Tag Archives: ripples

Fuzzy dunes

A Piece of Mars: The dunes (or maybe they're ripples) in this valley appear to be fuzzy (the view is 625x775 m, 0.39x0.48 mi). They're not really fuzzy, but it's not actually clear what's going on. They seem to have ...

Ripples of rock

A Piece of Mars: To the upper right of this 0.85x0.6 km (0.53x0.37 mi) scene is a flat-lying plain strewn with large ripples. To the lower left is a rugged hill with gray rock laced with white veins (this might ...

The corpse of a dune

A Piece of Mars: The rippled darker patch in this 600x600 m (0.37x0.37 mi) scene is the former site of a sand dune. This is one of a few "dune corpses" found just upwind of a dune field in Holden ...

Mars’ corduory

A Piece of Mars: The wind on Mars likes to make textiles (unfortunately the term geotextiles is already taken for other purposes). This 1x0.6 km (0.62x0.37 mi) scene shows two different sets of ripples. The larger set has straight to ...

Leeward and poleward

A Piece of Mars: The sharp line in this 0.625x0.625 km (0.39x0.39 mi) scene is the crest of a long dune in Mars' southern hemisphere. The sunlit side is also the lee side: the bright streaks are thin sand avalanches ...

Wind and maybe water too

A Piece of Mars: Along the right side of this 0.5x0.5 km (0.31x0.31 mi) scene is the rim of a crater - the stripes are layers exposed (and then perhaps draped by falling ejecta) as the crater formed. To the ...

Dunes fighting for survival

A Piece of Mars: Having a bad day? You're in good company with these dunes in this 0.96x0.48 km (0.6x0.3 mi) scene. The gray barchanoid dunes are covered in ripples, as the wind valiantly tries to push the sand to ...

A change of fluids

A Piece of Mars: Water carved this ~800 m (0.5 mi) wide channel billions of years ago. The water dried up, and since then it's been sand that flows through here (from the right), building up lovely dunes. A single ...

Two directions

A Piece of Mars: Sometimes I just want to show the interior of a dune field, because it's full of waves: ripples and dune crests, slip faces, all of which signs of movement. The dunes in this 0.67x0.47 km (0.41x0.29 ...

Who wins in the fight of wind vs. ice?

A Piece of Mars: This is the crest of one of the largest dunes on Mars (0.5x0.5 km or 0.31x0.31 mi). The wind mostly blows from the right, slowly pushing sand up the windward slope. But frost accumulates on (and ...