This is an especially pretty image due to the color variations and lighting geometry.
The color variations are due to mixtures of reddish dust with white frost and ice. The image was acquired as a “rider” with either a Context Camera or CRISM target.
One of these other MRO experiments chose this location to point at with the spacecraft, then the HiRISE science lead for this 2-week planning cycle decided to add a HiRISE image here for a high-resolution sample.
Written by: Alfred McEwen (15 February 2012)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_025715_2605
Image: NASA/JPL/University of Arizona