NASA scientists said on Friday they were testing a prototype of a robot the US space agency hopes to send to Mars in 2020 in Chile's Atacama desert.
NASA hopes to use this kind of rover to explore life-friendly sites found by Curiosity, the rover already searching for signs of life on Mars. It has been there since last August.
The researchers say the desert, the driest spot on Earth, mimics the conditions of the Red Planet, and the agency has used it in the past to test space-bound equipment.
The robot, controlled remotely from the US, will continue testing through Sunday.
The solar-powered 771-kilogram (1,700-pound) machine is equipped with cameras and a drill able to dig up to a meter (three feet) deep.
It is testing its sensors, its cameras, its ability to store energy, as it searches for evidence of microbial life in the desert.