This enhanced-color view shows gullies in an unnamed crater in the Terra Sirenum region of Mars. It is a sub-image from a larger view imaged by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter on Oct. 3, 2006. This scene is about 254 meters (about 830 feet) wide. The upper and left regions of this scene are in shadow, yet color variations are still apparent. The high signal to noise ratio of the HiRISE camera allows for colors to be distinguished in shadows. This allows dark features to be identified as true albedo features versus topographical features.