May 4, 2015
A piece of Mars: The surface in this 960×540 m (0.6×0.34 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 […]
April 29, 2015
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, 480×270 m (0.3×0.17 mi) in size. These beasts moved from right to left across […]
April 19, 2015
A piece of Mars: This 300×300 m (984×984 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 […]
April 10, 2015
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 […]
March 18, 2015
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 600×450 m (0.37×0.28 mi) […]
March 9, 2015
A piece of Mars: Ripples form endless chevrons in this 600×450 m (0.37×0.30 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 […]
February 17, 2015
A piece of Mars: Most dunes on Mars are dark, like these and these. So why is this one bright? It’s adjacent to a more typical, dark dune. It’s possible that there are two populations of sand here that are […]
February 9, 2015
A piece of Mars: The smooth areas are eroded dunes, separated by fields of boulders (the scene is 1.51×1.14 km or 0.93×0.71 mi). The largest boulder near the center is 7.5 m (25 ft) across, the size of a small […]
February 2, 2015
A piece of Mars: What happens to dunes as they move over rough terrain? This is what a barchan looks like on a relatively flat surface. If the hills are smaller than the dune, then it does its best to […]