MGS MOC Release No. MOC2-490, 21 September 2003

The lower half of this June 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows an array of ridges arranged in a somewhat polygonal pattern. These ridges are being exhumed from within a blanket of material that covers the region south (toward the bottom) of this image. The origin of the ridges is not known; they might, for example, have started out as cracks and joints in the overlying material that became filled with coarser or cemented material that was left standing as solid ridges when the overlying sediment was eroded away. This picture is located near 11.0°N, 147.8°W, and covers an area 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.