This picture of sand dunes in Wirtz Crater was obtained by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in early October 2002. The shape of the dunes indicates that wind has been transporting the sand from the southwest toward the northeast (lower left toward upper right). The picture covers an area about 3 km (1.9 mi) wide and is located near 48.6°S, 25.5°W. Sunlight illuminates the scene from the upper left.