Surface Chemistry of Titan Options

[Juramike]

The bulk of the liquid in the lakes on Titan is going to be a methane/ethane combination, but a lot of polymeric organic material is going to have been washed in from the terrain, as well as blown in from the dunes. (The lakes would be a dune trap). That means ice-silt and tholin-coated ice silt.

The higher-order organic polymers may act as a surfactant to coat the ice particles. I would hazard that the hydrophilic functionalities of the polymer subunits would side with the ice particle surface and the hydrophobic parts of the polymer would face the methane solvent. This would allow some really gnarly emulsions to set up.

A cross-section of a lake on Titan would look like a classic "nightmare extraction" sitting in a sep funnel in an organic chemistry laboratory. There would be a foamy goo or scum component floating on the surface, the methane/ethane layer as solvent possibly with low density organic shmeggums floating about, then a denser loose gelatinous organic polymer/solvent component full of organic yukkies (please excuse the med chem. technical jargon), then a more dense portion of organic polymer/organic solvent/water emulsion, and finally a water-ice silt bottom.

Water (ice) and organics are immiscible. But hexanes and acetonitrile (CH3CN) are also immiscible. By analogy, methane should also be immiscible with CH3CN (which would be a solid at Titan’s temperature, but a lower density component than ice). This should make for yet another fun emulsion possibility. [I’ve seen waaaaay too many ugly emulsions in sep funnels with “simple” organic components.]

With the complex organic chemistry at Titan, there is a very real possiblitiy of multiple layers of emulsions combined with an organic scum layer at the surface.

I’m not sure how any of this would affect specular reflections or even radar penetration. The surface would not look like the pretty foam of a bubble batch but more like the curd on overcooked pea soup.. Would certain layers reflect radar better than others? Can you get specular reflection when there are bubbles or “floaters” on the surface? What if the “floaters” are soft low density organics? How do organic emulsion blobs reflect radar?

The patterns we are seeing in the lower parts of the lakes may be channels in the goopy lower emulsion layers (think of the orange crud at the bottom of scummy ponds). I could imagine a scenario when higher density organic goo flows into the lakes and carves a path through the less dense emulsion. The real “bottoms” of the lakes may lie under meters of organic emulsion.

Lakes on Titan may resemble more of an open pit hazmat toxic waste dump (although I still like to think of it as “a pristine prebiotic environment”).


-Mike

[nprev]

No apology necessary at all, Chemist; your point was a good one, made me think!

On Earth, organic chemistry outside of organisms is an afterthought compared to the inorganic processes that shape the planet's surface and disregarding the physical effects of life's ubiquitous presence. However, on Titan, it seems that the reverse is true, or it would look much more like a "conventional" terrestrial world (or at least like a gassy traditional icy moon).

This is a fairly radical paradigm shift when you think about it; I don't think we really anticipated the possible ramifications of this at all. Pre-Cassini, we expected a craggy wasteland that looked sort of like present-day Mars with water (with different materials of course), but still familiar. Instead, we've struggled to understand even the most basic topographic features...but making good progress!

Rough concluding thought: On Earth, organic chemistry's complexity is confined within the boundaries of cells; on Titan, it is unbound. Both manifestations alter their respective world's surfaces radically, albeit by different means.

[ngunn]

Rough concluding thought: On Earth, organic chemistry's complexity is confined within the boundaries of cells; on Titan, it is unbound. Both manifestations alter their respective world's surfaces radically, albeit by different means.

. . which leads directly to the Complex Titan question:

Do those surface alterations facilitate some sets of organic reactions and hinder others so that eventually one kind of goo-ology takes over? PURELY as a 'for instance' here is a crude example of the KIND of thing I mean.

In some puddles a reaction chain occurs that manages to 'digest' a thin layer of the icy substrate it's resting on. Puddles like that tend to avoid clogging up and becoming ex-puddles, so that reaction chain is favoured, its products become more widespread and more likely to be transported widely by occasional freak events, thus 'seeding' other puddles. Turn the clock forward millions of years and you have a system of self-deepening lake basins masquerading as calderas, and some improbably sophisticated goo.

Now I repeat I comptetely disclaim this SPECIFIC suggestion. I'm only saying the truth could be equally weird.

[nprev]

Do those surface alterations facilitate some sets of organic reactions and hinder others so that eventually one kind of goo-ology takes over?

Think you just coined a phrase, there, ngunn..."goo-ology!" I like that!

Damn interesting idea for sure, and it sounds quite plausible; no hint of deterministic system behavior, enough allowance for randomness within complexity to make it ring true with what we currently understand about how the Universe works. Certainly utter chemical chaos can't persist on a planetary scale; too much disequilibrium to last for very long. Therefore, your assumption that one set of processes became dominant (probably for random reasons) and stable in terms of maintaining systemic energy balance sounds very reasonable.

BTW, I nominate Juramike for the position of Chief Titanian Gooologist!

[ngunn]

Think you just coined a phrase, there, ngunn..."goo-ology!" I like that!

No I didn't - it's already in the official literature - but I may have added the hyphen. I think the paper in question is what originally got us going on this topic, though probably not this thread. Ralph Lorenz can probably tell us who actually coined the term.