Last night at around 11:20 pm, August 12, 2009, Melanie and I drove over to the shore of Lake Erie and set up our camping chairs to watch the Perseid meteor shower. In case you do not know, the name comes from the fact that the radiant point of the meteors is located in the constellation of Perseus. A little farther to the celestial north and they would have been called the Cassiopeian meteors. These meteors are caused by the Earth passing through the debris from the Swift-Tuttle comet. Here is "Sky & Telescope" magazine's illustrations of the radiant point:
The place to look for the meteors is not necessarily in the direction of the radiant. In fact, most of the Perseid meteors we saw last night ran in a 60-degree pie slice that originated in Perseus and was centered on the Milky Way, passing through Cygnus and on down toward the horizon to Sagittarius. The sky was lit fairly brightly because of the light of the city of Erie to the east, and the marina to the west, but the nearest city to the north is in Canada so no light there, and there is no large city to the south of our observing point.
Many of the brightest meteors we witnessed were over toward Venus, in the constellation of Gemini. The best one we saw was nearly in the fireball category as it produced a long, bright vapor trail for 20-30 degrees. It was awesome and almost spooky to see such a violent event without any sound. That meteor occurred around 11:30 pm and ran through the constellation of Boötes. I did not get any photographs of the meteors.
However, I did get a couple really cool photos of the moon and Venus. The moon was in a waning gibbous stage, just a day away from last quarter. In the picture below, you can clearly see the craters along the terminator. The moon was in the constellation of Aries. Photos were taken with my Canon S2 IS Power Shot camera on a tripod.
These two pictures of Venus were taken just a minute or two apart. Notice how far Venus has shifted relative to the background stars in the constellation of Gemini (it is in prograde motion now). Note that Venus is nearly full at this time (slight darkening of the western edge); it exhibits phases as it orbits the sun just like the moon does as it orbits the earth. Mercury shows phases as well since it is also an inferior planet (orbit between the Earth and the sun). Superior planets do not exhibit phases.
We have been experiencing a "year without a summer" here in Erie, with very few days ever getting above 80 degrees. The nights are in the upper 50s and lower 60s. Here is how Melanie braved the cool night air... she didn't appreciate the camera flash.
If you have Perseid meteor photos that you would like to have added, please e-mail them to me and I'll be glad to post them.
- Kirt Blattenberger
RF Cafe Progenitor & Webmaster