Moon Marbles


Whenever my parents are stressed, they'll head to the shooting range. My cousins will throw darts, and my brother and sister will lean their anxiety into endless rounds of World of Warcraft. I'd love to be able to say I shoot marbles into simulated lunar soil at 16k mph, like NASA scientist Bill Cooke, but I don't. Not yet, at least.

"We are simulating meteoroid impacts with the lunar surface," he explains. Cooke and others in the Space Environments Group at NASA's Marshall Space Flight Center have recorded the real thing many times. Their telescopes routinely detect explosions on the Moon when meteoroids slam into the lunar surface.  A typical flash involves "a meteoroid the size of a softball hitting the Moon at 27 km/s and exploding with as much energy as 70 kg of TNT."

Cooke's time at NASA's Ames Vertical Gun Range is going to help astronauts who plan to live on the lunar surface for extended periods of time--NASA's shooting for six months. Meteoroid impacts are especially powerful on the Moon since it doesn't have the atmosphere to retard their descent.