Gilbert Levin, a NASA engineer who worked on the Viking missions, says he’s “convinced we found evidence of life of Mars in the 1970s.”

In a Scientific American article published today, Levin explains how two separate craft landed on the surface of the red planet and conducted a series of tests to determine if there were was life.

One particular test, based on the same experiment Louis Pasteur conducted to prove the existence of microbes, came back positive. The results were confirmed in a replica test by another craft 4,000 miles away. Levin’s spent the 43 years since studying the results.

According to him:

On July 30, 1976, the LR [Labeled Release life detection experiment] returned its initial results from Mars. Amazingly, they were positive. As the experiment progressed, a total of four positive results, supported by five varied controls, streamed down from the twin Viking spacecraft landed some 4,000 miles apart. The data curves signaled the detection of microbial respiration on the Red Planet. The curves from Mars were similar to those produced by LR tests of soils on Earth. It seemed we had answered that ultimate question.

So why has the government sat on this information for nearly half a century? Well, it really hasn’t. The results of the LR tests conducted during the Viking missions aren’t exactly hidden information. Scientists have taken a look before and, generally speaking, there’s no consensus that those particular experiments indicate that there is, or ever has been, life on Mars.

Critics claim the test is nonspecific and, without corroborating data, inconclusive. But, Levin says that NASA hasn’t followed up on the Viking missions with complimentary experiments to further the findings of the LR studies.

Levin’s concern isn’t that his work’s gone unfinished, but that we’re about to send humans to a planet that many scientists believe could have space germs. He warns about the dangers astronauts might face if he’s right about the results of the Viking missions:

Any life there might threaten them, and us upon their return. Thus, the issue of life on Mars is now front and center.

Levin concludes that the most logical path forward would be to focus on the LR findings:

A panel of expert scientists should review all pertinent data of the Viking LR together with other and more recent evidence concerning life on Mars. Such an objective jury might conclude, as I did, that the Viking LR did find life.

In the past couple of years there’s been a slew of evidence to support the idea that Mars, at some point in the past, had large bodies of water and an atmosphere. This is enough to convince many scientists that it would be stranger if Mars didn’t host organic life at some point in time.

But, to the best of our knowledge, there’s absolutely no scientifically accepted evidence for life anywhere outside of Earth besides the tardigrades and other microbes we’ve managed to litter the cosmos with.

There are plenty of theories, and evidence to support those theories, but there’s so far been no direct observation of extraterrestrial life.

However, If Levin is right, and there is microscopic life on Mars, we could be setting our astronauts up for some kind of space germ-based disease. For all we know the “Martian Flu” could eradicate life on Earth within minutes of the first human returning from a years-long mission to the red planet. By that token, it could also turn us into super heroes who live forever and never lose our car keys.

We should definitely figure out what the middle-ground is before we send people to an alien planet’s surface.

I'm convinced we found evidence of life on Mars in the 1970s on Scientific American

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