Star Points for August, 2002; by Curtis Roelle Good Prospects for August's Perseid Meteor Shower One of the most popular annual meteor showers occurs every August. The Perseid shower has long been a favorite summer event for amateur astronomers. This month the shower is predicted to peak on the night of Monday August 12-13 under favorable conditions. One factor contributing to the Perseids' long standing popularity has got to be the weather. A warm summer evening is a good time for relaxing comfortably while waiting to see a meteor to steak across the sky every now and then. Sure, there are better showers during the year. But try watching November's Leonids or December's Geminids while wearing short sleeves while stretched out on the ground with friends or family members. All meteor showers take place because of comets. As comets approach the sun they lose material as their tails form. When the earth passes through the debris stream left by a comet we experience meteors as tiny motes of cometary dust burn up harmlessly in the upper atmosphere. The comet responsible for feeding the Perseid debris stream is Comet Swift-Tuttle which last returned in 1992. The comet had not been seen since its discovery in the 19th century while Abraham Lincoln was president in 1862. Speaking of the 19th century, I was recently reading a book written more than a hundred years ago by Simon Newcomb. The late astronomer George Abell described Newcomb as a "great American astronomer who laid a foundation of precise positional astronomy based on his measurements." Indeed many of Newcomb's equations are still in use today for calculating orbital motions. In the last year of the 19th century Newcomb tried his hand at writing a popular level astronomy book for the "inquiring layman." In his discussion of observing the Perseids Newcomb writes, "if one sits up until midnight, he will see an unusual number of shooting stars, which move from the northeast toward the southwest." From his statement it is apparent that either amateur astronomers went to bed earlier in the 19th century, or Newcomb was not an avid meteor watcher. Today's amateur astronomers are well aware that the best part comes after midnight when the shower's "radiant" or apparent source of meteors rises higher as the earth rotates. To watch the Perseids you need to find a location where local light pollution from artificial light sources is at a minimum. The more lights there are around you, the brighter the sky glow. The brighter the sky glow the fewer meteors you will be able to see. Your observing location also should be away from nearby trees and buildings that would block your view of the sky. It is important to be comfortable. Thus, a reclining lawn chair is recommended. A few weeks back a local store had a sale in which the purchase of a sleeping bag earned the buyer a free Eddie Bauer portable folding recliner chair with built-in footrest. We needed some sleeping bags so I stocked up. Such reclining chairs are great for observing meteor showers as well as casual sweeping of the night sky with a pair of hand-held of binoculars. Such chairs are marketed under a wide range of competing brands. As midnight passes by an observer may see an average one meteor per minute. The rate should continue to increase toward morning twilight. Keep a pair of binoculars handy to assist you in observing the trains occasionally left by the brighter meteor. If observing in a group you may wish to arrange your chairs so that each person is facing a different direction. That way you will have better coverage since each participant concentrates on a unique section of sky. There are scientific activities that may be performed as well from meteor counting, to photographing meteors with a camera using time exposures, to videotaping possible impacts of meteorites on the moon! For more information about observing projects there is an enormous amount of information available on the web. Here is a brief listing of on-line resources to help you learn more about meteors in general and the Perseids in particular: International Meteor Organization - http://www.imo.net/ American Meteor Society - http://www.amsmeteors.org/ Gary Kronk's Meteor Showers - http://comets.amsmeteors.org/ The Association of Lunar and Planetary Observers - http://www.lpl.arizona.edu/~rhill/alpo/lunarstuff/lunimpacts.html Sky and Telescope Magazine - http://skyandtelescope.com/observing/objects/meteors/article_649_1.asp While meteor showers such as the Perseids may be enjoyed at many levels of sophistication the most popular method is to just sit back and watch the show. There's nothing wrong with having a good time while enjoying the simple pleasure of the night sky on a warm summer evening.