Produced by: Mohsin Shaikh
Credit: NASA
Despite decades of exploration, no conclusive evidence of life on Mars has been found—though past missions may have come closer than we think.
In 1976, NASA’s Viking landers conducted the first biological experiments on Mars, testing soil samples for biosignatures that might reveal life.
Astrobiologist Dirk Schulze-Makuch from the Technical University of Berlin suggests Viking experiments may have unintentionally destroyed potential Martian life.
The Viking landers found chlorinated organics, initially thought to be contamination. Today, we know these compounds exist on Mars, though their origin remains unclear.
Credit: NASA
Viking’s gas chromatograph-mass spectrometer heated soil samples, possibly incinerating organic compounds and leaving us without a true reading of potential Martian life.
Credit: NASA
Schulze-Makuch speculates that by adding water, we may have “drowned” dry-adapted Martian microbes, assuming life on Mars would require the same conditions as Earth.
Interestingly, Viking’s pyrolytic release experiment showed stronger life signals in dry conditions. Did we overlook signs of Martian life by dismissing this?
Schulze-Makuch suggests looking beyond water, focusing instead on dry-tolerant, hydrogen peroxide–using microbes. Mars may host life in ways we hadn’t considered.
Nearly 50 years after Viking, Schulze-Makuch urges another mission to search for life on Mars, equipped with our improved understanding of its unique environment.