Don't look now, but the sky is falling.
Or maybe you do want to look; it's harmless and pleasant. Every year at this time, the Leonid meteor shower brightens the sky in the hours after midnight. If the weather is clear and you have an appetite, you may enjoy a quiet display of shooting stars.
We're passing through the debris left by a comet called 55P/Tempel-Tuttle. As pieces -- some as small as grains of sand -- burn up in our atmosphere, they leave brief, bright streaks. They'll appear to come from the constellation of Leo the Lion, south of the Big Dipper.
Unfortunately, the Leonids are unlikely to be much to see this year. "On the peak night you might count a dozen Leonid meteors per hour before the beginning of dawn under excellent conditions," said Alan MacRobert, senior editor at Sky & Telescope magazine. "This one's for diehard amateur astronomers only."
A bright half moon, rising after midnight, won't help. Its light will drown out many of the dimmer meteors.
There's another shower, though, the Geminids, coming around Dec. 14. When they're their best, you may see 100 shooting stars an hour -- if you bundle up.
Be alert; most meteors streak by in a second or less, sometimes in clusters. The best way to see them is to find a nice, dark place with no street lights and as few trees as possible, and look up. You may be happiest in a lawn chair or a sleeping bag. The streaks could appear anywhere in the sky.
It may help if you park yourself so that the moon, rising in the east, is behind you, and you let your eyes get used to the darkness. You may want to find a spot where the moon is blocked by trees or a building, but then part of the sky will be blocked too.
In general, there are more shooting stars in the morning hours because that's the side of the Earth that faces forward as we orbit the Sun, so it's less shielded. While the shower actually peaks tonight, meteors are often spotted several nights before and after.
It's best if you're far from cities, have clear skies, and happen to be looking in the right direction. (Go to our weather page for conditions near you.) Astronomers will tell you that meteor showers are best if you regard them as something to be savored, rather than awed by.
But MacRobert said meteor showers can be great fun.
"The colder it is, the more it's an adventure!" he said in an email. "Just wait till the Quadrantid shower, predicted to be excellent on the morning of this coming January 4th. ... Experienced meteor watchers will be dressing for this like for an Arctic expedition."