The northern slope of this unnamed crater in Arabia Terra exhibits light- and dark-toned slope streaks that are common on Mars.

Most scientists believe that slope streaks are formed by the downslope movement of very dry, fine-grained dust, similar to an avalanche on Earth. Darker slope streaks are thought to be younger than lighter slope streaks.

This image shows a unique dark streak that split around a knob sticking out from the crater wall and then joined back together downslope.
Written by: Jennifer Griffes

All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible: Image: NASA/JPL/University of Arizona

For information about NASA and agency programs on the Web, visit: http://www.nasa.gov. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems is the prime contractor for the project and built the spacecraft. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona. The image data were processed using the U.S. Geological Survey’s ISIS3 software.