When Earth passes through the trail of debris left behind by a comet, bits of that debris catch fire in our atmosphere and streak across the sky in a blazing 3,000-degree flash. Friday and Saturday night, you can watch this in action by catching the annual Leonid meteor shower, which will run through the weekend.
The new moon on Saturday means the skies will be at their darkest. So it will be the better night to see a dozen or so meteors an hour.
They’re called Leonids because they appear to emanate out of the constellation Leo (the lion), which you can find rising in the eastern sky Friday and Saturday night. The meteors might be best seen in the very late overnight hours until dawn, as they rise higher and higher in the sky.
The meteors should be visible the world over. But where exactly to look will depend on where you are in the world. Here’s the view from Washington, DC, at 1:25 am Saturday. They’ll be close to the horizon in the east. (Use a location-based sky map app like Sky Guide to figure out exactly when and where to look where you live.)
By 5 am, they’ll be nearly directly overhead, like so:
The Leonids are the result of the Earth crossing the path of debris left behind by the comet Tempel-Tuttle, which orbits around the sun. These bits of debris are much, much too small to ever make it down to the surface of the Earth. When they hit our atmosphere traveling at 158,000 mph, they burn up instantly.
“Earth meets these meteors head-on because they are traveling through space in a direction opposite to that of our home planet,” Space.com’s Joe Rao explains. “As a result, they streak through our sky at ultraswift speeds. ... About half of them leave visible trains that, in the most extreme cases, can persist for many seconds.”
Once every 30 years or so, the Tempel-Tuttle debris creates an enormous “meteor storm” when the comet passes nearest to the Earth. In 1966, one of these storms resulted in thousands of meteors per hour, Space.com explains. The next one, in 1999, was a bit of a bust. The next big meteor storm from the Leonids is expected in the 2030s, but it may be diminished too, because Jupiter may deflect some of this debris away from the Earth, Space.com reported.
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