23 Jul 2006
Still 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.
09 Jul 2006
Bleak. 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 30â€¦ 40â€¦ 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!
02 Jul 2006
The 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 thoseâ€¦ 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.