According to Dirk Schulze-Makuch from the Technical University Berlin, there is a possibility that alien life on Mars was inadvertently wiped out around 50 years ago due to a scientific experiment that involved adding water to the Martian soil. Schulze-Makuch suggests that this experiment, known as the Viking Labeled Release experiment, could have led to the drowning of any potential life forms that might have existed on the planet.
Conducted in the 1970s as part of the Viking landers’ mission on Mars, the Viking Labeled Release experiment was one of three biology experiments aimed at identifying living microorganisms in the Martian soil. The experiment involved mixing soil samples with a nutrient solution and measuring the release of radioactive carbon dioxide as an indicator of potential life. The hypothesis was that if life existed on Mars, microorganisms in the soil would consume the nutrients and emit radioactive carbon gas.
Schulze-Makuch proposes that the water added to the soil, along with the nutrient solution, might have been excessively liquid, leading to the potential extinction of any existing life forms over time. The Viking mission’s two landers touched down on Mars in 1976, specifically on July 20 and September 3.
Although the Viking Labeled Release experiment produced positive results at both landing sites, indicating the release of 14CO2 from the soil samples, the interpretation of these findings remains a topic of debate. Some scientists attribute the positive outcomes to the presence of microorganisms in the Martian soil, while others believe non-biological processes, such as soil-based organic compound oxidation, are responsible.
Schulze-Makuch’s op-ed on BigThink highlights the limited understanding that Viking-era scientists had of the Martian environment. The experiment was conducted under the assumption that introducing water might prompt life to reveal itself in Mars’ exceedingly arid conditions. However, in hindsight, this approach might have been overly optimistic.
Drawing from examples on Earth, such as the Atacama Desert in Chile, where various life forms adapt to increasing aridity, Schulze-Makuch advocates for a new Mars mission centered on life detection. He suggests exploring potential habitats on Mars, such as the Southern Highlands, where life could potentially persist within salt rocks near the surface. Schulze-Makuch eagerly anticipates the launch of such a mission dedicated to investigating these hypotheses.