Atacama Rover Astrobiology Drilling Studies (ARADS)
(26 February 2018 - NASA Ames) How would you search for signs of life – traces of tiny, living microbes or their fossilized remains – in an extreme and distant environment? NASA scientists and engineers are working on an answer to that question, aiming to find out if life ever evolved on the planet Mars and if it still harbors life today.
ARADS rover in the Atacama (courtesy: NASA Ames)
A project called the Atacama Rover Astrobiology Drilling Studies, or ARADS, has been designing tools and techniques for future exploration and testing them in one of the most Mars-like places on Earth: Chile’s Atacama Desert.
Each year from 2016 to 2019, the ARADS team, led by Brian Glass of NASA’s Ames Research Center, in California’s Silicon Valley, is 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 one centimeter, or less than half an inch, 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.
Long ago, Mars was a more temperate place. Scientists believe its climate was warmer and wetter, and the planet was surrounded by a magnetic field that protected it from the blast of radiation coming from the Sun. Conditions might possibly have been favorable for the development of life. The surface of Mars today is much harsher: ultra-dry, cold and with little protection from the Sun’s ultraviolet radiation. If life did exist on Mars in the past, as surface conditions changed it may have been driven underground. So, we may have to dig to find its traces today.
ARADS team members Dean Bergman and Mary Beth Wilhelm, at NASA's Ames Research Center, prepare to test the drill installed on the K-REX2 rover before beginning field tests in Chile's Atacama Desert. The large pot holds a mix of soils with known properties that approximates a type of soil on Mars. The team will test the drill's ability to cut into this material and retrieve a sample. (courtesy: NASA/Ames Research Center/Dominic Hart)
Searching in Three Dimensions with a Drilling Rover
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 already on Mars. Called K-REX2, it is equipped with a drill capable of reaching two meters (6.5 feet) 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 K-REX2 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.
The sample retrieved from below ground by the rover's drill is automatically transferred into the metal scoop at the end of the long, blue robotic arm. The soil is then passed through the funnels on the rover's top platform to several life-detection instruments below that will analyze its contents. NASA and its partners are developing tools and techniques for future exploration of Mars and testing them in Chile's Mars-like desert. (courtesy: NASA/Ames Research Center/Dominic Hart)
ARADS’ Life-detection Instruments
Additionally, other ARADS team members from Johns Hopkins University and Ames have been collecting samples for laboratory studies of the extreme microorganisms living inside salt habitats in the Atacama. These salt habitats could be the last refuge for life in this extremely dry region that is otherwise devoid of plants, animals and most types of microorganisms. What scientists learn about these resilient organisms could help improve life-detection technology and strategies for Mars.
Ultimately, the ARADS project aims to show that roving, drilling and life detection can take place in concert, with the goal of demonstrating the technical feasibility and scientific value of a mission that searches for evidence of life on Mars.
Partners on the Atacama Rover and Drilling Studies include several NASA centers – Ames Research Center in California’s Silicon Valley, Goddard Space Flight Center in Greenbelt, Maryland, and the Jet Propulsion Laboratory in Pasadena, California – as well as Johns Hopkins University in Baltimore, Maryland, Honeybee Robotics in New York, the University of Antofagasta and CampoAlto SpA, both in Chile, and Spain’s Center for Astrobiology.