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Birthday · November 18, 2009

Water Discovered in Moon Shadow

November 18, 2009

On the day you were born, the universe did what it has always done best: transformed chaos into beauty.

Water Discovered in Moon Shadow

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APOD published November 18, 2009. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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Water Discovered in Moon Shadow

Original APOD · November 18, 2009

Why is there water on the Moon? Last month, the LCROSS mission crashed a large impactor into a permanently shadowed crater near the Moon's South Pole. A plume of dust rose that was visible to the satellite, although hard to discern from Earth. The plume is shown above in visible light. Last week, the results of a preliminary chemical analysis gave a clear indication that the dust plume contained water. Such water is of importance not only for understanding the history of the Moon, but as a possible reservoir for future astronauts trying to live on the Moon for long periods. The source of the lunar water is now a topic of debate. Possible origins include many small meteorites, a comet, or primordial moon soil.

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