dunes

May 27, 2012

Tuning forks of the wind.

A piece of Mars: Small, dark ripples have overridden larger, bright ones. The larger ones have some interesting shapes — arcs, splits that resemble tuning forks, and even circles. Their shape is accentuated by the smaller, very regular ripples between […]
May 24, 2012

Fashionable stripes of Mars

A piece of Mars: Is it the latest in patterns for ties, or is it Mars? (Can it be both?) These are some unusually regular dunes on Mars, separated by a bouldered surface. The dunes have interesting pale bands common […]
May 23, 2012

At the edge

A piece of Mars: Old, subdued dunes (in blue) near the south pole on Mars. This shows the edge of a dune field, with white rock-strewn surface beyond the sand. Criss-crossing the sand are the tracks that dust devils have […]
May 22, 2012

When dunes die

A piece of Mars: This is what dunes look like when they die. At least on Mars. On Earth they typically get buried or eroded away. On Mars geology works slowly enough that the steep slopes of dunes are gradually […]
May 13, 2012

One perfect barchan on Mars

A piece of Mars: In nature most dunes pile on one another or strongly influence each other. But occasionally, like a perfect flower or crystal, you find a perfectly shaped dune. Here is a crescentic dune, called a “barchan”, formed […]
May 10, 2012

So beautiful

A piece of Mars: The dunes can be so beautiful on Mars. What a lovely vacation spot this would be, provided you brought a large supply of oxygen, food, and a heat source to keep you warm. (HiRISE ESP_026416_1620)
May 9, 2012

Sand, wind, and dust

A piece of Mars: This is what dunes look like in the deepest part of Mars, where the air is full of bright dust that constantly settles out onto everything. The wind helps to clear off the sand dunes (blue […]
May 6, 2012

High summer near the north pole of Mars

A piece of Mars: It’s high summer in the northern hemisphere of Mars. Here, dark dunes near the north pole have finally lost the seasonal ice that blankets them and turns them white for most of the year. For a […]
May 2, 2012

Mars’ moving dunes

                    A piece of Mars: Today’s image comes courtesy of my postdoc, Simone Silvestro. He’s studying migrating dunes and has made a 3 image movie of a dune moving across the […]