The image was taken on May 21 in the Northern hemisphere of Mars by the High Resolution Imaging Science Experiment (HiRISE) camera on US space agency’s Mars Reconnaissance Orbiter. Unlike on Earth, the snow and ice is carbon dioxide, better known to us as dry ice.
When the Sun starts shining on it in the spring, the ice on the smooth surface of the dune cracks and escaping gas carries dark sand out from the dune below, often creating beautiful patterns.
On the rough surface between the dunes, frost is trapped behind small sheltered ridges. NASA’s Jet Propulsion Laboratory manages the Mars Reconnaissance Orbiter, which was launched in 2005 and attained Martian orbit on March 10, 2006.