Sand dunes in a vast area of northern Mars long thought to be frozen in time are changing with both sudden and gradual motions, according to research using images from a NASA orbiter.
These dune fields cover an area the size of Texas in a band around the planet at the edge of Mars’ north polar cap. The new findings suggest they are among the most active landscapes on Mars. However, few changes in these dark-toned dunes had been detected before a campaign of repeated imaging by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter, which reached Mars five years ago next month. (more…)