Lunar Dust

StarDate: July 18, 2009

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The Moon anchors a beautiful display in the wee hours of tomorrow morning. The planet Venus is a little to the right of the Moon; it's the brilliant "morning star." The true star Aldebaran is about the same distance to the right of Venus, with the planet Mars directly above Aldebaran. Mars and Aldebaran are both orange, and they're about the same brightness, so they form an eye-catching pair.

You can't tell just by looking, but the Moon is a dusty place. When the first astronauts walked on the Moon 40 years ago this month, their boots and legs were quickly coated with dust.

ARMSTRONG: The surface is fine and powdery. I can kick it up loosely with my toe. It does adhere in fine layers, like powdered charcoal, to the sole and sides of my boot. [:20]

In part, that's because the dust consists of jagged little bits of glass and metal -- particles ground up by a constant "rain" of microscopic meteorites on the lunar surface.

But the dust is also sticky because it has an electric charge. When radiation and particles from the Sun hit the lunar surface, they give the tiny dust grains an electric charge. At times, that can cause the smaller grains to hover above the surface -- sometimes hundreds of feet.

A recent study says that the effect should be worst during the middle of the lunar day. So future explorers may need to take a long lunch break to get away from the sticky lunar dust.

Script by Damond Benningfield, Copyright 2009

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