lfenton

September 4, 2013

Martian sports

A piece of Mars: In the center are two dark dunes, racing one another to jump over hurdles formed of older, now inactive dunes (or maybe those bright things are ripples, we still don’t know for sure). The dune in […]
August 29, 2013

What the wind brings, the wind takes away

A piece of Mars: These C and S-shaped things were once dunes that marched across the scene (from upper left to lower right), formed from sand deposited by the wind. Then that sand somehow became cemented, locking the dunes in […]
August 21, 2013

Natural modern art on Mars

A piece of Mars: Abstract modern art? No, these are north polar dunes almost completely covered in winter frost (mostly CO2 ice). It’s early spring in this image, and the dark sand underneath the ice is only just beginning to […]
August 8, 2013

Different day, different sand

A piece of Mars: Creamy dunes (or maybe they’re very large ripples) wind their way northward between mesas. More recently darker, more mobile sand (bluish here) has piled up against the western slopes of the mesas. We don’t know why […]
July 29, 2013

Screaming winds

A piece of Mars: This image is way up high on the Tharsis Montes on Mars, at an elevation of 5900 m (19,350 ft). At night the wind comes screaming down from some of the tallest mountains in the Solar […]
July 8, 2013

South polar dunes

A piece of Mars: The blue structures are rippled dunes found not far from the south polar cap of Mars. They are probably partially active, enough to create the fine ripples found on and between the dunes. But the steeper […]
July 3, 2013

Topography

A piece of Mars: Topography makes for great landscapes. It also funnels winds, forcing dunes and ripples along particular pathways. Here a cliff (high ground is yellow) has forced low-lying, dark ripples to migrate up a slope at the end […]
June 26, 2013

Pale gold satin sand

A piece of Mars: Sand sometimes piles up on steep slopes. It forms downslope streaks as it slides downhill, which here appear like long narrow stripes, like shimmering satin (down is toward the lower left). Note the wind-blown ripples in […]
June 21, 2013

Polygons of dunes

A piece of Mars: Yep, these are dunes shaped into polygons. Each “cell” is about 25 m (~80 ft) across. The crests of these things are outlined in blue, as if somebody traced them with a pen (well it’s stretched […]