spacetoday.net: LRO detects evidence for water ice in lunar crater

Posted: Thu, Jun 21, 2012, 7:09 AM ET (1109 GMT)
Shackleton crater topographic map (NASA/MIT)

Data from a NASA orbiter suggests that water ice is present in at least minute amounts on the floor of a crater at the Moon's south pole, scientists reported Wednesday. In a paper published in the journal Nature, scientists using the laser altimeter on NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft concluded that 22 percent of the material in a micron-think layer on the floor of Shackleton crater consists of water ice. Scientists had previously suspected that the crater, more than 20 kilometers across and 3 kilometers deep, harbored ice based on its brightness. The same analysis also found that the crater's walls were even brighter than the floor, a surprising finding since ice would be unlikely to accumulate along the crater walls. Scientists cautioned that some or all the brightness on the crater floor detected in the LRO observations could be caused by differences in the brightness of lunar regolith linked to seismic activity.