Category: HiRISE images

HiRISE images

Dust devils and wind scours on ripples on dunes

A piece of Mars: So much wind. There are dark swirly tracks of dust devils that have passed by, ripples covering dunes, wind scours around rocks, and of course dunes. Dune crests have a different color than other regions: are ...

Frosty dunes

A piece of Mars: In this image (0.96x0.54 km or 0.6x0.33 mi), it's late winter and the sun is barely above the horizon here near the north pole. The dunes are covered in winter frost, most of which is CO2 ...

Small dunes on Mars

A piece of Mars: These dunes are some of the smallest on Mars. The smallest in this frame is ~150 m long (492 ft). But the smallest Earth dunes are ~20 m across. Why are they so much bigger on ...

The looming dune

A piece of Mars: this 0.96x0.54 km (0.6x0.33 mi) scene shows a large, rippled dune that is slowly marching towards the upper right. The smooth striped band running from upper left to lower right is the slip face, where sand ...

Windblown or not?

A piece of Mars: The surface in this 960x540 m (0.6x0.34 mi) scene has a distinct fabric to it that runs from the upper left to lower right. Are these old lithified dunes? And what makes the tiny filamentary lines ...

Wind stripes

A piece of Mars: Yes, I post a lot of pictures of martian dunes with striped patterns. They're all distinct and beautiful. So here's another one, 480x270 m (0.3x0.17 mi) in size. These beasts moved from right to left across ...

Martian lace

A piece of Mars: This 300x300 m (984x984 ft) scene shows bright windblown dunes or ripples arrayed in a lacy pattern (the biggest ones are about 5 m, or 16 ft, across). This is near the landing site of Ares ...

Flow

A piece of Mars: Below this ~550 m (0.3 mi) wide crater lies a ~1.3 km (0.8 mi) long "beard", the wake of an ancient flow around the crater. Based on its location on Mars, I'm guessing the fluid flowing ...

Melty dunes

A Piece of Mars: With all due apologies to followers of the show Coupling, I have to call these things "melty dunes". This link shows what a crisp dune should look like. The dunes in this 600x450 m (0.37x0.28 mi) ...

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A piece of Mars: Ripples form endless chevrons in this 600x450 m (0.37x0.30 mi) scene. It's really the crest of a dune that connects all the vertices in the chevrons, making that straight line that runs nearly vertical through the ...