Let's say something around hydrothermal vents like here on earth...

a "cooperative" web of life

This was an idea that struck me as I was just eating dinner...what about a group of bacetria/archea that cooperate and feed off of simple stuff from a Titan hydrothermal vent, and create some reactions to help each other to exist...

this is pretty tiny, only 4 critters, and all anaerobic since were dealing with a titan like place.

since were dealing with a COLD vent, I was thinking CO2, H2 would be all there would be, since I didn't want to go overboard and add in an obvious earth one.. H2S

I will try to come up with something to tae advantage of a Titan cryomagma (NH3, H2O), but I will start with the earier ones first...:P

------

Branch 1
From hydrothermal vents:
CO2, H2

From other organisms
SO4

Methanogens:
CO2 + H2 -> CH4 + H2O

->

Methane Oxidizers:
CH4 + SO4 -> CO2 + H2S + H2O ==> Branch final

Branch 1
From hydrothermal vents:
SO4

Sulfate Reducers
SO4 + 4H2 -> H2S + 3H2O ==> Branch final

Branch final
H2S, CO2 from other organisms

Sulfide reducers
H2S + CO2 + 2H2O -> SO4 + CH4

SO4 to feed other organisms, CH4 to replenish atmosphere
-----------

Ok, first of all, we have 2 branches, each branch takes advantage of different things, and so differing bugs...

Bug A create Methane, Bug B uses Methane and creates Carbon Dioxide + Hydrogen.. (H2 can escape of be used as energy by other critters)

Bug C creates Hydrogen Sulfide

Bug D uses Hydrogen Sulfide & Carbon Dioxide to creates Sulfate for use by Bug B & Bug C to create a loop. It also creates Methane to replenish the atmosphere

----

SO for a plausible version existing on Earth, I was curious if something like this can happen on Titan

ok, I guess nobody knows...

I can't see why not, although it of course depends on what is available down there and if oxidants are being cycled, etc.

My advisor postulates three different kinds of life on Titan in his most recent book.

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3 kinds eh, cool

Yeah, seems fairly radical to me, but he posits the at least possible coexistence of two kinds of CHON (carbon-hydrogen-oxygen-nitrogen) life, one mediated by water and one by some kind of ammono-water solvent, as well as silane life.

I thought it was a fairly good read, if not his best work. There's a review of it here if you're interested:
http://www.fredbortz.com/review/LifeAsWeDoNotKnowIt.htm

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Hmmm ... at what kind of temperature do you envisage this would occur? CO2 is a solid below -80°C at pressures around 1 atm. The surface of Titan has temps around -180°C. Also, I believe water would freeze very quickly on Titan, so the bugs would need to address this problem in some fashion.

Your second set of sulphide reducers are actually oxidising it, by the way.

Also, you have cycles of oxidation and reduction of both carbon and sulphur. From whence comes the energy to do this?

Reducing CO2 to methane is chemically very difficult, requiring either strongly reactive reducing agents or additional energy input from some other source. H2 ain't good enough, because CO2 is too stable to react with H2. I don't know very much sulphur chemistry, but it seems to me that cycling between oxidised and reduced forms of sulphur will require energy input from somewhere.

On Earth, the life around hydrothermal vents is driven by the chemistry of what comes out of the vents - relatively reactive molecules reacting (presumably with water and so on) to generate stable end products. The end products drift away and fresh reactants come out of the vents, so there is no cycling of different oxidation states of the same atoms. The life around hydrothermal vents harnesses the chemistry that is happening naturally.

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The quarrelsome oarsmen were rowing,
The great violinist was bowing;
But how is the sage
To tell, from the page:
Was it pigs or seeds that were sowing?

Are gravitational flexing from reacting to other members of the Saturnian system and/or embedded radioactive elements likely suspects?

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

Well, gravitational flexing can generate internal heat, so I guess you would get thermal gradients around "cryothermal vents" (to coin a phrase). Material may exit the interior at, say, a scalding hot -50°C, then rapidly cool as it moves away.

I do not know of any organism on Earth that is able to exploit a thermal gradient to generate the energy it needs to sustain itself.

__________________
The quarrelsome oarsmen were rowing,
The great violinist was bowing;
But how is the sage
To tell, from the page:
Was it pigs or seeds that were sowing?

Titan, The Satarn's largest moon, showed the soupy orange atmosphere of the moon by Huygens space craft on January 15th 2005. Ti tan is the only known satellite with an atmospheric composition mainly Nitrogen and Methane- that resembels the earliest Earthen atmospheric conditions of aboout 4 billions years ago when probably life started in the Earth. The chemical and Geo physiological process on Titan are however much different. Titan Volcanoes Issue water as Ice ,instead of molten lava & hydrocarbon particles settle as dirt on moon's surface. The surface of Titan is dominated by dark river systems, flooded regeaons are sorrunded by elevated terrain, net works of narrow drainage tunnel and a plain strewn with what may be ice boulders. The surface temperature of Titan is -180C. It is far too cold for water to exixt as lequid there. The moon surface is also too cold for any organic life to develope ever. How ever possibility that life may exist under the surface of ice if water remains there in lequid form and that the interior where temperature could reach a comparatively warm -80C ,where might also contain lequid water and amonia. Life if at all exixt there it will exixt as microbe like Areache baccteria as it was in our earth
* Some part of this postings has been Taken from "The Lancet 2005"
Dr. Pranab Kr. Bhattacharya
Mr. Rupak Bhattacharya
Mr. Ritwik Bhattacharya
Mrs. Dahlia Mukherjee
Mr. Bholanath Bhattacharya
www.unipathos.com

Which book is this...the one by Peter Ward?

I've read reviews of his stuff, isn't he the "rare earth" guy who thinks Earth is the only planet with advanced life in the universe? Depressing if you ask me. Oh yeah, this guy also wrote GORGON, about the Permian Extinction, another topic that keeps me up at night with its unrelenting, compelling depressiveness.

I like to think about cheerful things, like how organisms might be able to live in planets we think are uninhabitable, like Titan! (oops...I forgot, it's not a "planet".)

http://www.astrobio.net/news/Topic14.html

Astrobiology magazine has lots of great stuff about Titan!

There was an article on that site about Titan, I wish I had the link, called "The Living Worlds Hypothesis" by David Grinspoon. (a great author to check out.) It's an interview with Astrobiology magazine.

He talks about photochemistry in the upper atmosphere where methane is being turned into energy-rich organic molecules such as acetylene. He thinks that organisms could "eat" this. Acetylene is dangerous on Earth because of the oxygen, but he thinks that because it is so cold on Titan, chemical reactions might occur at a more moderate pace, and the energy that causes explosions on Earth might be going into metabolism on Titan.

Not being any kind of scientist I can't evaluate this theory, I can only say "gosh-wow, what a cool idea!"

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"I am happy to report that once again the universe is doing just great, thank you, purring with perfection, ever-changing same as always. Light is still cruising along at 186,000 miles per second, and the expanding universe shows no signs of contracting. At this rate, it won't be long before they'll have to let the photon belt out another notch."
Swami Beyondananda's 2007 State of the Universe address

Yeah, I'm one of only two grad students in Peter's lab. Gorgon is actually one of his few books (I think he has about 12 now?) I haven't yet read, but he has spent the better part of his career studying the Permian extinction, and it is the basis for a new set of experiments we're doing (I'm a mass extinction guy too).

He is indeed the co-author of Rare Earth although it's interesting you mention David Grinspoon, as I tend to side more with his perspective on the matter. (David's a great guy too, by the way, and he smokes more dope than almost any scientist I can name.) I much preferred the sequel to Rare Earth, but it's about how the world is going to end, so you might find that a depressing topic as well. Similar story for The End of Evolution, another excellent read.

However, his newest book (which is the one considered in this thread) is more about possibilities and ideas, I guess you could read more optimism into that...

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What's the name of that book again?

My comments will be off topic, so this should be a private email, but sorry everyone, I don't know how to write private emails on this forum.

What kind of experiments are you doing about the Permian Extinction? Would they have anything to do with the huge crater they found in Antarctica? I recall that Ward, as well as others, didn't think a comet caused the extinction. Mostly because "no crater was found." Are they eating their words yet? Or at least are they getting samples from the crater?

I loved David Grinspoon's book, and yeah, in between his scientific theories he throws in a lot of references to the 70's, being a stoner, etc. That really helps me to relate !

__________________
"I am happy to report that once again the universe is doing just great, thank you, purring with perfection, ever-changing same as always. Light is still cruising along at 186,000 miles per second, and the expanding universe shows no signs of contracting. At this rate, it won't be long before they'll have to let the photon belt out another notch."
Swami Beyondananda's 2007 State of the Universe address

I'd hold out more hope for Titanian life if Cassini hadn't found that relatively recent, enormous impact crater. That actually makes up a significant portion of its surface area. We haven't been hit like that for billions of years and look at what much "smaller" hits have done for/to Earth life.

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"The beauty of that discussion of averages is that you don't have to be an expert in Apollo or in photography in order to see where this time study "analysis" breaks down. You just have to be, well...not an idiot." -JayUtah

The book is called Life As We Do Not Know It. Highly speculative in parts but does a good job summarizing the interesting work going on in the labs of people like Steve Benner, and several people in our program here in Seattle.

No, our theories of the Permian extinction do not involve bolide impact. I thought the paper about the Bedout crater was interesting but Peter doesn't buy it, although I've never gotten a good explanation why out of him. We're looking at the precipitous drop in atmospheric oxygen from an all-time Earth high (well, presumably, and in the Phanerozoic for sure) of ~30% down to around 13% from the mid Permian into the early Triassic, as well as the contemporaneous rise in carbon dioxide, possible huge hydrogen sulfide flux as per papers like the Kump et.al. one from last year (I think?) and potential associated secondary effects of that. Basically, we have an oxygen lab for testing mass extinction kill mechanisms.

David and I are kindred spirits of a sort, being both not only astrobiologists and at least occasional users of leafy green substances (I don't really consider myself a stoner), we're both rock guitarists...

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Do not taunt Happy Fun Ball.

I think it is virtually certain the seas of Titan harbor volcanic vents. I would hesitate to risk even a nickel - or iron - they do not also harbor self replicating molecules. Life is so pernicious on earth I am convinced the dang stuff will eventually spring up anywhere given even a paltry billion to one opportunity. I just looked out the back window and observed my swimming pool, which is about 64% clorox by volume, has a noticeably green hue again.

Hilarious. Damned aliens. The first institution alien invaders target are the temples, then recording studios. Has anyone noticed how difficult it is to play MP3's backwards? The only reason aliens have not yet destroyed earth is they fear they have contracted rap - and are forbidden to return to their home world before discovering a cure.

What does Peter think about the big Antarctic crater that was recently discovered? I don't see how a disaster that huge could have been caused by anything BUT a massive bolide or other calamity from space. What else could make a nice promising planet go drastically wrong? Nobody was driving SUV's then, either.

Emotionally I prefer the bolide impact explanation because it's like the difference between being beaten up by a stranger and by your mother (Earth). I think a bolide could have caused the volcanism, which would have led to the other effects. I believe Mars must have been hit by something massive, which caused volcanoes and geological scars huger than anything in the solar system.

I got so obsessed with the Permian Extinction that after I watched War of the Worlds I wrote a SF story about how methane-breathing Aliens caused the extinction because they were trying to "xenoform" Earth.

http://www.geocities.com/shadow42.geo/7fingered.html

Peter Ward's book and the astrobiology articles about Titan inspired this story.

Leafy green stuff is great, and so is Rock guitar!!! (I used to play bass.)

__________________
"I am happy to report that once again the universe is doing just great, thank you, purring with perfection, ever-changing same as always. Light is still cruising along at 186,000 miles per second, and the expanding universe shows no signs of contracting. At this rate, it won't be long before they'll have to let the photon belt out another notch."
Swami Beyondananda's 2007 State of the Universe address

Yeah, stuff in the freezer eventually goes bad too.

Has anyone done an experiment, trying to replicate the cryovolcanic environment and seeing what grows?

__________________
"I am happy to report that once again the universe is doing just great, thank you, purring with perfection, ever-changing same as always. Light is still cruising along at 186,000 miles per second, and the expanding universe shows no signs of contracting. At this rate, it won't be long before they'll have to let the photon belt out another notch."
Swami Beyondananda's 2007 State of the Universe address