This image was acquired to take a closer look at a circular feature that might be an impact structure on the South Polar layered deposits.
Measuring the sizes and frequency of impact craters provides a constraint on the age of the landscape. However, craters in icy terrain are modified by processes that flatten and change them in such a manner that it is hard to say for sure if it had an impact origin.
Written by: Alfred McEwen (audio: Tre Gibbs) (3 April 2017)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_049075_0995
Image: NASA/JPL/University of Arizona