Are You Ready for the Perseids Meteor Shower?
The peak of the annual Perseid meteor shower will be Saturday through Monday morning. The falling stars will be in the night sky at a rate of at least 60 an hour. That's a pretty relaxed rate for beginner shower watchers, but some years the streaks through the night sky approach 200 per hour. Everyone hopes that this will be one of "those years." The conditions are good - the Moon is only showing off a quarter of itself and the weather forecast for the Bitterroot Valley and Missoula doesn't show much in the way of clouds. There is a possibility of forest fire smoke producing a hazy sky. In fact, some stargazers reported that condition Wednesday night.
The Perseids shower is the most publicized meteor shower. It happens when Earth passes through dust and rocks left by the passing of a large comet. The Swift-Tuttle comet passed by Earth in 1992 and will come by again in 2126, as it follows its lengthy orbit around the Sun. The comet is about 16 miles wide, so it leaves lots of little particles from its tail. And they are little - some as small as a grain of sand. But when they hit the atmosphere at about 40 miles a second, they burn up. The larger pebbles are magnificent, with brilliant trails.
Get out into an area with a lot of sky - like a field up on the east side of the valley (or up in mountains) and get comfortable. The best times are around midnight and into the morning hours, though I've seen them earlier than that. As your eyes adjust to the darkness, you'll notice even the faint little streaks. Generally, they come out of the northern part of the sky near the constellation Perseus. An added feature early in the night sky this weekend - four planets. Venus and Jupiter early in the twilight, then Saturn and Mars will be visible past midnight. Enjoy.