Recently, a controversial theory emerged from an astrobiologist who suggested that NASA may have accidentally killed off any signs of life on Mars nearly 50 years ago. The theory is based on an experiment conducted by NASA’s Viking landers in 1976, which may have destroyed any Martian microbes that were present at the time. This article will discuss this theory further and its implications for the search for life on Mars.
Viking Mission Background
In 1976, NASA launched two Viking landers, Viking 1 and Viking 2, to the surface of Mars with the primary goal of searching for signs of life. The landers were equipped with instruments to collect samples of Martian soil and conduct experiments to detect biosignatures, molecules that indicate the presence of life. One of the main experiments was to mix Martian soil samples with water and nutrients, assuming that life on Mars would require liquid water to survive, just as organisms on Earth do.
Controversial Theory
Dirk Schulze-Makuch, an astrobiologist at Technische Universität Berlin, has theorized that experiments conducted by the Viking landers may have accidentally killed off Martian microbes. According to Schulze-Makuch, life on Mars may be very different than we imagine. Rather than relying on liquid water, Martian microbes may have lived in very dry conditions and gotten their moisture from salt deposits that suck moisture out of the atmosphere.
Experiments Conducted
The Viking landers’ experiments involved mixing Martian soil samples with water and nutrients, then monitoring them for signs of metabolism and photosynthesis. Initial results from these experiments indicated microbial activity, but after further analysis, scientists concluded that these results were likely false positives. Schulze-Makuch suggests that the experiments may have flooded the Martian microbes with too much water, causing them to die.
Implications of Theory
If Schulze-Makuch’s theory is correct, it has major implications for the search for life on Mars. NASA has long adopted a “follow the water” strategy in the search for life on Mars, assuming that liquid water is the key to life. But if life on Mars is more dependent on atmospheric salts and moisture, then this approach needs to change. Schulze-Makuch suggests that future missions should focus more on looking for hydrated, hygroscopic compounds, such as salts, that might harbor Martian microbial life.
Reaction of the Scientific Community
This theory has sparked debate among scientists. Some support Schulze-Makuch's view and suggest that the search for life on Mars should be changed. Others are skeptical and consider the theory to be unproven speculation. Nevertheless, the theory has opened up new discussions about how we should approach the search for life on other planets.
The Future of the Search for Life on Mars
With a better understanding of the Martian environment, Schulze-Makuch suggests that future missions use more diverse and independent methods of life detection. This includes looking for hydrated and hygroscopic compounds that might harbor Martian microbial life. Additionally, it is important to consider the overall ecology of Mars when designing future experiments.
Challenges in the Search for Life
Searching for life on Mars is not easy and full of challenges. One of the biggest challenges is the extreme environmental conditions of Mars, such as very low temperatures, high radiation, and a thin atmosphere. In addition, the limitations of technology and tools used in exploration missions are also obstacles. Therefore, innovation and development of more sophisticated technology are needed to detect signs of life on Mars more accurately.
Conclusion
The theory that NASA may have accidentally killed signs of life on Mars is an important reminder that the search for life on other planets requires a careful and multifaceted approach. While this theory is speculative, it demonstrates the need to consider a variety of possibilities and methods in the search for life on Mars. With a better understanding of the Martian environment, we can design more effective experiments and avoid mistakes that may have been made in the past.
