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Buried glaciers found on Mars
(Agencies)
Updated: 2008-11-21 08:18
Mars has vast glaciers hidden under aprons of rocky debris near mid-latitude mountains, a new study confirms, pointing to a new and large potential reservoir of life-supporting water on the planet. These mounds of ice exist at much lower latitudes than any ice previously found on the red planet. "Altogether, these glaciers almost certainly represent the largest reservoir of water ice on Mars that's not in the polar caps," said John Holt of the University of Texas at Austin and the main author of the study. "Just one of the features we examined is three times larger than the city of Los Angeles and up to one-half-mile thick, and there are many more." The gently sloping mid-latitude debris flows have puzzled scientists since they were revealed by NASA's Viking orbiters in the 1970s -- they looked very different than the fans and cones of debris found near mountains and cliffs in Mars' equatorial regions. Since their discovery, scientists have been debating how the features formed, with some proposing they were debris flows lubricated by ice that had since evaporated away. But more recent observations suggested that the features "might be more ice than rock," Holt said. In other words, they could be Martian glaciers. Holt and his colleagues used radar observations of the features, taken by NASA's Mars Reconnaissance Orbiter (MRO), to peer into the features. The findings, detailed in the Nov. 21 issue of the journal Science, suggest that the glacier theory is correct. Finding huge deposits of ice at the Martian mid-latitudes is a boon to both the study of past potential Martian habitability, as well as future human exploration. Glaciers are huge reservoirs of water once they melt, key to all life as we know it. |
