February 19, 2013

Drifting sand

A piece of Mars: Dark sand has been blown into the scene from the upper right. It has piled up against older, brighter dunes that may now be inactive. The sand drifts on and on, piling up where the wind […]
February 12, 2013

Mars’ giant amphitheater

A piece of Mars: Sandwiched between hills, a huge stepped amphitheater has been carved out of the rock by the wind. The scene is 770×577 m across, with each giant step about 20 m wide. Just imagine a huge concert […]
February 10, 2013

Rainbow dunes on Mars

A piece of Mars: The dark dune here seems to have a subtle rainbow color across it. Is it a real rainbow? Well, no. Part of it is that I’ve stretched the image to enhance color, so the dark dune […]
February 3, 2013

Dunes being buried

A piece of Mars: Most dunes on Mars are the freshest, youngest features around. Not so here. The bright dunes near the bottom here are slowly being buried by debris coming down from the gullies on the slope, coming from […]
February 1, 2013

Dunes. Just dunes.

A piece of Mars: These large dunes are located in Kaiser crater, a big crater in the southern midlatitudes. The scene is 789×592 m across. Imagine standing on one of these monsters, and seeing nothing but pristine ripples criscrossing all […]
January 21, 2013

Circles

A piece of Mars: What are those dark, flat circles and why are there little dunes sitting on top of them? They’re probably old impact craters that got filled in with dark sediment, and were then eroded flat. So you’re […]
January 11, 2013

Bright and dark sand on a dune

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 […]
January 8, 2013

Mysterious textures

A piece of Mars: Dunes don’t usually have a rough surface texture like these do. It’s not clear what’s going on. Are they ancient dunes that are being eroded? What causes this particular texture? It seems unique to high elevations […]
December 31, 2012

Dune cannibals

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 […]