spacetoday.net: Study: lunar interior dry

Posted: Fri, Aug 6, 2010, 8:32 AM ET (1232 GMT)
A new study finds that, in contrast to earlier work, the interior of the Moon is effectively dry. A team at the University of New Mexico studied lunar samples returned by the Apollo missions, measuring the ratio of chlorine isotopes as a means of measuring how much water the rocks contained when they were formed billions of years ago. They found a wide range of results, which they said can be best explained if the lunar interior has very little water: as little as 1/100,000th as the Earth's interior. The results stand in contrast with some other recent studies that suggested the lunar interior had considerably more water. The finding is separate from other analyses that have detected water ice on or near the lunar surface, particularly in polar regions; that ice is deposited from comet impacts well after the Moon formed.