New dust devils swirls
Dunes on crater bones
May 2, 2013Where does martian sand come from?
May 24, 2013
A piece of Mars: Swirly loops form on the martian surface as dust devils pass by, cleaning up dust on the surface and revealing the dark, rippled dune beneath. Every year the swirls get cleaned off and reform — such patterns are known to occur in only a few select places on Earth, but they are common on Mars. (HiRISE ESP_031199_2070, NASA/JPL/University of Arizona)
