Outflow channels

Outflow channels

. A Viking 1 image of the Ares Vallis region shows dry river beds produced by past flows of liquid water. Catastrophic floods must have carved out these outflow channels deep in the Martian surface, creating streamlined hills, scoured floors, and large teardrop-shaped islands where flowing water encountered an obstacle. Ares is the Greek god of war; the Roman equivalent is Mars. (Courtesy of Michael H. Carr, U.S. Geological Survey, and NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University