Robot snakes on Mars? Serpentine probe could explore Red Planet.

Last month, fans of the Curiosity rover’s images spotted something unusual in one of its snapshots from Mars: a rat.

Now, the European Space Agency (ESA) is sending something to the planet to take care of the problem: a snake.

Well, sort of. There is no rat – it’s a rock – but the ESA is, in fact, hoping to put a (robotic) snake on the Red Planet.

A Norwegian institute, Stiftelsen for Industriell og Teknisk Forskning (SINTEF), is collaborating with the ESA to develop a new, snake-shaped robot that will slither on Mars, collecting details from the hard-to-reach places that the four rovers that have so far successfully visited the planet have been unable to access.

The Curiosity and Opportunity rovers, even while filing back to Earth unprecedented amounts of information about Mars, are limited in what they can do and where they can go, the SINTEF scientists say. That’s because these rovers have wheels; and wheels, as any backroads driver knows, are liable to sticking.

That point was all too clear in the spring of 2009, when the Spirit rover became stuck in soft, Martian soil. Two year later, in March 2011, NASA gave up on trying to resuscitate the rover, after some 1,300 commands sent to the craft elicited no response.

"The vehicles just cannot get to many of the places from which samples have to be taken,” the project scientists, Pål Liljebäck and Aksel Transeth, said, in a SINTEF release.

A “snake,” though, would be able to do and see things that a six-wheeled rover cannot do or see. In a video, the snake, called Wheeko glides through an emptied room, debuting as a fast, dexterous animal probing its environment at the ground-level for information. Made of ten connected round metal parts, and with a camera for a snout, Wheeko might look more like a benign caterpillar than a snake, were it not for its exaggerated “S” shape movements.

The serpentine robot is not expected to replace the rover; it’s designed to be one of its arms. The snake, the scientists say, would be a peculiarly-jointed appendage that is able to dislodge itself from the rover and slither off on its own. The snake, slipping into small crevices that its parent rover otherwise wouldn’t be able to access, would remain tethered via power cable to the rover, juicing up on its power source, the scientists said.

That’s right – if the idea of a loose, metal snake was not already worrisome enough, what we now have is a severed, independent-minded appendage that doubles as a snake.

Of course, unless you are planning a trip to Mars, this is not something you need to worry about.

The plan, though it sounds a bit like a curious hybrid of the 2006 film “Snakes on a Plane” and the Doctor Who episode, “Dinosaurs on a Spaceship,” is in fact grounded in some serious nonfictional scientific precedent. Animals have for years been proposed as inspiration for robotic prototypes. Snakes, in particular, are the model for a roster of robotics project developing versatile robots that will be deployed in search and rescue missions.