Strange surface features sprawled around the bases of steep slopes on Mars point to the presence of ice on the planet's surface, according to new data and imagery from NASA's Mars Reconnaissance Orbiter (MRO).
Deposits of rock and sediment around these slopes are either ice-rich now or were sometime in the past, but "the source of the ice is unclear," NASA officials said in a statement. "There is some thought that it is deposited from the atmosphere during periods of high obliquity, also known as axial tilt."
Characteristics like these are common around the planet's mid-latitudes and tend to appear near gullies, or small ravines that have been worn away by the flow of water. These regions are typically also accompanied by tall, rocky ridges called moraines, which form in glacial regions and look like icy piles of soil and rock. [Latest Photos from NASA's Mars Reconnaissance Orbiter]
Viscous flow features and steep slopes are especially huge in this composite, which was taken by MRO's High Resolution Imaging Science Experiment (HiRISE), one of six high-resolution imaging science instruments on MRO. You can view the entire, high-resolution image in 3D here.