Mars Atmosphere Fights Back!

HiRISE and the Context Camera (CTX, also on board the Mars Reconnaissance Orbiter) are always on the lookout for new impact craters. New impacts can be identified by comparing images of the same region taken at different times (typically years apart) and looking for visual clues of recent impacts.

CTX is more adept at identifying new impacts because of its larger and repeated surface coverage, but HiRISE allows us to study those impacts in higher resolution. In this image, we can see multiple dark spots corresponding to numerous new craters. We can also identify a slightly larger crater, and a number of smaller ones, particularly in a cluster next to it. That clustering gives us the first indication that these craters were formed in a single event.

As the impactor was falling towards Mars, the friction with the atmosphere led to the body fragmenting into smaller pieces shortly before striking the surface creating this notable pattern.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. (The original image scale is 26.9 centimeters [10.6 inches] per pixel [with 1 x 1 binning]; objects on the order of 81 centimeters [31.9 inches] across are resolved.) North is up.

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.