FirstLight Astronomy Club

33°29.6'N / 117°06.8'W / 1190 ft.

Perseids 2012

It's been a long, hot summer and we haven't had a shower in a while. Let's talk about an  upcoming summer shower and how to get the most out of it.
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Of course I am talking about the annual Perseid meteor shower taking place this coming weekend. It's looking like conditions will be favorable this year so let's take full advantage. But first, what are they? It all starts with comets.

Comets don't travel around the sun like planets. They have highly elliptical orbits which take them from very far away from the sun to very, very near the sun. Sometimes the orbit of a comet may actually cross our own orbit. The significance here is that comets also shed dust and ice and gases and other schmutz, much of which ends up traveling around the sun in the same orbit as the comet. When our planet crosses the path of the orbiting schmutz, we smash into those particles like a speeding car into a swarm of bees. 

When that happens, when the countless sand-sized leftover comet particles streak through the atmosphere and vaporize in a flash of light, we have what we call a meteor shower. And as we pass now into the debris field of Comet 109P/Swift-Tuttle, we will see an increase of meteors rocketing through the atmosphere and lighting up the heavens. 

The "peak" of the Perseids - the time we pass through the most crud - happens Saturday night and Sunday morning. It is then when we should (key word: should) see the most meteors, maybe one every couple minutes. But any night over the weekend should be fine to see them. What's the best way?

Well, because of the physics involved with Earth's rotation and revolution and the orbit of the comet, they are best seen after midnight. Sorry. Thankfully, the moon won't ruin things this year since it doesn't rise until very early morning. 

If you can get outside, observing them is the easiest thing ever. You need only to lie down and look up. No need for binoculars or telescope - just look up. You might want to make sure you have mosquito repellant on. And avoid bringing out the phone or iPad; it takes about 15 minutes for your eyes to fully adapt to the darkness, and looking at those will ruin your "night vision" in a heartbeat, making it much more difficult to see the meteors.

Ideally, the Perseids will give us about 50 meteors per hour in a very dark place with no Moon. Light pollution and our inability to see the entire sky bring that number down. But a Perseid meteor, a good one, can be very bright and quintessentially beautiful. 

Go out sometime this weekend and enjoy, maybe with your family, a beautiful and reliable annual shower. 
Temecula Valley High School / Temecula, CA · Some images © Gemini Observatory/AURA Contact Me