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The pyrolytic release experiment: Measurement of carbon assimilation

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The pyrolytic release experiment is one of the three life detection tests to be conducted on the 1976 Viking Lander Missions. In this experiment minimal assumptions are made about the nature of possible life forms. Such species are assumed to have adapted to the aridity of contemporary Mars. It is also assumed that any biological cycle on Mars would be initiated by the assimilation of atmospheric CO2 or CO. Both gases are known constituents of the Martian atmosphere. Hypothetical carbon cycles are proposed and methods for measuring their primary producers are described.

In the operation of the pyrolytic release experiment on Mars, the assimilation of14CO2 and/or14CO will be measured using samples of surface soil incubated under a close simulation of ambient conditions. The incubation can be performed in the light or in the dark with or without added water vapor. Pyrolytic analysis measures the extent of14C-assimilation into organic constituents of microorganisms in the soil. Presumptive evidence of biological activity would be verified by a control analysis with dry heat sterilized soil. Descriptions are given of the test programs used to ascertain the soundness of this analytical approach. The operational sequences of the flight instrument are briefly discussed.

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Hubbard, J.S. The pyrolytic release experiment: Measurement of carbon assimilation. Origins Life Evol Biosphere 7, 281–292 (1976). https://doi.org/10.1007/BF00926947

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  • Water Vapor
  • Assimilation
  • Carbon Cycle
  • Carbon Assimilation
  • Detection Test