Hydrocarbons on Saturn's Moon Titan are Biological in Origin?

Sparkstation: Amazing! Any further reading on this?

Hi,

it is very likely that these hydrocarbons are not biological.

Interstellar and stellar material is mostly hydrogen.

Considerable amounts of carbon is existing too (we have a proof by spectral analysis and the chondritic meteorites and the mass ratio of the carbon isotopes therein.)

There is ample energy (light to x-ray) to do synthesis of many "species".

Infrared spectroscopy is used for analysis of these.

Many different molecules have been found in interstellar material including amino-acids!

Atmosphere of early planets is mostly methane (still existing on jupiter and Saturn and likely on the other outer planets).

This can easily be converted to higher hydrocarbons either by high pressure inside the planets and moons or by the suns radiation in the atmosphere.

So there will be a mix of different molecules: synthesis and breakdown in equilibrium.

Also deep in earth there are hydrocarbons: any volcanic event is blowing up a lot but some researchers think that this material is recycled biological material.

There have been the 5 to 6 km deep drillings in the rim of the Silljan-Ring (Sweden) that found oil, not really much but some cubic meter. This is an ancient impact crater 50km in diameter and located in granite. So there is nothing of the needed oil and gas storage materials nor the possibility of driving oil from above deep into the granite.

This is thought to be deep origin (earth-mantle) methane converted to higher hydrocarbons by a variety of pressure and temperature driven processes that are catalysed either by iron or nickel or by silicates - all abundant there down.

Out there in space the temperature is also not very agreable for biological life needing water and above zero temperatures to function.

So let us send a probe and try. If the composition of the optically active molecules is racemic (deviating the plane of polarised light means optically active, mixing 50% R with 50% L-form will do nothing with polarised light) it will be non-biological.

But have in mind that we have here on earth extreme difficulties with determination of exotic bacteria. In any kg of humid soil it is expected that minimum 1000 unknown species are living and in many exotic materials living bacteria are found that cannot be cultured. (basalts from some km deep boreholes include living exotic bacterias).

So may be there is life out there that we cannot detect. Our diagnostic tools are not really developed if there is something that differs from our well known DNA or RNA biology.

RHABE

The generally accepted theory (note I don't say correct, just popular) of hydrocarbon generation (diagenesis) relys on an ancient biological source.

There is at this time no evidence to suggest that there is a "hot, deep biosphere" refilling those drained reservoirs around the earth, and beleive me if there were the big oil companies would be the first to know and be cheering in glee.

As far as I know, only NASA has suggested an abiotic source for the methane on Titan, not any of the scientists who work in this field every day.

Dear Philo,

you are right with the statement "generally accepted theory"...

but at the same time there is ample evidence that methane is leaking from the earth mantle. This methane is certainly not of biological origin.

There is an accepted mystery about the size and distribution of oil and gas fields: there are too many big deposits and not enough small ones.

This can be explained by seeping methane from very deep sources going into solution with any existing hydrocarbon, being absorbed there and reacted to higher hydrocarbons.

See for: http://en.wikipedia.org/wiki/Abiogenic_petroleum_origin

So there is ample evidence of deep earth hydrocarbons but drilling is very costly and very difficult and not predictable. And it is not worth while as the concentration is very likely much too low to be of any worth. But seeping up and being dissolved or stored may change the situation.

RHABE

Assuming life is carbon based, and also evolved from simpler forms, the simpler forms must be carbon-based but not alive. Therefore, presence of carbon based "organic" molecules does not imply an organic source.

Methane is produced in deep stratda in the earth that has never had any diological material. Methane can be produced via the decay of certain mineral layers.

This would be true on Titan as well as other space objects.

"While it is

tempting to propose a biogenic origin, CH4 is in

fact an expected product of low-temperature fluid-rock

interaction, and its detection in the atmosphere points

to active magmatism and metamorphism on the planet."