Crater ejecta on Mars, satellite image. This observation examined the edge of impact ejecta from a crater to the north-west of this area (north is at top). The ejecta seen at top left appears to be lower than the surrounding surface. This is unusual and may be due to the hot ejecta falling on frozen ground and melting the underlying ice. This image was obtained in 2014 by the High Resolution Imaging Science Experiment (HiRISE) instrument on NASA's Mars Reconnaissance Orbiter (MRO) satellite.