This image was originally meant to track the movement of sand dunes near the North Pole of Mars, but what's on the ground in between the dunes is just as interesting!

The ground has parallel dark and light stripes from upper left to lower right in this area. In the dark stripes, we see piles of boulders at regular intervals.

What organized these boulders into neatly-spaced piles? In the Arctic back on Earth, rocks can be organized by a process called "frost heave." With frost heave, repeatedly freezing and thawing of the ground can bring rocks to the surface and organize them into piles, stripes, or even circles.

On Earth, one of these temperature cycles takes a year, but on Mars it might be connected to changes in the planet's orbit around the Sun that take much longer.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 32 centimeters (12.6 inches) per pixel (with 1 x 1 binning); objects on the order of 96 centimeters (37.8 inches) across are resolved.] North is up.

This is a stereo pair with ESP_053937_2550.

Related Links
Mars Reconnaissance Orbiter
Mars News and Information at MarsDaily.com
Lunar Dreams and more

Tweet

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

Nearly a Decade After Mars Phoenix Landed, Another Look
Pasadena CA (JPL) Feb 22, 2018
A recent view from Mars orbit of the site where NASA's Phoenix Mars mission landed on far-northern Mars nearly a decade ago shows that dust has covered some marks of the landing. The Phoenix lander itself, plus its back shell and parachute, are still visible in the image taken Dec. 21, 2017, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. But an animated-blink comparison with an image from about two months after the May 25, 2008, landi ... read more