SPILLWAY. Looking upstream in Ares Vallis, the broad channel almost disappears into the scenery, despite being roughly 100 kilometers (60 miles) wide here. At left center, a partly destroyed crater named Oraibi stands at the head of a mid-channel island, streamlined into a teardrop shape by the floodwaters. The lack of a narrow meandering channel, such as is found in many large terrestrial rivers, suggests the floods here were massive but brief. The vertical exaggeration is 1.5x. Click on the image for a higher-resolution (432K) version.

Image credit: NASA/JPL/Arizona State University, R. Luk