Snowbound on the Dunes
Icy Martian dunes contain mysterious dark streaks in this south polar image taken by the Mars Reconnaissance Orbiter (MRO).
The frost is likely an accumulation of frozen water and carbon dioxide ice. But the small, dark streaks might have resulted from avalanches of sand or patches of coarse-grained ice clear enough for the dark material below the ice to become visible. The streaks, running thousands of feet long, follow the local topographical patterns of the Martian landscape and do not appear to have a chaotic pattern of distribution. They are likely related to the dark spots scattered throughout the image, which could have resulted from ice evaporation leaving behind dust formerly contained in the ice.
The site for the image was chosen by astronomy students from Budapest, Hungary, through a NASA program that invites the public to help select imaging targets on Mars.
–NASA/JPL-Caltech/UofA/High-Resolution Imaging Science Experiment and SPACE.com Staff
Credit: NASA/JPL-Caltech/UofA/High-Resolution Imaging Science Experiment