Microbial processes contribute to methane patterns on Mars

Surface-level ,abiotic interactions cannot account for the total amount of methane fluctuations seen in the atmosphere. Therefore, there must be sub-surface interactions, among which there is potential for biological processes.
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Only abiotic processes contribute to methane patterns on Mars

While surface-level, abiotic interactions cannot account for the total amount of methane fluctuations seen in the atmosphere, sub-surface processes may exist and are only abiotic.
Created at: 
2020-04-18
  Updated at: 
2020-04-18
Curator:
Abhijit Harathi   Subscribe ...

Background

Methane Fluctuations from Processes at the Poles

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Biotic processes that contribute to atmospheric methane fluctuations can exist in permafrost.

eAn experiment using Siberian permafrost methanogenic archaea showed that 90% of the archaea have the ability to survive Martian conditions.

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Only abiotic processes at the poles contribute to atmospheric methane fluctuations.

eMethane clathrate hydrates, a source of methane, can exist in conditions found at the polar ice caps of Mars and in areas of its subsurface.

Methane Fluctuations from Processes at the Surface Level

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Methane fluctuations could potentially result from biotic processes in Martian desert regolith.

eMethanogens can survive in desert regolith on Earth analogous to those found on Mars and therefore have the resources they need to produce methane in a Martian environment.

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Methane can result from light-metal oxidation interactions at the surface level of Mars.

ePhotooxidative reactions between acetate and iron(III) oxide, which is abundant in Martian regolith, forms methane.

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Simulated Martian soil has the potential to sustain methanogenic bacteria, given the right environmental conditions.

eCertain strains of methanogens in one experiment grew in JSC Mars-1 soil with carbon dioxide, hydrogen,and varying amounts of water.

Methane Fluctuations from Combined Abiotic Processes

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Abiotic processes exist but cannot explain the magnitude of methane fluctuations on Mars.

eNo significant source of abiotic methanogenesis has been found.

Methane Fluctuations from Other Sub-Surface Interactions

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Methanogenic processes have the potential to exist beneath the Martian surface because possible abiotic sub-surface processes cannot account for methane fluctuations seen.

eMethane is disappearing at a faster pace than other trace gases in the Martian atmosphere by unknown processes, indicating that a factor at the sub-surface is responsible for methane fluctuations.

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Abiotic sub-surface processes, such as hydrothermal venting, have the capability to produce methane and cause fluctuations at the magnitude seen in data.

eLow-temperature hydrothermal fluid could exist and produce the amount of methane to cover the variations seen in the Martian atmosphere.

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Liquid-rock interaction could exist at the sub-surface level of Mars and can create methane.

eIf serpentinization of rocks occurs on Mars, it may produce methane and account for the increase in fluctuations seen.