Dust Devils on the Planet Mars
Nature…the artist. Take a look at this image of the surface of Mars. Can you guess what may have caused the gracefully arcing and curling lines? For a while, scientists were unable to untangle the mystery. Turns out that the dark tracings are caused by spinning columns of rising air – better known here on Earth as Dust Devils.
The image above was recently taken with the HiRISE camera on board the Mars Reconnaissance Orbiter. It shows dark lines “painted” onto the lighter Martian surface. If you look closely, you can even see light colored sand dunes in the upper left of the picture. The lines are caused by Martian dust devils lifting the lighter red-colored dust on the surface and exposing the darker, heavier sand underneath.
What would a Martian dust devil look like from the surface?
Back in May of this year, the Rover Spirit was lucky enough to capture one while taking exposures of the Martian surface with different colored filters. Due to the time lag between frames, you can see how the dust devils progressed across the landscape.
What’s interesting about this is how atmospheric and weather processes familiar to us here on Earth are replicated in the Martian environment. Dust devils form when the surface – heated by the sun causes the air near the surface to heat up. If conditions are right, the hot air can rise quickly through a small pocket of cooler air above it, start rotating and stretch out vertically to form a mini dust tornado or dust devil.