aeolian
June 19, 2017
A Piece of Mars: The real tetrahedrons of Mars are dunes, built by winds blowing sand from more than one direction. This 0.5×0.5 km (0.31×0.31 mi) area shows a dune formed from two winds that are about 90 degrees apart: […]
June 5, 2017
A Piece of Mars: Having a bad day? You’re in good company with these dunes in this 0.96×0.48 km (0.6×0.3 mi) scene. The gray barchanoid dunes are covered in ripples, as the wind valiantly tries to push the sand to […]
March 27, 2017
A Piece of Mars: Sand pours in from the top of this 1.95×1.95 km (1.21×1.21 mi) scene. The sand piles up and up (here ~115 m or 377 ft high), but ahead (at the bottom) is a mountain poking up. […]
March 20, 2017
A Piece of Mars: In a recent post (Dunes in a Colorful Hole), I showed some dunes crawling over layered terrain, with a view that looked a lot like some desert regions of Earth. Here’s another spot on Mars (0.95×1.1 […]
March 14, 2017
A Piece of Mars: This 0.95×0.95 km (0.59×0.59 mi) scene shows an eroding surface punctured by some old craters. Long, thin lines seem to form in the wake of many brighter knobs. Are those thin lines windblown in origin? They […]
March 8, 2017
A Piece of Mars: A fluid is something that fills a container it’s put into, and it includes both gas and liquids. This 0.7×0.5 km (0.43×0.31 mi) scene shows hills of sediment left behind by two different fluids (wind and […]
February 21, 2017
A Piece of Mars: This is the crest of one of the largest dunes on Mars (0.5×0.5 km or 0.31×0.31 mi). The wind mostly blows from the right, slowly pushing sand up the windward slope. But frost accumulates on (and […]
February 13, 2017
A Piece of Mars: Is this 480×270 m (0.3×0.17 mi) scene showing a 150 m (492 ft) wide yin-yang symbol on Mars? Sort of, maybe, if you blur your eyes and lend me artistic license, but it’s not doing so […]
December 19, 2016
A Piece of Mars: A low, broad dune occupies the center of this 800×450 m (0.5×0.28 mi) scene, blown by a dominant wind towards the lower left. The slip face on the lee side has several small avalanches, formed as […]
December 12, 2016
A Piece of Mars: Higher ground is to the left. You’re seeing a tan layer sandwiched between two gray layers in this 0.96×0.54 km (0.6×0.34 mi) scene. Large ripples have accumulated in the lowest area to the right, which is […]
November 21, 2016
A Piece of Mars: Dunes and ripples most commonly form in topographic lows. But not in this 0.96×0.54 km (0.6×0.34 mi) scene. Here, and in other places on Mars, these bedforms (called TARs) form on plains, and sometimes appear to […]
November 7, 2016
A Piece of Mars: Wind from the upper left is blowing dark dunes toward the lower right in this 1.92×1.08 km (1.19×0.67 mi) anaglyph (if you don’t have your red/blue 3D glasses handy, you can also check out the black […]