Recurring Slope Lineae (called “RSL”) are seasonally-repeating dark flows that are active at the warmest times of the year. Some of these grow from the top of the steep slope downwards as expected for liquid or granular flows.
Others show different darkening patterns, which suggests different processes. Although HiRISE has acquired many images to monitor RSL sites, it still is not certain how these features form.
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 25.8 centimeters (10.2 inches) per pixel (with 2 x 2 binning); objects on the order of 51.7 centimeters (20.4 inches) across are resolved.] North is up.
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. 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.
Image credit: NASA/JPL-Caltech/Univ. of Arizona