Forty years ago, we landed on Mars… and found life?
“The team held their breath as the control experiment was performed, and this is where things get fishy. Subsequent injections of radioactive nutrients failed to produce any response; what we were seeing was consistent with either organic or purely chemical, inorganic processes. Perhaps there wasn’t life on Mars, after all. Despite the initial declaration — that if any of the three tests came back positive, we’d announce life on Mars — these results seemed to be inconclusive. In the forty years since, we’ve never replicated the experiment, and we still don’t know for certain.”
On July 20, 1976, the Viking 1 lander touched down onto the Martian surface, followed just a few weeks later by Viking 2. On board both landers were a suite of three experiments designed to look for signs of life. While the Gas Chromatograph-Mass Spectrometer and the Gas Exchange experiment both came back negative, the Labeled Release experiment — where nutrient-rich molecules tagged with radioactive carbon-14 were added to the Martian soil — gave off a positive release of radioactive CO2. Did our first trip to Mars really find life after all?