Soil ‘cocktail’ suggests life on Mars

USC (US) — Mathematical analysis of soil from Mars indicates there may be life on the planet.

In 1976, the National Aeronautical Space Agency launched the Viking program, sending space probes to Mars to determine whether there was life on the red planet. Thirty-six years later the debate about life on Mars is not over.

Joseph D. Miller, associate professor of cell and neurobiology at the Keck School of Medicine at the University of Southern California (USC) and colleagues conducted an independent analysis of the labeled release (LR) data from the Viking 1 and 2.

The researchers applied mathematical measures of complexity to the data, which indicate a high degree of order that is more characteristic of a biological rather than a non-biological, purely physical process.

The research was published online in the International Journal of Aeronautical and Space Sciences.

In the experiments, the Viking landers dropped on Mars about 4,000 miles apart, scooped up soil samples and applied a radiolabeled nutrient cocktail to the soil. If microbes were present in the soil, they would likely metabolize the nutrient resulting in the release of CO2 or possibly methane (CH4).

The active experiments did indicate metabolism, and control experiments on sterilized soil samples produced little or no gas release. But due to lack of support from two other Viking experiments that did not find any organic molecules in the soil, most scientists believed the data had been compromised by a non-biological oxidizing property of Mars soil.

Miller and colleagues did not accept this interpretation, and over the last six years applied measures of mathematical complexity to the data from active and control Viking data, as well as terrestrial biological and non-biological data sets.

Not only did the active Viking LR experiments exhibit higher complexity than the control experiments, but the active experiments clearly sorted with terrestrial biological data series whereas the Viking LR control data sorted with known terrestrial non-biological data.

“To paraphrase an old saying, if it looks like a microbe and acts like a microbe, then it probably is a microbe,” says Miller, who is a neuropharmacologist, but also studies circadian rhythms at USC and is an author on the research.

“The presence of circadian rhythmicity and a high degree of mathematical complexity or order in the LR data most likely means Viking discovered microbial life on Mars over 35 years ago.”

Without a protective atmosphere similar to Earth’s, life on Mars is more likely to exist underground, where it is safe from ultraviolet radiation, Miller said. If life does exist on Mars, the knowledge could unlock secrets of life here on Earth.

“We have only one example of life in the universe — we are it,” says Miller. “Finding another example of life somewhere else could be the biggest step forward in biology since the delineation of the genetic code by Crick and Watson.”

Though the research offers tantalizing proof, much more is needed. Miller thinks it’s time to send a probe back to Mars to make the definitive determination.

“This research is not a smoking gun,” he says. “A smoking gun would be taking a picture under a microscope of Mars bacteria. But the case is getting stronger. We know there is sub-surface water ice, and perhaps liquid water in regions that seem to release methane gas into the atmosphere.

“Water is necessary for life and methane is a potential signature of biology. There’s enough circumstantial evidence that strongly suggests NASA or the European Space Agency should consider explicit life detection experiments on Mars.”

Joining Miller in the new research is Viking principal investigator Gilbert V. Levin, adjunct professor, Arizona State University, Giorgio Bianciardi, researcher in human pathology and oncology at University of Siena, Italy, and Patricia A. Straat, co-investigator on the Viking LR studies (retired).

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  1. Dr.Kathrine Martinez-Martignoni


  2. cdsmith

    I knew back then when I was just a freshman that the lander had found life on Mars. The experiment worked exactly as it should have and returned the results that it was designed to return. I was flabbergasted when NASA retracted their earlier statement that they had found life.

    I believe that the reason NASA backtracked in 1976 was that cultural perceptions at the time were not ready for the news. Today the populous of the western world is more readily able to grasp the concept of life beyond Earth.

  3. JEQP

    This is interesting, but I’m not convinced. The evidence is circumstantial and I think if there was life there would be more evidence, so I’ll wait for Miller’s smoking gun.

  4. AQM

    Now this is interesting. If it was truly an attempt at censure to calm populations then it can only mean that NASA is in agreement with religious leaders about the release of sensitive physical information. How could they possibly? Ha ha!
    It is also a huge coincidence that this bombshell coincides with the release of a blockbuster film with flagging ticket sales.
    Is somebody about to tell us something? Doo doo doo doo, Doo doo doo doo!

  5. Girdhar Kalidasu

    It is very important to relook at data which may lead to better interpretation, that was what Miller’s at. I appreciate their effort. It is very important to have direct evidence, the acquisition of which regained importance through Miller’s work.

  6. NC Lawyer

    Quit speculating. Let’s get more evidence.

  7. Kevin Orrman-Rossiter

    I think the science is weak, quoting a saying “If it looks like etc. ” is not a substitute for good science. The mathematical analysis does not present compelling evidence that they are looking at biological activity rather than geochemical activity. If anyone doubts this then I suggest they read such great works as “How nature works” by Per back and “Wetware” by Dennis Bray. The first illustrates how ‘alive’ self-organized critical systems can appear. The second one looks at very simple cells and explores issue of what is ‘alive’ and what is chemically driven (behavior) activity.

  8. Dr.Kathrine Martinez-Martignoni

    I think (but this is only my personal opinion!!!) that NASA,ESA,etc… already know very well that there is LIFE ON MARS (and in our solar sistem in general) but scientists only now are authorised to speak freely of these items (like: life on mars,UFOs, aliens,etc….) that once were considered “questions very dangerous to debate publicly and openly” .
    Dr. kathrine M.

  9. AQM

    Dr. Katherine you may be correct. The evidence is there from past and present for ALL to open their eyes and see.
    May the force be with you.

  10. Dr.Kathrine Martinez-Martignoni

    Thank you, AQM….!!!

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