Enchanced-color traverse section of Martian icy scarps in late spring to early summer. Arrows indicate locations where relatively blue material is particularly close to the surface. Image taken by HiRISE camera on Mars Reconnaissance Orbiter. (NASA/JPL/UNIVERSITY OF ARIZONA/USGS )


Huge escarpments of quite pure water ice have been found in the Southern Highlands of Mars — accessible enough that astronauts might some day be able to turn the ice into water, hydrogen and oxygen.

Some of these deposits are more than 100 meters thick and begin only a meter or two below the surface.

These are among the conclusion from a new paper in the journal Science that describes these previously unknown water ice reserves.  While Mars scientists have long theorized the presence of subsurface ice under one-third of the planet, and even exposed bits of it with the Phoenix lander, the consensus view was that Martian ice was generally cemented with soil to form a kind of permafrost.

But the “scarp” ice described by Colin Dundas of the U.S. Geological Survey and colleagues is largely water ice without much other material.  This relative purity, along with its accessibility, would make the ice potentially far more useful to future astronauts.

“The ice exposed by the scarps likely originated as snow that transformed into massive ice sheets, now preserved beneath less than 1 to 2 meters of dry and ice-cemented dust or regolith,” the authors write. The shallow depths, the write “make the ice sheets potentially accessible to future exploration.”


The bright red regions contain water ice, as determined by measurements by the High-Resolution Imaging Science Experiment (HiRISE) on NASA’s Mars Reconnaissance Oribter. (NASA)


The importance is clear:  These sites are “very exciting” for potential human bases as well, says Angel Abbud-Madrid, director of the Center for Space Resources at the Colorado School of Mines in Golden, who led a recent NASA study exploring potential landing sites for astronauts.

Water is a crucial resource for astronauts, because it could be combined with carbon dioxide, the main ingredient in Mars’s atmosphere, to create oxygen to breathe and methane, a rocket propellant. And although researchers suspected the subsurface glaciers existed, they would only be a useful resource if they were no more than a few meters below the surface. The ice cliffs promise abundant, accessible ice, Abbud-Madrid told Science Magazine.

While the discovery adds to the view that Mars is neither bone-dry now nor was earlier in its history, it does not necessarily add to the question of where all the Martian water has gone or how much was originally there.… Read more