Lines in the Sand

Credit: NASA/JPL/Uni­ver­sity of Ari­zona

Swirls in the dust mark out lines in the sand where dust dev­ils play along the ridges in the high lat­i­tudes of Mars in this image from NASA’s HiRISE camera.

Explore the hills, gul­lies and dune fields within this image. What shapes and sto­ries does your imag­i­na­tion cre­ate? Share your sto­ries below.

Wind, sand and dust play a huge role in shap­ing the sur­face of Mars. The dark swirls dom­i­nat­ing this land­scape show the paths of dust dev­ils. Dust dev­ils occur on Earth too. These strong, well-formed whirl­winds are like mini-tornadoes. They are ver­ti­cally rotat­ing columns of air formed when warm air at the sur­face punches through cooler air above. The col­umn of air may begin to rotate. When it does, more warm air is sucked in from the sur­round­ing area giv­ing it more power. The sur­round­ing cooler air con­tains the spin­ning col­umn of warm. On Mars, spin­ning dust dev­ils pick up the fine dust leav­ing darker sand behind show­ing the swirling paths. Sand and dust also fill in craters and other shal­low areas through­out this image.