Is the source of so much Methane on Titan being overlooked?
Tons of very intelligent and knowledgeable people already looked at it, so the answer in undoubtedly "no", so I guess my question is more along the line: "why so? I don't understand why there's so much confidence that the source of Methane on Titan is not biological."
Why am I actually asking this?
I remember a huge excitement about Methane having been found on Mars' atmosphere before the excitement waned because the amounts were too low and it didn't appear to repeat (ex: with season). Methane is, I learnt, a pretty volatile molecule that will degrade quickly and, thus, needs to be replenished continuously - any methane found needs to have been produced recently (in geological terms). Additionally, it is a known biological "waste" product of biological processes on earth, hence the initial excitement about the discovery on Mars.
In early periods of life on Earth (Archaean Eon?) the Methane producing "bacteria" (the Archaea methanogens) possibly ruled the Earth, probably producing lots of Methane that would be released into the atmosphere (akin to Titan's atmosphere of nowadays, I would guess). Oxygen-producing life dramatically changed the atmosphere compositions, making it toxic to the methanogens which became relegated to swamps, underground, guts of animals etc (wherever it's oxygen-free) and made all methane react with the oxygen.
Doesn't Titan's atmosphere give strong reasons to believe the hypotheses that there's methane-producing life pumping out all that methane? In a similar way to what might have been Earth's past before the great oxygenation event, allowing life millennia of methane production to end up with a thick atmosphere, and similar to how Earth accrued a strong envelope of Oxygen after millennia of oxygen production?
One of the hypotheses for so much Methane is some geochemical process but .. there's so many bodies in the solar system, from warm to cold, from tiny to large, and yet isn't Titan the only one with (remotely) so much Methane?