Friday, April 11, 2008

Wonder why they didn't mention GCR's?

Lunar surface charging and electric fields caused by sunlight and solar wind. Credit: Jasper Halekas and Greg Delory of U.C. Berkeley, and Bill Farrell and Tim Stubbs of the Goddard Space Flight Center. [Larger image]

NASA Moondust is dry, desiccated stuff, and may seem like a dull topic to write about. Indeed, you could search a ton of moondust without finding a single molecule of water, so it could make for a pretty "dry" story. But like the dust in your mother's attic, moondust covers something interesting – the moon – and even the dust itself has curious tales to tell.

A group of NASA and University of Alabama researchers are what you might call "active listeners": Mian Abbas, James Spann, Richard Hoover and Dragana Tankosic have been shooting moondust with electrons, levitating moondust using electric fields, and scrutinizing moondust under an electron microscope. All this is happening at the National Space Science and Technology Center's "Dusty Plasma Lab" in Huntsville,

"Moondust was a real nuisance for Apollo astronauts," adds Abbas. "It stuck to everything – spacesuits, equipment, instruments." The sharp-edged grains scratched faceplates, clogged joints, blackened surfaces and made dials all but unreadable. "The troublesome clinginess had a lot to do with moondust's electrostatic charge."

Dust on the moon is electrified, at least in part, by exposure to the solar wind. Earth is protected from the solar wind by our planet's magnetic field, but the moon has no global magnetic field to ward off charged particles from the sun. Free electrons in the solar wind interact with grains of moondust and, in effect, "charge them up."

Read more HERE.