[X] My Assistant

[belleraphon1]

All....

The Lakes and Seas of Titan: Observations From Cassini RADAR

http://saturn.jpl.nasa.gov/multimedia/prod...27_Mitchell.pdf

http://saturn.jpl.nasa.gov/multimedia/prod...RM_Mitchell.wav

http://saturn.jpl.nasa.gov/multimedia/prod...nscript_raw.doc

Perhaps due to the Holidays, this was not noted before...

Enjoy

Craig

p.s. what fill 12/20/07 SAR reveal?

http://saturn.jpl.nasa.gov/news/events/tit...71220/index.cfm

"Cassini successfully completed its most recent Titan flyby on Dec. 20, 2007, and data are currently being analyzed. During this flyby, the radar instrument studied Titan's "deep south." This will allow scientists to contrast this region against what they found in the lake regions of the north polar area. The spacecraft went as far south as 70 degrees. The radar imaged areas of the Tsegihi region it had not yet seen, and got some overlap in coverage. New ground was covered south of the dune fields of Belet. "

[belleraphon1]

Your welcome Nprev..

Juramike.... from p 35 of the transcipt

"If this is therefore karst, and if the depths of these lakes which we have in places mentioned a few hundred meters is indicative of a fitness of a non-waterized soluble layer, then we actually have an extensive and thick polar cap.

Now this isn’t like the polar cap on the Earth in that it’s not something that will face changing into liquid or melt. The liquids and the (unintelligible) in polar regions are actually quite different chemistries."

Your precipitated layer is the solid hydrocarbon polar cap.

Now... why does this only occur at the pole? Atmospheric circulation dumping more solid hydro precipitates at the pole as snow? Temperatures and humidity just right to allow methan/ethane/nitrogen precipitation in liquid phase?

Really neat picture..... really want that south pole SAR!!!

Craig

[Webscientist]

What a present for christmas, this paper from Mitchell, very well illustrated!
The findings upon the behavior of hydrocarbon molecules on Titan confirm that they are "natural lego" which can form very complex molecules. I still have in mind one of the latest news revealing complex hydrocarbon molecules in Titan's upper atmosphere ( a molecule of 10 000 atoms!).
So what occurs when the carbon atoms encounter (and interact with) a hydrocarbon solvent like what is probably found in those bodies of liquid(s). That's what I'm eager to know.

[Juramike]

So what occurs when the carbon atoms encounter (and interact with) a hydrocarbon solvent like what is probably found in those bodies of liquid(s). That's what I'm eager to know.

It probably resembles the non-halogenated organic waste container in a typical organic chemistry lab. The ratio of solvent, to goo, to gunk probably varies from lake to lake. The goo to gunk ratio might not vary much - it might depend more on relative solubilites of the components and the size of the "solventshed".

Another analogy might be the lower level of the tray after cleaning a chain (motorcycle, chainsaw, bicycle) or other motor part in gasoline. At some point there will be hydrocarbon solvent (gas), and gunk - some polymeric material that doesn't really dissolve in the gasoline, but gets loosened up enough to drop off the chain. The color is probably pretty close to Titanian lake sediments too (hint: not pretty).

-Mike

[nprev]

At some point there will be hydrocarbon solvent (gas), and gunk - some polymeric material that doesn't really dissolve in the gasoline, but gets loosened up enough to drop off the chain. The color is probably pretty close to Titanian lake sediments too (hint: not pretty).

-Mike

Uh...yecchh!!!

Question: Do we see anything in the SARs that resemble completely filled in lakes from this crap? Seems as if this might be an analog to terrestrial sedimentary fills of similar lakes. Harkening back to Alaska again, I'd often see former lakes that had long since filled in & had young trees sprouting on them; they were pretty easy to identify in contrast to the surrounding terrain.

[Juramike]

Question: Do we see anything in the SARs that resemble completely filled in lakes from this crap?

I think it will be hard to tell between something that was filled in, and something that is (temporarily) dried up. Especially since we don't know the properties of stuff when if dries up. Does it make a smooth coat? Or does it chunk up into radar brighter blobbies of gunk or goo? (picture dead jellyfish on a beach after a storm - yuk!)

Here is a picture of an ex-lake that has either dried out or has filled in. The ex-lake is outlined in blue, but there are other darkish shapes in the same area. The much darker shapes are possible lakes. This is from PIA01943 and is located roughly at [80N,357W]. It has a brighter RADAR signature, so it either has clumps of stuff on the surface from drying out, or stuff that plopped down from the atmosphere. Both would make the surface rougher and appear RADAR brighter than a smooth RADAR-dark surface.



Down near the lower edge of the outlined lake appears to be a cute little dune patch. These seem to be the polar/temperate style dunes, rather than the big humungous equatorial style dunes.

Since there are dunes on the lake bed, it indicates that the lake has either dried out and been that way for a while, or that the lake has filled in. Either way it has been dried out at least on the timescale of dune formation.


-Mike