Posted inAstrobiology Life on Mars Mars
Autotrophy on Mars (3): Misinterpreting the Viking Photosynthesis Experiment
Viking’s carbon fixation experiment looked for conversion of ¹⁴CO₂/¹⁴CO into organics, but its two-signal (“Peak 1” vs “Peak 2”) readout is ambiguous because inorganic carbonate/bicarbonate retention can mimic fixation and oxidants can convert labeled organics back into ¹⁴CO₂ during heating. The discovery of perchlorate strengthens an alternative interpretation in which Peak 1 could include combustion-derived ¹⁴CO₂ from fixed organics—meaning Viking may have measured substantially more carbon fixation than the original interpretation suggested.








