video transcript

Its developers call it a hedgehog. The robot is covered by spikes, but unlike the those of its namesake, they're not for protection against predators, but against the dangers of unknown terrain on the Martian moon Phobos. Issa Nesnas, a robotics engineer from NASA's Jet Propulsion Laboratory, says Phobos is shrouded in mystery. He says scientists want to find out how it came to orbit its planet closer than any other in the solar system. (SOUNDBITE) (English) ISSA NESNAS, ROBOTICS ENGINEER, JPL, SAYING: "Exploring the Martian moon of Phobos gives us more information about the origins of that moon which helps us understand more about the solar system." And the hedgehogs are key to that understanding. They will be part of an autonomous system, that also comprises a mother ship equipped with a suite of sensors to scan the moons' surface and then deploy several of the spiky robots for a closer look. Stanford's Marco Pavone says what makes the mission difficult is the lack of gravity. (SOUNDBITE) (English) MARCO PAVONE, ASSOCIATE PROFESSOR OF ASTRONAUTICS, STANFORD UNIVERSITY, SAYING: "We all know about the Mars Rovers and they are very successful at what they do on Mars. But Mars has a gravity level that is comparable to the one on Earth." Phobos however, has almost no gravity to speak of. Pavone says a robot with wheels would be impossible to control and would most likely drift off the surface into space. He says the hedgehog's spikes will give the robot more traction. For propulsion, the team is developing a set of internal flywheels to generate force. (SOUNDBITE) (English) MARCO PAVONE, ASSOCIATE PROFESSOR OF ASTRONAUTICS, STANFORD UNIVERSITY, SAYING: "By spinning and accelerating these internal wheels we are able to generate a torque on the Rover which gives rise to reaction forces from the terrain. It makes the Rover hop or tumble." (SOUNDBITE) (English) ISSA NESNAS, ROBOTICS ENGINEER, JPL, SAYING: "Our hope is that the next step is taking this platform to what we call the vomit comet which is a zero-g airplane that allows us to have maybe 10 to 20 seconds of microgravity where we can test some of these strategies in that environment." Pavone says data the hedgehogs collect will be uploaded to the mother ship -- which would then send it back to researchers on Earth. That data, Nesnas says, could pave the way for future manned missions to Mars. Phobos's micro gravity environment would be safer and cheaper to land humans on than Mars itself. He also says the moon's close orbit to the planet will give astronauts the ability to control more sophisticated exploration vehicles on Martian surface in near real time. The researchers say it will take several years to complete the development of the probes and their mother ship, but, they say, unravelling the mysteries of Phobos - and other mysteries of the solar system - is well within reach.