If, a couple of decades ago, you'd bet that scientists would one day tell us that there's a lot of water on the Moon, the odds are you'd be rich now.
For many decades, the Moon had been considered one of the driest worlds around. But in recent years, orbiting spacecraft have found strong evidence of water all over the Moon -- either bound with minerals at the surface, or mixed with the soil as ice. And in some places, there may be great slabs of ice just waiting for someone with an icepick to come chip away at it.
The water is basically found in three forms.
One form, detected in samples brought back by Apollo astronauts, is water that was created with the Moon. This water is locked up in the rocks beneath the lunar crust.
The second is molecules of water or a related compound, called hydroxyl, that are bound to minerals at the lunar surface. Orbiting satellites have detected this form of water all across the lunar surface.
And the third form is ice crystals that are hidden in craters at the lunar poles that never see the Sun. A craft that slammed into a crater near the south pole last year found that ice made up more than five percent of the surface material. And another craft found that there could be hundreds of millions of tons of ice around the north pole. So it's a sure bet that you wouldn't have to look very hard to find water on the surface of the Moon.
We'll talk about a moon with even more water tomorrow.
Script by Damond Benningfield, Copyright 2010
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