January

January 27, 2014

Ancient and slightly less ancient

A piece of Mars: Here are two craters, each of which is ~240 m across. On the right is an old, very eroded crater. It has old, eroded ripples on its floor. The crater on the left is younger, with […]
January 24, 2014

Little dunes that Curiosity saw last October

A piece of Mars: On Oct. 15, 2013, Curiosity drove past a crater that has small dunes or ripples on its floor. In a new HiRISE image, you can see Curiosity’s tracks from that day (its 424th sol on Mars). […]
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 […]
January 13, 2014

Mars’ fleets of rock “boats”

A piece of Mars: Where the wind blows strong and there’s a lot of sand, the surface gets scoured. Some bits of the ground, called yardangs, are more resistant and stick around: they take on shapes elongated in the direction […]
January 8, 2014

Bearded hills

A Piece of Mars: Bright hills appear to be bearded (or perhaps mustached?). What’s going on? Dark sand has blown over some yellow-crested hills and settled on the downwind side, where the hill blocks enough wind that it can no […]