spacetoday.net: New study raises doubts about lunar ice

Posted: Thu, Nov 13, 2003, 9:51 AM ET (1451 GMT)
Lunar south pole seen by Arecibo (Cornell Univ.)

A new study suggests that water ice may not exist in the polar regions of the Moon in the same quantities previously expected. The results, published in Thursday's issue of the journal Nature, are based on radar observations of the Moon performed by the giant Arecibo radio telescope. That research failed to detect layers of water ice at depths of up to a meter below the surface of permanently-shadowed craters in the north and south polar regions of the Moon. Bistatic radar observations by the Clementine spacecraft in 1994 and neutron spectrometer data from Lunar Prospector four years later both indicated the presence of water ice in those permanently-shadowed regions, which are thought to act as "cold traps" and protect ice. The Arecibo research doesn't rule out the presence of water ice entirely, but instead suggests it may be widely scattered within the dust layers, akin to permafrost on Earth.