Former NASA researcher Gilbert V. Levin is convinced that life on Mars was discovered back in the 1970s after an experiment detected the presence of microorganisms, the scientist explained in an article entitled “I’m Convinced We Found Evidence of Life on Mars in the 1970s” published by Scientific American.
During a pair of NASA missions in 1976, Viking Landers 1 and 2 collected several samples from the Martian soil that were then tested for signs of carbon dioxide or microbial respiration through a Labeled Release (LR) life detection experiment in which Levin took part.
The test used to prove that microorganisms were present in the planet’s soil initially revealed four positive results supported by five varied controls duplicated by both landers that on the planet were located more than 6,000 km from each other.
However, a further Viking Molecular Analysis Experiment aimed at searching for specific microorganisms failed to detect organic matter in the planet’s soil, suggesting that LR’s results found an imitation of life, rather than organic life itself.
Levin found it disappointing that none of NASA’s subsequent missions to Mars carried instruments that could potentially detect life on the planet and confirm the previous findings.
“Inexplicably, over the 43 years since Viking, none of NASA’s subsequent Mars landers has carried a life detection instrument to follow up on these exciting results", Levin wrote in the article. “Instead the agency launched a series of missions to Mars to determine whether there was ever a habitat suitable for life and, if so, eventually to bring samples to Earth for biological examination".
He also pointed out that despite NASA maintaining the search for alien life remained “among its highest priorities” because any microbial life on Mars could potentially threaten astronauts sent to the planet, as well as Earth's population upon their return, the organic matter in the planet’s soil has not been properly studied.
“In summary, we have: positive results from a widely-used microbiological test; supportive responses from strong and varied controls; duplication of the LR results at each of the two Viking sites; replication of the experiment at the two sites; and the failure over 43 years of any experiment or theory to provide a definitive nonbiological explanation of the Viking LR results", Levin said, arguing that the existing evidence still points toward signs of life on the Red Planet, prompting further research.
“NASA has already announced that its 2020 Mars lander will not contain a life-detection test", the former NASA researcher said. “In keeping with well-established scientific protocol, I believe an effort should be made to put life detection experiments on the next Mars mission possible".
Levin insists that the future missions to the planet should carry out an equipment that would help to determine the presence of microorganisms and revise the results found in his experiment.
“The study would likely produce important guidance for NASA’s pursuit of its holy grail", the researcher concluded.
Gilbert V. Levin remains one of the scientific advisers to the International Committee Against Mars Sample Return, warning about bringing back to Earth samples of soil and rocks from Mars that could contain possible pathogenic viruses and insists that the study of alien life on Mars should be carried out with the use of detection instruments directly on the planet.