Lunar ice reveals moon's poles shifted

In 2009, NASA’s LCROSS mission sent a rocket crashing into a crater near the moon’s south pole, sending debris into space and confirming earlier indications of the presence of water ice on the moon. In a new study, researchers have found that the distribution of ice around the lunar poles doesn’t quite match what scientists initially expected. Instead of ice deposits centered only on the present-day poles — the darkest, coldest spots on the modern moon — ice appears to also be concentrated several degrees away from either pole. And, these off-axis deposits are directly across from one another, or antipodal, on opposite sides of the moon. The reason for this, the study’s authors say, is that the moon, shortly after its formation, shifted off its original rotation axis, causing new ice deposits to form around the new poles while older ice deposits remained at the original poles.

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Lucas Joel

Lucas Joel was EARTH's 2015 summer intern.

Joel (www.lvjwriting.com) is a freelance science journalist. He has a master's in paleontology from the University of California, Riverside, and is currently based in Boulder, Colo. 

Tuesday, July 26, 2016 - 06:00