NASA has been conducting several tests for the past three years in search of evidence of life on Mars. But, they are not conducting the experiments on the red planet. Their ‘Martian surface’ is situated in Chile.

Due to its extreme dryness, the Atacama Desert in Chile is one of the most important environments on Earth for researchers who need to approximate the conditions of Mars.

Working in 90-plus-degree heat in arguably the driest place on Earth, the team behind NASA’s Atacama Rover Astrobiology Drilling Studies (ARADS) is testing out a drill that can go 2 m deep and operate autonomously with minimal human guidance. Probing that far down below the harsh Martian surface will reveal a world we have never seen up close before - one where scientists believe there’s a chance for life.

What is the purpose of the project?

Each year from 2016 to 2019, the ARADS team, led by Brian Glass of NASA’s Ames Research Center, in California’s Silicon Valley, has been spending one month working in the heart of the Atacama.

This alien landscape is among the driest places on Earth; it can rain as little as 1 cm per decade here. Despite being considerably warmer than Mars, the region is remarkably similar to the Red Planet today, due to its extreme dryness and soil chemistry.

ARADS aims to show that roving, drilling and life-detection can all happen together, with the goal of demonstrating the technical feasibility and scientific value of a mission that searches for evidence of life on Mars.

The drill, developed in partnership with Honeybee Robotics, is attached to a rover carrying a suite of instruments. These tools can analyse the soil samples dug up by the rover and discover potential biosignatures of microbial life.

Crucial for Mars 2020

ARADS is an important demonstration of NASA’s readiness to one day take these technologies to Mars on other missions beyond the upcoming Mars 2020.

“ARADS is all about preparing NASA to search for life on Mars,” said Glass. “Developing the science instruments and robotics we will need is a big part of that, and so is figuring out how we actually run the mission. The best way to practice that is to go and do it here on Earth.”

As NASA’s Artemis programme prepares to return humans to the moon by 2024, the agency has its longer term sights on Mars. Decades of robotic missions to Mars have shown that billions of years ago, Mars likely had oceans of water and a denser atmosphere - conditions that could have supported life.

The Mars 2020 rover mission is part of NASA’s Mars Exploration Programme, a long-term effort of robotic exploration of the Red Planet. The Mars 2020 mission addresses high-priority science goals for Mars exploration, including key questions about the potential for life on Mars. The mission takes the next step by not only seeking signs of habitable conditions on Mars in the ancient past, but also searching for signs of past microbial life itself.

Today, Mars’ surface is incredibly dry - with a thousand times less water than the driest parts of the Atacama. Glass and his team of engineers and scientists have travelled to the Atacama for the past four years to develop the capability to detect the remains of ancient life, or life that’s somehow eking out an existence underground.

This final deployment of the rover in the Atacama will test out its ability to conduct this complex science across the vast distance between Earth and Mars. A team of scientists are remaining at NASA Ames to operate a “mission control” room where they will analyse results from afar and then tell the rover where in the desert to dig. To pull this off, not only does NASA need a drill that can dig deeply, it needs to dig smartly.

What are the specialities of the rover prototype?

At the center of the ARADS project is an Ames-designed and developed rover prototype that is about the same size as the Spirit and Opportunity rovers on Mars.

Called K-REX2, it is equipped with a drill capable of reaching 2 m down through salt, rock layers and parched soil to retrieve a sample for analysis.

When given a target destination, the rover can navigate autonomously over a rugged, Mars-like surface, then drill and transfer samples to the onboard scientific instruments automatically.

The mobility (provided by the rover) plus access below the surface (offered by the drill) means ARADS can test different strategies for searching for potential evidence of life in three dimensions.

Testing the operations of the rover and drilling system in a Mars-like environment will help researchers prepare for future missions to Mars, including choosing the best locations to explore and engineering systems for set-up and stabilization of the drill - all on a planet with less than half the gravity of Earth.