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NASA NTRS · 20260002513

Diverse organic molecules on Mars revealed by the first SAM TMAH experiment

Abstract

The search for organic matter on Mars has rapidly evolved in the past decade with simple aromatic, S-heterocycles, and aliphatic organic molecules detected in Gale crater. We report the in situ detection of >20 organic molecules from clay-bearing sandstones in the ~3.5-billion-year-old Knockfarrill Hill member of Glen Torridon, Gale crater, by the Sample Analysis at Mars instrument suite onboard the Curiosity rover. These molecules were liberated by the onboard tetramethylammonium hydroxide wet chemistry experiment. Diverse thermochemolysis products, including benzothiophene, methyl benzoate, and single and dicyclic aromatic molecules were released and detected by evolved gas analysis and gas chromatography-mass spectrometry. Results indicate the experiment successfully released molecules preserved in ancient macromolecular or free organic matter within Martian bedrock despite ~3.5 billion years of diagenesis and radiation exposure.

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BibTeXRIS

Amy J Williams, Jennifer L Eigenbrode, Maeva Millan, Ross H Williams, Ophelie McIntosh, Samuel Teinturier, Janelle Roach, Charles A Malespin, Amy C McAdam, Paul R Mahaffy, Alexander B Bryk, Arnaud Buch, David Boulesteix, Luoth Chou, Jason Peter Dworkin, Valerie Fox, Heather B Franz, Caroline M Freissinet, Daniel P Glavin, Christopher H House, Sarah Stewart Johnson, James M T Lewis, Angel Mojarro, Rafael Navarro-González, Chad Pozarycki, Andrew Steele, Roger E Summons, Cyril Szopa, Michael T Thorpe, Ashwin R Vasavada. 2026-04-07. Diverse organic molecules on Mars revealed by the first SAM TMAH experiment. https://ntrs.nasa.gov/citations/20260002513

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