NASA/JPL/University of Arizona
Ripples, dunes and shadows create swirling and looping patterns in this image from the HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter.
Explore the sprawling Martian dunefield. What stories and patterns do you see? Leave a note in the comments below.
Scientists use images like this one to not only study wind processes on Mars but also to look for fresh impact craters. From time to time, HiRISE takes images of the same part of the Red Planet giving scientists a chance to see what has changed between images. Scientists are not sure whether Martian dunes have evolved over thousands of years or if they are young features. Dunes in this image appear fresh and young. They have sharp crestlines (top of dunes) and active looking slipfaces (downwind slopes of dunes). Most of the dunes point toward the southwest which shows the predominant wind direction in this area. But some dunes show signs of sand being pushed back up the slope making the slopes smooth with few ripples. A quick look around the image shows that no impact craters are present. More dune fields are left to explore.
Launched with MRO in 2005, HiRISE is one of six instruments aboard the spacecraft orbiting Mars. HiRISE’s cameras can see objects on the surface as small as a beach ball. The camera also offers scientists stereo views of the surface.