A rover designed for a future mission to search for signs of life on Mars was tested recently in Chile’s Atacama Desert, a location considered the driest place on Earth.
The site makes a good stand-in for Mars because of its scarcity of water and regular exposure to ultraviolet solar radiation.
Based on soil content and geological evidence, scientists believe this area has been extremely dry for 10 to 15 million years or longer.
One difference is that with temperatures around 90 degrees Fahrenheit, the desert is notably warmer than any place on Mars.
Last month, a team of 35 scientists, researchers, engineers, and support staff tested a rover and scientific instruments designed to probe beneath the Martian surface for signs of microbial life as part of NASA’s four-year Atacama River Astrobiology Drilling Studies (ARADS) program.
The second in a series of equipment tests, this particular effort was conducted to illustrate that roving, drilling, and searching for signs of life can be done by one vehicle at the same time.
Because the Atacama Desert is so dry, any life in the region would likely have migrated underground. The same is true for Mars, where microbial life if it does exist, is likely located beneath the surface and/or within rocks.
Equipment tested include a KREX-2 rover that carries a lightweight, low-power drill, and a robotic transfer arm. Three life-detection instruments near the rover fed the arm with samples captured by the drill.
The life-detection instruments included the Wet Chemistry Laboratory designed by NASA’s Jet Propulsion Laboratory (JPL), which had been placed on the 2007 Phoenix Mars Lander, and the Signs of Life Detector, an instrument that uses biochemical methods similar to those used in medical tests to look for 512 biological compounds, built by Spain’s Center for Astrobiology.
Both instruments were used in ARADS tests conducted in 2016.
A new science instrument, the Microfluidic Life Analyzer, also built by JPL, isolates amino acids from tiny liquid samples.
The rover successfully drilled to a depth of 6.5 feet (two meters), capturing samples for study by the life-detection instruments. According to ARADS principal investigator Brian Glass, DNA and biomarkers for life were found in most of the samples.
“The drill, rover, and robot arm combination behaved beautifully in the field. It was a steady platform that enabled us to go deeper than we expected,” Glass said.
Next year, the life-detection instruments will actually be placed on the rover.
ARADS testing in the Atacama desert will continue through 2019.