This observation shows a small crater in within the much larger Pollack Crater containing light-toned material. Pollack Crater is a 90-kilometer diameter impact crater first imaged by the Mariner 9 spacecraft.
This material was first observed by the THEMIS team, and there are multiple Context Camera and Mars Orbiter Camera images showing that this light-toned material may be similar to the large “White Rock” outcrop to the northwest. HiRISE has also imaged White Rock several times . In these cases, we can see how different teams can work together to get an interesting image at high resolution for further study.
Written by: HIRISE Science Team (audio by Tre Gibbs) (21 August 2013)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_018212_1715
Image: NASA/JPL/University of Arizona