Frost on Mars

Frost on Mars

. Atmospheric water vapor freezes onto the surface of Mars, producing a thin coating of water ice on rocks and soil. These white patches of frost were photographed from the Viking 2 lander at its Utopia Planitia landing site on 18 May 1979; the frost remained on the surface for about 100 days. (Courtesy of NASA and JPL.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University