Posted: Thu, May 30, 2002, 10:18 AM ET (1418 GMT)
Data from NASA's Mars Odyssey spacecraft have revealed "enormous quantities" of water ice hidden just below the surface in polar regions of the Red Planet. The discovery, to be published in Friday's issue of the journal Science, was officially acknowledged by NASA on Tuesday after several days of speculation in the media. The neutron spectrometer on Mars Odyssey had detected the telltale signature of hydrogen, and thus most likely water, about 30 to 60 centimeters below the surface from 60 degrees south latitude down to the south pole. When combined with data from the spacecraft's gamma-ray spectrometer, scientists concluded that the ice is located in a layer with concentrations in excess of 50 percent by volume. The total amount of water there is estimated to be twice the volume of Lake Michigan. Scientists will be watching the north polar region of Mars over the next several months as summer returns to that hemisphere and melts the seasonal dry-ice polar cap. The results augment a preliminary finding from Mars Odyssey back in March that suggested that the planet may have more water ice than expected. The news was widely expected after the online publication SpaceRef first reported last week comments by a NASA official that suggested that an announcement about a water ice discovery was forthcoming.

Related Links:

•  NASA press release
•  Sky and Telescope article
•  SPACE.com article
•  New Scientist article
•  Reuters article