Did NASA find life on Mars 50 years ago and accidentally kill it?
Back in 1976, NASA’s Viking Landers looked for life on Mars and came up empty. Today, a group of scientists argue that, on the contrary, we definitely found evidence of microscopic alien life … but we killed it by accident.
When Viking 1 and 2 landed on Mars, they ran a series of experiments on Martian soil. In one test, researchers added water and nutrients labeled with radioactive carbon. If microbes were present, they would metabolize the nutrients and release radioactive carbon dioxide.
That’s exactly what happened, at least the first time.
NASA may have found life on Mars 50 years ago, then accidentally killed it
The lander detected a significant release of radioactive gas. But follow-up injections were not so fluffy. Follow-up experiments yielded equivocal results, so NASA concluded that the positive signal was likely caused by unusual soil chemistry rather than the presence of life, famously leading Viking project manager Gerald Soffen to officially—and mournfully—declare that Mars contained “no organics, no life.”
At the time, traces of chlorinated organic compounds were dismissed as pollution from the Earth. But decades later, Mars missions have confirmed that the chemical compound perchlorate, once blamed for the negative result, is native to Martian soil. Thanks to years of research on Earth, we now know that heating perchlorate can destroy organic matter and produce the kind of chlorinated compounds that Viking discovered in the 70s.
All this is a roundabout way of saying it, according to the researchers who published their findings in the journal AstrobiologyViking may have found organics after all, but then we accidentally killed them because we didn’t know what we were dealing with yet.
In the paper, the researchers argue that based on the “preponderance of evidence,” the Viking probe has definitely detected microbial life. They had even named this hypothetical, sadly killed organism: BARSOOM, which stands for Bacterial Autotroph Respiring with Stored Oxygen On Mars. Sci-fi geeks may recognize it as the name of Edgar Rice Burroughs’ influential 11-volume sci-fi fantasy book series. The scientist’s version of BARSOOM could, again hypothetically, survive near the surface in a semi-dormant state.
Soaking them with water may have killed them, as we’ve seen here on Earth: Desert microbes adapted to extremely dry conditions can die when soaked with water. The authors of this paper don’t claim to prove this theory conclusively, but they do call for a major re-examination of the data before future missions so we don’t accidentally kill the very thing we’re looking for… again.
