NASA this month began testing a prototype robot in the Chilean desert, as part of the agency's ongoing search for evidence of life on Mars. The prototype, known as Zoë, is a solar-powered, autonomous robot equipped with onboard sensors, cameras, and a one-meter drill. The robot will use its drill to find and analyze soil samples from Chile's Atacama Desert, the driest on Earth. Led by Carnegie Mellon University and the SETI Institute, the Life in the Atacama Project was launched earlier this month as NASA began testing a variety of new technologies that could be used on the craft that replaces the Curiosity rover in 2020.

Zoë is explicitly designed to search for signs of microbial life, which experts say would likely exist well below the Martian surface. "Direct evidence of life, if it exists, is more likely underground, beyond the current reach of rovers," David Wettergreen, research professor at Carnegie Mellon's Robotics Institute, said in a statement earlier this month. "Chances improve with greater depth but we are first developing one-meter capability and integrating with a mobile robot."

The search for life continues

Researchers chose the Atacama Desert because its dry conditions mimic those observed on Mars. Controlled remotely by researchers in the US, Zoë began its tour of the desert on June 17th, and will conclude testing on Sunday. Unlike previous field tests, in which researchers focused on the robot's autonomous capabilities, this trial has focused on Zoë's ability to gather and analyze samples.

"Now, we think of the robot as a tool to collect specific data from specific locations, rather than as a machine that drives around," Wettergreen said.