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Organic synthesis on Mars by electrochemical reduction of CO₂.

ABSTRACT: The sources and nature of organic carbon on Mars have been a subject of intense research. Steele et al. (2012) showed that 10 martian meteorites contain macromolecular carbon phases contained within pyroxene- and olivine-hosted melt inclusions. Here, we show that martian meteorites Tissint, Nakhla, and NWA 1950 have an inventory of organic carbon species associated with fluid-mineral reactions that are remarkably consistent with those detected by the Mars Science Laboratory (MSL) mission. We advance the hypothesis that interactions among spinel-group minerals, sulfides, and a brine enable the electrochemical reduction of aqueous CO₂ to organic molecules. Although documented here in martian samples, a similar process likely occurs wherever igneous rocks containing spinel-group minerals and/or sulfides encounter brines.

SUBMITTER: Steele A

PROVIDER: S-EPMC6209388 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Organic synthesis on Mars by electrochemical reduction of CO2.

Steele A A Benning L G LG Wirth R R Siljeström S S Fries M D MD Hauri E E Conrad P G PG Rogers K K Eigenbrode J J Schreiber A A Needham A A Wang J H JH McCubbin F M FM Kilcoyne D D Rodriguez Blanco Juan Diego JD

Science advances 20181031 10

The sources and nature of organic carbon on Mars have been a subject of intense research. Steele et al. (2012) showed that 10 martian meteorites contain macromolecular carbon phases contained within pyroxene- and olivine-hosted melt inclusions. Here, we show that martian meteorites Tissint, Nakhla, and NWA 1950 have an inventory of organic carbon species associated with fluid-mineral reactions that are remarkably consistent with those detected by the Mars Science Laboratory (MSL) mission. ...[more]

PMID: 30402538

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