What is the source of methane on Mars?

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Discussion Overview

The discussion centers around the potential sources of methane detected in the Martian atmosphere, exploring various hypotheses including geological processes, biological activity, and comparisons with Titan's methane environment. The scope includes theoretical considerations, speculative reasoning, and references to planetary science.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants suggest methane on Mars could be released from pockets in bedrock, created by geochemical processes, or produced by biosynthesis from living organisms.
  • Others draw parallels with Titan, noting its ability to retain methane due to low temperatures and reduced solar wind, raising questions about the differences in atmospheric conditions between Titan and Mars.
  • A participant mentions the possibility of 'fossil' methane as a source, indicating that researchers cannot rule it out.
  • Concerns are raised about the presence of C14 in Martian methane, with some arguing that it would not be expected due to the lack of a similar atmospheric process as on Earth.
  • There is a discussion about the potential for abiogenic sources of hydrocarbons, with some participants expressing skepticism about the predominance of biogenic sources in Earth's fossil fuels.
  • One participant questions the likelihood of finding evidence of life on Mars, suggesting that if life were similar to that on Earth, there would be more evidence of it across the planet.

Areas of Agreement / Disagreement

The discussion remains unresolved with multiple competing views on the sources of methane on Mars. Participants express differing opinions on the significance of biological versus abiogenic processes, and there is no consensus on the implications of methane detection.

Contextual Notes

Participants highlight limitations in determining the origins of methane, including the decay of C14 over time and the challenges in distinguishing between biological and chemical formation processes. The discussion also reflects varying interpretations of geological evidence and atmospheric conditions.

jim mcnamara
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http://www.nasa.gov/mission_pages/mars/news/marsmethane.html

NASA reports evidence of methane in the Martian atmosphere. There are several ways to explain the methane -

Methane trapped in pockets in the bedrock being released

Methane being created at greater depths by geochemical processes, driven by heat from the core

Biosynthesis of methane - ie., living bacteria like organisms.


At the meeting several of the geologists suggested that the biosynthetic explanation may not be too far fetched because the seimic activity and core heat of Mars are minimal.
 
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jim mcnamara said:
http://www.nasa.gov/mission_pages/mars/news/marsmethane.html

NASA reports evidence of methane in the Martian atmosphere. There are several ways to explain the methane -

Methane trapped in pockets in the bedrock being released

Methane being created at greater depths by geochemical processes, driven by heat from the core

Biosynthesis of methane - ie., living bacteria like organisms.


At the meeting several of the geologists suggested that the biosynthetic explanation may not be too far fetched because the seimic activity and core heat of Mars are minimal.

I remember Titian has its methane rain and frozen methane deserts.

Isn't Titian minimally active as far as core heat and seismic activity go?
 
Titan has liquid methane because of low temperatures and greatly reduced solar wind compared to Mars. On Mars methane gas exits the atmosphere after a while. Titan is able to hold onto it.

The reducing atmosphere of Titan is it's primary atmosphere, the one from original plantaery (moon-etary?) formation. It's atmosphere is like the one Earth had before the genesis of photosynthetic oxygen. Earth has a secondary atmosphere now.

Anyway, that is why the researchers cannot rule out 'fossil' methane as a source of the gas they are seeing.
 
jim mcnamara said:
Titan has liquid methane because of low temperatures and greatly reduced solar wind compared to Mars. On Mars methane gas exits the atmosphere after a while. Titan is able to hold onto it.

The reducing atmosphere of Titan is it's primary atmosphere, the one from original plantaery (moon-etary?) formation. It's atmosphere is like the one Earth had before the genesis of photosynthetic oxygen. Earth has a secondary atmosphere now.

Anyway, that is why the researchers cannot rule out 'fossil' methane as a source of the gas they are seeing.

Thank you. Very interesting. Could be Martian cows.
 
baywax said:
Thank you. Very interesting. Could be Martian cows.

More likely Buggalo. :smile:

I heard about this, the only way to test it is to send a probe and collect some, shouldn't the Carbon in methane contain more C14 than chemically laid down carbon?
 
The Dagda said:
shouldn't the Carbon in methane contain more C14 than chemically laid down carbon?
C14 is formed from N14 in the Earth's atmosphere - I wouldn't expect very much C14 in Mar's atmosphere.
 
mgb_phys said:
C14 is formed from N14 in the Earth's atmosphere - I wouldn't expect very much C14 in Mar's atmosphere.

I see so how would we go about determining if a sample was chemically formed or biologically formed?
 
On mars? no idea!
Any trace of C14 would be interesting - but if it was biologically formed millions of years ago there wouldn't be any C14 anyway (it would have decayed).
You might find He3/He4 istopes mixed in, He4 would suggest it came from underground He3 would imply extraterrestrial (or whaterver is latin for extra-mars?) ie. from comets/meteors
 
i see no reason why much of the "fossil" fuel on Earth can't be abiogenic. the solar system is full of hydrocarbons.
 
  • #10
Proton Soup said:
i see no reason why much of the "fossil" fuel on Earth can't be abiogenic.
Geological opinion would be against you
 
  • #11
mgb_phys said:
Geological opinion would be against you

no reason to believe much of the biogenic is fossil-sourced, either. plenty of anaerobes making methane and such.
 
  • #12
Proton Soup said:
no reason to believe much of the biogenic is fossil-sourced, either. plenty of anaerobes making methane and such.

Actually there is a significant amount of C14 in fossil fuels that can pretty much only be explained if the matter was once part of a living thing.
 
  • #13
Sweet! Perhaps we can lease one of our drilling rigs to NASA so they can do some natural gas exploration! :smile:

CS
 
  • #14
The Dagda said:
Actually there is a significant amount of C14 in fossil fuels that can pretty much only be explained if the matter was once part of a living thing.

sure, and methane is constantly being produced on the seafloor by archaea, but it's not like all that was produced millions of years ago by decaying dinosaurs and ferns, it's a continuous process.

and what percentage of that significance do you think accounts for living things as a source of hydrocarbons?

anyhoo, i can't say i'd be shocked if subterranean microbes or their fossils were discovered on Mars. methane doesn't excite me, though. the methane could be inorganic. wake me up when they find coal.
 
  • #15
Proton Soup said:
sure, and methane is constantly being produced on the seafloor by archaea, but it's not like all that was produced millions of years ago by decaying dinosaurs and ferns, it's a continuous process.

and what percentage of that significance do you think accounts for living things as a source of hydrocarbons?

anyhoo, i can't say i'd be shocked if subterranean microbes or their fossils were discovered on Mars. methane doesn't excite me, though. the methane could be inorganic. wake me up when they find coal.

No ones disputing that methane occurs as part of non organic chemistry. But everyone's pretty sure as you intimate, that coal and oil are the result of organic life.
 
  • #16
If life on Mars was anything like life on Earth wouldn't there be evidence of it in fossil, dormant spores etc... or actual living organisms all over the planet? I mean, is there one area of Earth that does not have some evidence of life (other than Spuzzum B.C.)?
 

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