Posted by tourdemars to Planetology at November 15, 2005 02:41 PM

From the shoreline of an ancient salty sea to the bottoms of deep, flood-carved channels, Mars is scarred with geological signs that indicate liquid water once flowed on the its surface. These findings, combined with the discovery of tiny, spherical "blueberries" and the detection of water ice in the planet's polar ice caps, have lead scientists to scour the planet for liquid water in recent years. The elusive quarry has remained hidden, possibly because it may not exist for more than a fleeting second. Due to Mars' low temperatures and extremely low atmospheric pressure – less than a hundredth that of the Earth– pure water evaporates from ice to gas so quickly that it skips the liquid phase. But now, new research by a team of scientists at the University of Arkansas suggests that liquid water could persist for some time on Mars, so long as it is salty.