Taken at 3:44 p.m. local Mars time in January 2011, the photograph above shows "portions of the Martian surface in unprecedented detail," according to NASA. It was shot from the High Resolution Imaging Science Experiment (HiRISE) camera mounted on NASA's Mars Reconnaissance Orbiter.
The ridges seen in the photograph are between three and 33 feet wide. Running across the Hellas impact basin, the largest known impact crater in the Solar System, some of the larger ridges, known as Mars channels, or gullies, would be referred to as ravines if they existed here on Earth.
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