With the epic journey of NASA’s Mars rover, Curiosity, now into its second week on the Red Planet, as part of the Mars Science Laboratory (MSL) mission, you may be starting to wonder if the U.S. space agency is going to uncover the first evidence of extraterrestrial life.
But did you know that they’ve already found it?
At least that’s the claim of Gilbert Levin, who designed the soil testing experiments of one of the most ambitious Mars missions to date, the 1976 Viking program.
Those experiments included one in which a nutrient broth was added to the Martian topsoil to see if it would produce carbon dioxide – and guess what, it did on both of the two spacecraft that constituted the mission. Repeatedly.
The experiments could be interpreted as signifying that some form of life consumed the nutrient broth, causing the emissions. However, because of the complexity and well. . . alien nature of the soil chemistry, no one can be sure that this reaction was caused by microorganisms. NASA’s official position is that it was not evidence of life, and few scientists consider the test results as conclusive proof of living organisms.
So, where does the Atacama desert fit into this?
Not only does Chile’s northern desert hold some of the most sophisticated astronomical hardware on earth, it may also hold the key to unlocking soil tests like those that were undertaken by the Viking mission in the 70s, as well as those of today’s Curiosity rover.
In an article for the British newspaper, The Guardian, director of the Beyond Centre for Fundamental Concepts in Science at Arizona State University, Paul Davies, wrote that the key to establishing conclusive proof of life from soil tests could be found by studying Martian-like environments on Earth.
As the driest place on the planet, Davies posited the Atacama as the ideal place to undertake that search – and he isn’t the first.
For years, astrobiologists have been sifting the soil and sand of Northern Chile, “looking for hardy microbes able to eke out an existence in the hyper-arid terrain.”
After much research, the consensus was that nothing could survive the harsh conditions at the heart of the Atacama. Then in 2006 Jacek Wierzchos of Span’s Universidad de Lérida made a remarkable discovery.
Davies explains: Projecting out of the parched dusty surface of the desert are countless natural sculptures made of common salt. Mr. Wierzchos broke one open and was puzzled to find a distinctive dark layer inside. He dissolved the salt rock and found the colouration was caused by several new species of microbe living inside.”
That discovery reaffirmed scientific suspicion that the Atacama could be the key to unraveling the mystery of the soil samples studied by Mars missions like the MSL and the Viking.