August

August 29, 2016

Where does the windblown stuff come from?

A Piece of Mars: How far do windblown materials move on Mars? This scene (0.9×1.2 km, 0.56×0.75 mi) shows a bright layer of bedrock (top right) that is eroding, exposing a darker, bluish rock (bottom left). Ripples 5-20 m wide […]
August 22, 2016

Erosional remnants

A Piece of Mars: The erosionally-streamlined bright areas are on high ground. They are remnants of a vast dusty mantle that once covered this whole area – the rest of it has been blown away. The surrounding regions (check out […]
August 15, 2016

Ancient ripples?

A Piece of Mars: Potential signs of wind activity are everywhere on Mars. Take this 0.96×0.54 km (0.6×0.34 mi) scene, which is on bedrock dated to be several billion years old. There’s a fabric of ridges trending from the upper […]
August 8, 2016

Fossil dunes

A Piece of Mars: This 1.92×1.08 km (1.19x 0.67 mi) scene shows eroded ridges that are, in fact, lithified dunes. They are so old that you might not recognize them as dunes without more context. This doesn’t happen much on […]
August 1, 2016

Dunes not in the global dune database

A Piece of Mars: Ten years ago I participated in a global survey of martian dunes. But we missed a few dune fields, like these beauties. They’re small, low, and in rugged terrain, which made them difficult to spot in […]