• West-facing impact crater in Mars’ northern hemisphere

    Date:12 June 2013 Tags:, , , , ,

    This image shows the west-facing side of an impact crater in the mid-latitudes of Mars’ northern hemisphere. The High Resolution Imaging Science Experiment (HiRISE) camera on Nasa’s Mars Reconnaissance Orbiter took the image on 13 April 2010.

    Like many mid-latitude Martian craters, this one has gullies along its walls that are composed of alcoves, channels and debris aprons. The origins of these gullies have been the subject of much debate; they could have been formed by flowing water, liquid carbon dioxide or dry granular flows. The orientation of these gullies is of interest because many craters contain gullies only on certain walls, such as those that are pole-facing. This could be due to changes in orbital conditions affecting long-term climate cycles and differences in solar heating along specific walls.

    Many of the other features observed in and around this crater are indicative of an ice-rich terrain, which may lend credence to the water formation hypothesis for these gullies.

    This image spans a distance of about 1,2 kilometres and is presented in false colour, which aids in distinguishing among surface materials and textures.

    Image credit: Nasa/JPL-Caltech/University of Arizona