dunes
February 10, 2014
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
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
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
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
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
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
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 […]
July 8, 2013
A piece of Mars: The blue structures are rippled dunes found not far from the south polar cap of Mars. They are probably partially active, enough to create the fine ripples found on and between the dunes. But the steeper […]
May 21, 2013
A piece of Mars: Swirly loops form on the martian surface as dust devils pass by, cleaning up dust on the surface and revealing the dark, rippled dune beneath. Every year the swirls get cleaned off and reform — such […]