During Saturday morning's Orionids shower, scientists will be watching for shooting stars that pound the moon in fiery explosions.
- The 2011 Orionids occur before dawn on Saturday morning, Oct. 22, 2011. Pictured: a Leonid meteor with a double afterglow from the 2009 shower. (Ed Sweeney/Flickr)
Early Saturday morning, something nutty will be going on in the skies.
The 2011 Orionids, flaming flakes of dust from Halley's Comet, will be darting around the blackness of space like shiny cave fish. When the meteor shower reaches its expected peak right before dawn, skywatchers camping out with their coffee and telescopes could see more than 15 green-and-yellow Orionids per hour.
Meanwhile, over at NASA headquarters, our nation's top astroscientists will be having their minds blown by a much groovier show: Meteors crashing into the moon like kegs of dynamite hurled by an interstellar Donkey Kong. It's like they'll be watching IMAX: Hubble 3D, while junior astronomers encrusted in morning dew will be trying to sneak glimpses of 1979's Meteor through a neighbor's partially closed blinds.
Just listen to how NASA's Tony Phillips describes these lunar detonations:
Cometary debris streams like Halley's are so wide, the whole Earth-Moon system fits inside. So when there is a meteor shower on Earth, there's usually one on the Moon, too. Unlike Earth, however, the Moon has no atmosphere to intercept meteoroids. Pieces of debris fall all the way to the surface and explode where they hit. Flashes of light caused by thermal heating of lunar rocks and moondust are so bright, they can sometimes be seen through backyard-class telescopes.
The main guy in charge of the U.S. Meteoroid Environment Office, Bill Cooke, has caught more than 250 fiery meteor-on-moon impacts. They're kind of neat, he says: "Some explode with energies exceeding hundreds of pounds of TNT." So here's hoping that Cooke and his team capture a couple of these amazing events on film and decide to share. God knows the footage of a lunar meteor flash on YouTube is less than spectacular.
Where should you be looking for the Orionids this year? Somewhere far away from the lights of D.C., of course. Search the eastern skies for a triangle formed by the Moon, red Mars and blueish Regulus. Keep your eyes within the triangle for the best chances of ogling an Orionid.