come in a wide variety of colors: red, orange, yellow, white, and blue. One question may come to mind now: Why have I, your humble purveyor of cosmic knowledge, not been institutionalized? Anyone can see clearly that there are no colored stars up there!!!

That’s actually near the truth. It appears there are no colors up there. But – sit down – most of the stars we see up there really are colored.

The fault, dear Brutus, is not in our stars, but in ourselves. Our eyes are not designed to see the blues and the red ends of the spectrum very well. The middle part of the visible spectrum, around the yellow part, we can see well, as the designers of all fast food restaurants know.

And the parts of our eyes that see color just aren’t too sensitive, either. They need a lot of energy to get them going, which is why we don’t see colors well in dark rooms.

To see the star color differences with our eyes we need to see colored stars next to each other. For example, there is a beautiful double star combo (a binary) called Albireo in Cygnus When seen through a backyard telescope one star bleeds blue, the other red.

And some stars by themselves show their true color. Aldebaran in Sagittarius shines up nice and red in the summer skies.

For truer colors one needs to use imaging equipment that is equally sensitive to all the wavelengths. That’s one reason why those images on Astronomy Picture of the Day are so colorfully stunning.

Answer: False

2. T/F The red stars are hot, and the blue stars are cold.

Most of our modern day appliances have blue colors to indicate something cold, and red to designate heat or fire. But the universe overall has its own color codes.

Stars give off energy in all wavelengths of light. But, to make a long story short, there are laws in nature that say that hot things give off a lot more of the wavelengths on the blue, high-energy end of the spectrum and not as much on the red, lower-energy end. Contrariwise cooler objects can’t spit out as much of the energetic blue wavelengths as they do the wimpier red ones. So the hotter stars actually appear bluer and the cooler stars redder.

Thus, although stars are spitting out all types of energy, what they spit out the most is what wins them their color prize.

Answer: False

3. T/F Well, then red Mars must be cooler than blue Neptune!

Planets, as opposed to stars, don’t give off their own visible light. They reflect it. And that makes all the difference in the worlds. Here’s what I mean.

Stick an iron poker in a fire for a while, and then take it out. If the fire is hot enough you’ll get the poker pretty hot, maybe even “white hot.” As it cools, it becomes yellow, then orangey, then reddish, then fades to black. The whole time that it had some color it was giving off its own light. Like stars do!

But things like planets and butterflies and hamsters named Larry and you and me don’t give off visible light. When the lights are off we are invisible.

When a light is on us, however, we reflect some of those wavelengths and absorb others. For example, a white light rains down on us all the wavelengths of light. The molecules that make up our body and clothing and everything else around are built such that they absorb some and reflect others.

If a molecule absorbs the red end of the spectrum, but reflects the blue end, it appears bluish. If it absorbs red and blues, it probably then reflects green.

It’s the same with those planets out there. They have a light source, too – our sun. Mars has compounds on its surface that reflect the redder end of the spectrum giving it that reddish-brown color.

Neptune has gases in its upper atmosphere that reflect blue light and absorb the red end of the spectrum. So Neptune appears strikingly blue.

But the colors of the planets, like the color of your clothes, have nothing to do with temperature, but with how the molecules they are made of absorb or reflect different wavelengths of light.

Answer: False.

Do better this time? Worry not if you didn’t. These are all common misunderstandings held by a lot of people, and now you are a little more knowledgeable about the universe than you were just minutes ago.

Until next time, clear skies!]]>ritter777@gmail.comNone2006-01-22T20:26:17-08:00http://www.firstlightastro.com/skiesabove/files/d47c44a184d8d7fc328eca356e2e3ee1-92.php#unique-entry-id-92http://www.firstlightastro.com/skiesabove/files/d47c44a184d8d7fc328eca356e2e3ee1-92.php#unique-entry-id-92There is a hideous monster right above our heads tonight!!! Well… maybe not a monster. More like the head of a really ugly woman. And admittedly you kinda have to use your imagination to see it. To be honest, probably the best you can make out is her eyes. Make that her eye - singular.

I guess it’s not really that frightening after all.

Well, let’s have a nice little discussion anyways on the constellation directly above our heads tonight, the array of stars referred to as Perseus.

To find it is an easy task. Go out in the early evening and face south. Look up high and find the Pleiades, that famous little cluster of stars often miscalled the Little Dipper.

Just a few degrees “above” the Pleiades – about the width of three fingers held at arm’s length – are two stars that represent the famous winged feet of Perseus.

Continue to follow that direction over your head with the line of stars that curves slightly to the right. Those stars are Perseus’ leg and torso. The bright star of the group, half a handspan up, is called Mirfak. This name comes from the Arabic “Marfik al Thurayya,” loosely translated as “Elbow Nearest the Many Little Ones.” The elbow belongs to Perseus, those “little ones” are the Pleaides.

Keep going a little further up, without wrenching your neck, to see the stars of Perseus’ head. You’ll know you’ve gone too far in one of two ways: either you will come upon the famed W of Cassiopeia or you will have fallen over backwards and bonked your head on the ground.

Many are familiar with the story of Perseus, which is a long sweeping epic to say the least. But the bottom line as far as we are concerned is that Perseus was the son of a looker named Danae. Danae was a beauty, and the god Zeus was a womanizer, which is how Danae came to bear a jovian child and name him Perseus.

Through a series of stories and adventures Perseus acquires a special sword, a shiny new shield, and some winged sneakers that would make Michael Jordan envious.

He eventually visits the Sisters Gorgon, three not-too-attractive siblings who shared one eye and one tooth between them. Really. And there he slays the one named Medusa, by lopping off her snakes-for-hair head.

He goes through some more escapades, not least of which are rescuing and marrying Andromeda, and accidentally killing his grandfather.

For all his heroism he is granted a place in the sky just overhead tonight. But I neglected to mention that he is holding in his hand his putrescent prize. Just to the right of the curved line of stars is the horrifying head of Medusa!!!

The bright star just to the “right” of the line, halfway up, is the hideous eye of the beast. This star is called Algol, from the Arabic “Al Ghul,” which means Mischief Maker.

Now this star has a pretty fascinating little tale to tell itself. It is a binary (two-star) system just 95 light years from us. The two extremely close stars revolve around each other every 69 hours.

We can’t actually see two stars there but we know they are there and going round each other because the dimmer one actually eclipses the brighter one, causing Algol to dim every 2 days 20 hours and 49 minutes. It is an eclipsing binary. It fades by a factor of about three for about 10 hours (as the dim star passes in front of the brighter) and then brightens back to original magnitude.

Why, it’s almost as if Medusa is winking at us! Ooooh… scary!

Although they have no single hero story as was handed down to us in the West, the Chinese have some great stories about this part of the sky.

The arc of stars that is Perseus’ torso is called T’ien-tchouen and Tsi-choui, which represented a boat and rising waters respectively. These were reminders of the imminent flood season.

Ta-ling were the series of stars circling around Algol. This was the great trench where many prisoners killed in mass executions in August were buried together. Tsi-chi, our Algol, is the great heap of corpses waiting for the trench. Mmhmm…

But wait! It gets even more gruesome.

Astronomers in ancient times were more astrologers than anything else. They needed to know the stars and other heavenly bodies to forewarn the king when bad times might be round the corner, or announce the perfect time for make war, or when to make the next hair appointment.

Well, apparently there were these two Chinese court astrologers, Hsi and Ho, who were too busy enjoying the “good life” of court astrologers to notice an upcoming solar eclipse. Bad move.

Usually the Chinese people were warned of such an event and got out their pots and pans and beat the heck out of them, scaring away the dragon who was eating the sun so that the great beast would burp it back up.

No warning this time and the dragon nearly got away with eating the sun and running away with it. The Emperor had their heads for that faux pas, and the melons of Messrs. Hsi and Ho were put in the sky as reminders to future astrologers not to mess up!!!

Their heads can easily be seen with binoculars as the famous and beautiful double star cluster in Perseus, near the top of the arc of stars.

I use the story of Hsi and Ho in my class as object lessons for the consequences of not doing your homework. Alas, it doesn’t work.

Until next time, clear skies!]]>ritter777@gmail.comNone2006-02-19T20:22:31-08:00http://www.firstlightastro.com/skiesabove/files/bce495675a423fbc9f3020a201eb71e8-91.php#unique-entry-id-91http://www.firstlightastro.com/skiesabove/files/bce495675a423fbc9f3020a201eb71e8-91.php#unique-entry-id-91Rocks plus water equals life.

One might derive this equation by reading recent features on Mars or Jupiter’s moon Europa, or articles covering any of the dozens and dozens of planets discovered outside our solar system in the last decade. Find some “rocky” body, make sure there is water, and life is bound to be abundant.

We humans have this deep desire and fascination in finding life outside of earth. I mean, look how big the universe is! Life has to be thriving out there!!! And, c’mon, it is fun to imagine what it might be like. Witness the success of all those science fiction books and movies.

Well, at the risk of throwing a clinical wet blanket on the “Life Is Everywhere, We Just Haven’t Found It Yet” bandwagon, allow me to take a sober, sadly brief, and admittedly incomplete look at some more items to look for in a search for life, other than dirt and water, that is.

For example, life needs an energy source, but just the right source. A great big star throws out so much intense, nasty radiation that unless extremely well-protected, any imaginable organic life would perish. No ozone layer can shield from the death rays of the big guys.

And the big stars die very quickly – our sun would have died long ago if much bigger. Moreover, when the big ones do go, they go out with a bang and virtually sterilize any possible living quarters within light years of their death scene.

Smaller stars could provide necessary energy, but a life-support planet would have to get lethally close to the star to receive enough energy to fuel life.
Most all the extrasolar planets that have been discovered are Jupiter-like planets. That’s good… and terrible.

Good, not because the big ones can harbor life, but because little life-support planets need a big brother jovian-type planet out there to protect them from the onslaught of incoming comets and other debris. But it is a terrible thing because these big gassy guys have a really disturbing personality quirk.

Formed at great distances from their parent star, most gradually move towards the parent star. This disrupts, fatally, the orbit of any little earth-like critters in the way trying to get on with life.

For some reason our big planets stopped out there and continue today to protect us from afar.

And even if an earth-like planet were found out there somewhere some day, it has to be the right distance from its star, the right mass with the right gravity and right atmosphere covering the right multi-layered body, with the right neighbors, and with a proper moon to insure a stable rotation - all of which permit liquid water not only to exist, but to remain on a planet.

Life also needs the right place in a properly aged galaxy, the right type of galaxy, a perfectly aged and lonely star in that perfect galaxy, etc., etc. One could list literally dozens of other necessary parameters for a planet to be suitable for life – any imaginable life - but I am limited here by space and time (pun intended).

But allow me to bring in this controversial philosophical consideration: What if we found somewhere in our galaxy a perfectly pristine planet, absolutely suitable for any imaginable complex organic life? Does it follow that life automatically springs forth from this non-living orb?

Theistic scientists would say that a Supreme Being could introduce life onto a planet well suited for it. Their enjoyment comes in trying to figure out how and when He did it – those pesky and elusive details of the great mystery.

Nontheistic scientists have a more formidable order to fill – how life could spring from nonlife with no intervention. This is truly one of the Great Unsolved Problems of Science.

So far countless scientists in the last century have been unable to create even the simplest life in the lab, places which themselves represent the most pristine possible conditions for life to arise, were it able to arise by itself.

It doesn’t follow that it is impossible for life to start on its own, but the Hill of Improbabilty has thrust upward into a daunting and menacing Mountain.

Might there be life out there? I don’t know. But I do know rocks and water do not mean life.

Bottom line: Before you read an article proclaiming how the universe just has to be drowning in life, first put on your Skeptic’s Hat. Science literature is not an archive of infallible truth, this column included. And feel free to ask the tough questions. Reasoning together we can discover great truths.

That’s the beauty of science.]]>ritter777@gmail.comNone2006-03-05T20:19:00-08:00http://www.firstlightastro.com/skiesabove/files/1ac2001da9551a70bd0bce9cd31cbe97-90.php#unique-entry-id-90http://www.firstlightastro.com/skiesabove/files/1ac2001da9551a70bd0bce9cd31cbe97-90.php#unique-entry-id-90So you want to know what that bright light is hovering mysteriously in the eastern predawn skies, the light you could swear wasn’t there just months ago.

I thought you’d never ask!

For early risers, those who must send kids off to school or get early onto those maniacal freeways of ours, there has been a shimmering orb that rises before the sun and has been entertaining us since the beginning of January.

Why, it appears to be a star! A wandering star, to wax poetic about it, the way it changes position through the weeks. And it was once believed to be just that – a star that roamed, not one fixed onto the heavens above like all those other pricks of light that trustily return to their same positions night after night, month after month, year after year.

The Greeks gave this heavenly body and a half dozen more the name “wanderer” - in Greek “planetes” - which we formed into “planet.”

Of course, the big bright one now gracing our skies, the brightest of them all, is Venus, our nearest but not so dearest neighbor.

At the moment she is a mere 49 million miles away from us, a stone’s throw in cosmological terms. And right now, unknown to many, there is a spacecraft headed her way.

The European Space Agency is sending the Venus Express there to study that bizarre, twisted sister of ours. Scheduled to enter Venusian orbit just a month from now, it will study the hellish surface of the planet and its bizarre climate.

What is so outlandish about that pretty addition to our morning commute? Hmmm… let’s see. Try everything.

Yes, she is the same size and mass and density as our planet, but that’s it as far as being our twin. This dysfunctional sibling of ours has all the earmarks of being designed for the devil himself.

The surface temperature is about 900 degrees Fahrenheit. Check your stove now and see that it can’t get above about 500 Fahrenheit at full blast. It’s just a little toasty on the Bright One.

And if you could land on its surface you’d be subject to pressures that are nearly 90 times that of our own atmospheric pressure. That’s like being a kilometer under water. I don’t know about you but I get all whiney with the crushing pressure that comes in diving into the deep end of a backyard pool, let alone more than a half mile down into an ocean. And we’re talking only of Venus’ atmosphere, its “air”!

The Soviet spacecraft sent there in the 1980’s could survive only an hour on the surface before Venus claimed it as its latest victim.

The choking, cloud covered atmosphere of Venus is so unbelievably thick that only the biggest rocks can plummet from space through to the surface. That’s why we see no craters there smaller than about two kilometers. Those poor wannabe impactors were burned up in the beefy atmosphere, or broke apart into a million pieces before reaching the face of Venus.

And even if you manage to make it through the thick sulfuric acid clouds, through the sea of baking carbon dioxide gas, and hit the surface – even if you manage to make an impact and leave your mark on that bleeding hot facade, odds are your grave won’t be marked for long.

It appears that the surface of Venus, unable to release its internal pressures from below slowly and regularly like our planet does, lets it all off at once. This amounts to what astronomers believe is a massive global volcanic phenomenon that completely resurfaces the face of the planet, obliterating all signs of previous impacts. Yeah, there’s a fun place.

Ideally the Venus Express will help us understand that beautiful diamond in the sky a lot better. What happened to all her water? What happened there early on to give Venus such a vastly different outcome? When and why did things so horribly bad?

Whatever we learn by delving deeper into Venus one thing is for sure, it will make me appreciate our beautiful Blue Wonder even more.]]>ritter777@gmail.comNone2006-03-19T20:15:00-08:00http://www.firstlightastro.com/skiesabove/files/5f15517a0763eaadd4db2dde9a3c6ed0-89.php#unique-entry-id-89http://www.firstlightastro.com/skiesabove/files/5f15517a0763eaadd4db2dde9a3c6ed0-89.php#unique-entry-id-89For being a nice little ice rock 2900 million miles away, wee Pluto sure has been making the news lately. Why, it's almost as if it senses it may be losing its status as a planet and is making every attempt to make us believe that it is no different from its neighbors - maybe just smaller.

Discovered by Clyde Tombaugh less than hundred years ago, Pluto has always been an enigma of sorts. Before its discovery there were all these monstrous planets in the outer system; Jupiter and Saturn had been known since time immemorial, then with the coming of telescopes Uranus and Neptune were discovered in the 18th and 19th centuries.

They were huge and gassy and floating around the sun nicely with the rest of us.

Then along comes tiny Pluto. It was no bigger than our country, made mostly of water ice, and had an orbit so tipped over and egg-shaped - not the nearly circular orbit of its neighbors - that you'd think it had been adopted into our system rather than born with the rest of the brood.

But it was categorized as a planet anyway and got its own special name.

But now things have changed. There's a new set of animals in the zoo and Pluto may actually be one of them instead.

It was proposed over in the mid-1900's that there might be a belt of leftover stuff from the creation of the solar system, wannabe planet material, in a vast donutlike cloud of icy debris extending from Neptune out another several billion miles, in an area often called the Edgeworth-Kuiper Belt.

But it wasn't until 1992 that technology caught up with theory and we could actually see one of the debris bits. And then another was found, then another, then another. Now we have seen over 800 of these Kuiper Belt Objects. Now we have a dilemma.

Some of these KPO's are actually bigger than Pluto!!! Are they, too, planets? Or was Pluto perhaps just the first Kuiper Belt Object discovered?

Perhaps fearing it may lose its planet status, Pluto isn't going down without a fight. In just the last year, it has recently revealed previously unknown secrets of itself.

Pluto has a moon, Charon, discovered in 1978, over half the size of Pluto. The two are essentially a double planet. But just last year two more icy little guys, measuring just over 30 miles across, have been seen orbiting Pluto. Pluto has a least 3 moons!

Some believe that these moons, including Charon, were formed when Pluto got clocked real badly some time ago by an impacting object. This collision sheared off what became Charon and the two new moons.

This hypothesized collision may also have put enough fine debris into the vicinity for Pluto to actually have formed a wimpy ring system of its very own!

Multiple moons? A ring system? You can almost hear little Pluto crying out, "I am a real planet! I am a real planet!"

Whether or not the International Astronomical Union changes the status of Pluto in the coming months, maybe it's a win-win situation for the Little One.

If it remains an official "planet" it will still be part of the Elite Nine. Yippee for all traditionalists!

But if it turns out that Pluto is reclassified as a Kuiper Belt Object, that's OK, too. It was the first one discovered, it's the nearest one to the inner solar system, and the first one to have a spacecraft sent to it. It is would be then the premiere Kuiper Belt Object in a field of millions.

Until next time, clear skies!]]>ritter777@gmail.comNone2006-04-01T20:10:37-08:00http://www.firstlightastro.com/skiesabove/files/46d0733157268719fdf4e1a8cbef8356-88.php#unique-entry-id-88http://www.firstlightastro.com/skiesabove/files/46d0733157268719fdf4e1a8cbef8356-88.php#unique-entry-id-88What if I said that astronomers now have a pretty good idea about how the universe has shaped up over the last 13.7 billion years, since the first trillionth of a trillionth of a trillionth of a second until now? Sounds rather pompous, doesn't it?

But discoveries in the last decade and especially the last couple months have raised sky high our confidence level in our understanding of how this universe has changed over time. Here are some highlights...

In the early 1900's both Edwin Hubble and Albert Einstein independently had their own pioneering insights that led us to believe our universe is expanding. Astronomers have been forced to conclude since then that this universe - all matter, space, energy, and even time - had a beginning many long years ago.

You can imagine why they'd think that. If we ran the film of our expanding universe backwards that there must have been a point, how ever many years ago, when it all started. This moment was sarcastically labeled "big bang" from the skeptical astronomer Fred Hoyle back in the '50's.

Moreover if the universe is cooling off now, then it must have been hot - real hot - back then. So, it was hypothesized, it must have been a "hot big bang."

On top of all this some astronomers had to try to explain some mystifying characteristics of the cosmos by invoking a sudden expansion of the universe when it was a mere fraction of a fraction of a second old, an expansion several times the speed of light, lasting less than the twinkling of an eye, in a period understatedly called "inflation." That would now make it an "inflationary hot big bang."

So how does one go about proving this?

Well, it was thought that if it was a hot big bang, then there should be some heat left over from the earliest times of the creation, sort of like heat left over in a kitchen long after the oven has been turned off. This was hypothesized many years ago and the leftover heat was called the cosmic background radiation. And it was first vaguely detected back in the 1960's.

But in the early 1990's, when technology finally caught up with theory, a satellite called COBE, with very sensitive equipment, was able to see this background radiation all around us at exactly the cooled down temperature it was predicted to be - the "afterglow" of a hot big bang. And there was much rejoicing.

Then it was time to send up a new, much more sensitive satellite that could see the background radiation in much greater detail. Could it see traces of the proposed great inflation, too?

The Wilkinson Microwave Anisotropy Probe - WMAP as its also known, thank goodness - gave us in 2003 an amazing view of the universe that showed the details COBE could not.

And all this seemingly dull cosmic background radiation picked up from WMAP was actually a treasure trove of complicated information that answered some of the great hidden mysteries of the cosmos. Among other things astronomers could now determine were the age of the universe (13.74 billion years), and its composition (4% atoms, 22% dark matter, 74% dark energy).

It was a watershed moment for cosmology. And there was much rejoicing.

Yet with all this new info, there still was not enough data to see remnants of the proposed inflation period.

Now the newest WMAP data is being published and they show not only more details about age and composition and geometry and expansion, but they reveal the first evidences of that elusive inflationary period, that hyperexpansion during the first trillionths of a second after the Creation Event.

It's looking more and more like we have ourselves an inflationary hot big bang after all! And, again, there is much rejoicing.

Yes, it sounds arrogant to say that we think we know pretty well how the universe came into existence. But that came with decades of hard work, and there are still plenty of details to be worked out, to be sure.

I have oversimplified it here, and we'll go into deeper aspects in future columns, but what cosmologists are showing us today is a universe that is nothing less than a grand work of stupendously complex art, a hyperfine-tuned magnum opus, from the earliest moments of creation to now.

Even more sensitive satellites are being sent up soon. Stay tuned. It just keeps getting better.]]>ritter777@gmail.comNone2006-04-16T20:04:27-07:00http://www.firstlightastro.com/skiesabove/files/172bdb11e3d07ac772c8e47d2875b758-86.php#unique-entry-id-86http://www.firstlightastro.com/skiesabove/files/172bdb11e3d07ac772c8e47d2875b758-86.php#unique-entry-id-86Go out tonight and look up. You will see some great constellations, to be sure. There's Leo the Lion above. To the north, not so well hidden inside Ursa Major, is the asterism of the Big Dipper. To the west there are the twins of Gemini.

Those constellations all have their multicultural stories and myths, especially from western peoples, principally the Greeks and Romans. And the peoples of the east have plenty of skylore, as well.

But there is a constellation up above, one stuck between two others of great repute, with absolutely no long, drawn-out myth to tell around the fire with the family.

And you'd be hard-pressed to find it if it weren't for some notable big brothers surrounding it. But let's try.

Go out in the 8 o'clock hour tonight, face south, and look directly - I mean directly - above your head. Astronomers call that point above your head "zenith." Just lower you will see the backwards question mark of Leo the Lion. Keep looking over your head without falling backwards and you will see the Dipper.

Between those two, at zenith, is a small, barely visible collection of stars called Leo Minor, the little lion. Never heard of it? Neither have most people.

It was created by a 17th-century astronomer named Johannes Hevelius. There happened to be a little room between Leo and Ursa Major, a small grouping of just over a dozen stars, so he simply wedged a tiny lion in there.

Who was this Johannes Hevelius? And how dare he?

Born in 1611 in what is now Poland, in the city of Gdansk, which was later called Danzig, which was later renamed Gdansk (whew!), Jan Heweliusz had a name change of his own. He latinized it to Hevelius, which apparently was a cool thing for educated people to do back then.

Hevelius was well off, financially speaking, due to his family's brewery business. With his wealth he built one fine observatory in Gdansk, a place he liked to call Stellaeburgum, loosely translated, StarTown.

The superb, hand-crafted instruments that littered the site were built mostly by Hevelius himself, a master craftsman. His observatory stretched across the upper floors of four houses, and included an air telescope with a focal length of 130 feet! Try setting that up at your next star party!

With this great arsenal of instruments Hevelius did considerable and important work on tracking sunspots and the planet Mercury, and mapping the lunar surface. He wrote books on the heavens and the history of astronomy.

Hevelius discovered comets, as well, and with his fancy equipment accurately plotted the position of over 1500 stars. No coach potato, that Mr. Heweliusz!
And to fill some of the empty parts of his sky, the renowned astronomer gave us new constellations, to wit, Hunting Dogs (Canes Venatici), Lizard (Lacerta), Lynx, Sextant (Sextans), and Fox (Vulpecula).

Oh yeah! And that little constellation directly above your head tonight, Leo Minor, the Little Lion.

Posted by Mark Ritter at 2006.04.16 11:42 AM | Comments (0)]]>ritter777@gmail.comNone2006-05-01T20:01:02-07:00http://www.firstlightastro.com/skiesabove/files/f7ac8803d294e2bc966008cbfd39ed24-85.php#unique-entry-id-85http://www.firstlightastro.com/skiesabove/files/f7ac8803d294e2bc966008cbfd39ed24-85.php#unique-entry-id-85There are coincidences, and then there are amazing coincidences. If you've been reading this column for a while you know already that there are some pretty "fortunate circumstances" that have occurred over the last billions of years, circumstances without which you would not be alive to read this.

Our just-right distance from the sun, the preternatural creation of our Moon, at least two incredibly well-timed nearby supernovae before our sun was born, our extremely well-placed planetary neighbors, etc., etc. - the list is endless.

But when several sets of separate, seemingly unrelated events occur over a period of billions of years - a number of simultaneous and diverse phenomena which must work and change in flawless unison or it's curtains for life - then it's time now to drop the jaw in utter awe.

When life was first introduced here, nearly four billion years ago, the sun wasn't the bright and shiny star it is today. It was probably about 30% less luminous than now, meaning it poured out 30% less energy.

If we know that a drop in energy of only about a percent or two from what we have now would turn us into a giant snowball, then how could life survive back then at a time the sun was so much dimmer?

Well, back then, so the records show, there was a lot more carbon dioxide in the air. Carbon dioxide is a greenhouse gas, efficiently trapping energy like a huge blanket around our planet.

So although the sun poured out a lot less energy eons ago, the greenhouse effect was in full kick back then, offsetting the wimpy sun, and keeping the planet nice and warm.

The big questions now? Where did all the carbon dioxide go as the sun got brighter and brighter? Why didn't life on this planet bake away a long, long time ago under our heavy blanket? Put on the proverbial thinking cap and take a seat.

Carbon dioxide can be cleaned from the sky in several ways, but it can't happen too fast, nor too slowly - it has to happen at just the perfect rate to match the brightening sun. One way involves water.

Early oceans were important imbibers of CO2 from the air. Carbonated beverages are perfect examples of water filled with dissolved carbon dioxide. But even the oceans have a limit. Could land help out here perhaps?

Yes, land can absorb CO2, as well. There is a class of a very abundant rock called silicates that can undergo a chemical reaction with carbon dioxide. (Fear not! I won't give the equation!) When silicates become exposed to the air during erosion, they get together with CO2 to form carbonates and sand. Yes, sand.

But erosion rates and plate tectonics and the uplift of mountains to expose new rock, etc., all have to be perfect so that the decrease in CO2 matches the increased energy output of the sun.

Surprise! It was! And still is.

A long time ago, when there was much more intense lifting of the land and exposure of new silicates, more CO2 could be sucked up at just the right rate. But the plates and uplift have slowed considerably in the billions of years that have gone by. Why aren't we baking right now in all the carbon dioxide that couldn't be absorbed?

Amazingly, plant life showed up at just the right time to work as a team with the land. Remember from school that CO2 is something plants require. Well, early plants didn't require much CO2, later plants required more. These requirements helped offset the fact that the silicates were playing a smaller and smaller role in the removal of CO2.

And then shell critters showed up at just the right time to continue helping! These tiny beasts turn CO2 into special carbonates, the building blocks for their shells.

And when the plants and shell critters went and got themselves dead and buried they effectively took the CO2 with them.

So as the sun got brighter and brighter, and bathed us in more and more energy, our warm blanket got thinner and thinner.

It is even more amazing than I can describe in this short space. It is such an astonishing set of events it has its own name - the Faint Sun Paradox. But the Big Picture here, that several entirely disparate events took place at just the right time to maintain perfect temperatures for billions of years goes beyond cute coincidences and enters into the realm of the miraculous.

What a world!]]>ritter777@gmail.comNone2006-05-14T19:06:58-07:00http://www.firstlightastro.com/skiesabove/files/f94f185ea62ce11511394aa2e29c41e9-84.php#unique-entry-id-84http://www.firstlightastro.com/skiesabove/files/f94f185ea62ce11511394aa2e29c41e9-84.php#unique-entry-id-84There are several common misunderstandings about our little satellite above, also know as The Moon. I hear them all the time. Let's look at some, and try and clean up its image a bit.

1. One myth is that the Moon doesn't spin around like earth does. All we see is one side of the moon, ever. If the Moon really does spin about, so the thinking goes, we should see the other side of it, right?

Well, it's precisely that it does spin around that allows us to see just one side. Imagine being up a couple stories looking down on two children, one walking a big circle around the other.

In order for the circling child to continue to face the stationary child, that little one must continually turn while walking. If she didn't "spin" slowly while orbiting around, she would appear to be staring at some distant object the entire time. The child in the center would only then see all around the orbiting child's head.

Like the child, the Moon spins around one time for every orbit.

2. The Moon is bigger when it is full and near the horizon.

Sorry, this is a myth, as well. A rising Full Moon is the same size as it is hours later when it is high in the sky. Some believe that this optical illusion flies so well because at the horizon we compare the Moon with points of reference - distance buildings or trees or lights - which make the Moon appear bigger.

We even expect this illusion in artwork. If the Moon is drawn to real scale in the sky of a painting, rather than as a big bright ball, we are not amused; it just looks like it's too small.

Next time there is a full moon, go out when it is on the horizon, when it appears so big, and you'll see that you can cover it with a finger held at arm's length. Wait for a couple hours when it is higher in the sky and try it again. You can cover it then exactly as you covered it when it appeared so big earlier.

3. There is what we can see of the Moon, and then there is the "dark side of the moon."

Not really. There is always a dark side of the Moon, but sometimes it faces us. This is New Moon, when the Moon is between the sun and us. And when we see the so-called "half moon," more accurately called quarter moon, we see some of the lit side and some of the dark side. More accurately that part of the moon we cannot see should be called the "far side" of the moon, not the "dark side."

4. The sun is up during the daytime, the moon is up during the night.

Of course we can define daytime as when the sun is above horizon. But we do not define the night as when the Moon is up. "Nighttime" is when the sun is below horizon. The Moon is part of the definition of neither daytime nor nighttime.

As a matter of fact, during many "daytimes" you can see the Moon - if you know where to look. During this coming week you can see the Moon in the early morning in the western skies. You can then follow it day after day as it moves over towards the sun.

5. We never went to the Moon.

There are some people, few but vocal, who believe all the Apollo missions to the Moon in the late 60's and 70's were a giant hoax perpetrated by our government. I wouldn't even mention this except for the fact that there are a good number of good people out there who are actually sitting on the fence with this one.

The best way I can address this in such a small space is to point you to a website called "Bad Astronomy." Specifically one of the pages there rebuts the Fox TV show "Conspiracy Theory: Did We Land on the Moon?" It is here. Go and read and be enlightened.

Actually the next myth is easier to believe than the last...

6. The Moon is made of green cheese.

This one may actually be true. No, I jest! As far as I can tell, using the Oxford English Dictionary as a source, this phrase goes way back, hundreds of years. It was probably used with at least a pinch of sarcasm. Judge for yourself:

John Cotgrave in 1611 gives us, "(Wee say of such an Idiot) hee thinkes the Moone is made of greene cheese." Sir Charles Wilkins in 1638 wrote, "You may as soon perswade some Country Peasants, that the Moon is made of Green-Cheese (as we say) as that 'tis bigger than his Cart-Wheel." (Green in both cases means "new" or "fresh.")

It's like someone today saying, "Soon you'll have him believing the Apollo missions were faked!"

Until next time, clear skies!]]>ritter777@gmail.comNone2006-05-28T19:01:12-07:00http://www.firstlightastro.com/skiesabove/files/c88902c68139c2a7ea0973b445344d9b-82.php#unique-entry-id-82http://www.firstlightastro.com/skiesabove/files/c88902c68139c2a7ea0973b445344d9b-82.php#unique-entry-id-82One of the awe-inspiring things we wannabe astronomers look at through our telescopes is the Moon. When our satellite is around its first quarter phase, the time when the sun's light strikes it at an oblique angle, its craters seem so real and well-defined that you'd believe they could reach through your scope and poke you in the eye.

Of course those brighter, crater-filled areas have obviously taken a beating. They are the "highlands" of the Moon. But what about those darker areas we see? What about the "maria"?

Turns out they got hit even harder. Through a telescope they appear relatively smooth and featureless, but it is precisely those characteristics that lead us to believe that those parts of the Moon suffered severely.

And that we must have suffered, too.

Those dark maria are the lava-filled basins from monstrous impacts that occurred about 3.9 billion years ago. These were no cute little rocks that struck our little buddy. They were enormous asteroid types that pummeled the Moon, all in the same blink of geologic time.

And when we look at battered Mercury we notice that there, too, and at the same time, it rained down destruction.

The plot thickens when we see that Mars' whole southern hemisphere shows the same widescale blasting, and it dates – surprise, surprise - from that same time of terror now called the Late Heavy Bombardment (LHB).

What is tarnation is going on? Why all this ruination, and during such a short spurt of time? And why don't we have the scarred face that the rest of our neighbors do?

Well, the latest story goes like this, and its outcome is another one of those "great coincidences" we are becoming more accustomed to in astronomy.

Early on in the history of the solar system this was one dirty place, filled with space debris from nearby supernovae that littered the spacescape with the whole periodic table.

Much of the stuff collected into a new star, our sun, and a lot of floaties, rocky and icy flotsam, eventually became planets and asteroids and comets.

This congestion meant a lot of crashing and slamming and kabooming, like driving down the 15. But this demolition derby all died down considerably just over 4 billion years ago. The solar system was relatively calm and clean by then.

Then why the sudden and frightful pulse of projectiles that wrecked havoc in the inner solar system? What exactly happened in this Late Heavy Bombardment?

Well, to give an honest scientific assessment, nobody knows what exactly happened. But we do have a good idea based on a truckload of evidence and some fine computer work. And it involves Jupiter and Saturn.

As these two great giants were forming their orbits were not fixed, but were influenced by each other, and by the asteroid belt, other planets, and a gigantic dumpsite in the outer solar system called the Kuiper Belt.

Through a complex Newtonian dance Jupiter gradually moved in, Saturn slowly moved out until they reached what we call in astrospeak a "resonance."

Briefly, they apparently agreed on orbital distances which allowed Jupiter to go around the sun approximately two times for every one time Saturn did. In the process Jupiter nudged closer to the asteroid belt, Saturn closer to the outer Kuiper Belt and this perturbed the tiny rocky bodies there.

Many asteroids and comets got gravitationally knocked out of their orbits and plunged down, down, down toward the sun. Well, this was not good news for Mars, Earth, the Moon, Venus, and Mercury. They were all in the way.

And they got hit to a fare-thee-well. It is estimated that this brief bombardment doused our planet alone with more than 20,000 impact craters as big as San Diego, about 40 impact basins bigger than Texas, and several impact basins larger than Australia! Fair dinkum!

Of course we can't see these craters anymore because plate tectonics have covered their traces.

Good news: This whole shower gave us an extra supply of innards and heat to run the plate tectonics of our planet even more efficiently.

Amazing news: Life appeared not billions of years later, but in the same geologic breath that the LHB dissipated and the Earth cooled, at about 3.8 billion years ago.

More amazing news: If it weren't for this precisely timed dance of the outer planets, and their distances from the junkyards, and the density of those debris fields, the LHB could have happened later and completely sterilized our life-filled planet.

Next time you see the Moon in all its glory, spot the great dark basins, basins formed by those colossal collisions, and be thankful those days came -- and went. ]]>ritter777@gmail.comNone2006-06-10T18:56:44-07:00http://www.firstlightastro.com/skiesabove/files/2a2e75c2cb9fb17465fac6eeb936761b-81.php#unique-entry-id-81http://www.firstlightastro.com/skiesabove/files/2a2e75c2cb9fb17465fac6eeb936761b-81.php#unique-entry-id-81Seeing how it's the end of the school year again, it's seems the right time for another astro quiz, one with maybe just a bit if chemistry and geology thrown in for good measure. Don't worry, I know summer is on your mind, so this quiz will be just two true-or-false statements. Ready?

1. Uranus and Neptune have atmospheres rich in methane. One well-placed match would set them on fire!!!

Methane is a tiny molecule, the simplest of the hydrocarbons, CH4. Just one carbon surrounded nicely by four well-placed hydrogens, it is a powerful little energy storage unit.

Methane is in our atmosphere in very small amounts, measured in just parts per billion. Its sources are not exactly something to talk about over dinner. Rotting vegetation gives it off. Termites do. The world's millions of cattle and sheep… ahem… release tons and tons of the gas into the atmosphere every year. And - cover the children's ears - you and I donate our fair share, as well.

Methane is one of our planet's greenhouse gases, helping to keep our atmosphere nice and comfy. But it can burn, too. It is the gas that heats our ovens and stoves. One little match fires up that gas and *poof* we have ourselves a flame.

Uranus and Neptune both have a load of methane in their atmosphere. It is the reason both planets are bluish-green, believe it or not. Methane absorbs the red end of the sun's spectrum of light and reflects away the blue.

So why haven't both planets just lit up like fireballs? Because there is one ingredient missing: oxygen. Fuel needs oxygen to burn. The fuel alone, even with an available spark, would just sit there.

Thankfully for those Uranians and Neptunians there is no oxygen up there to fire up their giant planets.

2. The biggest known volcano in the solar system is on a little planet we call Mars.

How can that possibly be true? We have gigantic, nasty mountains of exploding rock right here: Etna, Vesuvius, Pinatubo. Our largest is the Big Island of Hawaii, over 30,000 feet high from head to toe. Mars? Mars is just a puny little rock half our size.

Well... Earth's inner make-up and its overall size don't really allow us to have supergigantic mountains and volcanoes. Our bigger size means a greater gravity, which keeps our mountains from poking too high into the sky. They just get pulled back down and spread out like cold Silly Putty.

And potential contenders for Solar System's Biggest Mountain, like the Big Island, don't have enough time to build up much higher. The plate the islands are riding on is moving over a hot spot in the middle of the Pacific Ocean.

A hot spot below a plate can cause a leak in that plate. By the time an island builds up substantially from magma oozing up through the leak, the plate it's riding on has already passed beyond the hot spot and a new island down the line is forming from a new leak.

Moreover, the island gets weathered eventually all the way down to the sea, which is why island chains like Hawaii can only stretch out so far before their islands go submarine. Mars, in comparison, has no oceans and essentially no atmosphere to tear down any great mountains.

Olympus Mons on Mars was a big leaky hole in the crust that just kept spewing magma from one stationary place. No plate tectonics moved it away from its hot spot.

And Mars' gravity is weak enough that the volcano could build higher and higher and higher. It stands now at about 89,000 feet and covers an area the size of our neighbor, Arizona.

That is one colossal mountain and winner of Biggest in the Solar system.

How did you do? Did you at least learn something new? Good, because that is what's really important here.

Until next time, clear skies!]]>ritter777@gmail.comNone2006-06-25T18:52:51-07:00http://www.firstlightastro.com/skiesabove/files/bd815bd86abfb0f6775d2f7a535b8317-80.php#unique-entry-id-80http://www.firstlightastro.com/skiesabove/files/bd815bd86abfb0f6775d2f7a535b8317-80.php#unique-entry-id-80Where we have been, where we are, where we are going. These are three of the big mysteries that nearly everyone who calls himself a human being wants to know. There is nary another species out there beside our own which tries to uncover meaning to life by investigating its past, present, and future, trying to make sense of it all.

And there are few disciplines in the sciences that can reveal to us as much as astronomy can - not that I'm biased at all. But a meaningful science should tell us more than just facts, more than just pure trivia; it should help us fill in a gap or two in that trillion piece jigsaw puzzle we call The Big Picture. And astronomy helps enormously.

This week we will look at where we have been. In my next two columns we will take a look at where we are and then where all this is headed. And, hopefully, along the way, we can discover something about ourselves, and our place in The Whole Shebang.

A century ago the scientific community was convinced that the universe was infinitely big and ageless. There was no beginning; it just always was. And the three dimensions of space and the one of time was it, the entire package.

Now, after a lot of hard work by a lot of clever men and women, we are firmly convinced that the universe - all matter and energy and space and even time - came into existence from nothing about 13.74 billion years ago in a burst of creation called the big bang.

To be sure things have changed over time - much energy became matter, matter formed stars, stars gave shape to galaxies, star remnants became planets, and space has stretched to unimaginable lengths - but the fact remains: there was a beginning.

Not everyone was all too excited at this conclusion. For many - including the renowned astronomer Fred Hoyle who derisively coined the phrase "big bang" - a beginning to everything, an actual event originating from beyond, was thoroughly repulsive.

But it gets more complex than that.

That our universe is expanding into unseen dimensions implies heavily that there is more to existence than the three dimensions of space we enjoy. There is something that transcends our life.

Let me illustrate by using the standard example we use in astronomy classes today, the blowing up of a balloon. Unimaginably tiny beings living on the surface of a balloon are only aware of that stretching two-dimensional surface. But they are unaware of what is outside and above the expanding balloon, or what's inside of it. It is not part of their "space." They can point neither to where it's all headed, nor to where it all started.

It's similar with us. We are on a stretching fabric of space, only ours is three-dimensional. But we cannot see any "place" we are headed for, not can we point to where we have been. Those are, in the fullest sense of the term, beyond us.

To take this even more "out there," string theory - the theory which tries to explain essentially everything - postulates that there are nearly a dozen dimensions of space, many more beyond the three we know and love.

Stephen Hawking made it still more nerve-racking for some when he told us that even time itself had its beginning at the beginning. Some transcendent cause and effect system got us here.

That we had a beginning, that all was created at the beginning, that there is more beyond space and time than we can possibly imagine has profound philosophical and theological implications. Who and/or what is beyond? What caused this universe to be? Was it an inexplicable accident or was it purposed?

Get together this week with some friends, open up your mind, don your philosopher's hat, and have at it.

Next time we'll look at some things astronomy has to offer concerning our present, and what that may say about our existence.]]>ritter777@gmail.comNone2006-07-02T18:49:46-07:00http://www.firstlightastro.com/skiesabove/files/f2efb6a650b1a442e72b4f7b24dbb9e1-79.php#unique-entry-id-79http://www.firstlightastro.com/skiesabove/files/f2efb6a650b1a442e72b4f7b24dbb9e1-79.php#unique-entry-id-79The stresses and complexities of our everyday life can cause us to miss how astonishingly unique a planet we live on. We can easily look all around us, yet see nothing.

Can the air we breathe, the ground we walk on, and the skies above our planet tell us something about our lives? Or are they just silent, background props in our restless play?

Last week we took a quick glimpse into our universe's beginning to see if it could shed some philosophical light on our overtaxed lives. This week let's look at the world around us - our present - and see if there is meaning here.

Regular readers of this column know - at least I hope so by now! - that our orb is not your average planet.

Below us is a crust that is as relatively thin as the peel on an apple. But were it either thicker or thinner, we wouldn't be here.

We have just the right amount of radioactive stuff inside the planet to keep it molten and, most importantly, moving. This flawless crawl causes continents to rise, depressions to fill with water, mountains to climb, and an endless recycling of minerals to provide new soil for plant growth.

Our optimal liquid outer core provides us with the perfect magnetic field, an invisible force field that protects our planet from lethal solar winds.

Around us we have the ideal atmosphere for life: just enough oxygen, just enough nitrogen, just enough carbon dioxide. You couldn't order in a better mix. And the mass of our planet - which determines our gravity - assures we won't lose the good gases, and we won't hold on to the bad ones.

And don't forget that unseen blanket of ozone way above which stands guard against destructive ultraviolet rays that flood our solar system.

We have the perfectly sized neighbors, perfectly placed about us to help us maintain our perfect orbit and tilt and rotation. From the sun itself, out to the Kuiper Belt and beyond, everything is placed exactly where it should be for there to be life right here on this blue dot.

We circle a pristine star which itself is in a pristine position in a pristine galaxy in a pristine part of a galaxy cluster. Alter any of those things and we are not here.

And these are not isolated phenomena. Many of them are perfectly orchestrated works in progress involving many hypercoordinated events.

For example, many moons ago a small planet smacked into proto-Earth at just exactly the right velocity, and the Moon was created from the debris. This collision perfectly thinned our crust and gave us extra radioactive stuff. The new Moon slowed us to a comfortable 24-hour spin. It provides us with life-giving tides. It stabilizes our spin so we barely wobble, and we sure don't fall down.

As described in an earlier article, the fact that Earth has maintained a relatively constant temperature for billions of years required that our warm carbon dioxide blanket gradually thin as our sun gradually heated up. That thinning involved the perfect coordination of plate tectonics, erosion, spin, climate changes, crustal make-up, plant life, etc. If any of these players did not to show up: game over.

You would be hard-pressed to find any thing, any event, or any time from the big bang until now that is not absolutely optimal for human life right at this moment. I have no room to mention the hundred-plus other parameters that make life possible here and now, but when you look up, down, and around you are seeing the ne plus ultra, perfection itself.

And this is just what we happen to know at the moment. How much more is there around us that we do not yet know, but without which there would be no life?
So much for presenting a limited amount of evidence. Here are some questions you and your philosophical friends can wrestle with this week:

What does all this say about our existence? Were all those events for the last 13 billion years, all our perfect laws of nature, all our surroundings, all those intertwined events, all those… well, everything just an endlessly long train of random mistakes that led to our inconceivably perfect home? Or was it designed this way? Is Earth a purposeless boo-boo? Or is it part of a grand scheme from the "Beyond" we talked about last week?

Next week it will get dark. The future of our universe in some eyes is nothing if not absolutely bleak. Or is it? Tune in next week for what our future may tell us about ourselves.]]>ritter777@gmail.comNone2006-07-09T18:46:12-07:00http://www.firstlightastro.com/skiesabove/files/212909ef376294cef93623be7a7027f9-78.php#unique-entry-id-78http://www.firstlightastro.com/skiesabove/files/212909ef376294cef93623be7a7027f9-78.php#unique-entry-id-78Bleak. Dark. "Creepy," I actually heard one astronomer portray it. Those are descriptions of the future of our universe from some of the smartest people in the world. How can that be?

For the last two weeks here we've discussed the distant past of the universe - and saw that it was very good - and our present - and saw that it is an astonishing work of art.

But the future of our universe doesn't seem so rosy. There are some definitely dreary things coming our way, and we need to face them.

If we don't destroy ourselves in the near future - a very, very likely possibility - we still have to worry about "the inevitables." For example, we are long overdue for a meteor or comet strike. One well-placed city-sized rock hitting this place at 40 miles a second can lower the curtains on the entire human race.

Our Moon - a perfect partner presently - is slowing us down. Before you know it, our days will be 30… 40… 50 hours long. The resulting temperature extremes will be frightening and spell doom for much of life.

Certain death will come in just a couple dozen million years when the sun gets hot enough to boil away the oceans. Our perfect home will be dry and lifeless.

Escape to another planet, you say? Not likely, but let's pretend. Even if we could colonize another planet like Mars, the sun, our energy source, will eventually completely die out.

Then go to another star! Even if we had the means to get there, there isn't a star around us for 100 light years that has an earthlike planet. And even if we could get to a proper star farther out than that, that star is doomed as well.

Then we could starhop for eternity! No - seriously - every single star out there will eventually go belly up.

Worse, the universe is expanding faster and faster. So what? As the universe accelerates, star formation becomes impossible. Nothing can collect to form new stars or planets.

Bottom line: The universe, whether we like it or not, is destined to be cold and dark... and lifeless. The days of our lives are numbered.

Well that's just great! After all this perfection, death!

If this were a mere science article we could end it here. But this is part three of our scientific/philosophical look into a great story, our story. Time for the thinking caps!

If there is nothing but dark death ahead, where is hope then? Where is purpose? What is our destiny? In our first part we saw a beginning to it all, and deduced that there is something beyond space and time, beyond our universe.

Last week's column indicated that this home of ours is perfect beyond all imagination.

There are at least two conclusions we can make from all this. One goes like this:

We really don't know everything about the beginning, and can never know about anything "beyond" our universe. Anything would be pure speculation. And this present of ours could be just the end result of a near infinite number of purely random causes and effects. We just happen to be lucky winners in a cosmic lottery with odds trillions of times worse than any old manmade lottery.

And that bleak future is exactly what's expected from a purposeless, dark, "creepy" universe. Let's just eat, drink, and be merry...

Alright. Another view, on the opposite end, goes like this:

There was a beginning, hence, because of cause and effect, there was a Beginner. There is a "beyond," outside of time and space that we are expanding into. This transcendent Beginner, not bound by time and space, designed and organized this universe, and for the last 13.7 billion years formed and shaped and crafted it so that we humans could enjoy these brief years we have here.

A bleak future? Maybe not. Maybe this Beginner, this Master Planner, never intended this universe to be our only home, just our first. Maybe this One has another place, beyond these four dimensions of time and space, prepared for us. Perhaps our short lives here continue elsewhere.

Socrates told us "the unexamined life is not worth living." Do you see how those "cold, clinical sciences" might help us examine the Great Mysteries of life? Admittedly, there is just a small space here to discuss these profound thoughts and ideas. But I hope you were at least encouraged to start looking more deeply into life's great questions.

Until next time, clear skies - and clear thinking!]]>ritter777@gmail.comNone2006-07-23T18:43:07-07:00http://www.firstlightastro.com/skiesabove/files/52aed660e3b275a60b90b338f7c0d525-77.php#unique-entry-id-77http://www.firstlightastro.com/skiesabove/files/52aed660e3b275a60b90b338f7c0d525-77.php#unique-entry-id-77Still planning a trip this summer? Interested in a new night sky? If you answered "yes" to both of these questions, this column is for you.

The only way you will not get a new sky when traveling is to make sure you end up on the exact same latitude as you started. For example, if you are going from San Diego to, let's say, the vacation hot spot of Esfahan, Iran, your sky will be exactly the same.

Why? Merely moving directly east or west on the same latitude does nothing to your sky. The only difference you'll notice is that the sun rises sooner or later, which is nothing to write home about.

But will you be traveling north or south? Then part of your travel plans might include looking up and celebrating the difference. Allow me to try to explain why.

Use your mind's eye and see the planet spinning around like a top. Someone standing on that fat line around the middle called the equator gets to see the entire sky over the course of a day. Of course the sun interferes during the daytime, but the fact remains: That person's view sweeps around the entire heavens like a light in a lighthouse.

Sadly, some freezing chap at the North Pole essentially stands in one place and, through a 24-hour period, makes one very slow pirouette. But that poor gentleman only gets to see the northern part of the heavens, what is called in astrospeak the North Celestial Sphere. The whole southern part of the sky is blocked by a big rock, what is called in astrospeak the Earth.

One standing on the South Pole has just the opposite problem. But only the southern stars are visible from there. No North Star, no Big Dipper, no Orion. Our big rock blocks them all.

Those are the extremes. Now, for more realistic examples.

If you are traveling north on your vacation, you are getting closer and closer to our frozen friend on the North Pole. Your skies will start looking more and more like his.

The southern constellations like Sagittarius and Scorpius will begin to disappear below the horizon. The stars will rise and set at sharper and sharper angles. The North Star, Polaris, will be suspended higher and higher above your head.

In fact, you can use Polaris to judge approximately how far north you have gone. We who live around San Diego hug the 32nd parallel. For a skywatcher that means that the North star, Polaris, is about 32 degrees above the horizon.

If we traveled to Vancouver, British Columbia, at 49 degrees of latitude, the North Star at night would be - you guessed it - 49 degrees above the horizon.
Go all the way to the North Pole and Polaris is now directly above your head.
And on the Pole the stars don't rise or set. What? They travel about a winter sky in vast sweeping circles around the observer's head. There is a paradigm shift that would take time getting used to! (The sun blots out the stars during northern summer.)

Travel south and things change, as well. The North Star sinks lower and lower toward the horizon. The stars look more and more like they are rising straight up out of the eastern sky like fireworks before the blast.

If you travel to the equator itself Polaris is all the way down on the horizon, and you will, over the course of a year, see all 88 constellations.

Of course traveling further south will afford you a better view of all those southern constellations, and the northern ones will begin to disappear below horizon.

But two things will become noticeably clear to a careful observer. One is that there is no South Star, no Polaris of the southern skies. People living "down under" must use a group of stars to figure out direction and latitude.

And the stars rise and set in a strange fashion for our eyes. Instead of rising in the east and sweeping an angle over the southern skies to set in the west, stars will rise in the east and cut out a swatch of sky northwards to set in the west.

Wherever you go, take some time from your busy vacation schedule, go outside and look up. There may be a whole new heaven awaiting you.]]>ritter777@gmail.comNone2006-08-09T18:40:12-07:00http://www.firstlightastro.com/skiesabove/files/f440c63a936b4adf359254603443175b-76.php#unique-entry-id-76http://www.firstlightastro.com/skiesabove/files/f440c63a936b4adf359254603443175b-76.php#unique-entry-id-76Driving up Interstate 15 recently, just north of Escondido, I saw on the distant horizon my destination and thought, "Dang, I still have one long way to go. Glad I brought my iPod!"

But my target was a mere 45 minutes away - with good traffic, anyway.
Traveling around our expansive country on vacation or business, whether by plane, train, or automobile obviously takes more time, from hours to days, and a lot more patience.

What if we could speed up these trips? What if we could go as fast as, say, the Space Shuttle? The Shuttle dashes over our heads at more than 17,000 miles an hour. That would allow us to cover the US in just over 10 minutes. That, my friends, is fast. At this great speed, it takes just about an hour and a half to go around this entire planet. Going that fast would cut travel time anywhere to nothing. Space travel to other places might be reasonable and fun! Or would it?

What about traveling to the nearest heavenly body, our Moon? How long would that take, going at a more realistic speed of about 25,000 miles an hour?

An imaginary straight trip to the Moon at that clip, not including slowing down for parking into lunar orbit, would take about 10 hours. Not too bad. That would be like a nice drive to northern California.

What about to Mars, our nearest neighbor? At a distance of about 50 million miles at close approach, you'd think it wouldn't take too long to get there, maybe a couple days, maybe a week. Well, if we could shoot an idealized straight-line journey to Mars with no stops or slowing down it would take - ahem - about 80 days.

How about the sun, that big ball in the sky, so close you can almost touch it? Try a little more than 5 months! And that is a mere 93 million miles - one astronomical unit (AU) in astrospeak.

The outer planets are way farther than the sun. For example, a straight-line trip in our imaginary Shuttle to Jupiter, that bright object in the western skies after sunset, with no potty stops, would take over two years.

The Kuiper Belt, you ask? To make it to that new hot spot for planet-searching, just beyond Pluto's orbit, our Shuttle would have to fly for over 20 years. Twenty years. Imagine taking off in 1986, when Ronald Reagan was president, and bee-lining yourself at 25,000 miles an hour directly out to the semi-congested area just beyond the main planets - and just now getting there.

And that isn't even the edge of the solar system!

Want to go to the nearest known star outside our system? Proxima Centauri is that star, and it's about 4.3 light years away, meaning it takes light that much time to get to it. But light travels at over 186,000 miles a second. Our vastly slower Shuttle would take - sit down - over 115,000 years to visit our "nearest neighbor."

Can you begin to conceive of the nearly inconceivable distances of space, and the nearly impossible idea of distant space travel?

Let's up our Shuttle speed to half the speed of light. In order to cross our Milky Way galaxy, our home of over 100 billion stars, even at our new incomprehensible speed it would take about a quarter of a million years!

To go to the nearest other major galaxy, Andromeda, visible in northeastern skies later tonight, would take our Super Speedy Shuttle more than 5 million years.

And this is just our local group of galaxy neighbors. The known visible universe extends out in all directions another 13.5 billion - that's billion with a "b" - light years in all directions!

I don't know about you, but once we get beyond the solar system any journey, even at breakneck speeds, escapes my tiny imagination.

Next time I see my destination off in the distance, just a dot on the horizon, I'll remind myself that it could be a lot worse. That may make a drive on the 15 a little more bearable. Maybe not.]]>ritter777@gmail.comNone2006-08-20T18:37:31-07:00http://www.firstlightastro.com/skiesabove/files/808f6938c55f31b68a942d83d19a0369-75.php#unique-entry-id-75http://www.firstlightastro.com/skiesabove/files/808f6938c55f31b68a942d83d19a0369-75.php#unique-entry-id-75Redshift. Blueshift. Near star. Far star. Sounds like a lame attempt to start off a new Seuss book. But what is this talk from astronomers about things redshifting or blueshifting? What's it all mean? And what does it have to do with the Big Picture of our universe?

Let's start off this explanation with a small scale example we have all experienced. When a fast moving car speeds by you, you can hear a rise in the pitch of the sound as it approaches, and a lowering as it passes by and away. NASCAR fans hear this sound effect in their sleep.

This is called the Doppler effect. As the object approaches, its sound waves get smushed together, which raises the pitch. As it goes away from you, the waves in effect are stretched out and the pitch lowers.

But the same thing happens with light! As an object in space approaches, its light waves get smushed. As it moves away or recedes the wavelengths are stretched out. But we cannot hear any effect, obviously. How can we detect this?

We look at the light! There are simple ways in astronomy to examine the light of a star. We spread the light out like a rainbow, so we can see its "spectrum." We see that for a star's spectrum there are some wavelengths missing - there are thin black lines on the pretty rainbow of color. Why they are missing is for another day, but they are missing.

If we see that those missing wavelengths have moved from where they should be then we know the star is moving with respect to us. If they've moved over toward the blue end of the spectrum, we say that the star is blueshifted. Its "normal" wavelengths are shorter, more "bunched up," than when at rest so the light source - here, the star - must be moving toward us. If the missing lines have been moved toward the red end of the rainbow, then the star's light has been "redshifted," stretched out, and the star is moving away.

How far they have moved from their expected "rest wavelength" will determine how fast toward or away from us the star is traveling. You won't actually see a star get redder or bluer; even a star moving at a good clip doesn't shift its wavelengths by much. But it is a handy device for plotting the stars in space and predicting where they've been and where they're going.

However, there is another "shift" that plays a huge role in the life of our universe - the cosmological redshift.

About 80 years ago, Edwin Hubble confirmed something that was puzzling the astronomical community. By studying the light from galaxies all around us, it seemed that virtually every one was red-shifted, they were all moving away from us. Stranger, close-by galaxies were just putt-putting away from us, but the galaxies at great distances were screaming away at great speeds!

How could this be? What are the odds that essentially all galaxies were redshifted? Why wasn't there a random mix of redshift, blueshift, and no-shift? Unless!!!

Unless the entire universe was expanding! The only scenario that explains why everything is moving away from each other, and the more distant things seem to be racing away faster, while the closer objects are in no particular hurry to move away, is a cosmic kaboom.

This was the first proof of a big bang, of a beginning to the universe. But it's a little stranger than that. Get the thinking cap!

Those galaxies aren't being shot through space at those tremendous speeds. They are being carried by space. Space itself is expanding, and has been since the Creation Event.

As space expands it carries everything along with it. You, me, the dog, planets, galaxies... everything.

As the space expands, it stretches out. Light, riding on that fabric of space, gets stretched, too. Like the unfolding of an accordion, the wavelengths of light get stretched out to longer lengths. This, in effect, shifts those photons toward the red end of the spectrum. Thus, the light of essentially every galaxy out there is being redshifted. But not because of the common Doppler redshift explained above. This here is the Mother of All Redshifts - the "cosmological redshift."

The cool thing is not just that this all shows we had a beginning to the universe, although that truly is awe-inspiring. But taking all the redshift data, and crunching the bejeebers out of them, we can nail down a time when it all began, which is nearly 14 billion years ago. That's impressive, as well.

Did this shed a little light on some cosmic questions you had. Hope so. Until next time, clear skies!]]>ritter777@gmail.comNone2006-09-03T18:31:13-07:00http://www.firstlightastro.com/skiesabove/files/9610ff1ddd009d22139296c8e342a37c-74.php#unique-entry-id-74http://www.firstlightastro.com/skiesabove/files/9610ff1ddd009d22139296c8e342a37c-74.php#unique-entry-id-74Ah... it's back-to-school time. How about we have a friendly little astronomy quizzie to put us all back into School Mode? Those of you who read here regularly know that this is not a genuine quiz so there is no need for clammy hands and shortened breath. And there are only three true-or-false questions. So sit back and enjoy a little exercising of the grey cells.

1. Only a select few people on the planet can see an eclipse.

OK, admittedly that was sort of a trick question. I should specify lunar or solar eclipse. Few people see a solar eclipse in a lifetime; most everyone on the planet can see a lunar eclipse though. Why?

An eclipse is basically one body casting a shadow on another. If the Moon squeezes in between the sun and us, for example, it can cast a shadow somewhere on Earth. But it's just a pinprick of a shadow, sometimes only tens of miles across. And the shadow races across the surface of our planet at about 1000 miles per hour.

This is a solar eclipse, and it is an amazingly ethereal phenomenon to observe. But you have to be in the exact right place to be in "the umbra" or full shadow. To see one you will probably have to get up and go somewhere. If you are not content on actually traveling to see one, be patient, your area probably will get a total solar eclipse in the next three or four centuries.

A lunar eclipse is a different duck. When we cast a shadow on the Moon, it's no tiny pinprick. Our shadow can cover the entire Moon! The benefit of a lunar eclipse is that everyone on one side of the earth can see it. It's a free show from your own backyard. And if you miss one you only need wait another 6 months or a year to see it again. In the average lifetime one can see literally dozens of them.

2. Your date of birth determines which astrological sign you are.

This really is an astronomy-related statement! We are told that the moment of your birth determines what "sign" you are; whether you are Capricorn or Aquarius or Leo, etc. And your sign is determined by which constellation the sun is in at that special moment.

But the charts that are used to tell us what our sign is were made thousands of years ago. Here's the problem. Since that time our planet has wobbled ever so slightly in its spin position - not much, but enough to "shift" the constellations through the calendar a wee bit.

So, for example, on January 27 a few thousand years ago we would have found the Sun occupying the region in space dedicated to Aquarius. Since then, though, our wobble has shifted the January 27 sun into Capricorn.

Meaning, although the newspaper horoscope will peg a baby born then as an Aquarian, the sun was really in Capricorn at her birth. So what sign is she - Aquarius or Capricorn? Good question. And the same dilemma follows for nearly everyone reading this now: Nearly all of us are off by one sign. More than 90% of the people reading horoscopes have been reading the "wrong" sign. Hmmm...

3. Pluto is a planet.

This is an emotional subject as of late! Since its discovery in 1930, this little guy has been considered a planet. And why not? It was the next heavenly body discovered beyond Neptune; it should be a planet.

But wee Pluto has been trying to tell us something since those early days.

For one thing, it is a very, very small orb, smaller than our country let alone our Moon and a handful of other heavenly objects not considered planets. Its orbit is way wacky; it's outside the regular plane of the rest of the planets, and sometimes it's closer to the sun than Neptune.

And for the last ten years we've seen a whole truckload of other Pluto-like objects out in the deep areas of our solar system, beyond Neptune, seemingly filled with icy bodies of all sizes, one bigger than Pluto itself.

Which is why it was agreed by voting astronomers recently that maybe Pluto should just be considered the "first found" of those trans-Neptunian objects, aka Kuiper Belt Objects.

But the controversy isn't over. A small but vocal group of astronomers who want to keep poor Pluto as a proper planet is demanding a recount. So stay tuned, maybe we won't need to downsize the little guy - yet.

Get all three correct? If not, no worries. None of these statements were too black and white. That's the nature of science; lots of gray, a little black and white. Until next time, clear skies!]]>ritter777@gmail.comNone2006-09-24T18:26:23-07:00http://www.firstlightastro.com/skiesabove/files/dc9701d0a1974a480064446130d47471-73.php#unique-entry-id-73http://www.firstlightastro.com/skiesabove/files/dc9701d0a1974a480064446130d47471-73.php#unique-entry-id-73Let's take a late summer stroll down the lane, that cloudy lane of stars bisecting the night sky - the Milky Way.

This week is a good week to do so, weather and light pollution permitting. The Moon is below horizon until the wee hours of the morning and won't blot the sky with its intense brightness.

The Milky Way is easy to find, assuming you are not near an auto mall or casino whose lights turn night to day. It is the faint band of light stretching from the southern horizon across almost directly overhead and into the north.

It is of course our home galaxy seen edge on. We live in the disk of this collection of hundreds of billions of star and can see it all year long. But the summer Milky Way is especially easy to see because at this time of the year our night sky faces the more densely populated center of the galaxy. Our winter sky faces the dimmer suburbs of the galaxy.

The southern sky is a fine place to start our skywalk. (You can customize your own star chart at skytonight.com to follow along visually.) It is in the southern skies where the Way is brightest, in the constellation of Sagittarius. And in that teapot-shaped constellation resides the center of our galaxy. You can't see the billions of stars there, let alone the supermassive blackhole eating away at the very center, because of all the dust. But it's there... trust me.

Scan around the top of the teapot with binoculars or a telescope and you should be able to spot several star clusters and faint nebulae. These are star birth regions similar to the Pleiades and the Orion Nebula.

Follow the Milky Way up into the sky, about two-thirds of the way up. There is a bright star called Altair in the constellation Aquila. Altair is unique in that it spins once on its axis every 6 hours or so. Compare that to our sun, which takes nearly a month to do so and you can see we have ourselves here one speedy spinner. It spins so fast that it is actually about 14% wider at the equator than at its poles.

Nearly above your head, can you see the cross-shaped constellation of Cygnus the Swan? At the "top" of the cross is Deneb, a bright star that pours out more energy in one day than the sun does in 140 years. Take Deneb, Altair and that bright star almost directly above your head, Vega, and you've got yourself the Summer Triangle.

At the foot of the cross await two stars - yes, two. It appears as just one with the naked eye, but that’s only because our eyes cannot resolve them - they are that close. They are Albireo, a binary star system about 380 light years away. If you have access to a scope take a look at them. They are a colorful pair; one is a pinkish-orange, the other a bluish-white.

At the intersection of the cross you might be able to spot another open cluster of stars with the poetic name of M29. Only 4000 light years away the cluster should be brighter than it appears. Then why so dim? For the same reason we can't see the galactic center; objects in the Milky Way disk lose a lot of their light to the massive clouds of dust there.

Follow the path now until you reach familiar Cassiopeia, the Queen, residing in her big zig-zaggy throne in the sky. Need some pure trivia? Travel to Alpha Centauri, one of the closest stars to earth just over 4 light years away, look back home, and you will see our sun as one of the stars in Cassiopeia. Don't laugh! That may win you a lot of money some day on Jeopardy.

Is there more to the Milky Way than this? You bet. This was just an attempt to get you outside and take a wondering look upwards. With a scope or even binoculars you can see all kinds of star clusters and nebulae, single stars and doubles.

Now go, and take a walk through the Way. Until next time, clear skies!]]>ritter777@gmail.comNone2006-10-02T18:23:04-07:00http://www.firstlightastro.com/skiesabove/files/96f334a46496f08006a13d9b59b45351-72.php#unique-entry-id-72http://www.firstlightastro.com/skiesabove/files/96f334a46496f08006a13d9b59b45351-72.php#unique-entry-id-72Answer: This horse rides around all night long, upside down, with only two front legs and no backside, but with one bright and shiny belly button.

Question: Who is Pegasus?

Correct! In the northeastern skies at this time of the year rides the great constellation of Pegasus. Our equine friend is easy to spot. Its body, what there is of it, is that giant square in the sky, called, for obvious reasons, the Great Square of Pegasus.

Pegasus was the famous winged horse from Greek mythology born, as are most winged horses, from the blood of Medusa's head with just a couple tablespoons of sea foam tossed in. The famed horse's exploits are numerous and, unique to most characters of ancient mythology, relatively free of wrongdoing. On the contrary, it appears that most everyone got along with Pegasus and had nothing really bad to say about our benevolent beast of burden.

The whole of the constellation Pegasus consists of only the front of his body. The entire hindquarters are missing. And he is upside down. But let’s focus our attention now on the most obvious characteristic about the constellation, which is, as I mentioned above, the big fat square of stars. You cannot miss it. It is in the eastern skies in the evening now and there are essentially no stars in the middle of the square, so it stands out like a sore thumb - a gigantic, squarish sort of sore thumb.

Of course, other cultures saw different things in that cosmic quadrangle. The Hindus see the Great Square as a lunar mansion, a nakshatra, one of 27 resting places for the Moon as it travels through the skies.

According to Julius Staal is his book "The New Patterns in the Night Sky," the Arawak Indians of Guiana in South America saw the great pattern as a monstrous barbeque grill!

Let's take a closer look at those four stars in our horse's body. In the southwest corner of the Square, farthest to the "right" as it rises in the evening, is Markab. Though just a pinprick in the sky, it is one energetic star. Weighing in at almost 6 suns, it outshines our own star by nearly 200 times. This is a star best seen at a distance.

The "top" star of the Square is Scheat, an old dying red giant of a star nearly 200 light years away, but nearly 200 times bigger than our sun.

At the bottom is the star Algenib, a named derived from the Arabic al janah, "the wing." It marks - you'll never guess – a wing of Pegasus. This is one bad star. It is over three times hotter than our sun (that's really, really hot in Starville) and pours out more energy than 2500 suns! Thankfully it's over 300 light years away. We can all sleep better because of that.

The last star of the Great Square of Pegasus leads a duel life. It is known by some as Sirrah, from the Arabic, Al Surrat al Faras, "the Navel of the Horse." Honestly, I didn't know horses had belly buttons. Now that I think about it, I guess they have to.

But it also known as Alpheratz, and with that name belongs officially to the constellation of Andromeda. How can that be? A corner of the Great Square of Pegasus is actually in Andromeda? It appears that Princess Andromeda needed a head, of all things, so the star's main role today is to be a melon for her royal highness. So speaks modern astronomy. Sorry Pegasus!

Sometime in this next week go out to the starfields and take a look at our equine friend, what there is of him. Then consider yourself one constellation closer to fully knowing the night sky.]]>ritter777@gmail.comNone2006-10-16T18:20:15-07:00http://www.firstlightastro.com/skiesabove/files/575068c3054a9f0cf0bbfc66054df4a1-71.php#unique-entry-id-71http://www.firstlightastro.com/skiesabove/files/575068c3054a9f0cf0bbfc66054df4a1-71.php#unique-entry-id-71
But what about our attempts to decipher the entire rest of the universe? What about everything beyond our tiny home? What senses do we use then to make sense of it all?

How have we discovered so much about the workings of the cosmos, from the birth of the universe to the deaths of distant blue giants, from the great superclusters of galaxies to local volcanic activity on Io?

We cannot reach out and touch the very first stars, we cannot hear the explosion of that hypernova. We cannot taste the frozen surface of Europa, nor can we smell the great red giant star in Orion, Betelgeuse, the Armpit of the Giant. I'm not sure I'd even want to.

So what sense are we left with? Sight, of course. We can see the great starry night sky assuming we live in an area not polluted with light. But our eyes are small and insensitive. Their openings, those black dots in the irises called pupils, are just millimeters across. And the back of the eye, which absorbs the light, only processes about one percent of what hits it.

This is more than enough for everyday life, but miserable for studying the universe beyond our night sky.

Moreover, our eyes are sensitive only to certain wavelengths of light, those that make up what is called the "visible spectrum," the colors of the rainbow. There is an entire spectrum of wavelengths, on both sides of the visible patch, full of information that our eyes cannot descry.

What to do?!

Enter the telescope. This profoundly important tool has changed the study of the heavens in ways indescribable.

The telescope is essentially an extension for our eye; an upgrade for those of us who want to see the whole universe. You probably have seen the standard optical telescope. It nothing much more than a "light bucket." It gathers immensely more light than our puny peepers can, and focuses it into the back of our eye so we can see those very distant, very dim objects.

Look at the modern scopes all over the world. They have light-gathering mirrors in them meters across. And if you observe closely you'll notice no one looking through any eyepieces. That's because they are all fitted now with special devices called CCD cameras which can capture not the wimpy 1% of the light our eye gets, but nearly 100% of it. "Really big, very sensitive eye extenders" you might call the modern scopes.

OK, so we learn about the universe by seeing it. And we see way better with telescopes. What about all those other wavelengths, the ones we cannot see? How can we capture and "see" them.

We devise other telescopes to "tune into" those elusive wavelengths! For example, we have gamma ray scopes to gather that wavelength, then translate the info into the visible so we can "see" the gamma activity up there.

There are also X-ray and ultraviolet scopes to complement that stronger and more dangerous part of the spectrum.

On the weaker side of the spectrum, we have infrared and radio telescopes. You may have seen the radio telescopes; they look like giant dishes.

Because of the nature of radio wavelengths - they are really long - the laws of physics demand that the dishes be huge to gather those photons into a proper focus. For us to see radio waves ourselves, our eyes would have to be enormous, way too big to get through the door.

All these "eyes on the skies" tell us how objects in the heavens are born, live, and die, what they are made of, where they are going, how they are changing over time, how hot or cold they are, and so on, and so on.

Listen carefully the next time there is a big discovery in the cosmos. Try and hear exactly what kind of scope was "looking" into the heavens, using its eyes and sense of sight to help us better understand this wondrous universe of ours.]]>ritter777@gmail.comNone2006-10-28T18:16:08-07:00http://www.firstlightastro.com/skiesabove/files/b3acf8be5d9cf9b7f326437a935d7de4-70.php#unique-entry-id-70http://www.firstlightastro.com/skiesabove/files/b3acf8be5d9cf9b7f326437a935d7de4-70.php#unique-entry-id-70To be sure, there are extremely important events transpiring around the globe; problems in North Korea, the Middle East, and the Persian Gulf, politics, world hunger, and so on and so on.

So, on the Importance Scale, next week's cosmic event is probably not in anyone's Top Ten. But it is one of those rare phenomena that bears considering. And it is kinda cool.

Next week, on Wednesday the 8th, Mercury will perform a celestial feat that won't be duplicated until 2016. It will cross in front of the Sun in something astronomers call a "transit." And we on the West Coast can see the whole thing! Yay for us!

As you know, Mercury is a tiny planet that hugs the Sun at less than half the distance we are. And just as the laws of planetary motion predict, our little neighbor speeds around the Sun in a fraction of the time we do - a mere 3 months. That is mercurial to say the least.

Now if it moves that quickly, and if it is between the sun and us, this "transit" thing should happen all the time, correct? Not necessarily. Poor Mercury's orbit isn't exactly lined up with ours. Its "orbital plane" has been knocked out of alignment with most of the rest of the planets, so it is most often above or below the Sun as it passes between.

But next Wednesday, from about 11 AM to about 4 in the afternoon, it is lined up just right for us to see its dismal, pathetic attempt to eclipse the enormous Sun.

Only those of us living on the West Coast - or someone stranded in the Pacific between the mainland and Hawaii - will be able to see the whole show.
But of course we can't go out and just start staring at the Sun in hopes of seeing a tiny, almost imperceptible dot cross in front of it. You must use some sort of instrument to help you.

One can use the traditional binocular-and-a-piece-of-cardboard trick (for details see: http://www.space.com/scienceastronomy/solarsystem/solar_eclipse_view.html). Or you can purchase solar filters for your scope, making sure, of course, that the filters are the type that are placed in front of your scope. Filters put on the eyepiece alone pretty much guarantee a small fire and the soon purchase of a white cane with a red tip.

These filters are available online or locally at Oceanside Photo and Telescope, and can be used even after the transit to see sunspots as we head towards higher solar activity in the next several years.

But, you may say, I have no binoculars, or scope, or money for filters! Well, alrighty then, there is another option. You can contact your local astronomy club and ask them to set up something. And the very same Oceanside Photo and Telescope will have telescopes set up all day Wednesday in front of the store - weather permitting - so you can see the transit for yourself.

So, bottom line, there are no excuses for missing this rare event!

In the next weeks after the transit, as a follow-up, you might try to spot Mercury in the predawn skies starring in its next role as Morning Star.

One more bit of trivia. What is the only other planet allowed to transit the Sun? Why, it's Venus of course. A planet has to be on an inside lane around the Sun to try and come between the sun and us. Only Mercury and Venus fill that requirement. But alas! Venus won't be crossing that great ball of fire until 2012. So make the most of next Wednesday's transit!

Until next time, clear skies!]]>ritter777@gmail.comNone2006-11-12T18:09:27-08:00http://www.firstlightastro.com/skiesabove/files/36e6e016762b279205088e814ecbfae5-67.php#unique-entry-id-67http://www.firstlightastro.com/skiesabove/files/36e6e016762b279205088e814ecbfae5-67.php#unique-entry-id-67Most astronomers - but not all - do their observing at night. It is then that the skies are see-through black and the objects that make up our starry heavens are at their best.

But once the sun comes out, observing time for those astronomers is over. It is then of course that our skies metamorphose from transparent and black into translucent and blue.

So why is the sky blue?

This question is a classic, but few people really know the answer. It's almost as if it were enough just to ask, but not to find out. Let's answer it now.

One reason for the blueness of the daytime skies that I have heard many times is that the sky is reflecting the oceans. Good guess, but if we took that to its logical end we'd have to ask why the sky isn't also brown and green and white, other colors which dominate the Earth's surface.

I'll bet we can find another, more logical answer. Let's try. The sky is blue during the day, so the sun must play some role. Here are another couple helpful clues: There is no blue sky on the Moon, ever. And have you noticed that when the Shuttle astronauts are working on things up there, they are being bathed in sunlight, but the "sky" all around them is pitch black? So the sun must have an accomplice; it cannot be working alone.

Immediate hypothesis? The sun and an atmosphere are needed to make a blue sky. The two work together somehow to bathe us in a sea of blue.

Consider this also. The Sun, as you know, bleeds out all the colors of the rainbow, from deep blue all the way over to the red end of the visible spectrum. Might there be something about the atmosphere that monkeys with just the blue parts of the spectrum sent down from the Sun? If you think so, you would be right.

The photons of light that make up the visible spectrum differ by wavelength. The blue end has the shorter wavelengths, the red end the longer.

The molecules of oxygen and nitrogen that make up our atmosphere are just the right size - that is, incredibly small - to interact with the short-wavelength blue guys. Those photons are absorbed by the air molecules and re-emitted in random directions all over the sky. This happens so much, they are scattered in so many directions, that everywhere we look we are getting hit by those redirected blue photons.

All of this works to give our inquisitive minds the impression that the blue photons are coming from everywhere, and ta-da! the sky is blue.

The other parts of the spectrum come on through with relative ease, but even some of these are challenged if there is a lot of atmosphere to go through. This of course is what happens at sunset.

As the sun sets, the light pouring from it has to travel through a lot more sky - and a lot more schmutz - to get to us. Much of the spectrum gets pealed away from the light stream leaving only the heartiest and longest of the wavelengths, those on the red end, to make it through, and giving us those spectacular sunsets.

You may have noticed that when the sky is smoky from a fire that the sun appears red. Same reason as above: the longer-wavelength red photons get though, the rest are scattered.

And now you know what happens to the stars when the sun is out. This whole effect -the scattering of the blue wavelengths - essentially fills the skies with that familiar blue glow, and the relatively dim stars beyond, still traveling over us, get blotted out. If you could suddenly take away our atmosphere during the day, the skies would be transparent and black again, except for the vicinity of the Great Star, our own Sun.

But then it would be kind of tough to breathe, our blood would begin to boil, and the thrill of seeing the stars during the day would soon be replaced by excruciating pain, followed by death less than a minute later.

I'll settle for studying the stars at night, and keeping the pretty blue skies for the daytime.
]]>ritter777@gmail.comNone2006-11-26T18:04:01-08:00http://www.firstlightastro.com/skiesabove/files/3b0e62f2552c638835153a8e8ec02bcd-66.php#unique-entry-id-66http://www.firstlightastro.com/skiesabove/files/3b0e62f2552c638835153a8e8ec02bcd-66.php#unique-entry-id-66Thanksgiving is sadly becoming just another one of those excuses to get some time off, like Memorial Day. And like Christmas it suffers from so much busy work, from family to food to football, that the entire day can pass us by and we can completely forget to celebrate it.

But now the family is gone, the extra food is in the Tupperware, and the football is… well, that will never go away I guess. So let's have our own mini-Thanksgiving! And we'll concentrate on the cosmos - specifically the Sun and Moon - to see what there might be to be thankful for.

There of course is a poetic way to look at this dynamic duo. The greater light to rule the day and the lesser light to rule the night have been revered - sometimes as gods - for millennia. They are amazingly reliable timekeepers and season markers. And there is something about the sunrise and sunset, or the crescent Moon sinking in the west, or one rising full in the east, that has this way of drowning some of us in thanksgiving and praise.

But allow me to put on a pair of cold, clinical scientific spectacles and see if there might be even more in those celestial spheres to be thankful for.

When we look deeper into the Sun and Moon we see that they are the exact same size in the sky, a phenomenon that occurs on no other planet in the solar system. This allows for those mind-altering solar eclipses, but is a wonderful thing in its own right.

It also means they are both at just the right distance to be life-sustaining orbs and not the killers they could be. What?
We don't want the Sun to be bigger or smaller in the skies above. "Bigger" could mean several things; that it is really a larger ball of gas or it is the same size as our Sun, just closer. Both would spell doom.

A naturally bigger star would burn much faster, spew out more of the lethal wavelengths of light like ultraviolet and x-rays, and die much sooner. Nothing but bad news in that.

And if our Sun appeared bigger because it was closer - closer even just by just millions of miles - we'd be headed for a heat wave that would shut this planet down. (see Venus)

Contrariwise, we don't want our Sun smaller in the sky, as in farther away. We'd freeze. (see Mars) And a legitimately smaller star, one with a smaller radius, would not give us enough energy to live. We'd have to snuggle in closer to that fire to stay warm. But in doing that the small star would, because of the laws of physics, slow down our own rotation to a near stop. And daytimes that last dozens and dozens of hours followed by equally long nighttimes are not conducive to life.

The Sun is not too big, not too small, not too close, not too far - and I am thankful for that.

And we do not want the Moon any bigger or smaller. It was much closer and bigger in the sky when it was first formed more than 4 billion years ago. Back then our planet spun so fast that our days were about 5 hours long! Winds were breakneck. And the Moon, after its miraculous formation, must have been a terrible and awesome sight in the sky, very close and thus many times bigger.

But through the eons the Moon has been slowly moving away from us, diminishing in apparent size. During this time it has tugged on us with its own just-right gravity because of its just-right mass to slow us down to a just-right 24-hour spin.

It will continue to get farther away and smaller in the sky, and will also continue to slow us down. But longer days and nights mean more extreme temperature changes, from way above 100 degrees to well below freezing. We are here at exactly the right time.

The Moon is not too big, not too small, not too close, not too far - and I am thankful for that.

There is a lot more about those two heavenly bodies that would give us a greater appreciation of them both. Suffice it to say now that they are wonderful daily reminders of how, in spite of our attempts to ruin the place, we have truly been blessed with a wonderful home.]]>ritter777@gmail.comNone2009-05-18T17:47:13-07:00http://www.firstlightastro.com/skiesabove/files/f091b24305c98230d4a895f4d44a0402-65.php#unique-entry-id-65http://www.firstlightastro.com/skiesabove/files/f091b24305c98230d4a895f4d44a0402-65.php#unique-entry-id-65Has your body ever suffered from inferior conjunction? Don't know? Well there is one body experiencing that phenomenon - today as a matter of fact. It is tiny Mercury. But what exactly is this condition, and do we have to worry about catching it?

Inferior conjunction is merely a term which tells one about the position of one body with respect to two others. Some readers may recognize the term "conjunction" from phrases like "The planets were aligned; they were in conjunction." It is a term derived from the Latin word meaning "connected," which is how two heavenly bodies look when they are lined up in the skies.

In today's event Mercury lines up with the Sun, passing in front of our star, or as close as it can. The two are in conjunction, but why the "inferior"?

Mercury and Venus, being on the inside lanes of our solar system race course, can actually line up with the Sun twice, once as they pass between us and the Sun, and once again on the far side as they pass behind our star.

The inside alignment is called inferior conjunction. That more distant alignment is called superior conjunction.

The outer planets (Mars, Jupiter, et al.) only get to be "in conjunction" with the sun - no inferior or superior is involved. They can only be aligned with the sun when on the far side of the sun; they never come between us and our star.

And when those outer planets happen to be on the opposite side of our planet when compared to the sun we get yet another term; those planets are then in "opposition."

You may be curious as to why little Mercury and Venus do not often actually pass directly in front of the sun when they are in inferior conjunction. (Mercury missed doing so today as a matter of fact.) It is for the same reason that the Moon, when it passes in front of the sun every month, does not always give us an eclipse.

The orbits of Mercury and Venus compared to our orbit are not perfectly lined up. Sometimes the planets pass just "below" the sun, at other times they pass "above." Occasionally they do pass right in front of the sun, appearing as tiny dots crawling across that brilliant face. That is called a "transit."

Had your fill of new astronomy terms? But I didn't even mention western or eastern quadrature, or greatest western or greatest eastern elongation. Or eclipse or occultation or the ever-amusing syzygy! Alas!

All right then. Maybe we can line them up for a future article. Until next time, clear skies!]]>ritter777@gmail.comNone2006-12-12T19:29:50-08:00http://www.firstlightastro.com/skiesabove/files/5d5b7aac68bab482567166fc2192150d-64.php#unique-entry-id-64http://www.firstlightastro.com/skiesabove/files/5d5b7aac68bab482567166fc2192150d-64.php#unique-entry-id-64The winter skies are finally making their evening encore performances after their summer dormancy. And perhaps there is no constellation more recognizable among the lot than the Great Hunter, Orion.

Today we'll look at that part of the sky through our poetic, myth-loving spectacles. When we get together next time we'll analyze the great stars and nebulae through our goggles of science.

Orion is by far one of the most readily identifiable plots of the winter heavens, rising now in the eastern skies in the early evening. Its great quadrangle of stars, Orion's body, bisected by the bright triad of stars, his belt, is a story waiting to happen. And all over the globe there is no shortage of sagas.

The traditional western stories from the Greeks involve, of course, Orion the Hunter. And although there is just one hero of the constellation there are many stories that got him there.

Orion, by all accounts, was one big, handsome guy. His birth certificate shows that he is the son of Neptune and the nymph Euryale. At least that's how one of the stories of his genesis goes. And his foremost skill, the one he is immortalized for and the one that could get him in trouble, was hunting.

On one of his violent exploits he found himself on a stopover in Crete where he met Diana, the goddess of the Moon, who herself was a gung-ho hunter.
But, Apollo, the brother of Diana, knew the reputation of Orion as a womanizer and was not about to let his sister become Orion's latest conquest.

So the sly Apollo passed the word to Mother Earth that Orion had been bragging about being able to put down any animal on Earth.

This didn't sit well with Mom. In one version of his demise she produces a mighty scorpion, Scorpius, who does Orion in.

As per the dismal Diana's request, the gods allowed her friend to be immortalized in the heavens. With his dogs, Canis Major and Canis Minor, by his side, he stands there on the great river Eridanus. And to keep him from dropping off in boredom, he is placed face to face with the Great Bull, Taurus. When he is finally going to get around to slaying the Bull is anyone's guess.

For the record, Scorpius got a place in the sky as well, opposite Orion, as a warning to future Orions not to get too cocky.

But the stories don't end with the Greeks. Let's see what others have to say about that piece of cosmic real estate.

Another great culture, the Egyptians, placed Osiris there. He was the God of Light to the ancient Nile-dwellers. His naughty brother, Set, the God of Darkness, tricked Osiris into getting into a coffin-like box. He should have seen it coming. Alas! Set nailed the box shut and Osiris sufficated, shuffling off his immortal coil.

Even though Isis, his wife, found out about it, it was too late. Before anyone could help, Set cut Osiris into fourteen pieces and scattered them all about.
Isis gathered all the pieces together in a story the details of which are too disturbing even for Cold Case Files. Suffice it to say that Osiris' reconstructed remains rose up into the heavens.

Julius Staal's The New Patterns in the Sky gives us a multicultural tour of other "Orions" throughout the world.

In Peru, the Chimu Indians see the central star of Orion's Belt as a criminal, held there on either side by stars called Pata. The four stars that make up Orion's body are vultures waiting to consume said bad man. It was a starry reminder not to misbehave.

The Bororo Indians of Brazil fear and revere the terrifying cayman, a crocodile-like critter and they honor the leviathan in their skies. Its body is our Orion, the tail extending way north to Auriga and the head down into Lepus. It is a magnificently big constellation by any standards.

It doesn't stop there. Orion, being in that particular part of the starry dome above, can be seen by people in both hemispheres. The Hindus, the Chinese, the Dayak of Borneo, peoples of the Marshall Islands, the Maori of New Zealand all have myths centered on the great hourglass.

Moreover, Greek and Roman poets have honored it, and it is mentioned in the Bible, as well.

A fun exercise for school - public, private, or homeschool - is to assign the students the task of thinking up their own myth involving those seven great stars. It gives the kids a chance to use their imaginations and to write and draw, arts we are quickly losing.

Next time: The science behind what is going on up there, and why we are happy to see it all from a great distance.]]>ritter777@gmail.comNone2006-12-22T19:24:51-08:00http://www.firstlightastro.com/skiesabove/files/a9c6b71301b7cf5e68320cc349f4804c-63.php#unique-entry-id-63http://www.firstlightastro.com/skiesabove/files/a9c6b71301b7cf5e68320cc349f4804c-63.php#unique-entry-id-63Scientists used to have no problem disproving the existence of Santa. Their reasoning went something like this:

If the universe is all there is, then Santa Claus is subject to the laws of nature - such as the laws of gravity, energy, entropy, motion, etc.

Being constrained by these laws, he could not possibly do the things he is given credit for - like checking up on everyone, listening to all our requests, visiting millions of households, and delivering tons of presents all in one night.

He would have to break physical laws by achieving incredible supersonic speeds with instant accelerations and decelerations. He would have to expend so much energy in such a small time at such prodigious rates struggling through our thick atmosphere that he could never survive even the first house.

So went some of the patronizing reasoning made by the unbelievers back when science claimed to know it all. They let the "ignorant masses" believe in Santa because it posed no great harm. Karl Marx's younger brother, Onjar, summed up the naturalists' nonSantistic philosophy when he referred to Santa as a "novocain for the people."

However, the last decades have changed dramatically how we view the universe and it has become far less difficult to believe in the "stories" surrounding this man and the possibility that he really may exist.

But first we need a small discussion on space and time...

For millennia, people have been aware of the fact that we live in a three-dimensional spatial world (often referred to as length, height, and width) with one dimension of time (a "straight line" of time with a past, present, and future). To most scientists, that is all that ever existed.

But in the early part of the 20th century there was a great discovery. Through the works of Edwin Hubble and Albert Einstein, it was determined that the universe is expanding. If it is expanding, it must have had a beginning! - an universe-shattering idea at the time. This was a great milestone in scientific thinking and had far-reaching implications, both philosophically and theologically.

One conclusion was that there is more to space than we see. There must be another dimension of space, incomprehensible and unseen, into which we are expanding.

To add to this, recently Stephen Hawking and Roger Penrose took Einstein's theories a little further, concluding that time itself was created at the Beginning, as well. This implies at least another dimension of time outside our own!

To make this all even more mysterious, the last decade has given us the best theory of the birth and life of the universe - the string theory. If it turns out to be true, this beautiful theory requires at least ten(!) dimensions of space to make it work.

Immediate point: There are at least ten dimensions of space and two dimensions of time in "existence." And with this the possibility of the existence of Santa is now not so far-fetched. How?

First, I must use an analogy to help you imagine what extra dimensions might be like. It's thinking cap time!

Suppose there was a flat person (two-dimensional, with height and width only but no depth, like TV news anchors) living on a flat, 2-dimensional surface. An example might be a stick man drawn on the newspaper you're reading now. Imagine he can travel up or down, to the left or right, but not in front of or behind his newspaper "universe." In fact, he is not even aware of space in front of or behind the paper. The newspaper is all there is for him.

You, however, living with three dimensions of space - just one more than he has! - can do wondrous things. You can observe this "flatman," even come right up to him. But he is totally unaware of you - unless you choose to "enter" his newspaper universe.

Imagine that you could do this by putting your finger through the paper (into his realm of sensation). And you could immediately "disappear" just by taking your finger back, leaving his flat world. You still exist, you just cannot be seen. You are with him, yet invisible to him. You can watch him constantly without ever his being aware of you.

Moreover, if you also had another dimension of time, you could do things "simultaneously." For example, you could perfectly converse with more than one "flatperson" at a time. You could also spend as long as you wanted observing a single moment of time in this flatland, like examining a single frame of movie film. For that entire time the flat people would be unaware of you observing them.

With just one extra dimension of time and space, you can do things which, to flat people, seem incredible and miraculous.

Well, science tells us that there really are extra dimensions "out there." Now the "myths" about Santa that seemed so silly are plausible. Here are some examples...

Let's start with where he lives. Legends have it that he lives at the North Pole. But the naysayers will say that we've never seen this House, therefore it doesn't exist. Maybe, however, to our limited 3D existence, the North Pole is the nearest we can get to it! Maybe the house is just north of the North Pole - off limits for us, but existing in another dimension. Just as the newspaper people were right next to - yet unaware - of you, there may be a Santa House right at the North Pole, just beyond our perception.

A Santa who's been given access to other dimensions could, throughout our year, entirely at his leisure, and without being seen or heard, check on us to see if we are being naughty or nice. He could even make a List and check it twice with plenty of time to keep those elves in line!

With special access to extra realms of space and time, Santa could simultaneously visit as many malls as he wants, listening to the pleas of thousands of children everywhere, all day.

Chimneys may be our best, albeit naive, explanation of how Mr. Claus enters and leaves homes without being seen. But he doesn't need any opening at all; he could just enter into our dimensions, leave the presents, then exit back.

This Santa person could visit not only all American and European homes in one single night, but could visit all homes on all the Earth! Although this would be impossible in our spacio-temporal prison, this is a no-sweat effort on his part.

And remember, since his time is not ours, he may be spending an equivalent of "years" of his time doing all this. This would cause him to get hungry and would explain how he could eat hundreds of thousands of cookies and drink oceans of milk in "just one night."

Although science is unable to prove his existence, new scientific discoveries have made it much more easy to believe in him and his seemingly miraculous nature.

Ironically, thanks in part to science, the leap of faith it once took to believe in Santa has been reduced to a step.]]>ritter777@gmail.comNone2007-01-07T19:20:14-08:00http://www.firstlightastro.com/skiesabove/files/85cf228a782147023ad14754896f3fd0-62.php#unique-entry-id-62http://www.firstlightastro.com/skiesabove/files/85cf228a782147023ad14754896f3fd0-62.php#unique-entry-id-62The last time we were together we learned how the great constellation of Orion was not exclusively a European constellation by any means. Peoples on every continent have thrown their own stories and characters up there into that conspicuous part of the sky.

Now we hit the scientific stories, our best insights into what precisely those points of light and fuzzy clouds really are.

Let's start with Betelgeuse, the reddish-orange star that makes up one of the bright corners of the quadrangle, specifically the star in the upper left.

The name Betelgeuse is possibly derived from the Arabic for "armpit of the central one." Some think it might have come from the Arabic for "shoulder" or "hand," but those interpretations don't cause nearly as many snickers.

What we do know is that Betelgeuse is one enormous star, yes-sirree-bob. It is in its red giant stage, the final act in The Life of an Enormous Star. When a star begins to run out of fuel it goes through some crazy death throes, one of which is to expand. Betelgeuse has expanded so much that if we could put it where our own Sun is, it would swallow up all the planets out to Jupiter. That is one big star.

We're happy it's over 400 light years away, because when it finally self-destructs as a supernova in just the next thousands of years, it will spew lethal radiation for hundreds of light years around it, sterilizing the vicinity. Are we completely safe? We don't know yet.

On the opposite corner of Orion's hourglass figure is Rigel, the "foot" of the Great Hunter. It is the brightest star in Orion, and one of the brightest stars in the galaxy. To be over 775 light years away and still burn that brightly means Rigel is one energy-gushing star.

In fact, bluish-white Rigel is over 90 times bigger than our sun and pours out more than 50,000 times more energy.

From left to right, Alnitak, Alnilam, and Mintaka make up a triplet of other fiery, fast-burning stars, those that make up Orion's Belt.

They are about the same type and size of star as Rigel, telling astronomers that perhaps Rigel and the Belt Stars - and some of the other stars of the Hunter - were formed in the same super colossal stellar womb, the same cyclopean cloud of gas and dust, some ten million years ago.

We can see residual star formation still going on in the most famous nebula in the sky, the aptly named Orion Nebula.

Just below the Belt, and visible to the naked eye, is this cloudy-looking area of intense star birth. A decent telescope will bring out the four brightest stars in the heart of the nebula - the Trapezium. But the whole immense gas cloud is lit up from the energy of just one of those stars.

Theta1 C Orionis - yes, that's its real name - is that crybaby toddler star, the brightest of the four. It screams out so much nasty radiation, specifically ultraviolet, that it energizes the cloud to the point of lighting it up like a lightyears-across neon sign.

It has just millions of years left before it, too, detonates as a supernova.
The whole of Orion is an example of the fleeting nature of constellations. Often they are made of bright, massive stars that live fast and die young. Orion wasn't in the sky when dinosaurs ruled the earth. He won't be there in about 10 million years, by which time the major stars of the Great Hunter will have long since reached their expiration dates.

Like the Orion of mythology, this constellation is destined for a life cut short.

Enjoy it while you can.]]>ritter777@gmail.comNone2007-01-21T19:16:57-08:00http://www.firstlightastro.com/skiesabove/files/93b8dca19ab6e440982d0f769a3a8630-61.php#unique-entry-id-61http://www.firstlightastro.com/skiesabove/files/93b8dca19ab6e440982d0f769a3a8630-61.php#unique-entry-id-61After sunset tonight and for the next weeks to come, a solitary bright object in the western skies will be making a vain attempt to escape the clutches of the setting sun. It is Venus, the Evening Star, and her path in the sky over the next season will dramatically show us why she has been so popular through the ages in both myth and metaphor.

Venus has an orbit that is permanently parked in the Number 2 spot from the sun after Mercury. Her place in the sky, therefore, takes the bright planet never too far from the Sun from our perspective. If we could freeze the Sun in the noontime sky for a year we could watch Venus go around the sun - passing in front towards the right (the west), then crawling behind to the left (eastwards), coming out from behind to begin the circuit all over again.

Now you can imagine that during those weeks when Venus is to the west of the sun - on the "right" - she precedes the Sun when they both rise in the morning. It is then that our nearest neighbor is called the Morning Star, shining far brighter than any other object besides the Moon.

But months later, as Venus continues to orbit around to the backside of the Sun, she appears to be getting closer to our star every morning, and finally gets so close as to disappear into the fires the Sun.

Just weeks after that, Venus reappears on the other side of the sun, to the east, and follows that Greater Light through the sky.

Now, when the sun sets and the skies darken, Venus, the follower, has seemingly "reappeared" as the Evening Star. As her orbit takes her more and more around the sun, she appears to rise higher and higher in the twilight western sky. It's almost a "Look at me, see how bright and shiny I am!" sort of circumstance, an attitude that lends itself to great stories of human nature.

What Venus doesn’t know is that her current rise into brilliant fame is short-lived; she is destined for a fall back into the sun.

Venus's recurring ascent from and descent into the fires was well known by the Babylonians, and the Sumerians before them. In Babylon the goddess associated with Venus was known as Ishtar, in Sumer she was Inanna.

Inanna's stories are numerous, and can't be described here; not because of the space limitations, but because they were quite racy. She was one promiscuous goddess to say the least.

But one of her escapades, edited here for the family, shows us how nature and human nature unite in myth. E. C. Krupp's excellent book "Beyond the Blue Horizon" describes Inanna's exploits as she attempts to take control of the underworld.

Dressed to kill - literally - Inanna descends into the kingdom of the dead. Unknown to her, she is quickly discovered. Forced to disrobe, she is still unaware that she herself is being prepared for death. She finally stands naked before the magistrates of the netherworld, who find her guilty of attempted overthrow, and she is killed.

But some spirit spies are sent down into the abyss. They find her rotting body and bring her magically back to life. She then ascends again, reborn to former glory.

Sound like any planet we know?

The Bible itself uses the bright planet as a metaphor for the fall of prideful beings.

The prophet Isaiah condemns the king of Babylon in the fourteenth chapter:

How you have fallen from heaven, O morning star, son of the dawn.
You have been cast down to the earth, you who once laid low the nations!
You said in your heart, "I will ascend to heaven;
I will raise my throne above all the stars...
I will make myself like the Most High"
But you are brought down to the grave,
To the depths of the pit.

As you watch the great planet rise higher in the sunset skies over the next weeks, keep in mind the lessons given us from the ancients and painted on the skies: pride goes before the fall.]]>ritter777@gmail.comNone2007-02-04T19:13:48-08:00http://www.firstlightastro.com/skiesabove/files/5b5f455ba32ba4a4879553f76526a193-60.php#unique-entry-id-60http://www.firstlightastro.com/skiesabove/files/5b5f455ba32ba4a4879553f76526a193-60.php#unique-entry-id-60Today's quiz is brought to you by our home galaxy, the Milky Way. Now remember that the occasional friendly quizzes that we take here are just a fun way of educating ourselves about the universe. No need for clammy hands and palpitating heart. Sit back and have fun.

True of false: The Milky Way always looks the same in the night sky.

The Milky Way has been seen known since humans have walked this earth. It is that glimmering stretch in the nighttime sky so dense with stars it looks like a river of milk.

It turns out it is just the disk of stars, the galaxy we live in, seen edge-on; our stellar spiral of brightness filled with well over 100 billion stars.

But it doesn't always look the same throughout the year. During the summer, when our nighttime sky faces the center and most star-filled part of the disk, the Milky Way is at its brightest and most beautiful.

But our orbit around the sun means that six months later, during winter, our nighttime sky faces away from the dense part of the spiral out towards the less populated suburbs. The Milky Way then is not easily seen.

And the way it moves between these two extremes is rather counterintuitive. If we could see how it changes week to week, it would look like a giant hoop sweeping overhead, like a cosmic jump rope.

This means that during Fall and Spring, between the two extremes, the Milky Way is in a position which makes it appear to surround us on the horizon, essentially invisible to us.

True or false: Until recently the Milky Way was all there was in the universe.

In days of old when one looked up on the giant collection of stars overhead, it was reasonable to believe that the multitude of stars was all there was, that we lived in a star system and there was nothing beyond it. There were barely perceptible spiral clouds, "faint fuzzies" as an astronomer friend of mine calls them, believed to be local clouds of gas and dust or planetary systems.

Then along comes a man named Edwin Hubble. He sees the same faint spiral clouds above but thinks they are very distant galaxies, vast collections of stars hundreds of billion strong. To prove it he needs to find a special star called a Cepheid variable, a star that has an intrinsic brightness that astronomers can use to determine its distance.

Thankfully, the new telescope on Mount Wilson had just been completed. Through those giant eyes he found some Cepheids in the Andromeda Nebula. He was right; Andromeda was an entire galaxy unto itself, not part of our own. In one single discovery, the size of the universe exploded.

It turns out now that universe is unimaginably bigger than out galaxy. The Milky Way is only about 100,000 light years across. The visible universe extends probably more than 14 billion light years in all directions.

True or false: We don't know what most of the Milky Way is made of.

You'd think that in a day and age where knowledge flows like the mighty Amazon, that we would at least know what the Milky Way is made of. Well, embarrassingly enough, we don't. Here's why.

We know how objects should move about. For example, the planets move around the sun in such predictable ways that we can land spacecraft on planets within meters of where we want.

So it was thought that the stars moving around the galaxy should move predictably as well. Oh, that they would!

The stars out in the suburbs of the galaxy should move very slowly, like distant Pluto does around our sun. But in fact, and to the surprise of astronomers, they don't. They move way too fast - that is, too fast if all there is to the galaxy is what we see.

There must be something that makes up a lot of our galaxy - perhaps 95% of our galaxy! - which is made of matter, but matter we cannot see - a sort of dark matter.

What is it? No one knows yet. Stay tuned. For now, though, this statement is true.

Hope you did well! Until next time, clear skies!]]>ritter777@gmail.comNone2007-02-18T19:11:39-08:00http://www.firstlightastro.com/skiesabove/files/82cbe485d40f8fdd1dba78a0d24e6385-59.php#unique-entry-id-59http://www.firstlightastro.com/skiesabove/files/82cbe485d40f8fdd1dba78a0d24e6385-59.php#unique-entry-id-59One special night when I was a kid, back in the late sixties I hate to admit, I was in my backyard and spotted a bright object in the western skies, about halfway up from the horizon. That's one bright star, I thought, and figured there was no better time than now to break out my Sears 3-inch refractor telescope, with special solar filter adapter I'll have you know.

I set it up and picked what I was hoping would be a good eyepiece. I finally got that bright star centered in my finder scope, now confident it would be waiting for me in the eyepiece. I crammed my eye into that cheap .975-inch eyepiece, turned the focus knob, and...

And what I saw has stuck in my memory ever since.

It was no star in my eyepiece that night; it was a planet - a ringed planet. I had unwittingly discovered for myself the planet Saturn. I will never forget that event. It's been four decades since and still I am awed at the grandeur of that orb, even seen through an amateur backyard telescope.

You can now enjoy Saturn's beauty - you and your family - as it's now rising in the east right after the sun sets in the west.

We have just passed Saturn's "opposition," the point in our combined orbits when Saturn is opposite in the sky compared to our Sun, we are right between the two. This is a good time for us who like observing the Lord of the Rings seeing as it's as close and big as it's going to get this year. And it is fully lit.

Take your family out and with even a cheap department store scope (opt for a better one if one is available) find the great planet and take a look. Let it rise in the sky higher off the horizon to avoid the heat waves. See if you can see Saturn's faint golden color, or even the subtle east-west cloud patterns.

And of course admire the rings, those magnificent rings sweeping full around on both sides. A decent scope will be able to show you the Cassini division, a "gap" in the rings first discovered in 1675 by Giovanni Cassini.

Thankfully, Saturn is in a position in its orbit where, from our point of view, the rings are tilted up about 15 degrees. Some readers may remember back in 1995/96 when our view of Saturn's rings was edge-on. They had, for all intents and purposes, vanished. They are that thin.

Not this year, though! They are there in all their glory. Go and behold.

Come back a year from now and look at the exact same part of the sky and you'll notice something missing. That would be Saturn. Unlike the so-called "fixed" stars above - heavenly bodies that are there predictably, year after year - those wily planets move.

Saturn orbits around the sun in about 29 of our years. It's a pokey pace but that rate guarantees that by the time we catch up with it again next year it will have moved over to the west nearly 15 degrees, surrounded by a different menage of stars.

But there is no rush to see The Ringed One. It will continue to grace our sky until June-ish. Please, though, do try and get outside sometime between now and then and take a look at it. Take your kids, too. It may impact them the way it impacted me many moons ago.]]>ritter777@gmail.comNone2007-03-04T19:09:16-08:00http://www.firstlightastro.com/skiesabove/files/c348445af44557b669d42d811fe67fbc-58.php#unique-entry-id-58http://www.firstlightastro.com/skiesabove/files/c348445af44557b669d42d811fe67fbc-58.php#unique-entry-id-58Several weeks ago something new was spotted in the early morning skies in the constellation Scorpius, something which hundreds of years ago would have caused quite the uproar to say the least.

The new object, starlike in appearance, goes by the name V1280 Scorpii. By the time you read this it may have dimmed enough to require a telescope in order to be seen. But the point is: A new thing could be seen by the naked eye! The eternally unchanging skies changed for us, if only just for a couple weeks.

V1280 Scorpii is a nova, not to be confused with its more explosive sister, the supernova. But you can see in both names the root "nova," Latin for "new."
I'll explain what a nova is below, but it's interesting to note that just centuries ago actually seeing a new star appear in the sky was a paradigm shift of the first magnitude.

Back then the starry heavens were filled with the fixed stars, the never-changing canopy of lights arching over us from one horizon to another. For some they represented the sacrosanct realm of God where nothing varies. For many who lived during the time of Galileo or the famous astronomers Tycho Brahe and Johannes Kepler something new appearing in that hallowed sky was highly suspicious and went against the prevailing worldview.

But Tycho Brahe saw a new star, a "stella nova," in 1572 and using some simple math showed that it was not some atmospheric phenomenon, but something way, way, far away, where things were assumed to be fixed and unchanging.

He and Kepler and Galileo were part of a golden age of astronomy, when we started using events like novae and supernovae to see the glorious heavens as an extension of our physical universe and not some quintessential otherworldly firmament. The universe hasn't been the same since.

So what is a nova? Well, most of us are aware that a supernova is the explosive death of a big star. But a regular plain old "nova," sans the super - what's that?

Most stars end their lives with a whimper, with no explosive end. Our own star will give up the ghost that way. In ways beyond what I can discuss here, a star like the sun dies by shedding its outer layers, leaving behind only a white-hot core, christened a white dwarf.

Now that's pretty much the whole story if the star is all alone. But many of the stars up there are binaries, that is, they have buddy stars. That can make for quite a different scenario.

If the next door neighbor to a white dwarf grows up and out into what is called a red giant it is quite possible that the white dwarf may actually find itself stealing away some of its bloated friend's gas.

In stealing away the hydrogen from the other star, it now can form a new layer of hydrogen on its own surface. An old dead star is suddenly rejuvenated, if only temporarily.

Now understand that hydrogen is the fuel of stars, a stellar staple so to speak. The old dense, hot, white dwarf, previously depleted of fuel, now sees an opportunity to come alive again. The white dwarf's intense gravity crushes the hydrogen on its surface and heats it to about 40 million degrees Fahrenheit. This is enough to cause a fusion reaction (think nuclear weapons) and the surface erupts in a flash of energy.

The whole complicated process can last from weeks to months, and if the star is close enough to earth we can see a "new star," a nova, in the night sky.
If the white dwarf survives, this whole process may happen again, and again, and again, providing Earthlings with successive novae in following decades or centuries.

The nova may be a mere physical phenomenon, but it still inspires awe and wonder in the heavens, something the cold sciences will never take from us.]]>ritter777@gmail.comNone2007-03-18T19:06:43-07:00http://www.firstlightastro.com/skiesabove/files/4d3304be2023c80428206fec44011b6d-57.php#unique-entry-id-57http://www.firstlightastro.com/skiesabove/files/4d3304be2023c80428206fec44011b6d-57.php#unique-entry-id-57It doesn't take a great imagination to see that spring marks a sort of beginning or rebirth for so many people throughout the world, both ancient and modern. We proclaim it in our holidays, such as Easter and St Patrick's Day. It's also announced in nature in both the animal and plant world, as life seems to spring simultaneously from every corner of our land.

And, of course, our weather changes from the bleakness and wet of winter into a new kind of day, a more joyous climate, one that drives the celebration.

Not to take away from the poetry and romance of this beautiful season - on the contrary, we should all celebrate it - but much of what we enjoy about the season and find ourselves immersed in has a physical basis, one perfectly hardwired into the framework of our solar system.

The celestial cause of all this revelry is our planet's tilt with respect to the sun. Regular readers here will know that that is a truly wonderful thing about our home planet. For part of the year we are tilted toward the sun (summer), and part of the year away from it (winter). Between the two extremes we stand at upright attention to our star as we pass through the spring and autumnal equinoxes.

If we had no tilt, there would be no seasons; no bleak winter, no scorching summer, no windy, dry autumns, and of course no blooming spring. We would have essentially the same sort of weather all year long. The word "boring" immediately comes to mind. More importantly, though, the comfortable living places on this planet would be in narrow bands between a blazing equator and the permanently frozen northern and southern latitudes.

If we were tilted over much more, the seasons would be more extreme with summer always very, very hot, and the winters always frozen. Huge variations in temperature are not conducive to happy civilizations.

The way it is tilted now assures that there is the greatest amount of favorable weather spread out over most of the planet. Thus, our present tilt favors the greatest and most comfortable spread of civilization.

It is this Tuesday, at 5:09 PM to be precise, that we are at spring equinox - the planet is lit equally from pole to shining pole. For us in North America it is our passage from the "tilted away" days of winter to the "tilted towards" days of summer.

Of course this transition means more energy from the sun, which leads to warmer temperatures and more energy for the growth of plants, the bottom of the food chain.

We don't notice much of a change here in southern California with our minimal variation in weather, but in colder and wetter places - like back east - the first day of spring is a sign of hope: It will get better soon.

Now, of course, the weather doesn't change overnight - the birds don't start tweeting and bees don't start buzzing on the magical First Day of Spring. The climate always experiences a little delay. Just as our daytime temperature doesn't jump as soon the sun peeps its head above the horizon, the Earth takes a little while to warm as we approach summer. But it does happen.

You can probably see why many civilizations used to begin their new year in March. Remnants of those old days are still there in our calendar. With March as the first month, you can see that September was the seventh month (sept- meaning seven), with October (oct- = eighth), November (nov- = ninth) and December (dec- = tenth) following. January and February were the closing months of the year as the sun began to rise higher in the skies to announce that spring and a new year were coming.

With the coming of spring, with the hope of new life and rebirth, we can see how our lives as humans are once again influenced by some heavenly source.

Have a great spring!]]>ritter777@gmail.comNone2007-04-01T19:02:17-07:00http://www.firstlightastro.com/skiesabove/files/1d2e168271a0c0edfa9cfb98cffc00c5-56.php#unique-entry-id-56http://www.firstlightastro.com/skiesabove/files/1d2e168271a0c0edfa9cfb98cffc00c5-56.php#unique-entry-id-56You are undoubtedly aware that in this next week there are the celebrations of Passover and Easter. You may have noticed that they are not on the same dates as they were last year. Christmas, New Year’s, Independence Day - all the other big guys fall on the same dates year after year, but not these two.

You may also wonder why this phenomenon is being discussed in a column that deals primarily with the starry skies.

Well, these two days - high holidays for hundreds of millions of people throughout the world - set their dates on the movement of heavenly bodies, the sun and moon to be precise.

Passover is a celebration that goes back millennia, back to the days of Moses. The people of Israel were then slaves to the Egyptians, and God deemed it was the right time for Moses to get His people out of Dodge and into the Promised Land. Pharoah repeatedly balked at this divine decree and thus got himself in a heap of trouble, putting himself and his people on the receiving end of the now famous Ten Plagues.

The last plague had the Angel of Death taking the firstborn males of the Egyptians but “passing over” the houses of the Israelites, those that were marked with the blood of the lamb. The Jews were later to mark this memorable event, the beginning of the exodus, on their date of 15 Nisan. Now pay close attention, it can get a little complicated here.

Nisan is the 7th month of the Jewish calendar, a calendar that starts on 1 Tishri, better known as Rosh Hashana. That special New Year’s Day is defined as the first new moon after the autumn equinox. With me so far?

Now travel along with me 6 months down the road to the month of Nisan. That would be about 6 new moons later. At this point, add a couple weeks to get to 15 Nisan. That's Passover, which, being two weeks after a new moon, happens to be around a Full Moon.

Now just as Passover has its date determined by the sun and moon, so does Easter.

Easter, as we know, is the day Christians celebrate Jesus' resurrection from the dead. This is the highest of high holidays for them. Those who know the events of Jesus’ death know that he was in Jerusalem for the Passover when he was arrested and executed.

It is no coincidence that Passover and Easter fall so close to each other so often, with this year’s Easter just days after Passover.

The quick and dirty way to estimate which date Easter will fall on goes something like this: It's the first Sunday after the first Full Moon after the spring equinox. You math people will figure out quickly that the spring equinox is 6 months after the autumn equinox, and the first full moon after that is very often - surprise! - Passover.

And this year that first Sunday after the first full moon falls on April 8.

But it's not so easy as this every year. The Christian church uses a loose formula for setting equinoxes and full moons. It is not as exacting a science as astronomy.

For example, in 1962, astronomical and church renderings didn’t exactly agree. Then, the precise moment of the Full Moon took place a mere 6 hours after the exact moment of the spring equinox, both on 21 March. So Easter should have taken place the next Sunday, right?

Wrong. The Church’s less exact formula had the Full Moon on the 20th, followed by their 21 March equinox. So, according to the rules, the next Full Moon after "equinox" wasn’t for another month, and Easter wasn’t celebrated until 22 April! Something similar happens next year, too.

Is the occasional discrepancy a big deal in the Big Scheme of Things? Of course not. Easter will be celebrated and there will be much rejoicing regardless of the exact date.

But again, can you see how the uncomplicated and seemingly innocuous events happening in the cold cosmos above, the simple movements of the sun and moon, can affect millions of humans on this beautiful rock we call Home? I love this place!

Happy Holidays!]]>ritter777@gmail.comNone2007-04-15T18:58:19-07:00http://www.firstlightastro.com/skiesabove/files/e7cbfd258106b00949ded07d1b7b49f4-55.php#unique-entry-id-55http://www.firstlightastro.com/skiesabove/files/e7cbfd258106b00949ded07d1b7b49f4-55.php#unique-entry-id-55Sad but true: The many disciplines of science don't often get together to see a big picture. Science is like an inn with many rooms, but the guests very rarely get to know each other well. Astronomy is in one room, geology is next door. Biology is somewhere downstairs. It would be nice if they came together more often, over dinner maybe, to discuss their ideas and better formulate a big sweeping picture of the cosmos.


I was reminded of that predicament in a recent visit to the big island of Hawaii with my astronomy club. The island itself is a wonderful reminder that none of the disciplines of science is an island unto itself. They are all interrelated - from physics and astronomy to biology and anthropology - and would benefit in that awareness.

How can an island do that? It starts with Hawaii's creation.

Our planet, unlike any we know, has an outer layer of ultrathin movable solid plates crawling over a thicker layer of semi-solid molten rock. Where the plates meet or spread apart or move by each other we have volcanic activity and earthquakes.

But what about Hawaii? It is right in the middle of the Pacific Plate, nowhere near a boundary.

The big island of Hawaii rests on a "hot spot" on the plate, a point where magma below is extra hot. So much so that it burns a hole through the plate, oozes out, and breaks above the surface of the waters to form the islands.

We can see the history of the island chain as we go from Kauai in the northwest to the Big Island in the southeast. That hotspot is staying in the same place as the plate moves above. Thus Kauai, now away from the hot spot, is the older, more worn down, of the islands. Hawaii is the youngest. In fact, Hawaii is still growing, spewing lava into new real estate near the Kilauea volcano.

But that's the not the whole island story. The physics of weathering on this planet form and shape the island into a paradise. The waves constantly pound the coastline breaking up the lava and coral reefs into beaches. The amazing water cycle on planet Earth provides a constant rain there that helps to slowly break down the volcanoes, shaping beautiful valleys in the process.

But there is more than the physical sciences at work here. Life plays a role in the shaping of paradise. Plant roots break up the hard rock which, together with dead plant material, make a profoundly viable soil, so fertile you'd think anything could grow on it.

All this makes it easy for insects and other animals to eventually carve out ecological niches for themselves. Wonderfully coordinated ecosystems fill the island.

Finally, after years of preparation, the island is primed and ready for discovery by ancient peoples sailing from other islands hundreds and hundreds of miles away. They arrive, now ready to call this island, and the others in the chain, their home. The whole process is not unlike the whole history of our own planet - in miniature.

Modern discoverers attracted to the Big Island now build the best observatories in the world on the top of its highest mountain, Mauna Kea, where the skies above are impeccably clear and free of human light pollution, a contamination that ruins the skies elsewhere. And it is here that some of the most amazing discoveries about our universe are made today, discoveries that help us to understand better the workings of the cosmos and our place in it, including the rich history of the Hawaiian Islands.

But aren't these coordinated processes taking place all over the planet, processes which mold and fine-tune this planet to near perfection? Sure they are. The Big Island just focuses it all into an intense beam of discovery and appreciation.

If you have an interest in any of the sciences and you have the opportunity to go to the island of Hawaii, do. From the active volcanoes in the south through the rainforest jungles and falls in the east to the arid snow-capped observatory-studded summit of Mauna Kea, the Big Island helps us to understand and appreciate the Big Picture of it all.]]>ritter777@gmail.comNone2009-05-04T18:51:53-07:00http://www.firstlightastro.com/skiesabove/files/28f18734eaae0dffeb0c746695bc9277-54.php#unique-entry-id-54http://www.firstlightastro.com/skiesabove/files/28f18734eaae0dffeb0c746695bc9277-54.php#unique-entry-id-54That dreaded time of the school year is upon us; the time that fills teachers and administrators with angst and causes untold numbers of children to roll their eyes to the sky while sighing, "Do we have to?" The state tests are here again.

Let's try and counter the unease many of us feel and take a fun and stressless quiz of our own. Only three questions and it's not even graded. And there is a bonus! You will be more learned because of it. Ready? Grab your sharpened Number 2 and let's do it.

Question 1: We live in a huge collection of billions of stars. What is it called?

A) The Milky Way
B) The Solar System
C) The Orion Nebula
D) Hollywood, CA

Regular readers here will nail this one instantly. It is the Milky Way, of course. Our galaxy, well over a hundred billion stars strong but organized nicely into a barred spiral shape, is our home.

The solar system is, of course, our local group of planets and debris orbiting the sun. And the Orion Nebula is that star nursery about 1200 light years away in the constellation Orion.

Question 2: What is the origin of our atmosphere's oxygen?

A) Asteroid and comet bombardment
B) Eons of plant life
C) The decomposition of ocean water
D) Walmart

This one isn't so easy but it is keenly important. Bombardment gave us extra rock material to be sure, and is probably responsible for a lot of our water, but not for any significant amount of oxygen. And water itself can break up into hydrogen and oxygen but is definitely not the source of our life-preserving amount of oxygen.

Plant life is the culprit. Early on this planet had essentially no free oxygen. The plants through photosynthesis slowly - and I mean slowly - immersed our planet in the gas. Much was taken by the rocks and oceans but some of it was eventually pumped into the atmosphere, perfectly timed for the arrival of the more complex animal life on land. A miraculous bonus was that some of this oxygen got converted to ozone to protect us from the nasty UV rays from the sun.

Question 3: Why is the liquid magma below us still so hot?

A) Radioactivity
B) The sun warms it.
C) Our magnetic field adds heat to the core.
D) Someone left the iron on.

After 4.5 billion years our insides are still hot as where the devil lives. Why? The big reason is that radioactivity from unstable elements keeps it real hot and the crust traps that heat. Result? We have a molten inside upon which our crust floats. The upshot is that we still have plate tectonics after all these years. Go Earth!

Do well? Of course you did! Until next time, clear skies!]]>ritter777@gmail.comNone2007-04-29T13:00:39-07:00http://www.firstlightastro.com/skiesabove/files/9445fb218e50990ace3b4443ddb83c46-53.php#unique-entry-id-53http://www.firstlightastro.com/skiesabove/files/9445fb218e50990ace3b4443ddb83c46-53.php#unique-entry-id-53Turn the month of May into a planet watching extravaganza! OK, maybe I'm a little too excited about this, but for those readers who for the first time in their lives are taking an interest in the skies and enjoy watching them change before their eyes, the merry month of May is like Planetary Movements 101.

Only half of the planets are seriously contending for your attention, but they make the most of their other-worldly personalities.
Mercury and Venus and Saturn will be vying for your interest in the western skies after sunset. Jupiter will strut down the cosmic catwalk later on in the southeastern skies.

Alas, mighty Jupiter doesn't rise until about 11 P.M. at the beginning of the month. But as we catch up with it in our orbit it will rise earlier and earlier. By the end of the month, the great king will rise around 9 P.M. You cannot mistake it; it is by far the brightest object in the southeast at those hours.

Even though he shines very brightly, being down so low to the warm horizon ruins attempts to see the fine details of the Giant of the solar system. Summer will be a better time to see Jupiter; it will be rising earlier and soaring higher at more reasonable hours.

This is a great month to see Saturn especially if you have a telescope to help discern those beautiful rings. The Ringed One is high up in the southern skies at the beginning of May, but seems to slowly creep up on Venus in the west as the month wears on. Our orbit will soon take us to the other side of the sun as Saturn, and the Belted Beauty will bow out of the Planet Play, behind our star, but only for a while.

If you've been one of the followers of Venus you will have already noticed that the brilliant jewel of the western skies keeps rising ever so slowly above the horizon. It has been running around the sun, trying to lap us in its orbit. It soon will, and as it does it gets brighter and brighter as it comes nearer and nearer to us. Being covered in clouds that reflect about 60% of the sun's light makes it one really dazzlingly bright planet.

As it gets nearer, it is also easier to see details through a telescope. At the beginning of the month, see how she is like a miniature gibbous moon. As she closes in she will look more and more like a first quarter moon, with half of the planet clothed in darkness. Please mark May 19 on your calendar! It is on that evening that the crescent moon and Venus nearly kiss. It will be awe-inspiring, a great evening to write a poem.

These phases of Venus were first seen by Galileo and proved - to him anyways - that Venus was orbiting the sun and not us, an idea which centuries ago was a revolutionary paradigm shift. It took decades after his discovery for that new idea to be generally accepted.

Venus will peak during the month, almost seeming to hover there in position. In June it will begin to slowly sink towards the horizon as it passes between the sun and us.

Mercury is at the moment rounding the sun on the far side. And, true to form, the mercurial little one will leap up into the western skies around mid-month, seemingly out of nowhere.

By the end of the month it will have already reached its peak in the heavens after sunset, just about a handspan above the horizon, only to quickly disappear during June.

You'll notice that both Jupiter and Saturn hardly move at all through the skies during their May appearance. They are part of the very distant outer planet group, all very slow moving, in no hurry to get anywhere. They will be in basically the same area of the sky the next time we swing around.

Venus and Mercury are inferior planets - no offense - and thus are always hugging the sun. Because of the laws of planetary motion this close couple are always in a hurry. One can actually observe their movement through the stars week by week, they travel that fast.

Why don't you? Take time this month and go out and do a little planet watching.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-05-13T12:56:43-07:00http://www.firstlightastro.com/skiesabove/files/81f7372484a9ad130129a6207d6fc1ac-52.php#unique-entry-id-52http://www.firstlightastro.com/skiesabove/files/81f7372484a9ad130129a6207d6fc1ac-52.php#unique-entry-id-52If you could give away one galaxy in our universe to as many people as you could, how many people would receive one before you ran out? Thousands of people? Hundreds of thousands?

It turns out that everybody on this entire planet could have his or her own galaxy. Wait! Make that many galaxies. Amazingly, there are enough galaxies out there that every man, woman, and child on planet Earth could call more than 20 galaxies their own. There are at least 100 billion of them out there, each with tens to hundreds of billions of stars.

Needless to say, the universe is big and chock-full of galaxies.

We have an idea of how big the visible universe is and approximately how many galaxies are out there, but no one can really comprehend the enormity of it all.

So at the risk of drowning you - and myself - in the vastness of space, let's just talk today about how galaxies are arranged and why the location of our own galaxy, the Milky Way, is so critical to life on Earth.

At the very beginning, over 13 billion years ago, just after the creation of the universe, what "stuff" there was in those early days began to clump under the influence of its own gravity.

Now back then there was nothing much more than hydrogen and helium, as far as the "normal" stuff goes. The other stuff would include dark matter, but that's for another day.

This hydrogen and helium could clump together to form the first stars. Those first fields of stars would be like wannabe galaxies, things we might describe as misshapen starry blotches in the cosmos.

Through mechanisms still not well understood, these first mini-collections of stars could attract each other into enormous collections of stars - the first recognizable galaxies.

All this clumping and coming together meant that a lot of the universe became uninhabited, that is, vast voids opened up between those clumps. The universe would start to look like a map of our country – far-reaching stretches of emptiness lined through with roads of small burgs and large metropolises.

Some of those monstrous galaxy factories could churn out 1000's of galaxies in a particular area of the universe, a collection we humans would later call galaxy “clusters.”

We ourselves belong to a huge cluster of clusters called - to no one's surprise - the Local Supercluster.

Now this would be nothing much more than some interesting space trivia, except for the fact that our place in this supercluster is supercritical to life on this planet. Why?

We do not want to be in the middle of those clusters, believe me. Those seemingly innocent galaxies are not just sitting around doing nothing. They are close. They are interacting. They are gravitationally attracted to each other. They are tearing each other apart.

But aren’t they really far, far away from each other? Not really.

The average distance between the stars within those galaxies is enormous, to be sure. If an average star were the size of a grapefruit, the next nearest grapefruit star would be on the other side of our country. There is puh-lenty of space between them.
But if the average galaxy were grapefruit-sized, the next nearest grapefruit galaxy would just be tens of feet away. That’s very close and leads to a lot of intergalactic harassment.

We should be thankful that the Milky Way galaxy, our home, is sitting out here in the distant suburbs of our cluster. Here we are practically alone. Here we can retain our incredibly critical spiral shape. There are no other nearby biggies that will rip us up into galactic shreds. And life on this little planet can flourish.

Again, even when we aren’t looking for it, we inevitably find another way our planet is perfect for life. Earth is placed perfectly in a perfect type of galaxy in a perfect location on the outskirts of a perfect cluster. What a wonderful world!

Until next time, clear skies!]]>ritter777@gmail.comNone2007-05-27T12:50:47-07:00http://www.firstlightastro.com/skiesabove/files/8e53298e75fb1c677d4a4a318eb99729-51.php#unique-entry-id-51http://www.firstlightastro.com/skiesabove/files/8e53298e75fb1c677d4a4a318eb99729-51.php#unique-entry-id-51Just a couple Saturdays ago, on the 19th, you may have witnessed the sublime site of Venus nearly touching a young crescent Moon in the western skies after sunset.

It was a gem of an experience. But if you went out the next evening to see it again, you may have noticed that things were not exactly the same, that the Moon was actually a little higher in the sky and had a slightly fuller crescent.

What's all this then? What you experienced is the movement of the Moon around our planet, movement that gives us those phases.

We are all familiar with the Crescent Moon and Full Moon and Quarter Moon (often called Half Moon). But few of us actually sit down and wonder why these things are.

We all learned in grade school that the Moon goes around the Earth. Many of us mistake its movement through the night sky, side by side with the stars, as the Moon orbiting around the Earth. But that movement is an illusion; it's just our planet spinning below the sky, the same fata morgana that "moves" the stars and the sun through the heavens.

The Moon really moves the other way, from west to east. But it moves slowly, very slowly, taking a whole month to complete one circuit. Test it! Go out tonight and notice exactly where the Moon is at a certain time. Go out tomorrow night at the same time and see that it has moved about a handspan eastward.

Now this journey is why we have all those phases of the Moon. Here's how. Imagine the Moon in the part of the sky right near the Sun. The lit side of course is facing the Sun, its dark side is facing us. We cannot see the moon because of this. We call it New Moon because a new cycle has begun.

Now let's fast forward two weeks, halfway through its cycle when the moon is on the opposite side of the sky, opposite the sun. Now it is fully lit from our point of view. It is a Full Moon.

The phases we are accustomed to result in the lighting of the Moon as it goes from New to Full and back again.

For example: In the next days after New, as the Moon passes by the Sun, it is at such an angle from us that we can just begin to see its lit side, but just barely. That is the crescent Moon, a thin one to be sure.

As the Moon moves around us it appears to be getting more fully lit. It is "growing" or, as we say, waxing.

After a week of a waxing crescent, it is now half lit from our point of view and directly above at sunset. Some call this half Moon. It is a quarter of the way around us, so astronomers call it First Quarter Moon.

It has lost now its crescent look. For the next week, until Full Moon, it will appear more football-like. This is called a gibbous Moon - a waxing gibbous to be more exact.

The Moon will continue to "fill out" as it goes to the other side of the Earth.

Once it is full, growing time is over. Now it is swinging around back towards the sun again, and its lighted part will appear to be getting smaller - it is now a waning moon.

After two weeks of waning from Full to Gibbous to Third Quarter to Crescent, the Moon will begin the cycle all over again.

Did you notice that during the full circuit that the lit part was facing the setting sun as it was waxing, and that it faced the soon-to-be-rising sun as it was waning?

None of these facts were lost to, well, probably every people group that has gone before us. Knowing the Moon and its phases was a great timekeeper and calendar source for a thousand generations of people.

Maybe for you, too! With just a little practice you can start predicting when what phases will be present. After a while you can put that watch away, you'll be able to estimate the time of the night just by looking at the Moon, just like our ancestors did.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-06-10T12:47:16-07:00http://www.firstlightastro.com/skiesabove/files/be564e42c4c11ac94ec819a4723c3502-50.php#unique-entry-id-50http://www.firstlightastro.com/skiesabove/files/be564e42c4c11ac94ec819a4723c3502-50.php#unique-entry-id-50The end of the year for teachers and students doesn't really happen in December; it occurs in the merry month of June. In keeping with the scholastic spirit of the season, let's take a short final exam on some of what we've learned here in this column for the last 10 months. Ready?

1. The sky is blue because: a) it reflects the oceans, b) molecules in the atmosphere bounce the blue photons from the sun all over the sky, c) the sky has water in it.

Well, the sky does have water in it, but you can't see it unless it bunches up together into those puffy things we call clouds. And no, the ocean is not reflected in the sky. But the tiny gas molecules in the air do cause the bluer photons from the sun to bounce about in erratic paths giving us the impression the whole place is lit up in blues. Answer: b

2. The summer Milky Way is bigger and brighter than the winter Milky Way because: a) in the summer we face the star-studded center of the galaxy, b) the sun is out longer making the night sky brighter, c) the summer planets just make it appear that way.

There are no "summer planets," so that one is out straightaway. And the sun itself plays no role in a nighttime sky. But our night sky during summer does face toward the billions of stars in the galactic center. During the winter we face the dreary and not-as-well-populated outskirts of the galaxy. Answer: a

3. Which of the following wavelengths of light do we use in astronomy? a) Just the ones we can see, b) Just the sun's wavelengths, c) Gamma rays, d) All wavelengths we can get our curious little hands on.

In the old days, up until the last century, all we could use were the very limited "visible" wavelengths of light, the colors of the rainbow. Now we have telescopes that can tune into just about any wavelength; from long radio waves, through the infrared, ultraviolet, and x-rays, over to the ultra-small and ultra-dangerous gamma rays. And with that, in the last century we have "seen" more of the universe - visible and invisible - than any generation before us in the history of humankind. Answer: d

4. How many stars are responsible for illuminating the Great Nebula in Orion? a) Just one, b) Billions and billions, c) What's this Great Nebula thing?

Seeing images of Orion's great cloud on sites such as Astronomy Picture of the Day, there just has to be an army of stars lighting the whole place up. Alas, no. It is just one hyperactive whiney star in the center that is responsible for providing the energy necessary to ionize the entire region. Answer: a

5. Venus is always seen in the sky: a) on the opposite side as the sun, b) near the sun, c) nobody really know where she will pop up next, that crazy vixen!

Thanks to Newtonian mechanics we know exactly where Venus will be tomorrow - and 100 years from today. And because she is on an inside lane around our star, she will always be in the same vicinity as that great ball of gas, and never on the opposite side of the sky. Answer: b

6. Easter and Passover set their dates by: a) the phases of the moon, b) the phases of the sun, c) the spin of a dreidel.

Well, the sun has no phases. And of course there are no dreidels involved in choosing the dates for high holidays. Both Easter and Passover are dependent on the phases of the moon, specifically the first Full Moon after spring equinox. Answer: a

How did you do? If you are a regular reader here, I'll bet you did well. You can always go back and read the full explanations in our archives of The Skies Above at firstlightastro.com/skiesabove.

Until next time: a) clear skies, b) go learn more about the universe, c) tell others about the wonders of our sweet Home, d) all the above. Answer: d]]>ritter777@gmail.comNone2007-06-24T12:44:49-07:00http://www.firstlightastro.com/skiesabove/files/6adccf95e3373646a28c3df04835989f-49.php#unique-entry-id-49http://www.firstlightastro.com/skiesabove/files/6adccf95e3373646a28c3df04835989f-49.php#unique-entry-id-49You are sitting in your backyard after sunset watching the evening sky begin its fade to black. Even before the sun fully sets you notice a small bright light gradually appearing in the west. Of course that's Venus. As the sky darkens a gleaming spot in the southwestern skies seems to brighten, as well. That would be Jupiter. Then slowly over the next half hour or so, stars seem to just show up from out of nowhere.

If you are away from the city lights and the Moon is not out at the moment, the sky will seem to fill with stars over the next hours.

If you didn't before, you now get an idea of how varied the brightness of stars can be: from celestial bodies so bright you can see them just as the sun sets, to stars so dim you can only see them after the sky goes pitch and your eyes have adapted for the darkness.

Of course the brighter stars have always played a major role in the construction of constellations, and in the mythologies and oral traditions of many people groups. But it wasn't until just a couple thousand years ago that some people tried to take a more scientific look at all stars, bright to dim.

Over two millennia ago, Hipparchus, one of the great astronomers of the ancient days, categorized the stars into a brightness scale. The brightest stars in the sky were classified magnitude 1. The dimmest, nearly imperceptible stars were magnitude 6. All the rest of the stars fell somewhere in between.

We still use basically the same scale today, but not without some ado.

For example, what is disturbing for modern minds is that the brightest stars up there have the lowest magnitudes. So a star of magnitude 5 is considerably dimmer than a magnitude 2. That's not a big problem, but being counterintuitive it can be a little annoying.

More exasperating, though, is what happened as our knowledge of the skies grew.

What about objects in the sky that were brighter than the brightest stars - like Venus? What magnitude should they be assigned? Well, inconveniently astronomers agreed to take those brighter objects down to zero and then lower, into the negative numbers! So, for example, Venus, the brightest object in the sky besides the sun and moon, has a magnitude of -4.4!

But why stop there? The Moon, when full, has a magnitude of less than -12. And the brightest star in the sky, the sun, is magnitude -27! Yikes!

When telescopes were invented and could open their bigger and more sensitive eyes to the heavens, they could pick up light from objects our tiny eyes could never see. The scope was like a battering ram that broke open the door on the other side of Hipparchus' scale. With their help we can now see objects with magnitudes near 30! To give you an idea of how dim that is, the Hubble Space Telescope had to keep its shutter open for more than a day just to pick up enough light from those distant objects to get an image!

This whole crazy magnitude scale, like that embarrassing uncle at family gatherings, is here to stay, but once you get used to it, it isn't that bad.

Sadly, today, because of light pollution we are losing the higher magnitude stars to the bright lights of malls and casinos. For those living near cities today, it is a good night if one can see down to magnitude 3 stars. To the disappointment of many, the starry hosts of yesteryear are becoming the starry handful for today's generation.

Until next time, clear skies - and dark nights!]]>ritter777@gmail.comNone2007-07-08T12:40:50-07:00http://www.firstlightastro.com/skiesabove/files/3160a792c86325fbbd17c117b652e761-48.php#unique-entry-id-48http://www.firstlightastro.com/skiesabove/files/3160a792c86325fbbd17c117b652e761-48.php#unique-entry-id-48Some of the most common words and phrases we use are based on phenomena in the skies above. All the days of the week, some months and seasons, even the names of some geographic features of our globe, can find their origins in the heavens.

And our common terms of telling time, specifically the ubiquitous AM and PM, are also based on the movements of the sun above our heads.

For most of us, AM and PM are quick and simple ways of indicating morning and afternoon or evening. But it goes a little deeper than that. Ready?

AM stands for ante meridiem, Latin for "before the middle of the day." PM is for post meridiem, "after the middle of the day."
So far, so good. Before noon, after noon - no big deal. But what exactly is the middle of the day? And is my middle of the day the same as yours? If not, how does that change things?

It takes no great strain of the imagination to see the middle of the day as the time when the sun is highest in the sky, essentially dead between sunrise and sunset. But let's be more precise.

Imagine splitting the sky with a line from true north all the way over your head down to true south. We could call it the meridian, the midday line, and that's what astronomers call it. It is the border between AM and PM. Before the sun gets there, before the meridian, we have AM. When the sun gets there, we have midday or "local noon." Afterwards, it is PM. But, as we'll see, this noon is not the noon we are accustomed to.

This whole midday line and how the sun moves through it is one of the foundations for the old sundial way of timekeeping. But the old observational ways of telling time pose a great problem in the modern world, because - cue dramatic music - not everyone's meridian is the same!

It is easy to see that when the sun reaches midway in an Arizona sky, it still has a ways to go before it reaches midway in a California sky. More dramatically, the sun at the meridian in San Diego still has 5 minutes of sky-crossing before it reaches meridian in Los Angeles. Bottom line: Go east or west and your time changes.

Imagine living back 150 years when timekeeping was indeed important, but pretty much only at the local level. You live in a village or city, and most of your life was spent doing business there. You set your watch or clock by the local noon, a time determined by the sun in your own local sky. All is well.

But then the train is introduced to modern civilization and suddenly great distances are covered in short order. Now you go a hundred miles to the east or to the west in a day and the sun isn't exactly moving with your watch. Because of this, you must constantly reset your timepiece to match the local time.

Some clever people at the end of the 19th century saw a big mess coming as more people traveled, and came up with the idea of time zones, huge areas locked into a certain time regardless of when the sun was crossing the local meridian.

Of course this move saved a lot of time adjusting timepieces, and meant people in different cities could synchronize when to meet or call or plot. But it also meant that noon was no longer true noon, AM and PM had lost their original meanings, and sundials went the way of the dodo. Scheduling a duel at "high noon" was a thing of the past.

Again we see that the great lights in the heavens, especially that bright one that rules the day, has far-reaching effects in nearly every facet of our lives together down here, even if the effect is slightly modified by man. Timekeeping, temperature, climate, weather, ocean currents, seasons, a host of astronomical influences, and of course life itself can find a common starry thread in the sun.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-07-22T12:38:10-07:00http://www.firstlightastro.com/skiesabove/files/3216dd56a2ae433ce0c7d339b8d18b5b-47.php#unique-entry-id-47http://www.firstlightastro.com/skiesabove/files/3216dd56a2ae433ce0c7d339b8d18b5b-47.php#unique-entry-id-47The skies above are filled with stars whose patterns try - successfully - to force our minds to see common geometric shapes in them. There is the quadrangle outlining Orion, the trapezoid trapped in Hercules, the Great Square of Pegasus, the semicircle of the Corona Borealis, and that dipper-looking thing in... well, the Big Dipper.

During the summer, above our heads throughout the night, is a triplet of stars that plots out a very nice triangle. It is called, to no one's surprise, the Summer Triangle.

It is made of the stars Vega, the brightest of the three, Deneb, the northernmost, and Altair.

In this week's column and for the next two consecutive, we will spend our time getting to know these three a little better - by looking at the constellations they call their home, their mythical pasts, and what they mean to us in the sciences.

Let's start with Vega, the brightest star overhead in the evening and the fifth brightest star in all the sky. It is part of the constellation Lyra, a tiny but story-filled collection of stars.

Lyra's story comes to us westerners from a story involving the likes of the mythological Mercury, Orpheus, and Eurydice. In short, it goes like this.

Once upon a time, Mercury fashioned a really nice harp out of some strings and a nice shell he found on the banks of the Nile.
Apparently it made one sweet sound, so sweet that Apollo traded Mercury his wing-tipped, snake-entangled, power-filled staff for it.

Sweet deal!

Eventually Apollo passed on this lyre to his son Orpheus, who used it to get his dead wife, Eurydice, back from Pluto, King of the Dead, after Eurydice had a fatal accident.

Orpheus played the lyre so well that Pluto told him to go ahead and take Eurydice back home to the living, but with this restriction: He may not look back to the Death Realm on his way out.

Surprise! Orpheus glanced back at the last moment and - alas! - Eurydice slipped back into Hades. No amount of strumming on his fancy instrument changed Pluto's mind.

Orpheus, still a prize to women who were enchanted by the sweet sounds of the lyre, was in such despair that he shunned his many wooers. Eventually the rejected women murdered Orpheus, and tossed said lyre in the river.

Jupiter, witnessing the whole thing but apparently more concerned about the lyre than Orpheus, commanded that the lyre be taken from the river and placed into the sky. It can be seen tonight in the exact spot where Jupiter had it placed.

Vega, the brightest of stars of our tiny celestial lyre, is a blue star a mere 25 light years away. It is only about 3 times bigger than our sun, but because of the laws of stellar burning, pours out 60 times more energy than our star. It, like so many other stars, is best seen at a great distance. Trust me.

But because of its great size, it is burning its fuel quickly and will live just a fraction of the time our sun will, maybe a mere billion years total. It's probably at midlife now.

One interesting fact about that bright starry beauty is that it used to be our Pole Star, and will be again. Right now, Polaris, the North Star, sits in that coveted spot. It is directly over our planet's spin axis, specifically the North Pole - so all the stars appear to spin around Polaris.

But our planet, like a spinning top, slowly wobbles over time - very slowly. Because it wobbles, or precesses, the star directly above our planet's axis changes over time. About 14,000 years ago, Vega was overhead, a fact alluded to in ancient Akkadian and Sumerian texts. But if you missed it the first time, don't worry! Vega will again be our pole star, when we spin back around to it in about 12,000 years.

In our next installment we'll hop over the Milky Way to another point of the Summer Triagle - Altair.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-08-05T12:36:12-07:00http://www.firstlightastro.com/skiesabove/files/9f84018d423d495fcb376e747e56f7b3-46.php#unique-entry-id-46http://www.firstlightastro.com/skiesabove/files/9f84018d423d495fcb376e747e56f7b3-46.php#unique-entry-id-46To most humans throughout history the stars have been more than mere points of light. We connect the dots and see the obvious shapes and figures, and if we look deeper, with our mind's eye, we see stories all over. It's the way we were designed, to see beyond the obvious - if we choose to look.

In our last time together we looked at some stories surrounding Vega, the great blue star directly above our heads in the evening, and one point in our Summer Triangle. Today we look closer at our second featured star in this trilogy, the star Altair in the constellation Aquila.

The bright star located to the south and east of Vega, just across the Milky Way, Altair together with Vega played a primary role in an ancient Chinese myth.

There are variations of this story, to be sure, but basically it goes like this. The Sun Emperor has a daughter, Tchi-niu, an expert weaver. Reliable sources say she could weave some amazingly colorful sunrises and sunsets.

But she is lonely, which in the old stories means romance is soon to follow. Sure enough, Tchi-nui looks out the window one day toward the river that we call the Milky Way and her eyes meet those of the herdsman, Kien-nou. Fireworks go off and they are in love.

The herdsman is very good at his job and so the Emperor has no problem with his daughter marrying this fine, young Kien-nou.

Things go well for a while, but soon the two begin neglecting their duties. Tchi-niu is not weaving her sunsets with the usual rich colors and Kien-nou's cows are wandering all over the place. What to do!

The Emperor is not pleased. After repeatedly telling them to get their proverbial act together, he finally banishes his heedless herdsman son-in-law to the other side of the Milky Way.

The star-crossed lovers cannot convince dad to change his mind. The now crestfallen Tchi-niu, try as she may, just cannot overcome her grief enough to weave out a nice sunset. The Emperor has to do something!

So he summons all the magpies in China to spread their wings into a bridge once a year, on the seventh day of the seventh month, across the Milky Way, so the couple can spend one day together.

We still see the two in the skies during the summer months, with Vega in the role of the weaver princess, and Altair as the herdsman. Sadly, our modern civilization with all its light pollution has all but dried up the Milky Way. Weaving any myth today about the two would require no magpie bridge; there is barely a river to cross.

To cold science, Altair is a type A star. That means it is about twice the size of our sun, with a surface temperature about 2000 kelvins hotter than our sun. It pours out more than ten times the amount of energy than our own star does. Again, not to beat the dead star, but Altair is another big, nasty star best kept at a distance.

Which is actually its standout characteristic. Altair is a mere 17 light years away, almost 100 trillion miles away. That, believe it or not, is very, very close as star distances go, just at the end of the block.

Altair is part of the great constellation Aquila, the Eagle. In our next time together we fly over to another great bird in the sky, Cygnus the Swan. Nested there is our third and last of the Summer Triangle, its northernmost star, Deneb.

Until then, clear skies!]]>ritter777@gmail.comNone2007-08-19T12:34:01-07:00http://www.firstlightastro.com/skiesabove/files/042bfeff7df549e4438d3574450fd92b-45.php#unique-entry-id-45http://www.firstlightastro.com/skiesabove/files/042bfeff7df549e4438d3574450fd92b-45.php#unique-entry-id-45This is the last of our trilogy on the starry points of the Summer Triangle. Our first two visits took us to bright blue Vega and her companion across the Milky Way, Altair. Now we will sail upstream, along the Milky Way to Deneb, the main star in the constellation Cygnus the Swan, and the northernmost of our triad.

Cygnus is also known as the Northern Cross. (You'll never guess why.) But not only does our constellation look like a cross, it also, surprisingly, looks like a swan! Remember, not many constellations actually look like their namesake; Cygnus is an exception.

If you go out tonight you can see the cross overhead, with the top of the cross in the north, the foot of the cross more southerly and almost overhead. One can imagine the pole of the cross as the swan's body, with is tail on the north end, and head at the south. The two perpendicular stars are its outspread wings.

There are several stories that accompany the Swan. But one is a story that remains fresh especially in today's culture with our fair share of wild youth.

Helios, the sun god, had an ungodly son named Phaethon. As is the nature of many young sons, he decided to take his dad's Sun Chariot for a spin one day. Big mistake. Phaethon was not the best driver and apparently had little respect for the houses of the gods and their peaceful existence above. His hellish driving put the heavenly hosts in immortal danger.

Jupiter was not amused. He finally decided he had had just about enough of this young whippersnapper, and chucked him from the chariot. Thrown to earth in a flash, Phaeton fell fatally into the river Eridanus. Enter Cycnus.

Cycnus was a friend of Phaeton. Devastated by the turn of events that resulted in his friend's death, he felt it his duty to collect every body part of his charred, dismembered friend for a proper burial. He made several arduous dives into the Eridanus to gather all his remains.

Seeing all this devotion, Jupiter and his minions were moved. So Jupiter decided to reward Cycnus for his act of selflessness, although the reward by today's standards may not be a welcome one.

Jupiter thought it would be nice to turn Cycnus into a waterfowl! And since he ruled the heavens there was no discussion about it. Behold! Cycnus metamorphosed into a swan. And his name was now Cygnus. And, as an added bonus, he was placed into the starry dome above where we see him still today.

Let's focus now on our star of the week, Deneb, the brightest star in Cygnus. Deneb is the top of the cross, the tail of the swan. Its name, like so many other stars, is from the Arabic. Al Dhanab al Dajajah is its full name, which means "the hen's tail."

Deneb is one of the brightest stars in the summer sky, but it is also very, very far away. Vega and Altair are just tens of light years away, Deneb is over 3000 light years beyond that!

What does this tell us? For Deneb to shine that brightly at that great distance makes him a monster big star. How big? Our best estimates put him at over 250 times the size of our sun!

Deneb may have a claim as Cygnus' brightest, and it may be one member of our very elite Summer Triangle club, but for a beautiful sight through the telescope, and a favorite at star parties, go to the foot of the cross. There, like two brilliant starry diamonds are Albireo, a double-star system containing a striking blue star and its reddish companion.

In fact, take a telescope and, using the Summer Triangle as a reference, scan the skies in the region and farther south down the Milky Way. You will find nebulae and double stars and what seems like sparkling dust, which is the star-studded Milky Way itself. It is an awesome trip. But don't scan too quickly, Jupiter might object and we know what happens to those who race through the Milky Way!

Until next time, clears skies.]]>ritter777@gmail.comNone2007-09-02T12:30:11-07:00http://www.firstlightastro.com/skiesabove/files/5cda260d8776e38e153112c9f36054a5-44.php#unique-entry-id-44http://www.firstlightastro.com/skiesabove/files/5cda260d8776e38e153112c9f36054a5-44.php#unique-entry-id-44Do you enjoy watching a cast of real-life eccentric characters drowning in high drama, a drama that spans decades of history, and all of which makes up a fascinating part of our American heritage? Then you may be in for a treat with a film being shown at this year's Temecula Valley's International Film and Music Festival - The Journey to Palomar.

Many of us are at least aware of the Great Observatory on Palomar Mountain. We've seen its image on water bottles among other places, and those of us who drive south on the 15 through Murrieta and Temecula can see the magnificent dome on the distant mountain ahead of us.

And there are no doubt some readers who may have made the pilgrimage to the top of that mountain to visit the observatory and get a peek at the famous Hale Telescope.

But too many of us locals who've seen the observatory don’t fully appreciate its magnificent history. We see only some nondescript white object on the hill from the freeway. We might visit that massive dome, and peer, through the glass dimly, at a giant steel contraption that vaguely resembles our idea of a telescope. Unimpressed, we walk away, almost disappointed.

This, to us science folk, is the equivalent of walking up to the Grand Canyon or Botticelli's Venus or the Brooklyn Bridge, shrugging the shoulders, and then nonchalantly moving on to the next point on the tour.

The history, beauty, and grandeur of those works of art are profound. So, too, with the Palomar Observatory, the Big Eye on the Hill.
It was the culminating jewel in the crown for a man named George Ellery Hale, the greatest telescope builder in the last hundred years and whose telescopes changed the course of astronomy and opened up the heavens in ways never before dreamed of.

Hale was convinced that building big, great scopes would show us things in the skies we'd never seen before, and more importantly, give us deep insights into how the Whole Shebang got started, how it is now, and where it is going.

This belief drove Hale to court the richest and often most eccentric people of the early 20th century - the Rockefellers and the Carnegies - in order to fund his vision for astronomy. His tenacity paid off and resulted first in the building of the Yerkes Observatory near Chicago. But for us in southern California, his biggest accomplishments were yet to come.

It was he who put up the telescopes that put southern California on the scientific map. He was the builder of the legendary Mt Wilson Observatory in Pasadena and, of course, our own Palomar Observatory.

But all the building and planning and begging and necessary development of brand new technologies to make it all work took decades. And it sucked the life out of George Ellery Hale. Passing away in 1938, he didn't get to see the opening of Palomar, a momentous event that happened shortly after World War II.

The journey is a fascinating one and I'm tempted to go on and on about it, like about how thousands of people came out to see the great mirror as it was moved across the nation, or how it took 11 years just to polish that mirror to near perfection, or about all the paradigm-shifting discoveries his telescopes made in cosmology, ...sorry.

If you get a chance to go to the Temecula Valley Film Festival to see The Journey to Palomar, do. It shows on Thursday, September 13 at 8 PM, and Saturday the 15th at 3:30 PM. Both showings are at the Movie Experience in Temecula. For more information, go to www.journeytopalomar.org or www.tviff.com.

If you cannot make it to the film, amazon up one book called The Perfect Machine by Ronald Florence. Scott Kardel, the public affairs coordinator at Palomar calls it "THE book" on the building of the observatory.

One way or another, you can always plan a visit to our own great historical landmark. See for yourself both the dome and the telescope, both engineering marvels. And keep this in mind: This is no retired big leaguer. We are not looking at the grave of Babe Ruth or a Lincoln Memorial. Because of the new technologies of CCD imaging and adaptive optics, all the scopes on Palomar Mountain are still making discoveries; they are still on the forefront of modern astronomy. So go, and enjoy the glories of astronomy and America past, combined with the never-ending excitement of cosmology's present - and future.]]>ritter777@gmail.comNone2007-09-16T12:26:44-07:00http://www.firstlightastro.com/skiesabove/files/3a99cc74f1c3eb1dd833837d9aee9ced-43.php#unique-entry-id-43http://www.firstlightastro.com/skiesabove/files/3a99cc74f1c3eb1dd833837d9aee9ced-43.php#unique-entry-id-43Our Moon has been revolving obediently around this planet since way before we ever got here, and when we did get here we immediately recognized its inherent ability to be a great timekeeper and fine nightlight, and exalted it to A-list celebrity status.

But in all those years legends grew up about what Shakespeare calls our "sweet moon," some of which, it turns out, are not exactly brimming with truth. Let's look at some.

#1. The Moon is seen only at night.

Many believe that the Sun is out during daytime, and its counterpart the Moon is, contrariwise, only out at night. Well, the Moon knows no such manmade law. It is going around this planet, taking its blessed time, and cares nothing as to when or where it is seen. Sometimes it is over the dark side of the earth; those times we see it at night. Other times it is on the same side as the sun, the daytime side, and we can see it then if only we know where to look.

Look for it yourself in the next couple evenings in the southern skies in the 5 o'clock hour, about 30 degrees above horizon. See it there in all its quarter moon glory - during the day.

#2. The Moon used to be used as a timekeeper, but those days are gone.

For our western culture, forgetful of the sky above and drowning in digits and technology, we have just vague leftovers remaining from those days when we used the moon for timekeeping.

One bit of flotsam that is an unknown nod to those bygone days is the word "month." It takes just over 29 days for the Moon to begin repeating its phases, not coincidentally the period of time we call a "month," named for that cycle of the moon.

But there are several cultures that still today use the movement of the Moon to keep time and mark the calendar.

Case in point: The 9th month of the Islamic calendar, Ramadan, has just begun. It is a month of daylight fasting for Muslims. And it begins at the first site of the youngest sliver of a Moon, just after New Moon, the time our satellite passes in front of the Sun in its orbit around us. Moreover, the varying dates for Passover and Easter owe their reckonings to lunar movement.

#3. Since the Moon moves in front of the Sun every month, we probably have a solar eclipse every month.

That would be true if the Moon moved directly in front of the Sun every month. But our satellite's slightly tilted orbit takes it just above or just below the Sun most of the time. Because of this, there are usually just one or two solar eclipses somewhere on the planet in any given year.

#4. The best time to see the Moon through binoculars or a telescope is Full Moon!

As a matter of fact, one of the worst times to scope out our satellite is during full moon. It is completely front-lit, thus losing all its wondrously detailed surface features. See it, if you can, at First Quarter, the phase it will happen to be in during the next few days. It is then that the oblique angle of the sun's light raises to life so many craters and valleys you feel you could reach out and touch it.

We see our Moon so often that we easily take it for granted. But if you can take another look at it, do. Examine it, study its history. It is a wonderful work of art worthy of the time.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-10-08T12:24:54-07:00http://www.firstlightastro.com/skiesabove/files/13495085b06c3b9a8c627f1674c21ea4-42.php#unique-entry-id-42http://www.firstlightastro.com/skiesabove/files/13495085b06c3b9a8c627f1674c21ea4-42.php#unique-entry-id-42There is so much attention in astronomy given to the evening skies that we often forget to mention that there is a morning sky, as well. To all those who wake at or before the crack of dawn to brave the traffic or open the store, to those who might be getting off work and making their way home in the wee hours, this column is for you.

One of the first objects our early bird readers may have noticed in the last month is a bright - very bright - "star" rising before the sun. That is Venus, our Morning Star. But wasn't it Venus that was the Evening Star just months ago, setting behind the sun in the east? What's it doing over here now, leading the sun?

It was doing what it does best and what it has been doing for countless eons, dancing around the Sun in its orbit. And since summer it has moved by us, in front of the sun, over to the other side. Thus, it now seems to lead our star through our skies rather than follow it. And the best time to see it as it leads that celestial race is in the morning before sunrise when the sky has not yet been blotted out by its starry partner.

Since our sister planet is still moving farther and farther over to the "right" side of its orbit we can observe over the next month how it rises earlier and earlier each morning before the sun. This won't go on forever of course. Venus will have to swing around back behind the sun to the other side to eventually again become our Evening Star. But don't hold your breath. She is booked as Morning Star into the next year, and won't be making an encore appearance as Evening Star until next summer.

One of the most obvious, if also very slow, processes occurring over the next couple months for our early rising readers is the sun's migration south for the winter.

It's been going on for a while, but since the sun is rising later and later every morning it is more convenient for morning commuters to notice.

Of course both the sun's delayed rising and its slow trip south are due to the tilt of our planet. We are tilting more and more away from our fiery gas giant. We are approaching North American winter. And as we do, the sun rises more and more southerly each day. And its rise is more and more parallel with the horizon, not the near straight up shot it is during summer. And it travels lower through the sky each day. Result: Less sun, less warmth, more dramatic shadows, more in-your-face sunshine.

Now migration of the sun is not restricted to the Morning Folk. Those who observe the setting of the sun will notice a similar effect in the west. The sun will set earlier, farther south and at a sharper angle. All making a homeward bound commute considerably less pleasant for them, as well.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-10-21T12:22:57-07:00http://www.firstlightastro.com/skiesabove/files/3a1e9c4c733aa259069b6b56d6e149a6-41.php#unique-entry-id-41http://www.firstlightastro.com/skiesabove/files/3a1e9c4c733aa259069b6b56d6e149a6-41.php#unique-entry-id-41Many of us have spent some time - OK, maybe too much time - playing with a computer program called Google Earth, available for free from Google for both Mac and Windows platforms. It is a detailed map of earth - that's it - but it is absurdly addictive for those of us who like to explore. Zooming down to just about anywhere on the planet, down to street level using satellite photos, is a virtual explorer's dream.

Well, as if it could get any better, it just recently did. Attached to the latest version of Google Earth is Google Sky, which attempts to do the same things for the heavens as Google Earth does for the planet.

Only now we're not globetrotters, skipping over the continents to see cities and mountains and monuments. Here we zip around the starry skies and explore the natural wonders there.

Opening up Google Sky will give you what seems like just a random array of white dots against a backdrop of constellations. Don't let the elementary school appearance fool you. What you are looking at is rich in big-person information.
Zooming into any area will reveal wall-to-wall stars of all colors and brightnesses. Here you will see the stars in their true colors: reds, whites, yellows, and blues.

Click on any highlighted named object and out pops a window of information about it, including type of object, description, and distance. And since Google is in charge here, there are links galore to online articles and images and blogs on the object you picked.
And, just as in Google Earth, you can add a variety of layers over the viewing area to enrich the exploring experience. This includes a layer for new backyard astronomers, a Hubble Showcase, one for the Moon and the planets, a User's Guide to Galaxies, and one called The Life of a Star.

And the background star field is no fake computer generated field, oh no.

During the 80's and 90's astronomers needed a highly detailed visual record of the sky, one reason of which was to help direct the celebrated Hubble Space Telescope though the celestial sphere. For the Northern Hemisphere, our own Palomar Observatory was used for this sky survey.

Specifically, it was the 48-inch Samuel Oschin Telescope - a stone's throw away from the great Hale Telescope - that was the workhorse behind this endeavor. The millions of star images provided in that project paint the visual backdrop of Google Sky's northern star field.

Try a ride for yourself. First, obviously, make sure you have downloaded the latest version from earth.google.com. Then open it up and fly to Orion and see the rich, star forming area in the Nebula. Veer on over to the constellation Virgo and zoom in closer and closer until you see a lot of fuzzy, but organized clouds. Each of those are galaxies in the Virgo Cluster, millions of light years away, each with its own billions of stars.

"The Life of a Star" layer will take you through the skies to see real images of stars in their various stages, from nursery to supernova remnant.

Or just be an adventurer and discover the beauty of the heavens in an arbitrary way in your own sweet time.

Is Google Sky perfect? No, the program is still in its infancy. Not all stars and galaxies are identified. There are artifacts from the original images that haven't been cleaned up and may be confusing for the novice. And for some reason a placemark for the Japanese Imperial Palace showed up in the constellation Vulpecula, and one for the Reichstag is right there in Ursa Major. I kid you not.

But over all, and considering the price, Google Sky is great fun. It is full of information and brings out the voyager in us all. And if past Google offerings are any indication of where this is going, Google Sky will just get better and better. Have fun!

And until next time, clear skies - real and virtual.]]>ritter777@gmail.comNone2007-11-14T12:20:31-08:00http://www.firstlightastro.com/skiesabove/files/a6d61d8e37f5edb2951fb51fdb61ea53-40.php#unique-entry-id-40http://www.firstlightastro.com/skiesabove/files/a6d61d8e37f5edb2951fb51fdb61ea53-40.php#unique-entry-id-40In the next few days we will celebrate the 435th anniversary of The Event, an seemingly innocent incident which took no more effort than for one man to look up into the sky and see something new - and then act on it. That deed was one which helped change the face of astronomy forever and helped us all see the cosmos in a brand new light.

In November 1572, Tycho Brahe was just a 26-year-old Danish nobleman who had recently become interested in astronomy. He became fascinated in the discipline after seeing an eclipse (as do many people), and continued to delve into it - but especially after what he saw on that fateful day.

In Tycho's day there was a profound paradigm shift in western thought being birthed. Whether this new arrival would survive or not was yet to be seen. Tycho unwittingly made sure it would live by happening to be in the right place at the right time.

The prevailing worldview concerning the universe then was that the entire cosmos went around us, around the earth. It was the geocentric theory. There are several reasons why nearly everyone accepted it. For one, it actually does appear that way, it does seem that the entire heavens go around us like a giant starry-speckled sphere around our static planet. But, just as importantly, the philosopher Aristotle had said it was so. That Aristotelian philosophy of nature had been the great fortress in western thought for centuries.

That great imposing wall of geocentrism had begun to weaken - just decades before Tycho arrived on the scene - when a Polish monk named Copernicus had the gall to propose that the earth actually went around the sun!

There were a couple reasons why Copernicus's heliocentric ideas were not accepted right away. One was that this was before the invention of the telescope and there really was no convincing evidence proving we went around the sun. (It's tougher to prove than you think!) Another was that it was just plain asking too much. People love their worldviews, and feel safe there, unchallenged.

So how did Tycho affect it all?

Aristotle's views of the heavens included the belief that they were immutable, unchanging. For there to be a change up there implied Aristotle may have been - horror of horrors! - wrong! When Tycho looked up in that sky on the 11th of November 1572, he saw a bright and shiny new star, a "stella nova." Located in the constellation Cassiopeia it was quite literally a star not seen before.

Most dismissed the nova as some atmospheric phenomenon, not some event amongst the starry hosts. But as Tycho observed it, and took data on it, and analyzed that data, he realized that is was indeed in the distant starry heavens. There was something new over the sun.

It turns out what Tycho saw was what we now call a supernova, the intensely energetic death of a giant star. The remnants of that blast can still be seen today.

This was actual evidence needed to start the destruction ball swinging on Aristotle's universe. A few decades afterwards, Galileo, using his first primitive telescopes, got more evidence that the geocentric way of thinking was on its last legs by observing the craters on the Moon, moons around Jupiter, the phases of Venus, and even blemishes on the Sun - all evidence against Aristotle's view of flawless heavens.

Surprisingly, Tycho did not adopt a heliocentric world view. He had his own system which he felt much better explained all the observations. His universe had the earth as center, with the Sun orbiting around it, but with all the planets orbiting the sun. It wasn't true, of course, but it fit the limited facts of the time.

After Tycho's untimely death Johannes Kepler, Galileo, and Isaac Newton all helped bury the geocentric - and tychonic - systems forever.

But one might arguably say that the whole revolution really heard its first evidentiary shots when a young, ambitious astronomer saw something new in the skies - and acted on it.]]>ritter777@gmail.comNone2007-11-19T12:18:46-08:00http://www.firstlightastro.com/skiesabove/files/3749402157031e64302f893c42ebde32-39.php#unique-entry-id-39http://www.firstlightastro.com/skiesabove/files/3749402157031e64302f893c42ebde32-39.php#unique-entry-id-39There is a comet in the sky tonight which is normally just an occasional no-big-deal visitor to our parts of the solar system, but which for some reason has made quite the spectacle of itself this time around. And it's time for you and friends or family to go out and take a look at the little show-off before it fades away.

Comet 17P/Holmes is a "periodic comet" (hence the letter P in its name). "Periodic" is just astrospeak for "it takes less than 200 years for this guy to go around the sun." Comet Holmes only takes about 7 years to make a complete circuit.

The "Holmes" part obviously is for the man who discovered it. Edwin Holmes, a British astronomer, discovered the comet in 1892 while sightseeing around the constellation Andromeda.

The comet had just had an "outburst," a phenomenon in which a comet suddenly throws out a pile of dust and gas which gets lit up by the sun. This causes the comet to brighten many magnitudes. What may have been visible only through a telescope just hours ago is now so bright it can be seen naked eye. And Holmes was the first to see it.

And that is what appears to have happened in the last several weeks to this normally inconspicuous comet. At the end of October, this tiny little critter suddenly brightened from magnitude 17 to about 2.5 in just a couple hours. Translation: what could only be seen through the best backyard telescopes could now be seen merely by looking up into the night sky.

Now how to find it. Go out tonight and first allow a few minutes for your eyes to adapt to the darkness. Then face northeast. Look up a little more than two-thirds into the sky from the horizon. There you will find a faint circular glowing cloud in the constellation Perseus. That glowball, my comet-seeking friends, is Comet Holmes.

You will not see the expected long tail of the comet. Why? Currently we are passing by Holmes in our orbit. The sun is on one side, Holmes is about 150 million miles on the opposite side. So far, no problem.

Now the tail of a comet is caused by the sun's solar winds blowing the expanding dust and gas away from the comet, out to the farther reaches of the solar system. Since we are in the line of sight, the tail is being blown away from us, not to either side. We're looking at the comet "head on."

Use a telescope or binoculars to bring out more of the details. Binoculars are enough. And keep an eye on it in the next weeks. Will it just fade back into anonymity? Will it have another outburst? Will its tail become more visible? Will its hue continue to change in subtle ways as has been observed lately?

These are all questions you can tease your young astronomer son or daughter with. Comet Holmes might be the one minor cosmic event that sends a youngster into a future in astronomy, perhaps some day to discover a comet of her own.

Until next time, clear skies!]]>ritter777@gmail.comNone2007-12-02T12:16:31-08:00http://www.firstlightastro.com/skiesabove/files/a8a7f4335f2738a3ca7ebb8ec7ee3b31-38.php#unique-entry-id-38http://www.firstlightastro.com/skiesabove/files/a8a7f4335f2738a3ca7ebb8ec7ee3b31-38.php#unique-entry-id-38Have you spotted the sun lately? No, I don't mean a naked eye glance up to our blinding friend. I mean, have you recently seen a satellite image of our sun or have you seen it through a filtered telescope? If so, you'll have noticed something. Actually you will have noticed a lack of something. It seems the sun has lost its spots.

Go to the website for the Solar and Heliospheric Observatory, SOHO. (It is at http://sohowww.nascom.nasa.gov/) There you will see for yourself one cleaned-up, near-pristine sun. It's like someone took spot remover to it and wiped away any imperfections. The sunspots are all gone!

Where did they go?

Right now we are in the middle of an expected quiet period for our star. The sun actually cycles through periods of sunspotting. It takes about eleven years to go through the cycle from lots of spots to nearly none and back to heavy. The last spotty period, also know as Solar Max, was back in 2002. Back then the sun was speckled like a leopard.

Since then the spots have gradually diminished to a point where there are essentially none today. They will return, though. The next Solar Max is expected about 2012.

But what are the sunspots and why do they come and go? It has to do with magnetic fields.

Planet Earth has a magnetic field that is relatively nice and stable and, like a giant protective bubble, diverts incoming nasty solar particles around us. It really is a wonderful effect of our planet's interior makeup.

The sun has a magnetic field, as well, a monstrous one. But it has this spinning problem. Earth spins at the same rate everywhere. Whether one is in northern Alaska or on the equator, it takes 24 hours to make one trip around.

On the sun, it ain't so. The equator of the sun spins around faster then the poles do. It can do that because it is not a solid.

But - long story short - this means the sun can actually wrap itself up in its own magnetic field. It is not unlike those rhythmic gymnasts who, if they spin fast enough, can get wrapped up in their flowing ribbon thingies.

These wrapped up magnetic field lines can squirm around like giant magnetic worms along the sun's surface. When one kinks, like when one kinks a water hose, the magnetic kink can break through the surface of the sun.

Where this happens, the sun's heat has a tough time breaking out of the sun and it is cooler there. We see these cooler areas as sunspots.

A lot of sunspots means the sun is pretty active; it is a jumbling, living, energetic surface full of energy and tangled magnetic lines and spots and prominences and flares and coronal mass ejections. Oh my!

What a mess!

But eventually it reorders itself. The sunspots disappear. Things quiet down. The sun takes a breath before the next act. We are there now, at the sun's intermission.

What does the next Solar Max hold? It's coming, there is no getting around that. But will it be a milder one as some scientists predict, or will it be up to 40% worse than the last as some computer models are showing us?

Will extra heavy activity have a minimal effect on earth's climate, or will it trigger something more profound, especially since the climate situation is getting more precarious all the time?

One way or another, for the die-hard astro fans out there, watch the sun over the next 5 years and see the slow return of the spots for yourself. But use a filter!]]>ritter777@gmail.comNone2007-12-12T12:13:11-08:00http://www.firstlightastro.com/skiesabove/files/c02efa425f8915540adcb2e6533ff783-37.php#unique-entry-id-37http://www.firstlightastro.com/skiesabove/files/c02efa425f8915540adcb2e6533ff783-37.php#unique-entry-id-37'Tis the season when many Americans celebrate a special birth that took place more than 2000 years ago. Some wise men were led to the birthplace by a star in the east, what many of us call the "Star of Bethlehem."

Well, we who love the night sky will have plenty of stars in the east to watch this Christmas season. They portend nothing nearly as significant as that other star, but they give us reason to pause in wonder, nevertheless.

If you are patient - and dressed warmly enough - you can behold the rising of three planets, "stars" as they were called in days of old, rising in the east throughout the night this month.

First up is Mars. It first peers over the eastern horizon at about 6 PM. It is at its closest to us this year this week, a mere 55 million miles away. You will notice right away that even though it is "close," it is not as "big as the Full Moon" as those false internet rumors tell us annually.

It is easy to spot, a lone, bright, pinkish "star" to the left of Orion and below the Pleiades. Should you have a telescope or be getting one for the holidays, take a look. Now is the best time. You should be able to make out surface features on the Red Planet, we are that close.

Wait a few hours and the earth will have turned right into Saturn's neighborhood. Rising in the east at about 11 PM, this gas giant is not as bright as Mars, but through a telescope will make your jaw drop.

Wait until this "star" rises higher into the sky before you take a look, though. The heat from the horizon and the turbulence it brings can make a mess of seeing. If you can't stay up past midnight for that, fear not, for I bring you tidings of joy. Over the next months Saturn will keep rising earlier in the evening. By about February the Ringed One will be perfectly placed for the best evening viewing.

Now, for the faithful and stout-hearted, if you can wait until about 4 in the morning you can spot our third "star in the east," blazing Venus. She will rise in full glory before sunrise. It might be more convenient for you to just wake up early some time in the next couple weeks and see all three together in the early morning skies.

In the five o'clock hour, before sunrise, all three will be strewn across the sky in almost a straight line from east to west, like celestial Christmas lights; Venus in the east, Saturn up above, and Mars ready to set in the west.

All three will define the line astronomers call the ecliptic, the imaginary line that the planets all ride along throughout the year. By summer, Jupiter will be on this same line in our evening skies.

Here is a challenge: Be a wise man - or woman - yourself this Christmas season. Take a break in the next couple weeks from the hustle and bustle of this busy, stressful time of the year and go outside during the evening. Take a deep breath, look up at a star in

the east, and peacefully reflect on the greater things in life. It'll do you a world of good.

Until next time, clear skies - and blessed holidays!]]>ritter777@gmail.comNone2007-12-30T20:43:59-08:00http://www.firstlightastro.com/skiesabove/files/003776a488870d3861751aca5eb54336-36.php#unique-entry-id-36http://www.firstlightastro.com/skiesabove/files/003776a488870d3861751aca5eb54336-36.php#unique-entry-id-36Allow me to be a two-faced for a moment - in a good way. Like Janus, the ancient Italian deity who is depicted with two faces, one looking forward and one looking back, and for whom our month January is named, let's take a quick look back at 2007, and get ready for some events happening in 2008.

The last year in astronomy was not too too exciting for amateur astronomers. I mean, we didn’t have any local solar eclipses, or devastating supernovae, or spectacular meteor storms. But we did have our planet buddies to keep us company, and several nice comets. They, and the ever present starry firmament, are there every year and always making looking up well worth the effort.

It was a very good year as far as the technological side of astronomy is concerned. We touched down on Titan, Saturn’s largest moon, and saw for the first time its cloud-covered surface. Streams of data are still coming back from spacecraft on or around Mars and Jupiter and Saturn, all giving us unprecedented looks at these ancient planets, all helping us to refine our knowledge of our solar system, a sui generis work of art.

Astronomers also found more planets outside our solar system. Their discoveries bring joy to two groups of people: to one group who exclaims "Lots more planets means lots more chances for life!" and to those who because of the hellish nature of these new planets reason, "There's no place like home... There's no place like home..."

And after a 13-year wait, we saw first signs of life in the world's largest scientific instrument, the Large Hadron Collider in Switzerland. This critter, we hope and pray, when fully operational will be able to simulate conditions in the universe when it was a mere babe, just billionths of a second old.

Now for this coming year, 2008, there will be all kinds of wonderful techie and cosmological stuff revealed and discovered, to be sure. But what can we backyard astronomers do in the meantime, between press releases? Here are some suggestions.
On February 20, at sunset, the full Moon will rise in the east. So what? It will be announcing the opening act of a total lunar eclipse. We in Southern California will be able to watch the whole play unfold over the next several hours. Make sure you see it. We will not have another total lunar eclipse until late 2010!

If you can get a look at Saturn through a telescope this spring, do. Next year will be disappointing. Why? Saturn, like most planets, has a tilt. This year it is still slightly tilted with respect to us, so the rings still are a thing of beauty. But next year we see the glorious rings edge-on and they, in essence, vanish. Boring!

Coincidentally, Saturn will be right next to the Moon during February's eclipse extravaganza.

Here are several things you might want to try this year, as well. One would be to commit to seeing a meteor shower; they are scattered throughout the year. Another might be to see an asteroid, like the great Ceres. Or you can attempt to see all the planets in a calendar year. Perhaps subscribe to an astronomy magazine like Astronomy or Sky and Telescope. Read newspaper articles on the latest cosmological discoveries. Have deep discussions with friends and family about the philosophical and even theological implications of all that is going on in the heavens.

Learning from the past and committing to a future of deeper understanding and appreciation of the cosmos is a win-win situation. It helps us see better our place in the whole wonderful Grand Scheme of Things.

Until next time, clear skies, and a happy 2008!]]>ritter777@gmail.comNone2008-01-13T20:41:38-08:00http://www.firstlightastro.com/skiesabove/files/2bd1709e139e27c4d78f10f17b56a284-35.php#unique-entry-id-35http://www.firstlightastro.com/skiesabove/files/2bd1709e139e27c4d78f10f17b56a284-35.php#unique-entry-id-35This Monday marks the anniversary of an historic event in interplanetary space travel. It was a mere three years ago when the Huygens probe landed on Titan, the largest and arguably the most mysterious of Saturn's sixty moons.

The probe was named for Christian Huygens, a Dutchman of extraordinary talents. Neither he nor the namesake probe are well known by the general public, but both played an important role in moving us forward in this discipline of astronomy.

Huygens lived in the 17th century, the real kickstart century for the scientific revolution. He was well educated in... well, a lot of things. He studied law and mathematics at first but eventually wandered into physics and astronomy. He dabbled with and invented and engineered two types of instruments that play huge roles in astronomy: clocks and telescopes. He was a man of many hats. In the truest sense of the term, he was an educated person.

More specific to what we are talking about now, it was in the late 1650's that the overactive Huygens developed a better way to grind lenses and with these constructed some wonderful telescopes. He used his refined telescopes to confirm that Saturn's strange and unexplained rings were not appendages growing out the side of Saturn, nor were they one solid disk of material. They were collections of innumerable "rocks" orbiting about the planet.

Moreover, with his scopes he discovered a moon around Saturn, a behemothic moon later christened Titan.
As time went on and telescopes got better, it became clear that Titan was a special satellite. It was more than 1000 miles larger across than our own moon. It is even larger than Mercury. But what set it apart was not just its extra large girth - it was a moon with an atmosphere.

Before we sent the Cassini-Huygens spacecraft there, not much was known of Titan. Its hazy atmosphere prevented scientists from seeing the surface. What was below? Was there just a rocky surface? Were there lakes and oceans of methane as predicted by temperature and pressure data?

When NASA sent the Cassini spacecraft to Saturn in the 1990's they efficiently decided to kill two birds with one stone. On board the massive Cassini spacecraft they would piggyback a smaller bundle of instruments - a bundle with a parachute.

This probe, named Huygens, would be released from Cassini to fall onto Titan, recording the whole journey along the way.
Well, three years ago Huygens fell to its destination and landed on the mystery moon, dropping through the haze and landing successfully on its surface. What Huygens and the Cassini spacecraft flying above discovered was not exactly what planetary scientists were hoping for.

It had long been thought that Titan might be covered in shallow seas of methane and ethane, hydrocarbons which are gases on our planet, but which on bitter cold Titan would be liquid.

Although Huygens snapped some pictures of what seemed to be liquid-worn terrain, the oceans were not to be found. Such is science; sometimes revealing the truth about something can take some the fun out of it.

Huygens also sent back images from the frozen surface itself, and eerie place surrounded in a kind of "sand" made of water ice.

The little trooper of a spaceprobe breathed its last after just an hour and a half on the surface. But Cassini, the mothership that brought Huygens to Titan, is still making the papers, sending back those incredible images of Saturn and snapping pictures of Saturn's moons as it flies by them. Just last week Cassini flew by Titan again, revisiting Huygens' final resting place.

If you can, take a virtual trip to Titan and Saturn at saturn.jpl.nasa.gov, and see the images both spacecraft have sent back. And if you can, grab a telescope this season and discover for yourself both the ringed giant Saturn and tiny Titan next to it, just as a young Christian Huygens did over 350 years ago.]]>ritter777@gmail.comNone2008-01-27T20:37:57-08:00http://www.firstlightastro.com/skiesabove/files/86c2784ce4a08ddac85d4c67cdf77adb-34.php#unique-entry-id-34http://www.firstlightastro.com/skiesabove/files/86c2784ce4a08ddac85d4c67cdf77adb-34.php#unique-entry-id-34People steeped in public education swim in a swirling sea of buzzwords and phrases. One of those phrases is "scientific literacy." It seems that we Americans are a wee lacking in the area of scientific literacy, knowledge of the basic terms and facts from the land of science. But we do not have to belong to the Club of Illiteracy, oh no! We can rise above that. So, in addition to the usual sky information that we normally see here in this column, maybe this year we can, on occasion, devote some time to laying down a solid foundation in the grand science of astronomy.

Ready?

Which planets have rings? Well, of course we know that Saturn has rings. For hundreds of years it was the only planet with rings. But recently we have discovered that Saturn's neighbors, the so-called gas giants, also have rings. But they are so faint they weren't discovered until a short time ago.

Uranus was the first planet after Saturn to show us its rings, although we first had to pry the fact from it. In the mid-70's astronomers observed that distant stars would flicker just before and after Uranus passed in front of them. The reason must have been faint rings cutting off the starlight. In 1986, the spacecraft Voyager 2 flew by Uranus and sure enough, there were the nearly imperceptible rings.

It turned out Jupiter had them, too. They were discovered in Voyager 1's flyby in 1979. But don't expect to see them with your backyard telescope. They are essentially made of dust. Only the biggest scopes here on Earth can catch a glimpse of them.
Then, not to be left out, Neptune revealed his rings. Suspected to exist by the same flickering of stars as Uranus' rings showed us, Voyager 2 confirmed them in 1989. It appears that all the big guys - not just Saturn - wear rings.

What is the hottest planet? Most would suspect, intuitively, that the planet closest to the Sun would be the hottest, to wit, tiny Mercury. And Mercury is hot, to be sure - very hot. At its equator it can get to 800 degrees Fahrenheit.

But even as hot as that little guy is, it isn't the winner. Venus is actually hotter - averaging almost 900 degrees Fahrenheit.
But how can a planet more than 50 million kilometers father away from the sun than Mercury be hotter? Because Venus is swaddled in an atmospheric blankie. Poor Mercury has no atmosphere to hold onto the heat, which is why its dark "nighttime" side gets to 300 below.

But Venus has an extremely thick carbon dioxide atmosphere. And carbon dioxide has a notorious ability to hold on to heat; it is the prime suspect in global warming here. This is precisely what is happening on Venus, the warmest planet in the solar system.

How does the sun burn? It was believed since time immemorial that the sun was hot because it was burning stuff, just like fires do here on earth. But if that were what was happening it would have had only tens of thousands of years of stuff to burn, not b-zillions. There had to be another, more efficient way. It took Einstein and his contemporaneous colleagues to figure this one out.

A group of really smart people of his time discovered that the nucleus of an atom stores a wealth of energy, a great wealth, a fortune. It seems that if we rip apart giant nuclei, or smash together very tiny ones, a tremendous amount of energy is liberated.

That is what happens up there in the sun. At its very hot and high-pressure center - the core - tiny little hydrogen nuclei are forged together to form helium. In the process, a prolific amount of energy is released and eventually makes its way to the sun's surface, released now into space.

There is enough hydrogen left at the core for our sun to burn nicely for several billion more years. No need to feed those flames, all is well.

Feel a little more "literate"? Hope so.

Until next time, clear skies!]]>ritter777@gmail.comNone2008-02-10T20:34:57-08:00http://www.firstlightastro.com/skiesabove/files/12cb53b8b4e58261f7d4e218c09bf7fe-33.php#unique-entry-id-33http://www.firstlightastro.com/skiesabove/files/12cb53b8b4e58261f7d4e218c09bf7fe-33.php#unique-entry-id-33Next week, on Wednesday the 20th, we are all invited to a celestial phenomenon for the whole family. At about 6 in the evening, in the eastern skies, our Moon will rise full but not like it usually does. There is a twist tonight. As it rises it will be crawling into our shadow in an event we call a total lunar eclipse.

The timing of this particular eclipse is perfect for those of us in southern California, and we won't get it this good again for a couple years. We essentially get to see the whole show at a reasonable hour. Now we may miss part of the first act, but that's OK; the opening act is a snoozer. Here is a synopsis of our play.

Every month the Moon makes one trip around our planet. During that circuit it manages to get itself on the side of the earth opposite the sun. When it does this it risks going through our huge shadow. Because the Moon's orbit is slightly tilted, it doesn't always manage to hit the shadow, but it will on the 20th, and thus we have ourselves an eclipse.

The whole process takes several hours, which will give you some time not only to relax and enjoy it, but some time also to observe some other cool science things.

When the moon first peeks over the eastern horizon, it will already be fully into what is called the earth's "penumbra." The penumbra is just the partial shadow an object lays down. You have unwittingly experienced it yourself. As the sun rises in the morning from behind a distant hill or mountain, we do not see the whole sun yet. When it first shows itself, when all we see is part of it, we are in the partial shadow - the penumbra - of the earth. The sun is neither completely hidden from us, nor is it blazing in all its full glory.

This is what the Moon is experiencing when an eclipse begins. For someone on the Moon, the sun appears to be moving behind the earth. But a penumbra is still so bright, most of us would never notice it.

It isn't until the Moon moves completely into the full shadow, the umbra, that the show really gets underway. This will have just begun as we see the Moon rising Wednesday. You will see it maybe a third covered in the dark umbral shadow.

Notice at this time, too, after the sun sets, how the whole eastern horizon seems to be lifting up in a purple haze. That curved semi-darkness is the earth's shadow, the same shadow the Moon is moving into.

Over the next hour or so, until about 7, watch how the shadow crosses the face of the Moon, darkening it. Notice also how the shape of the shadow is curved. It is always curved. This fact led ancient Greeks to believe the earth was a sphere, the only shape that always has a curved shadow.

The darkness will last for about an hour, it takes that long for it to pass through. It is at this time you might notice that the Moon takes on a reddish appearance. That would be because our own atmosphere bends the light from the sun, like a lens, toward the Moon. The only wavelengths from the sun long enough to make it through all our atmosphere and get the free trip to our satellite are from the red end of the spectrum. More poetically, all the world's sunsets are bleeding towards our Moon.

Just before 8 PM, the Moon will have reached the other side of our shadow. The umbra will begin to give way to the penumbra, all the main action having been completed. By about 9 PM the umbra is gone; by 10 PM the nearly invisible penumbra will fade by and the entire show is over.

This will be the last time to see a total lunar eclipse at a reasonable hour for a couple years. You and your family, or school class, or scout troupe might want to make it a nice evening of observation of one of the heaven's free dramas.]]>ritter777@gmail.comNone2008-02-24T20:31:27-08:00http://www.firstlightastro.com/skiesabove/files/d415023eba0c44c548cf8fa4dbb1b62c-32.php#unique-entry-id-32http://www.firstlightastro.com/skiesabove/files/d415023eba0c44c548cf8fa4dbb1b62c-32.php#unique-entry-id-32Forty years ago today, a paper came out of Cambridge University in England announcing to the world the discovery of yet another bizarre heavenly object, a mysterious "pulsing" animal found quite by surprise. We now call it a pulsar.

It was actually discovered the summer before, in July 1967, by a young postgraduate student at Cambridge, Jocelyn Bell. And as is common in the sciences it was discovered without being looked for. She and her thesis advisor had been doing radio astronomy on far more distance objects when out of nowhere popped this little throbbing goblin.

Radio astronomy uses the radio part of the electromagnetic spectrum to "see" things out there, things invisible to our eyes. While searching deep space with her radio telescope she came across a strange pulsing of radio waves coming from an unknown point in space. Like a heartbeat it was very regular, unlike a radio noise one might expect.

It was such a regular pulse that it was suggested the signals might have been from an intelligent source, perhaps an alien civilization. Tongue firmly in cheek, the strange discovery was first called LGM-1, for Little Green Men.

The humor aside, the object was a mystery. But shortly after the release of the paper, astronomers figured out what it was. It turned out that the pulsar was just another stellar object we already knew about, only seen from a different point of view. It was a neutron star. But what is that exactly, and why do some pulse?

A neutron star is the core remnant of a giant star that went boom. When a massive star dies, it blows away its outer layers in a giant explosion called a supernova. But the core implodes into a superdense ball of neutrons.

When I say superdense, I mean superdense. A cubic inch of this stuff would weigh in at 100's of millions of tons. That, my friends, is superdense!

Moreover, when one forms it spins just like the star it came from, but it spins fast. You guessed it... superfast. Like an ice skater bringing in her arms to spin faster, the neutron star, shrunk to the size of a large city, can spin fast - hundreds of times a second.

This high spun neutron star has a north pole and a south pole, the result of an intense magnetic field. It is out of these poles that radio waves spew.

This all leads us back finally to the pulsar. You might already be able to figure out what those pulses are. If the neutron star is spinning like a top but the magnetic field is slightly off axis, you can see how its radio beams could sweep out an area like the searchlights at a world premiere.

I'll use the classic lighthouse analogy as an illustration. As the beam of light from a lighthouse sweeps around and around, those on the horizon - in the line of sight - see what appears to be a regular pulse of light.

That is what a pulsar is like. It is a neutron star whose expelled radio blast is in our line of sight. We see the "pulse" each time it sweeps by. Other neutron stars could no doubt be pulsars if they would just line themselves up with us.

Once they were found, astronomers went looking for them and found them by the bucketsful.

As to Jocelyn Bell, her faculty advisor got a Nobel Prize for his work in pulsars. Jocelyn was passed over. Hmm... At any rate, her discovery of the pulsar has probably inspired many young women to take up a discipline long held captive by men.

Someone say "Amen!"

Who needs a Nobel Prize, anyway.

Until next time, clear skies!]]>ritter777@gmail.comNone2008-03-09T20:28:53-07:00http://www.firstlightastro.com/skiesabove/files/ccbdce1338702e6860d7260557bbf523-31.php#unique-entry-id-31http://www.firstlightastro.com/skiesabove/files/ccbdce1338702e6860d7260557bbf523-31.php#unique-entry-id-31There was a day not that long ago when the only objects in the sky were the Sun, the Moon, the planets from Mercury to Saturn, and the stars. That was it. Those were all the animals in the celestial zoo.

Where were Uranus, Neptune, tiny Pluto and all those freakish things we have been learning about here over the years - galaxies, pulsars, quasars?

Their existence, in the eyes of humankind, was not known until the advent of a tiny tool we call the telescope, a tool that allowed us to spot these anomalies heretofore undetected by mere naked eye observation.

It was 227 years ago this week that the famed astronomer William Herschel, using a homemade telescope, doubled the distance to the borders of our solar system, extending it outward over another billion kilometers beyond Saturn. It was he who discovered Uranus, the seventh planet.

Usually I tell you where in the sky you can find the featured object. Sadly, Uranus at the moment is on the opposite side of the sun. That means it is now up only during the day, right next to our blazing star. To avoid a lawsuit I would recommend not looking for it. The resulting blindness would prevent you from finding it later this year when it claims the night skies once more.

As to its discoverer: William Frederick Herschel was born in Germany but in his teens took up residence in England. He, like many well-off gentlemen of his time, had a penchant for dabbling into the different disciplines. He was, for example, an accomplished musician. It was that an art that led him into the land of mathematics.

It was through math that he discovered the amazing world of astronomy. During this time, in his mid-thirties now, Herschel began constructing his first telescopes. He would end up making over 400 in his busy life.

When he was 43 years old, living in Bath, England, he discovered with his own telescope what he thought at first was a comet, but which shortly thereafter was shown to be a seventh planet, the first planet discovered since man was put here.
It had actually been seen before by other astronomers but was mistaken for a star. Herschel noticed in a series of observations that it moved just slightly, hence the initial thought that it might be a comet. But it turned out to be a far more distant heavenly body, a new planet.

Being a loyal Brit now, he named his newfound planet after his king, George III. Yes, the same George who gave the colonies in America so much grief.

Now, let's see how that new planet line-up might sound if the name had stuck: Mercury, Venus, Earth, Mars, Jupiter, Saturn, George. Hmmmm...

It was proposed by another astronomer that the planet should be named Herschel in his honor. Ahem. Thankfully, wiser, more traditional, minds prevailed, and the planet was named for the Greek god of the sky, Ouranos. Despite being more traditional, even that name broke ranks with the other planet names, being a Greek deity rather than a Roman one.

By the way, astronomers prefer to pronounce the planet's name with emphasis on the first syllable, not the second. It is not only preferred but can keep giggling to a minimum when you pronounce it in front of high schoolers. Trust me.

Herschel went on to do a lot more work in his life. He showed that gravity worked outside our solar system by keeping binary stars together. He built all those scopes, of course, some monstrous. He did some amazing studies with the Sun. And he would discover new moons around Saturn and George... uh... Uranus.

And he left behind a legacy, as his son John carried on the family tradition and became a famous astronomer himself.
But there was at least one more planet to be discovered! Alas, that’s a story for another day.

Until next time, clear skies!]]>ritter777@gmail.comNone2008-03-23T20:25:13-07:00http://www.firstlightastro.com/skiesabove/files/05c223dd8ee5924e43df8c3cbf9a01f6-30.php#unique-entry-id-30http://www.firstlightastro.com/skiesabove/files/05c223dd8ee5924e43df8c3cbf9a01f6-30.php#unique-entry-id-30Directly above your head in the evenings this week are two bright stars, twins as the legends go. They are Castor and Pollux, the Gemini dyads, twins from the days of myth.

Actually what you are looking at are their big, bright, hot heads. Castor’s is the bluer one, Pollux's star is a wee pinkish. Their skin-and-bones bodies trail off to the west making the starry duo's constellation appear, in toto, as a rectangle in the sky.

Their story is a typical ancient myth, filled with naughtiness and violence and escapade. One genesis of the Gemini goes something like this: There once was a princess named Leda who was of exceeding beauty. The big god of Olympus, Zeus, saw her beauty and to no one's surprise wanted her real bad. On her wedding night, when her husband was temporarily away, Zeus showed up disguised as a swan (don’t ask) and had his adulterous way with her. Her husband later consummated the marriage after Zeus flew the coop.

This was awkward to say the least, but the result was even more bizarre. She conceived two pairs of twins in a single, apparently very roomy egg. The one pair was immortal because of Zeus' contribution, the other pair mortal.

The boy from the immortal pair of twins was Pollux. Castor was his mortal half brother twin from the mortal side of the egg. The other kids apparently fell into relative anonymity.

The brothers ended up being as close as... well... brothers and shared a full life of boxing and soldiering and general horsing around. One of their fun times together included saving the Argo fleet from one nasty storm. This endeared them to sailors for centuries, and mariners would carve their likenesses into the bows of their ships for protection.

In their last caper together Castor got himself killed, much to the anguish and anger of both Pollux and Zeus. They dealt viciously with his attackers. Zeus afterwards saw that Pollux was deeply distraught and told him to come on up to Olympus. Pollux could get through the Olympic bouncers because his dad was Numero Uno. Castor, however, a mere mortal, was sent to the underworld. Well, this didn't sit well with Pollux - being a way from his brother - and he wheeled and dealed with Zeus until they worked out an agreement where the twins would spend alternating days above in Olympus and below in Hades.

In a poetic way we see that brotherhood in the skies today. Pollux descends below the western horizon almost immediately after Castor, and when they rise in the evening, there is Castor with his good brother Pollux right on his heels.

To astronomers these two stars have a real life of their own, but they are not twins, to be sure. Pollux is an older, redder, giant star, the brighter of the two. It is a lone star but just last year it was confirmed that there was a Jupiter-type planet in its grip.

Castor is another story altogether. Appearing as a single star to our eyeballs, it is "split" into a double star with any backyard telescope. It would be a nice play on the myth if it were just a twin binary, but observing the two with special instruments, it turns out each of those stars is itself a double star. These two sets of twins would be another nice lyrical ending to this sky story but there’s more!

It turns out there is a third, fainter star gravitationally bound to the first two sets of twins, and that that star itself has a twin, too. Sheesh!

That makes the Castor system a triple double system, six stars gravitationally bound, taking anywhere from days to centuries to go around each other in their heavenly dance. Twins everywhere!

Castor and Pollux are easy to spot, but if you cannot see them go out on the evening of April 12th when they and the first quarter Moon line up nicely like, well, triplets!

Until next time, clear skies!]]>ritter777@gmail.comNone2008-04-06