These Spidery 'Veins' On Mars Are Just Plain Weird (Photo)
This photo, captured by NASA's Mars Reconnaissance Orbiter in February 2009, shows spidery troughs on the Red Planet likely formed by the sublimation of carbon dioxide.
Credit: NASA/JPL-Caltech/University of Arizona

Nobody knows yet whether or not Mars has ever hosted life, but the Red Planet itself looks strangely alive in a newly released NASA photo.

Slender, branching troughs snake across a pinkish, pitted swathe of the southern hemisphere of Mars in the image, creating an impression (at least to this observer) of blood vessels forking through flesh.

The photo was taken by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO) on Feb. 4 2009, but the agency featured it online on Monday (Jan. 11). You can see more awesome Mars photos by MRO here.

The complex terrain shown in the image was likely shaped by the sublimation (transition from solid phase to gas) of the seasonal carbon-dioxide ice cap near Mars' south pole, NASA officials said.

"The troughs are believed to be formed by gas flowing beneath the seasonal ice to openings where the gas escapes, carrying along dust from the surface below," NASA officials wrote in a description of the photo Monday. "The dust falls to the surface of the ice in fan-shaped deposits."

The HiRISE image depicts an area 0.6 miles (1 kilometer) wide that lies nearly 82 degrees south of the Martian equator. The photo was captured during springtime in the Red Planet's southern reaches. 

No planet is more steeped in myth and misconception than Mars. This quiz will reveal how much you really know about some of the goofiest claims about the red planet.
The original 'Face on Mars' image taken by NASA's Viking 1 orbiter, in grey scale, on July, 25 1976. Image shows a remnant massif located in the Cydonia region.
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Mars Myths & Misconceptions: Quiz
No planet is more steeped in myth and misconception than Mars. This quiz will reveal how much you really know about some of the goofiest claims about the red planet.
The original 'Face on Mars' image taken by NASA's Viking 1 orbiter, in grey scale, on July, 25 1976. Image shows a remnant massif located in the Cydonia region.
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"The image was taken at a local Mars time of 4:56 p.m., and the scene is illuminated from the west with a solar incidence angle of 78 degrees; thus the sun was about 12 degrees above the horizon," NASA officials added in the description.

MRO launched in August 2005 and reached Mars the following March. For the past nine-plus years, the spacecraft has searched for signs of past and present water activity on the Red Planet, scouted out possible landing sites for future crewed and robotic missions and relayed communications from surface craft such as NASA's Curiosity and Opportunity rovers, among other work.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.