Tag Archives: complex wind

The real tetrahedrons of Mars

A Piece of Mars: The real tetrahedrons of Mars are dunes, built by winds blowing sand from more than one direction. This 0.5x0.5 km (0.31x0.31 mi) area shows a dune formed from two winds that are about 90 degrees apart: ...

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 ...

Mars’ giant sweaters

A Piece of Mars: Sometimes in the floors of small craters, the wind blows in from several directions to produce odd polygon-shaped dunes that look like crochet (maybe Mars is making sweaters for its craters - it is, after all, ...

Giant “combs” on Mars

A Piece of Mars: This 480x270 m (0.3x0.17 mi) scene shows a herd of 100-300 m fine-toothed combs grazing on the surface of Mars. Wait, what? No, it's not really combs. This is actually a landscape covered by two sets ...

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 ...

Crochet ripples

A Piece of Mars: This 480x270 m (1575x886 ft) area shows a seemingly endless field of ripples. They're big, about 50 m (164 ft) from crest to crest, and probably about 5 m (16 ft) high. Is there a ...

The long, low dune

A piece of Mars: A long, low dune covered in long, linear ripples stretches across the scene (600x450 m; 1969x1476 ft). Dark gray areas on the dune show where sand has most recently moved. A small slip face has formed ...

Aeolian shoreline

A piece of Mars: On the left is a steep slope leading to a hill. On the right are waves - but not waves of water or any other kind of liquid. These are dunes or very large ripples, blown ...

Textured gullies

A piece of Mars. These are gullies on a martian hillside (upslope is to the upper right). Water may be what forms the channels, carrying soil and rocks downslope. The textured pattern of the lower slope is caused by the ...

Which wind came first?

A piece of Mars: This scene (3.9x2.5 km or 2.4x1.6 mi) shows a surface carved by two different winds: one blowing from the right and one blowing from the bottom right. They've formed overlapping sets of streamlined rocks called yardangs. ...