Liquid oceans in our solar system

[Hercules Rockefeller]

I suppose this is planetary science with implications for exobiology, but I’m posting in the Bio subforum in order to pick the brains of the biologists.

Did anyone see this? http://antwrp.gsfc.nasa.gov/apod/ap070530.html

I’m surprised this didn’t get a lot more attention and press than it seemingly did, if indeed it does turn out to be a smallish shallow liquid sea. My question is: is this the only instance of a liquid sea other than on Earth? To my knowledge it is which is why I’m so surprised at its lack of coverage. I think Venus has liquids in its atmosphere due to its high pressure but as far as I know they are in the form in tiny suspended droplets, so this doesn’t compare to a large sea.

Another of my questions is: if this is a sea of liquid hydrocarbons, just how suitable is such an environment for life as we know it? I’m not much of a biochemist but I thought that hydrocarbons are not particularly polar molecules. Don’t phospholipid bilayers (and many other aspects of cell physiology) form due to the polar nature of water? This prompts molecules with hydrophilic/phobic ends to align themselves with each other as a result. Without that polar environment can these structures form?

 

[S.A.M.]

How do they figure it for hydrocarbons?

 

[2inquisitive]

Here's a link to a NASA article of the paper that appeared in Nature.
http://saturn.jpl.nasa.gov/news/features/feature20070103.cfm

Titan is quite an interesting place. The only known body with a nitrogen-rich atmosphere besides Earth, thicker than Earth's atmosphere. Probable methane rains and volcanos. Possibly a subterranean liquid water layer heated by a hot core. Here's a copy & paste from wiki:
[edit]

Life on Titan
Scientists believe that the atmosphere of early Earth was similar in composition to the current atmosphere on Titan. Many hypotheses have developed that attempt to bridge the step from chemical to biological evolution. The Miller-Urey experiment and several following experiments have shown that with an atmosphere similar to that of Titan and the addition of UV radiation, complex molecules and polymer substances like tholins can be generated. The reaction starts with dissociation of nitrogen and methane forming hydrocyan and ethyne. Further reactions have been studied extensively.[51]

All of these experiments have led to the suggestion that enough organic material exists on Titan to start a chemical evolution analogous to what is thought to have started life on Earth. While the analogy assumes the presence of liquid water for longer periods than is currently observable, several theories suggest that liquid water from an impact could be preserved under a frozen isolation layer.[52] It has also been suggested that liquid ammonia oceans could exist deep below the surface.[53] Furthermore, Titan's distance from the Sun and the anti-greenhouse effect of its cloud cover, as well as the absence of CO2, would further limit the option for a fully analogous environment. With these many obstacles, the topic of life on Titan may best be described as a thought experiment for examining theories for life's origin on Earth.[54] In other words, if life were able to develop on Titan, it would provide a mirror for examining the evolution of life on Earth. This line of reasoning has been challenged, however, by an alternate explanation for life's hypothetical existence on Titan. It has been proposed that, if life were to be found on Titan, that it would be statistically more likely to have originated from Earth than to have appeared independently. Research conducted by Brett Gladman of the University of British Columbia theorizes that large asteroid and cometary impacts on Earth's surface have caused hundreds of millions of fragments of microbe-laden rock to escape Earth's gravity. Further calculations indicate that a number of these would encounter many of the bodies in the solar system, including Titan.[55][56]

While the Cassini-Huygens mission was not equipped to provide evidence for biology or complex organics, it did support the existence of an environment on Titan that is similar, in some ways, to that of the primordial Earth

http://en.wikipedia.org/wiki/Titan_(moon)#_note-17

 

[orcot]

They suspect that around 2 % of Titan chould be covered with those lakes

 

[Mosheh Thezion]

isnt it methane???

-MT

 

[Hercules Rockefeller]

isnt it methane???

Yes, the lakes/seas are thought to be liquid methane and ethane.

 

[Ophiolite]

My question is: is this the only instance of a liquid sea other than on Earth?

There is strong evidence suggestive of a northern polar sea on Mars. Of course its water has long since evaporated, or frozen into the polar caps.

 

[Billy T]

...My question is: is this the only instance of a liquid sea other than on Earth?...

Not likely to be of much interest to the biology of any life form I can imagine, but in answer to your question:

Assuming (as I seem to recall is the prevailing opinion) that the atmosphere of Venus is reducing (not oxidizing) there is good chance (I think) that there may be lakes (of lead) on the surface of Venus. Perhaps radar studies have been detailed enough to rule this out, but the surface temperature will melt lead.

 

[orcot]

Not likely to be of much interest to the biology of any life form I can imagine

I firmly disagree any proces that is observed on 2 planets (okay one is a moon) proofs that partial covering of a planets surface with liquids is something that chould be expected from most exo solarsystems with planets. Increasing the change on posible exo life considering with what we know today.

ne:is the average number of planets that can potentially support life per star that has planets

I do believe that ne slightly increases with this