Daedalia Planum Windstreak

Visible at the top of today's VIS image is a windstreak. The windstreak is located on Daedalia Planum, a region of extensive lava plains southwest of Arsia Mons. The dark and bright material forming the "tail" behind the crater were created by surface winds funneling over and around the crater. The raised rim and bowl of impact craters causes a complex interaction such that the wind vortex in the lee of the crater can both scour away the surface dust and deposit it back in the center of the lee. The "tail" shows the direction of the wind, in this case blowing from the right to the left.

Daedalia Planum was created by immense lava flows that originated from Arsia Mons. Arsia Mons is the southernmost of the three large aligned volcanoes in the Tharsis region. Arsia Mons' last eruption was 10s of million years ago. The different surface textures are created by differences in the lava viscosity and cooling rates. The lobate margins of each flow can be traced back to the start of each flow -- or to the point where they are covered by younger flows. Flows in Daedalia Planum can be as long as 180 km (111 miles). For comparison the longest Hawaiian lava flow is only 51 km (~31 miles) long. The total area of Daedalia Planum is 2.9 million square km – more than four times the size of Texas.