dunes
January 11, 2013
A piece of Mars: A lovely little dune is right at the edge of this image, trying its best to migrate into the center of the frame. The bright sickle-shaped part of the dune is its slip face, where sand […]
December 31, 2012
A piece of Mars: Dunes often cannibalize each other, with new dunes forming from the sand in older dunes. Here the tan dunes have formed from the sand that made up the grayish blue dunes. Notice the banding on the […]
December 16, 2012
A piece of Mars: These wispy dunes look like veins on a leaf, don’t they? The thicker ones are older, and they are slowly being reworked by the younger, thinner ones. If they remain active, then the smaller ones will […]
December 6, 2012
A piece of Mars: A lonely dune slowly makes its way (towards the upper right) across a plain. Well, look closer, it’s not all that lonely. Surrounding it on the plain are smaller streaks that are ripples, which also once […]
November 25, 2012
A piece of Mars: Small dunes (or possibly ripples) are likely no longer moving in today’s winds. Or are they? Dark splotches on their upper (northern) sides suggest some kind of wind scour has recently occurred. Winds blow, create dunes, […]
November 12, 2012
A Piece of Mars: A large dune (on the right, bluish) rests on a surface covered in much smaller dunes or ripples (on the left, cream). This is part of my favorite dune field on Mars. Can you spot the […]
August 24, 2012
A piece of Gale crater, Mars: Here are some of the large, dark dunes not far from where Curiosity has landed. They’re pretty big monsters, 200-300 meters across. Their shape indicates they’ve been formed from two different wind directions: one […]
August 3, 2012
A piece of Mars: Compare this with my post five days ago and you might think the scenes are similar. In fact they’re not. In the previous case sedimentary layers were carved out by the wind, leaving behind swirly patterns […]
July 30, 2012
A piece of Mars: Bright dunes once marched through the depression created by a double impact. How can you tell the dunes are no longer moving? Because one of them has its own little crater sitting on it. A mobile […]