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Swiss Cheese and Dust Devils: 7 High-Resolution Shots of Surface Activity on Mars [Slide Show]

The Red Planet is frigid and possibly sterile, but its surface still sees plenty of action

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The arrival of NASA’s Mars Reconnaissance Orbiter (MRO) at the Red Planet in 2006 ushered in a whole new era of Mars observation. With its ultrapowerful HiRISE camera, the orbiter has spied on the Martian surface to study curious features, some of them possibly linked to the presence of water, in unprecedented detail. And along the way HiRISE has also uncovered a few new phenomena.

At the top of that list are recurring slope lineae (RSL), which HiRISE scientists discovered in 2011. RSL are dark lines that appear during the warm season on southern slopes, spread gradually downward and then fade as the weather turns cold again. The behavior of RSL suggests that they are caused by flows of briny liquid water, which, if confirmed, would stir new hopes for current life on Mars.

Click here for a slide show of some of Mars’s most interesting surface features, including animated gifs of recurring slope lineae growing and fading from one season to the next, as documented from orbit by the HiRISE camera.

»View the Slide Show

The Long and Arduous Quest to Find Flowing Water on Mars May Be Over

John Matson is a former reporter and editor for Scientific American who has written extensively about astronomy and physics.

More by John Matson
Scientific American Magazine Vol 308 Issue 5This article was published with the title “Swiss Cheese and Dust Devils: 7 High-Resolution Shots of Surface Activity on Mars [Slide Show]” in Scientific American Magazine Vol. 308 No. 5 ()
doi:10.1038/scientificamerican052013-2M39MTXWTLObSd60TEymgN

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