Explanation:
Water has been discovered on the surface of the Moon.
No lakes have been found, but rather NASA's
Moon Mineralogy Mapper aboard India's new
Chandrayaan-1lunar orbiter radios back that parts of the Moon's surface absorb a very specific color of light identified previously only with water.
Currently, scientists are trying to fit this with other facts about the
Moon to figure out how much water is there, and even what form this water takes.
Unfortunately, even the
dampest scenarios leave our moon dryer than the
driest of Earth's deserts.
A fascinating clue being debated is whether the
water signal rises and falls during a single lunar day.
If true, the signal might be explainable by hydrogen flowing
out from the Sun and interacting with
oxygen in the lunar soil.
This could leave an extremely thin
monolayer
of water, perhaps only a few molecules thick.
Some of the resulting water might subsequently evaporate away in bright sunlight.
Pictured above, the area near a crater on the
far side of the Moon shows a
relatively high abundance of water-carrying minerals in false-color blue.
Next week, the new LCROSS satellite will release an
impactor that will strike a
permanently shadowed crater
near the lunar south pole to see if any hidden water or ice sprays free there.
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