NASA’s Viking Missions May Have Accidentally Killed Martian Life 50 Years Ago

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As a seasoned gamer of cosmic puzzles and celestial mysteries, I’ve been captivated by the tales of our Martian voyages since the days of Viking I and II. The images they beamed back to us were more than just pixels; they were windows into another world, tantalizing hints of what lies beyond our blue sphere.

During the 1970s, NASA dispatched two twin expeditions, Viking I and Viking II, towards Mars, the Red Planet. Each expedition included an orbiter and a lander, enabling astronomers to study Mars from two distinct angles. Viking I made its landing on the western part of Chryse Planitia on July 20, 1976, while Viking II touched down at Utopia Planitia approximately two months later, on September 3, 1976.

The United States’ initial missions to Mars were the first successful ones, paving the way for numerous decades of fruitful Martian exploration. Interestingly, although the Soviet Mars 3 lander reached Mars before the U.S., it only managed to send a solitary, indecipherable image before failing shortly after landing. The main objective of Viking was to capture high-definition images from Mars’ surface, and the Viking landers exceeded expectations in this regard, beaming back the first clear pictures from another planet.

The landers weren’t simply there for sightseeing on Mars; they were also armed with a collection of experimental tools designed to seek out indications of Martian life. A variety of experiments were conducted, and two of them produced preliminary findings that aligned with the existence of life. However, subsequent experiments yielded inconclusive results, leading scientists to believe that Viking failed to detect any life. Astrobiologist Dr. Schulze-Makuch offers an alternate interpretation, positing that Viking might have in fact discovered microbial life but ended up destroying it during the experimental process.

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Did NASA accidentally kill Martian life? Revisiting Viking Mars data with fresh eyes

Over several decades, we’ve gained a wealth of knowledge about how life functions on Earth and potentially beyond. Furthermore, we’ve launched eight additional spacecraft to Mars, including NASA’s Curiosity and Perseverance rovers, which are currently investigating signs of life in different regions of the planet. It’s worth mentioning that we’ve found traces of organic compounds, a finding that was also made by the Viking missions earlier on.

Schulze-Makuch proposes that the inability to definitively prove life on Mars might not primarily stem from characteristics of the planet or any potential lifeforms there, but rather from our own preconceived ideas. Since Earth is abundant with water, an essential component for life here, we tend to believe this same requirement applies elsewhere as well.

To put it simply, the Viking missions aimed to moisten Martian soil (or Mars dirt) as a means to detect potential life forms. The reasoning behind this was that if any life existed there, even in a dormant state, introducing water might make its presence more noticeable. This approach has proven effective on Earth for various small organisms that inhabit harsh, dry conditions.

Instead of thriving in water-rich environments, there are organisms on Earth that have adapted to survive in arid conditions. These life forms have developed various chemical methods for extracting moisture from the air, without requiring direct contact with water. Immersing them in water would actually be harmful and potentially fatal to them. If we were to discover similar microbes on Mars, our exploration would likely be less like a friendly greeting and more like the destructive actions portrayed by Harry Vanderspeigle from Resident Alien or Klaatu in The Day the Earth Stood Still.

Schulze-Makuch compares the situation to discovering a human in the desert, recognizing our need for water, and then immersing us in the sea instead. The basic idea holds true, but going too far can be counterproductive. Although Mars was once remarkably similar to Earth, it’s been quite different for a long time now. Schulze-Makuch proposes that any Martian life surviving today would have developed over hundreds of millions of years to thrive in the current Martian environment. Flooding them with water might account for the inconsistent findings from Viking missions.

It’s highly improbable that we’ll ever confirm whether Viking spacecraft discovered life on Mars. Finding life during our initial Martian expedition and not in any subsequent trips suggests that it’s unlikely they found (and destroyed) tiny Martian creatures. However, this scenario underscores a crucial aspect of our quest for extraterrestrial life: If we approach the cosmos with Earth-based assumptions, we could accidentally stumble upon life, potentially even harming it unknowingly. Regardless of what extraterrestrials might think about us, that’s something we definitely want to avoid.

A new plan for finding life on Mars

On Earth, we don’t have a place exactly like Mars, but the driest parts of the Atacama Desert in Chile and the Dry Valleys of Antarctica come closest to resembling Mars as our terrestrial counterparts.

In salt rocks, certain microorganisms have evolved to thrive. They obtain their necessary water through a mechanism known as hygroscopy, which allows salts to absorb moisture from the humidity present in the surrounding environment. Interestingly, these microbes are sensitive to excessive water and will perish if they come into contact with too much liquid. Intriguingly, floods within the Atacama Desert have led to the extinction of at least three-quarters of the microbial species that were previously inhabiting the area.

When researchers launched Viking to Mars, they devised tests capable of identifying Earth-based life forms. They supplied Martian soil with water and nutrients, observing for indications of growth, metabolic activity, or reproductive processes. Although this approach was strategic, it may have been based on incomplete knowledge. Any Martian microbial life would probably share more characteristics with Atacama Desert extremophiles rather than common backyard microorganisms.

If microbial life exists on Mars, it could be confined to specific areas characterized by salt deposits and higher-than-average humidity that provide suitable living conditions. In an article for the journal Nature Astronomy, Schulze-Makuch proposes that instead of solely focusing on water, as NASA has traditionally done in seeking Martian life, we should also pay attention to hydrated and moisture-absorbing minerals (salts) as potential indicators of microbial existence.

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2024-11-19 23:47