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A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments
Published on: October 2, 2012
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Long-chain alkanes preserved in a Martian mudstone
Caroline Freissinet1, Daniel P Glavin2, P Douglas Archer3
1Laboratoire Atmosphères et Observations Spatiales, Université Versailles St Quentin Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt 78280, France.
Summary
Ancient Martian rocks contain larger organic molecules, including decane, undecane, and dodecane, detected by the Curiosity rover. These findings offer clues to Mars
Area of Science:
- Astrobiology and Planetary Science
- Organic Geochemistry on Mars
Background:
- Organic molecules in Martian rocks are key to understanding past habitability and potential biosignatures.
- Previous analyses by the Sample Analysis at Mars (SAM) instrument on Curiosity identified smaller chlorinated and sulfur-containing organics in Gale crater.
Purpose of the Study:
- To detect and identify larger organic molecules beyond six carbons in Martian sedimentary rocks.
- To investigate the preservation state and potential origin of these larger organic compounds.
Main Methods:
- Utilized a modified Sample Analysis at Mars (SAM) analytical procedure optimized for larger organic molecules.
- Analyzed the Cumberland drilled mudstone sample from Gale crater.
- Conducted laboratory experiments to support preservation hypotheses.
Main Results:
- Detected decane (C10H22), undecane (C11H24), and dodecane (C12H26) at picomole levels in the mudstone sample.
- Laboratory experiments suggest these alkanes were preserved as long-chain carboxylic acids within the mudstone.
- The origin of these detected molecules remains undetermined, with both abiotic and biological sources being plausible.
Conclusions:
- The discovery of larger alkanes expands the known range of organic molecules on Mars.
- The findings highlight the potential for preserving complex organic matter in Martian sedimentary environments.
- Further research is needed to ascertain the abiotic or biotic origin of these long-chain organic molecules.
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