Original URL: http://www.theregister.co.uk/2011/11/16/mars_windy/

Boffins reckon Mars quite blustery actually

Shifting sand dunes caused by wind, not carbon dioxide frost

By Brid-Aine Parnell

Posted in Science, 16th November 2011 15:21 GMT

A new geophysical study of Mars' sand dunes has claimed that the Red Planet may be a windy place after all, despite the evidence of previous experiments.

The shifting red sands of the planet have up till now been attributed to carbon dioxide ice sublimation, since boffins believed that strong winds weren't a possibility in the current Martian climate.

Researchers trying to figure out how the dunes on Mars moved around have previously conducted wind tunnel and atmospheric computer simulations that seemed to suggest that the planet wasn't a very blustery place. They concluded that the sands must move about because of carbon dioxide frost instead.

But in a new study, published in the Geophysical Research Letters (GRL), boffins from the SETI Institute, the University of Coimbra in Portugal and the US Geological Survey focused their attention on dune movement in the Arabia Terra and Meridiani region of Mars, which are not affected by seasonal changes in carbon dioxide ice.

Using images for the High Resolution Science Experiment (HiRISE) camera on the Mars Reconaissance Orbiter, NASA's water-seeking satellite, and other sources of information, they measured the sands merrily blowing along by 0.4m to 1m (1.3 to 3.3ft) per Martian year.

"The study shows clear evidence that wind-driven dune activity occurs regularly on Mars today," the American Geophysical Union, publisher of GRL, said. "This suggests that carbon dioxide ice sublimation is not necessary for Martian sand movement, as had previously been thought, and that wind tunnel measurements and computer simulations showing that strong winds are rare on Mars need to be reconsidered." ®