Frosty dunes
Small dunes on Mars
June 1, 2015Dust devils and wind scours on ripples on dunes
July 27, 2015
A piece of Mars: In this image (0.96×0.54 km or 0.6×0.33 mi), it’s late winter and the sun is barely above the horizon here near the north pole. The dunes are covered in winter frost, most of which is CO2 ice (also known as dry ice). The dark regions are those facing the sun, where the ice has started to sublimate, revealing the dark sand below. (HiRISE ESP_041433_2650, NASA/JPL/Univ. of Arizona)
