Sand Dunes Near the North Pole

This picture was taken during the Martian summer with only small patches of ice remaining at the surface; they show up as bright, somewhat blue, spots on slopes that provide some shading from the Sun.

Geologists would classify these dunes as "sand-starved" because the ground between the dunes has almost no sand. This surface shows a pattern of cracks that is typical of the permafrost's seasonal expansion and contraction. It is also possible that this subsurface ice exists inside the dunes. If so, the dunes are not currently moving and are being "stabilized" by this ice.

Image credit: NASA/JPL-Caltech/University of Arizona