Modified Valleys

19 January 2004
Covered by an eroded mantle of--perhaps--cemented dust, this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows part of a network of ancient valleys in northern Arabia Terra near Moreux Crater. The valleys may have originally been carved by a liquid such as water. The scene is located near 40.6°N, 316.4°W. The rugged surface of this mantled scene is a common feature at middle latitudes in both hemispheres of Mars. Some science investigators in the past several years have speculated that ice was once present in such mantles, and that the ice must have sublimed away to create the texture. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.