Driest place on Earth gives clue to life on Mars

Washington, Feb 29 (IANS) A Mars-like laboratory in the “driest place on Earth” is helping NASA scientists study the limits of life and test drilling and life-detection technologies that might be sent to Red Planet in the future.

In a harsh environment with very little water and intense ultraviolet radiation, most life in the extreme Atacama Desert in Chile exists as microbial colonies underground or inside rocks.

According to researchers at NASA, the same may be true if life exists on Mars.

The Atacama Rover Astrobiology Drilling Studies (ARADS) project has just completed its first deployment after one month of fieldwork in the hyperarid core of the Atacama Desert.

Despite being considerably warmer than Mars, the extreme dryness the soil chemistry in this region is remarkably similar to that of the Red Planet.

“Putting life-detection instruments in a difficult, Mars-analog environment will help us figure out the best ways of looking for past or current life on Mars, if it existed,” said Dr Brian Glass, NASA space scientist and principal investigator of the ARADS project.

“Having both subsurface reach and surface mobility should greatly increase the number of biomarker and life-target sites we can sample in the Atacama,” Glass added in a NASA statement.

The cold and dry conditions on Mars open the possibility that evidence for life may be found below the surface where negative effects of radiation are mitigated — in the form of organic molecules known as biomarkers.

But until humans set foot on the Red Planet, obtaining samples from below the surface of Mars will require the ability to identify a location of high probability for current or ancient life, place a drill, and control the operation robotically.

More than 20 scientists from the US, Chile, Spain and France worked in extremely dry conditions with high winds during the first ARADS field deployment.

Their work was primarily conducted at Yungay Station, a mining ghost town at one of the driest places in the Atacama, owned by the University of Antofagasta in Chile.

During this initial deployment, scientists put several technologies under harsh and unpredictable field conditions that included a Mars-prototype drill, a sample transfer arm, the Signs of Life Detector (SOLID) instrument a prototype version of the Wet Chemistry Laboratory (WCL) which flew on the Phoenix Mars mission in 2007.

Engineers and scientists were successful in using the ARADS drill and sample transfer robot arm at Yungay to acquire and feed sample material to the SOLID and WCL instruments under challenging environmental conditions.

The analyses of the drilled samples help set a yardstick for interpreting future results from these two instruments and will be compared to results obtained from the same samples in some of the best laboratories.

Additionally, researchers from Johns Hopkins University and NASA collected samples for laboratory investigations 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.

“We are excited to learn as much as we can about these distinctive, resilient microorganisms, and hope that our studies will improve life-detection technology and strategies for Mars,” noted Mary Beth Wilhelm, NASA researcher.

Over the next four years, the ARADS project will return to the Atacama to demonstrate the feasibility of integrated roving, drilling and life-detection.

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