May 22, 2017

Is it an old fossil barchan dune?

A Piece of Mars: There are many barchans on Mars, those lovely isolated crescent-shaped dunes. In a few places there are what looks like ancient preserved barchans, now lithified. The mound in the center of this 0.96×0.54 km (0.6×0.33 mi) […]
May 8, 2017

Sand tails

A Piece of Mars: Up on the tallest volcanoes, the wind screams downhill at night. This 500x500m (0.31×0.31 mi) scene shows how dust is carried downhill, but only that which is trapped behind boulders and crater rims sticks around. The […]
May 1, 2017

Curiosity, recovering from the Bagnold dunes campaign

A Piece of Mars: You’ll probably want to click on this image to see the whole thing, it’s pretty big, and it’s worth seeing. This 850×550 m (0.53×0.34 mi) scene shows the barchanoid dunes of the Bagnold dune field, imperceptibly […]
April 24, 2017

The bowl of windstuff

A Piece of Mars: Get out your red and cyan glasses to see an old crater, which fills this 0.775×0.7 km (0.48×0.43 mi) scene. The crater punched through many thin layers when it formed, some of which you can still […]
April 17, 2017

A change of fluids

A Piece of Mars: Water carved this ~800 m (0.5 mi) wide channel billions of years ago. The water dried up, and since then it’s been sand that flows through here (from the right), building up lovely dunes. A single […]
April 10, 2017

Two directions

A Piece of Mars: Sometimes I just want to show the interior of a dune field, because it’s full of waves: ripples and dune crests, slip faces, all of which signs of movement. The dunes in this 0.67×0.47 km (0.41×0.29 […]
April 3, 2017

Where on Mars is this dune?

A Piece of Mars: This 0.48×0.27 km (0.3×0.17 mi) scene shows a rotund barchan dune. Can you tell from looking at it where on Mars it might be? To me the most obvious feature are the bumpy piles at the […]
March 27, 2017

A big rock in a big air stream

A Piece of Mars: Sand pours in from the top of this 1.95×1.95 km (1.21×1.21 mi) scene. The sand piles up and up (here ~115 m or 377 ft high), but ahead (at the bottom) is a mountain poking up. […]
March 20, 2017

More Earth-like views of Mars

A Piece of Mars: In a recent post (Dunes in a Colorful Hole), I showed some dunes crawling over layered terrain, with a view that looked a lot like some desert regions of Earth. Here’s another spot on Mars (0.95×1.1 […]