There’s one thing I’ve always wanted to do: go ice-skating on the Moon. It’s a dream I’m sure we’ve all had at some point. The best place to make that dream become a reality is Shackleton Crater… maybe.
Shackleton Crater is a lunar cold trap situated at the Moon’s geographic south pole. The exact pinpoint location of the pole lies on the crater’s outer rim. And the inside of the crater contains water ice, or at least some scientists think so.
In the mid-1990’s, a space probe named Clementine beamed radio waves into Shackleton. The radio waves bounced back in a manner that could be interpreted as a reflection off water ice… or possibly reflections off exceptionally rough, rocky terrain.
Later, analysis of data from NASA’s Lunar Prospector and Lunar Reconaissance Orbiter revealed a higher than average concentration of hydrogen in Shackleton Crater and other nearby craters. Since hydrogen is part of the water molecule, this could be more evidence of water ice. Or it could be evidence of some other hydrogen-containing molecule.
In 2009, NASA’s LCROSS Mission made headlines for “bombing the Moon.” A large projectile crashed into Cabaeus Crater, not far from Shackleton, and the resulting debris plume was observed to contain, among other things, particles of water ice which must have lain buried underground for billions of years.
Although a lot remains open to interpretation, the pattern of evidence seems to suggest that water ice is spread throughout the Moon’s polar regions, with Shackleton Crater possibly containing one of the largest deposits.
But before we start lacing up our ice skates, we should note a few things. Any ice in Shackleton is likely buried under layers of rock, similar to what was observed in Cabaeus. Also, we might only be talking about a few hundred gallons spread thinly over an area of several hundred square kilometers.
Fortunately, my dreams of one day ice skating on Mars seem far more realistic.
The Mystery of Shackleton Crater from Air & Space.
Evidence for Water Ice near the Lunar Poles from The Journal of Geophysical Research.
An Explanation of Bright Areas Inside Shackleton Crater at Lunar South Pole Other Than Water Ice Deposits from the 2013 Lunar and Planetary Science Conference.
LCROSS Impact Data Indicates Water on Moon from NASA.
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Today’s post is part of Moon month for the 2015 Mission to the Solar System. Click here for more about this series.