dunes

March 10, 2014

Lighting effects

A piece of Mars: It’s winter in the southern hemisphere, and dunes like these are covered in bright white CO2 frost. The sun is near the horizon (shining from the top of the image), so it creates stark shadows. That […]
March 5, 2014

Swoosh

A piece of Mars: What is this big swoosh? It’s a big dark dune. The dark/light striping across it is found in all of the dunes in this area, but what is it? We’re probably seeing the inside of the […]
February 10, 2014

Yes, this is a bit of windy Mars. Really.

A piece of Mars: Yep, this is really Mars. It’s a tiny bit (600×450 m) of the southwestern side of a large dune in the southern midlatitudes. The dark lines are furrows that are thought to be carved by blocks […]
January 16, 2014

Lines, lines

A piece of Mars: On martian dunes it’s all about lines, lines, lines. The prominent wavy ones on the left are thought to be erosional scars left by sliding blocks of dry ice. The little fingerprint-like lines are ripples, like […]
December 27, 2013

Wintery dune

A piece of Mars: A single dune sits on the surface of Mars, not too far from the north pole. It’s early spring, but this far north the dune is still covered in white CO2 frost (as well as a […]
October 25, 2013

Are you being oblique?

A piece of Mars: Barchan, or crescent dunes, are generally thought to form from winds blowing from a single direction. Reality isn’t usually that nice. Here are two barchans with crescent-shaped slip faces on their eastern (right) sides, indicating that […]
September 30, 2013

Waiting for spring

A piece of Mars: These sharp-tipped hills are dunes near the north pole of Mars. At the height of summer they’re lovely dark dunes, but because it’s just barely spring here they’re still covered in white frost (mostly CO2 ice, […]
September 4, 2013

Martian sports

A piece of Mars: In the center are two dark dunes, racing one another to jump over hurdles formed of older, now inactive dunes (or maybe those bright things are ripples, we still don’t know for sure). The dune in […]
August 21, 2013

Natural modern art on Mars

A piece of Mars: Abstract modern art? No, these are north polar dunes almost completely covered in winter frost (mostly CO2 ice). It’s early spring in this image, and the dark sand underneath the ice is only just beginning to […]