Tag Archives: slip face

Tortoise and hare

A Piece of Mars: There's a lot of evidence for both fast and slow movement in this 480x270 m (0.3x0.17 mi) scene. The tortoise: The rippled surface at the top is high ground: the top of a dune. Wind pushes ...

The trail of a dune

A Piece of Mars: A low, broad dune occupies the center of this 800x450 m (0.5x0.28 mi) scene, blown by a dominant wind towards the lower left. The slip face on the lee side has several small avalanches, formed as ...

Grainfall

A Piece of Mars: The dunes climbing over a rocky surface in this 0.96x0.54 km (0.6x0.34 mi) scene are mostly yellow because they're covered (and therefore kept immobile) by dust. The crest of one dune, though, shows recent activity: dark ...

Light and dark

A Piece of Mars: This 0.96x0.54 km (0.6x0.34 mi) late winter scene is a study in contrast. The dark top half is uniformly rippled. This is the shady surface of the main windward side of one of Mars' biggest dunes, ...

Curiosity about sand dunes (part 2/2)

Today is December 21, 2015 (northern winter and southern summer solstice on Earth). On Mars it is Ls = 84ยบ, Mars Year 33 (about 12 sols from northern summer and southern winter solstice on Mars). It is sol 1200 of ...

Stealth bomber dunes

A piece of Mars: These dunes look strangely triangular, a little bit like a flock of stealth bombers. Why? They're two-faced barchans. Each flat face is an avalanche slope that faces downwind, formed by one of two distinct wind patterns ...

The looming dune

A piece of Mars: this 0.96x0.54 km (0.6x0.33 mi) scene shows a large, rippled dune that is slowly marching towards the upper right. The smooth striped band running from upper left to lower right is the slip face, where sand ...