Mars Sandy Surface is More Dynamic Than Previously Thought

Images from NASA‘s Mars Reconnaissance Orbiter show sand dunes and ripples moving across the surface of Mars at dozens of locations and shifting up to several yards. These observations reveal the planet’s sandy surface is more dynamic than previously thought. According to Matthew Golombek, a co-author of the new paper and a member of the Mars Exploration Rover and Mars Reconnaissance Orbiter teams at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., sand moves by hopping from place to place. Not all of the sand on Mars is blowing in the wind. The study also identifies several areas where the bed forms did not move. According to scientists, the seemingly stationary areas might move  on  much  larger  time  scales,  triggered  by 

climate cycles on Mars that last tens of thousands of years. The tilt of Mars’ axis relative to its orbital plane can vary dramatically. Mars may once have been warm enough that the carbon dioxide now frozen in the polar ice caps could have been free to form a thicker atmosphere, leading to stronger winds capable of transporting sand.
source:www.nasa.gov