ripples

February 2, 2015

Dunes ignoring small hills

A piece of Mars: What happens to dunes as they move over rough terrain? This is what a barchan looks like on a relatively flat surface. If the hills are smaller than the dune, then it does its best to […]
January 26, 2015

On Mars, the wind wins

A piece of Mars: This scene (600×450 m or 1969×1476 ft) is covered in small craters, formed by the splash of a larger crater nearby. They cover everything, even the bright ripples visible on the right. So the ripples were […]
January 21, 2015

Wind eroded mantle

A piece of Mars: The curving ridge of a mountain has signs of many small landslides. Mantled on top of these is an older set of landslides that has been partially eroded away. The rippled edge of this older deposit […]
January 12, 2015

Bearded craters and dunes

A piece of Mars: This 600×450 m (1969×1476 ft) scene has a complex sedimentary history. How are bearded craters and dunes formed? They weren’t always bearded. At some point, a deposit of bright material accumulated on this surface, and was […]
January 5, 2015

The long, low dune

A piece of Mars: A long, low dune covered in long, linear ripples stretches across the scene (600×450 m; 1969×1476 ft). Dark gray areas on the dune show where sand has most recently moved. A small slip face has formed […]
December 19, 2014

Wind, wind, impact(!), and then more wind…

A piece of Mars: Some time ago, something hit the ground on Mars and made this impact crater, right into a field of ripples. Stuff thrown up during the impact fell back down, burying the ripples with the gray ejecta […]
December 8, 2014

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 […]
November 25, 2014

Panda stripe dustslides

A piece of Mars: This 600×450 m (1969×1476 ft) scene of a hillside shows new, dark dustslides that slid downhill (to the lower left). Faint stripes of older dustslides are visible, covered by bright dust and small ripples. Thousands of […]
November 17, 2014

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 […]