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From late 2013 to early 2014,
a NASA mission called LADEE

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explored the Moon's
tenuous atmosphere and its dust

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environment.

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Now, LADEE's observations
have led to a new discovery: the

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lunar surface is
periodically releasing water.

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What we discovered is that the
surface releases its water when

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the Moon is bombarded
by micrometeoroids.

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This is especially noticeable
during meteor showers.

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What we also found is that the
surface that's releasing the

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water is being protected by a
layer, a few centimeters of dry

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soil that can only be breached
by large micrometeoroids.

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When micrometeoroids impact the
surface of the Moon, most of the

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material in the
crater is vaporized.

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There is also a shock wave
that propagates outward.

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That shock wave carries enough
energy to release the water

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that's coating the
grains of the soil.

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Most of that water will get
released into space, and that's

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the signature that LADEE detects
with its instrument from its

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orbit.

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By analyzing the data
returned by the neutral mass

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spectrometer, we found that the
intensity and the frequencies of

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the fluctuations of signals
from the water to be perfectly

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correlated with
known meteor streams.

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For example, we were able to
detect a big spike of water

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during the Geminid meteor shower
that occurred in December of

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2013.

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Thanks to LADEE, we now know
that trace amounts of water are

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widely distributed
across the lunar surface.

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This discovery provides a
potential resource for future

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exploration, and it improves
our understanding the Moon's

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geologic past and its
continued evolution.

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[Music]