Possible Mud Volcanoes on Mars
This HiRISE image shows a flat plain with various low, lumpy mounds. Some of them have distinct colors and tones unlike the surrounding plains, suggesting that they are made up of a different type of material.
While the origin of these mounds is not certain, one idea that seems to fit best is that they are deposits left after eruptions of wet sediments onto the surface. This can happen when thick deposits of wet sand and mud are shaken, say from a meteorite impact, and the ground briefly loses its strength, allowing dirty water to be expelled from the deposit. On Earth, this process of "liquefaction" can happen during earthquakes.
If this hypothesis is correct, it means that these mounds provide samples of a potentially habitable environment that we would otherwise need massive drills to reach.
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. (The original image scale is 30.7 centimeters [12.1 inches] per pixel [with 1 x 1 binning]; objects on the order of 92 centimeters [36.2 inches] across are resolved.) North is up.
This is a stereo pair with ESP_071528_2245.
The University of Arizona, in Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., in Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.