The web has been abuzz lately with stories about NASA having found microbial life on Mars during the Viking Mission of 1976.
The genesis of all these stories was an article that appeared in Scientific American written by the principal investigator on Viking's life detection experiment, Dr. Gilbert V. Levin.
A little history
The Viking Project was the first to safely land spacecraft on the Martian surface, and to send back pictures and data to Earth. The two Vikings were comprised of an orbiter, a lander, and a nuclear energy supply. That energy supply allowed data to be beamed from Mars' surface to the orbiters, then back to Earth for six years.
The experiment Dr. Levin led tested the Martian soil for organic matter and was called Labeled Release (LR). The Viking landers scooped up samples of Martian soil, then added nutrients to it. If life existed in the soil, it would consume the nutrients and emit gas as it metabolized the food. Radioactive monitors would then detect the gas.
To ensure that the reaction was biological and not chemical, a second experiment was conducted during which the Martian soil was heated to the point where any life would be killed before being tested for gas. If there was a reaction in the first test, but not the second, that implied a biological reaction, and that is exactly what NASA found, according to Dr. Levin.
However, other experiments conducted by the Viking landers failed to find organic matter, and NASA couldn't replicate the results of the test in their laboratory. NASA attributed the result of the test to either a false positive or to an unknown chemical reaction.
In the Scientific American article, Dr. Levin states that in thousands of tests of the experiment, both before and after Viking, "No false positive or false negative result was ever obtained. This strongly supports the reliability of the LR Mars data, even though their interpretation is debated."
Fast forward 43 years, and on October 16, 2019, NASA spokesman Allard Beutel refuted Dr. Levin's claims when he told Fox News that, "The collective general opinion of the large majority of the scientific community does not believe the results of the Viking experiments alone rise to the level of extraordinary evidence."
Beutel went on to say, "One of NASA’s key goals is the search for life in the universe. Although we have yet to find signs of extraterrestrial life, NASA is exploring the solar system and beyond to help us answer fundamental questions, including whether we are alone in the universe."
Are we alone in the Universe?
The 96-mile-wide crater is named for Australian astronomer Walter F. Gale and was formed by a meteor impact 3.5 to 3.8 billion years ago. At one time, the Gale crater likely held a lake, and it includes a mountain, formed as a result of the impact.
When they were heated, the soil samples released the organic compounds thiophene, methylthiophenes methanethiol, and dimethylsulfide.
Curiosity had also detected methane, the simplest organic compound, in the Martian atmosphere. Even more, interestingly, the amount of methane varied with Mars' seasons, implying a growing season and a fallow season.
Is there life on Mars or not?
To answer that question, we asked Dr. Levin what really happened back in 1976, and what he thinks the future holds for finding life outside of Earth.
IE: What prompted you to come forward at this time and at this point in your career, with the Scientific American article?
Dr. Levin: I decided to present my case to the lay public since my frequent scientific publications had mostly been in vain. Sometimes the public has more common sense than the scientists.
IE: Why hasn't NASA acknowledged the finding of life on Mars back in 1976?
Dr. Levin: NASA rightfully said, "No, organics, no life." However, they should have known that the organics detector on Viking had frequently not worked. Then, when [an]other mission found complex organics on Mars, they should have said that validated the LRs evidence for life. Instead, they never referenced the findings of organics back to the Viking LR. Now, they don't even mention Viking!
IE: Why do you think NASA avoided putting biological tests for life on Mars landers for over 40 years? Was it willful, and if so, could you hazard a guess why?
Dr. Levin: It was absolutely willful. NASA's original excuse was that if another test failed to resolve the issue of life on Mars, the NASA budget would be severely cut. But when the Man to Mars Program began, I think the reason became that, if there were microorganisms on Mars, that would slow down the project.
The public would not want the astronauts to be exposed to possible pathogens, or worse, to bring them to Earth. So, I believe that NASA now knows there are microorganisms on Mars but fears to let the news out, which could greatly slow down the project. Since there is no way to prove the bugs are not harmful, it poses quite a problem. Perhaps NASA has decided just to go ahead and take the risk.
IE: You suggested that NASA tests for right-handed sugars and left-handed amino acids, which is how they appear on Earth, and to also test for left-handed sugars and right-handed amino acids.
Dr. Levin: If their biochemistry is anything like ours, Martian microorganisms will have [a] chiral preference. A very interesting thing I have published is that, if their preference is the same as ours, it is a strong indication that Mars' and Earth's lives are related, BUT, if they are different, that means there was a second genesis, an astonishing thing.
This would strongly imply there are many life forms throughout the universe since two planets as close as Mars and Earth not only had life but of different origins. This small sample would be enough to convince many scientists [about] the ubiquity of life. ... Of course, it's possible alien organisms have no chirality but react by some other mechanism. Thus, if we find no chirality on Mars, that does not rule out life, only life like ours.
IE: Could you elaborate on your concern that astronauts to Mars could bring back some of the microbial life you found on Mars? What threat could this pose to life on Earth?
Dr. Levin: When anyone comes back from Mars, they will carry and release Mars dust into our environment. All of our attempts at cost-free landings from celestial objects have done so despite our best efforts to prevent it. The Apollo astronauts released moon dust even before they were placed in quarantine.
If there are microorganisms on Mars, some will be in the dust released. Among them could be pathogens that could affect humans directly or by damaging plants and other things in our environment.
IE: What would be the effect of microbial life on Mars if we manage to start a colony there? Would they help in terraforming Mars, or make the martian soil more suitable for agriculture?
Dr. Levin: We would have to proceed very cautiously, exposing as few people and monitoring them carefully. If the disease [does] occur, we might have to traverse the same long route to coping with the pathogens as has taken us centuries on Earth. Hopefully, our science will let us do that much faster on Mars, but still a big job. It depends on what the Martian bugs are as to whether they will help us in agriculture, etc. If not, we will probably import the needed bugs from Earth.
IE: How likely do you think "intelligent life" exists in the universe? How do you rate our ability to find and identify it?
Dr. Levin: Now that we know there are billions of planets in what we know as the "life zone" in our universe, it would be astonishing [if we] were the only "intelligent" form.
IE: What would you like to leave our readers with?
Dr. Levin: I can only advise your readers to inform themselves as much as they can on a matter like this, and to make up their own minds. Unfortunately, we have had too many recent examples where government agencies have mislead or kept the truth from us. When NASA says there is no evidence, let alone proof of life on Mars, take that with a large grain of Martian salt.