HiRISE: Impact crater in Isidis Planitia

This recent observation is the fifth time we’ve imaged this spot on Mars. We often re-image spots on the surface to search for, or track changes, due to active processes, such as migrating sand dunes. In this case, there isn’t any known activity, although careful comparison of the images could show changes. Instead, we acquired these pictures at a range of viewing and illumination angles as an experiment to try to extract new information at the limits of image resolution… [More at link]