In this image, we see an approximately 500-meter crater that is fairly fresh (in geological terms), but the ejecta is already high-standing. Could this be an indication of early stage of pedestal development?
A pedestal crater is when the ejecta from an impact settles around the new crater and is more erosion-resistant than the surrounding terrain. Over time, the surrounding terrain erodes much faster than the ejecta; in fact, some pedestal craters are measured to be hundreds of meters above the surrounding area.
HiRISE has imaged many other pedestal craters before, and the ejecta isn’t always symmetrical, as in this observation.
This caption is based on the original science rationale.
Written by: HiRISE Science Team (audio: Tre Gibbs) (1 July 2015)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_039936_1330
Image: NASA/JPL/University of Arizona