The carbon-assimilation experiment: The Viking Mars Lander

Abstract The carbon-assimilation experiment detects life in soils by measuring the incorporation of carbon from 14CO and 14CO2 into organic matter. It is based on the premise that Martian life, if it exists, is carbonaceous and exchanges carbon with the atmosphere, as do all terrestrial organisms. It is especially sensitive for photosynthesizing cells, but it detects heterotrophs also. The experiment has the particular advantage that it can be carried out under essentially Martian conditions of temperature, pressure, atmospheric composition, and water abundance.