yardangs

July 13, 2017

Experimenting with 3D views

A Piece of Mars: I often use JMARS to visualize Mars data sets, especially images. They’ve recently updated their 3D layer, allowing folks to make lovely vistas by overlaying DTMs with images. I’m new at this, but I’ll experiment and […]
March 14, 2017

Windblown or not? Probably…

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 […]
January 16, 2017

Dunes carving up rock (3D)

A Piece of Mars: Get out your 3D blue/red glasses (or look here for a 2D version if you can’t find them). This is a 3.2×1.8 km (2×1.13 mi) scene showing dark dunes carving lanes 50-70 m (165-230 ft) deep […]
October 31, 2016

On Mars the wind carves stream channels

A Piece of Mars: This 1.6×2 km (1×1.24 mi) scene mostly shows what wind will do to fine-grained, weakly-consolidated surfaces. It has created topography that further strengthens wind scour in the hollows, which even leave kilometers-long grooves reminiscent of water-carved […]
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 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 […]
June 27, 2016

How to hide geology on Mars

A Piece of Mars: Three things are trying to hide in this 0.96×0.48 km (0.6×0.3 mi) scene. 1) Craters are slowly being both scoured and buried by migrating sand, 2) the sand itself is hiding in the lee of crater […]
February 20, 2016

It’s a rock-eat-rock world

A Piece of Mars: This 738 x 415 m (0.46 x 0.26 mi) scene shows dark sand flowing down a channel bisected by a ~60 m (~200 ft) tall, thin “island”. That island, and many others around it (see the […]
December 30, 2015

That which curves and that which is straight

A Piece of Mars: The long meandering lines snaking across the image (3.2×1.8 km or 2×1.1 mi across) are inverted channels. They are river deposits that once were the lowest part of the landscape (rivers always are), but then the […]