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Updated: Jun 1, 2026
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Using Flexible Gold-Titanium Reaction Cells to Simulate Pressure-Dependent Microbial Activity in the Context of Subsurface Biomining
Published on: October 5, 2019
Using biogenic sulfur gases as remotely detectable biosignatures on anoxic planets
Shawn D Domagal-Goldman1, Victoria S Meadows, Mark W Claire
1NASA Headquarters, Washington, DC, USA. shawn.goldman@gmail.com
Astrobiology
|June 14, 2011
Summary
Organic sulfur gases like dimethyl sulfide may indicate life on exoplanets. Detecting them requires measuring ethane and methane levels in atmospheres with low UV flux, potentially near inactive M dwarf stars.
Area of Science:
- Astrobiology
- Planetary Science
- Atmospheric Chemistry
Background:
- Anoxic exoplanetary atmospheres may harbor life.
- Organic sulfur compounds are potential biosignatures.
- Remote detection of biosignatures is crucial for astrobiology.
Purpose of the Study:
- To investigate the potential of organic sulfur compounds as remotely detectable biosignatures.
- To model the concentrations of various organic sulfur gases in anoxic exoplanet atmospheres.
- To identify conditions under which these gases could be detected.
Main Methods:
- Utilized one-dimensional photochemical and radiative transfer models.
- Predicted concentrations of organic sulfur gases (CS(2), OCS, CH(3)SH, CH(3)SCH(3), CH(3)S(2)CH(3)) under various biogenic sulfur fluxes.
- Analyzed the impact of UV flux on gas concentrations.
Main Results:
- Organic sulfur gas concentrations increase with decreasing UV flux.
- Dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) may reach detectable levels under extremely low UV flux conditions, such as near inactive M dwarfs.
- An indirect biosignature is the increase of ethane (C(2)H(6)) relative to methane (CH(4)).
Conclusions:
- Organic sulfur gases, particularly DMS and DMDS, show potential as biosignatures in specific exoplanetary environments.
- Detection relies on indirect evidence: quantifying ethane and methane ratios.
- Future characterization missions should focus on these atmospheric components to identify extraterrestrial life.
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