A Perseid meteor lights up as it streaks through the Earth's atmosphere, as seen and photographed by Ron Garan while aboard the International Space Station on August 13, 2011. (By NASA)
By Elizabeth Weise, USA TODAY
Get out your thermos and sleeping bag, this year's Perseid meteor shower will peak Saturday night into Sunday morning. It's already "looking very good," in the words of Bill Cooke, who tracks meteors for NASA at Marshall Space Flight Center in Huntsville, Ala.
"Last night we saw about 75 Perseid fireballs. I'm pretty stoked," he said.
The show will begin between 11 p.m. and midnight on Saturday night and continue until dawn Sunday, says Alan MacRobert of Sky & Telescope magazine. "You might see as many one or two meteors a minute" at its height. The shower will gradually pick up over the course of the night and "continue nice and strong right up until dawn," says MacRobert.
Between 1:30 a.m. and 3 a.m., depending on where they live, sky watchers will also be treated to a three-for-one in the Eastern sky. First Jupiter, then the moon and then Venus will rise, says Conrad Jung, an astronomer with Chabot Space and Science Center in Oakland.
As for the weather, the best viewing areas to see the Perseids include Florida, most of Texas, southern New Mexico, the Ohio Valley south to Tennessee, northern Alabama, northern Mississippi, the northern Rockies, and the West Coast, according to the Weather Channel.
Spots where clouds are possible include much of the East, the Upper Midwest, the central Rockies and the Desert Southwest.
If you're still up when dawn begins, "they'll make a nice diagonal line of bright things in the eastern sky," says MacRobert.
The Perseid meteors appear to fall from the constellation Perseus, but are actually leftover debris from comet Swift-Tuttle. They recur each year when Earth passes through the comet's debris trail. Though Saturday is the peak night, the Earth actually started traveling through the debris in late July and won't leave it behind until early August. It's those tiny pea-and sand-sized remnants that cause the shower.
"We only see them when they strike the Earth's upper atmosphere in the last few seconds of their existence, when they blaze up and burn out," says MacRobert.
The best way to observe the Perseids, or any meteor shower, is to find a dark place outside with as little light pollution as possible. Give your eyes at least 10 minutes to adjust to the darkness. Look straight up and be patient. "Shower is really kind of a misnomer," says Chabot's Jung. The falling stars, as they're sometimes called, tend to come more in groups.
Meteor watching can be cold, especially as the night progresses. Bundle up, which is also helpful against mosquitoes: "A sleeping bag makes excellent armor," says MacRobert.
Jung suggests a big thermos of hot chocolate or coffee and "some energetic friends." But don't drink alcohol, as astronomers say it impairs night vision.
NASA will be holding a live online chat during the shower, from 11 p.m. to 3 a.m.
Cooke and his team from the Meteoroid Environment Office at NASA's Marshall Space Flight Center will be online to answer questions. There will also be a live video feed, for those faced with overcast weather that night.
On the Web: www.nasa.gov/connect/chat/perseids_2012.html