ice

October 1, 2019

Wind and sun on the dunes

Oct. 1, 2019 It’s spring in the northern hemisphere on Mars. Actually, as of today, it’s pretty close to northern summer solstice, but the recent crop of released HiRISE images mostly come from the spring season. Northern polar dunes on […]
August 21, 2019

Dunes or bacteria?

Aug. 21, 2019 Trolling through the HiRISE image catalog, I came across some dunes that look a bit like bacteria. (Well okay, they look like some sort of microbe to my eye, which is highly untrained in looking at microbes, […]
February 11, 2019

Why does Lori study dunes on Mars?

When I look for something to blog about, I usually go to the HiRISE catalog to see if there are any new pictures that I find interesting. Today this lovely dune field caught my eye: HiRISE images are about 6 […]
August 28, 2018

The end of winter

Richardson crater is located at 72ºS, about 1000 km (~621 miles) from the south pole of Mars. It’s a moderately large crater, about 90 km (56) miles across, and it’s mostly filled by one of the biggest dune fields in […]
July 16, 2018

Spring is a messy time

In many areas on Earth that get winter snow, spring thaw is a messy time. Frozen ground turns to mud, and there may be runoff everywhere from melting snow and spring rain. Or if you live in a place that […]
May 9, 2018

Entourage

Here’s a grand dune, making its stately way northward under winds blowing mainly from the south-southeast (bottom to top), with a secondary wind blowing from the southwest (lower left to upper right). There are two rippled and sharp-crested slip faces […]
March 1, 2018

Dune trails

There’s so much going on in this 0.75×0.75 km (0.47×0.47 mi) image. You’re looking at a broad dune migrating toward the upper right. It’s early summer, but this is close enough to the north pole that some winter ice lingers […]
January 18, 2018

Varying wind directions

A Piece of Mars: This 0.5×0.4 km (0.31×0.25 mi) scene shows two dunes near the north pole. The shape of the dunes indicates two main winds: one blowing left to right (which makes slip faces on the right side, one […]
January 8, 2018

Dunes with comet tails

A Piece of Mars: The north polar dunes in this 575×325 m (0.36×0.2 mi) scene are made of dark sand covered by bright winter frost (which will soon sublimate away, as this image was taken in late spring). To the […]