As far as locations for Mars dress rehearsals go, you could do worse than Chile's Atacama Desert. Regarded as the driest place on the planet, parts of this parched desert landscape have never seen a single drop of rain, making them largely hostile to life on Earth. Sounds a bit like Mars right? Over the month of February, NASA researchers have been using the site to test a rover equipped with scientific instruments needed to comb the Red Planet for signs of life, with a view to fine-tuning the tech ahead of future Mars missions.
The test-run is part of a four-year project called the Atacama Rover Astrobiology Drilling Studies, or ARAD. The endeavor is aimed at exploring the hypothesis that life on Mars could exist as microbial colonies underground or inside rocks. In the Atacama Desert, the water scarcity paired with constant ultraviolet radiation from the sun has driven what little life does exist there underground, and scientists believe that the same could be true of Mars.
While temperatures in the Atacama are certainly much warmer than on Mars, geological evidence suggests that the extremely dry conditions have existed there for at least 10 to 15 million years. This dryness creates soil chemistry that is remarkably similar to that of the Red Planet, giving scientists like those working on the ARAD project the perfect testing ground for life-hunting technologies.
For ARAD's first study In February 2016, more than 20 scientists from the US, Chile, Spain and France gathered at Yungay Station in the Atacama's hyperarid core. Here, facing temperatures in excess of 100 degrees Fahrenheit (38° C) and harsh winds, the team kicked things off by putting a number of technologies to the test aboard their KREX-2 rover, including a drill, an instrument for identifying microbes called the Signs of Life Detector (SOLID) and the Wet Chemistry Laboratory, which flew aboard the Phoenix Mars lander in 2007 to analyze Martian soil.
The latter two have been modified and returned to the desert this year for further trials, and were joined by a new instrument from NASA's Jet Propulsion Laboratory, the Microfluidic Life Analyzer (MILA). This so-called "Chemical Laptop" is a miniaturized laboratory that processes tiny volumes of fluid samples in search of amino acids, which are considered the building blocks of life.
The team says it was successful in its primary goal of using the rover to drill to depths of up to two meters (6.5 ft), extracting samples from the three instruments to study for signs of life, both past and present.
"The Wet Chemistry Lab saw traces of perchlorate among other soil constituents, as the Phoenix flight version found on Mars," Brian Glass, principal investigator of the ARADS project explains to New Atlas. "SOLID detected life (DNA, biomarkers) in most of the drilled samples."
Overall, MILA also performed well, reports Glass, though the team is taking a long view of the debutant and when it returns next year, a key objective will be to see if the rover can carry and operate it along with other life-detecting instruments and the drill all on its own.
"The MILA microfluidic instrument was in its very first field deployment; its objective was to process samples (which it did) while tuning its extraction techniques, so it did not generate amino acid results in the field, this year."
Testing at the Atacama site will continue through until 2019.