Most are in the martian southern hemisphere, but a few are in the north. Nearly all occur between latitudes 30 degrees and 70 degrees, and usually on slopes that get the least amount of sunlight during each Martian day. This picture shows a series of troughs and layered mesas in the Gorgonum Chaos region of the martian southern hemisphere. The presence of so many gullies associated with the same layer in each mesa suggests that this layer is particularly effective in storing and conducting water. The MOC pictures were taken on January 22, 2000.
Sunlight illuminates each scene from the upper left.
The process that starts the water flowing remains a mystery, but the team believes it is not the result of volcanic heating. Furthermore, NASA is in the process of evaluating two options for a 2003 mission to Mars, both of which could provide independent information concerning the remarkable sites identified by Malin and Edgett. In the modern climate of Mars such conditions might be only on the latitudes above 40-45 Degrees.