Mars: Gullies and Dunes

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  • NASA/JPL/University of Arizona

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  • NASA/JPL/University of Arizona

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  • NASA/JPL/University of Arizona

More great snapshots of Mars taken by the UA Lunar and Planetary Lab's HiRISE camera aboard the Mars Reconnaissance Orbiter. Zilair Crater? The dunes of Aonia Terra? Who names these places, Edgar Rice Burroughs?

The first shot features gullies at the edge of Hale Crater. Shane Byrne explains:

Several years ago gullies carved into hill-slopes and the walls of impact craters like the ones pictured here were discovered. Scientists are excited to study these features because, on Earth, they usually form through the action of liquid water - long thought to be absent on the Martian surface. Whether gullies form under today's cold dry conditions is a major question that planetary scientists are trying to answer.

The gullies pictured here are great examples of what a typical Martian gully looks like. You can see wide V-shaped channels running downhill