MGS MOC Release No. MOC2-338, 22 April 2003
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image was taken during southern spring, as the seasonal carbon dioxide frost cap was subliming away. Frost remaining in shallow cracks and depressions reveals a fantastic polygonal pattern. Similar polygons occur in the Earth's arctic and antarctic regions-on Earth such polygons are related to the freeze and thaw of ground ice. The picture covers an area about 3 km (about 1.9 mi) wide near 71.9°S, 11.1°W. Sunlight illuminates the scene from the left.