A moon of Saturn may have 'tropical' lakes

reply to post by PurpleChiten


Ok but you did not respond to my question. Water has many unique properties which allow for complex life. How would life be altered if only one property of water changed, if it sank when it froze (like almost all liquids do) rather than floated?

Originally posted by OccamsRazor04
reply to post by PurpleChiten

 

Ok but you did not respond to my question. Water has many unique properties which allow for complex life. How would life be altered if only one property of water changed, if it sank when it froze (like almost all liquids do) rather than floated?

It's a long, complicated answer and it's addressed in the link I gave you. Please check it and I'll be happy to discuss what you want afterwards.

Originally posted by OccamsRazor04
reply to post by PurpleChiten

 

Ok but you did not respond to my question. Water has many unique properties which allow for complex life. How would life be altered if only one property of water changed, if it sank when it froze (like almost all liquids do) rather than floated?

It's just really, really long... Here is a snippet of it that mentions the other possiblities but doesn't describe them in detail. They are described individually in the article. This is all hypothetical but they are looking at the possiblities that could exist, just as I said.

en.wikipedia.org...

In addition to carbon compounds, all currently known terrestrial life also requires water as a solvent. This has led to discussion about whether water is the only liquid capable of filling that role. The idea that an extraterrestrial life-form might be based on a solvent other than water has been taken seriously in recent scientific literature by the biochemist Steven Benner, and by the astrobiological committee chaired by John A. Baross. Solvents discussed by the Baross committee include ammonia, sulfuric acid, formamide, hydrocarbons, and (at temperatures much lower than Earth's) liquid nitrogen, or hydrogen in the form of a supercritical fluid.

reply to post by PurpleChiten


Yes, they are looking into it, but water is special and has many unique properties that none of those have which makes it ideally conducive for life. I believe it would be extraordinally unlikely that anything other than the simplest of lifeforms could exist with those solvents.

Originally posted by OccamsRazor04
reply to post by PurpleChiten

 

Yes, they are looking into it, but water is special and has many unique properties that none of those have which makes it ideally conducive for life. I believe it would be extraordinally unlikely that anything other than the simplest of lifeforms could exist with those solvents.

I would agree with that completely.
They would have to find one that was a polar molecule and behaved the way water does by expanding on freezing instead of contracting so it woud have the same properties ... or they would have to pick a gaseous solvent and processes that occured very differently than the way we understand them..

reply to post by PurpleChiten


I believe germanium and silicon are the only two solvents that are less dense as a solid than as a liquid, that would be a liquid at apropriate temperatures.

The idea of a gaseous solvent would be interesting, I imagine it would have to be a very dense gas, perhaps under some pressure? Definitely interesting, I wonder if there are any candidate gases or how it would work.

ETA: I do not think we will find life on another planet personally, especially sentient life that is vastly different than our own. I do find conjecture on the subject fascinating.

There was a paper written a few years back that noted the fact that hydrogen and acetylene in Titan's atmosphere disappears at the surface, prompting people to think of possible reasons for this.

The famed NASA astrobiologist Chris McKay has speculated one possible reason for this (although remember this is only speculation) may be that the hydrogen and acetylene is being used by life on Titan as a food source or for life processes:

One key finding comes from a paper online now in the journal Icarus that shows hydrogen molecules flowing down through Titan’s atmosphere and disappearing at the surface. Another paper online now in the Journal of Geophysical Research maps hydrocarbons on the Titan surface and finds a lack of acetylene.

This lack of acetylene is important because that chemical would likely be the best energy source for a methane-based life on Titan, said Chris McKay, an astrobiologist at NASA Ames Research Center, Moffett Field, Calif., who proposed a set of conditions necessary for this kind of methane-based life on Titan in 2005. One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. But McKay said the flow of hydrogen is even more critical because all of their proposed mechanisms involved the consumption of hydrogen....

...“We suggested hydrogen consumption because it’s the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth,” McKay said. “If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth.”

color emphasis mine


Source:
NASA Article: What is Consuming Hydrogen and Acetylene on Titan?



↓ ↓ Post continued below ↓ ↓ (too many characters for one post)

↑ ↑ Continued from above ↑ ↑


In another article, McKay once again discusses the possible biological explanations for the disappearance of hydrogen and acetylene at Titan's surface:

Recent results from the Cassini mission suggest that hydrogen and acetylene are depleted at the surface of Titan. Both results are still preliminary and the hydrogen loss in particular is the result of a computer calculation, and not a direct measurement. However the findings are interesting for astrobiology. Heather Smith and I, in a paper published 5 years ago (McKay and Smith, 2005) suggested that methane-based (rather than water-based) life – ie, organisms called methanogens -- on Titan could consume hydrogen, acetylene, and ethane...

...This is a still a long way from "evidence of life". However, it is extremely interesting.

Benner et al. (2004) first suggested that the liquid hydrocarbons on Titan could be the basis for life, playing the role that water does for life on Earth. Those researchers pointed out that "... in many senses, hydrocarbon solvents are better than water for managing complex organic chemical reactivity”. Two papers in 2005 followed up on this logic by computing the energy available for methanogenic life based on the consumption of both the organics in Titan's atmosphere along with the hydrogen in the atmosphere. Both papers made the case that H2 on Titan would play the role that O2 plays on Earth. On Earth organisms (like humans) can react O2 with organic material to derive energy for life's functions. On Titan organisms could react H2 with organic material to derive energy. The waste product of O2 metabolism on Earth is CO2 and H2O; on Titan the waste product of H2 metabolism would be CH4. As a result of the Cassini mission, there is now abundant evidence for CH4, even in liquid form, on Titan.

color emphasis mine

However, it is noted there could be other reasons for the depletion of hydrogen at the surface, other than life:

In conclusion, there are four possibilities for the recently reported findings, listed in order of their likely reality:

1. The determination that there is a strong flux of hydrogen into the surface is mistaken. It will be interesting to see if other researchers, in trying to duplicate Strobel's results, reach the same conclusion.

2. There is a physical process that is transporting H2 from the upper atmosphere into the lower atmosphere. One possibility is adsorption onto the solid organic atmospheric haze particles which eventually fall to the ground. However this would be a flux of H2, and not a net loss of H2.

3. If the loss of hydrogen at the surface is correct, the non-biological explanation requires that there be some sort of surface catalyst, presently unknown, that can mediate the hydrogenation reaction at 95 K, the temperature of the Titan surface. That would be quite interesting and a startling find although not as startling as the presence of life.

4. The depletion of hydrogen, acetylene, and ethane, is due to a new type of liquid-methane based life form as predicted.

Source:
Have we discovered evidence for life on Titan?



Here is a link to McKay's and Smith's 2005 paper in the science journal "Icarus" (although this is the abstract only -- the actual paper must be purchased):
Icarus Article: Possibilities for methanogenic life in liquid methane on the surface of Titan

and a link to the Icarus paper about Hydrogen loss that prompted this (again, only the paper's abstract):
Molecular hydrogen in Titan’s atmosphere: Implications of the measured tropospheric and thermospheric mole fractions

I doubt very much that Titan is the only moon in our solar system with an atmosphere, and suspect that earth was once a moon of Tiamat or Jupiter, herself.

Originally posted by Unity_99
I doubt very much that Titan is the only moon in our solar system with an atmosphere, and suspect that earth was once a moon of Tiamat or Jupiter, herself.

Titan is the only moon in our solar system with a substantial atmosphere.

It actually has more atmospheric pressure than the Earth or Mars:

Titan - pressure: 146.7 kPa

Earth - pressure: 101.325 kPa
Mars - pressure: 0.636 (0.4–0.87) kPa
Io - pressure: trace
Europa - pressure: trace
Ganymede - pressure: trace
Callisto - pressure: trace
Triton - pressure: trace

kPa = Kilo Pascals. 1 pound per square inch of pressure is equal to 98,066.5 or almost 1 kilo pascal.

Venus is 9.3 MPa (Million Pascals btw).

As for Earth having once been a moon of Jupiter or some fairy tale planet.....

Originally posted by Soylent Green Is People
There was a paper written a few years back that noted the fact that hydrogen and acetylene in Titan's atmosphere disappears at the surface, prompting people to think of possible reasons for this.

The famed NASA astrobiologist Chris McKay has speculated one possible reason for this (although remember this is only speculation) may be that the hydrogen and acetylene is being used by life on Titan as a food source or for life processes:

could be a matter of densities of gases/liquids, the more dense congregate at the bottom and it decreases as it goes up. Google "density column" for an explanation. Here's a very very generalized example

chemistry.about.com...

If there isn't a lot of movement in the atmosphere like we get from the Jet Stream and North Atlantic Current, the gases in the atmosphere could come into an equilibrium and they would separate according to density

Originally posted by PurpleChiten

Originally posted by Soylent Green Is People
There was a paper written a few years back that noted the fact that hydrogen and acetylene in Titan's atmosphere disappears at the surface, prompting people to think of possible reasons for this.

The famed NASA astrobiologist Chris McKay has speculated one possible reason for this (although remember this is only speculation) may be that the hydrogen and acetylene is being used by life on Titan as a food source or for life processes:

could be a matter of densities of gases/liquids, the more dense congregate at the bottom and it decreases as it goes up. Google "density column" for an explanation. Here's a very very generalized example

chemistry.about.com...

If there isn't a lot of movement in the atmosphere like we get from the Jet Stream and North Atlantic Current, the gases in the atmosphere could come into an equilibrium and they would separate according to density

edit on 15-6-2012 by PurpleChiten because: (no reason given)

I agree. Is it possible that this is evidence of life? Yes. Is it likely. No. Is it the most likely of unlikely reasons. No. At this point there are known processes that account for this and life is not needed to explain it. An interesting exercise of the mind, but its not really science.

Originally posted by OccamsRazor04

Originally posted by PurpleChiten

Originally posted by Soylent Green Is People
There was a paper written a few years back that noted the fact that hydrogen and acetylene in Titan's atmosphere disappears at the surface, prompting people to think of possible reasons for this.

The famed NASA astrobiologist Chris McKay has speculated one possible reason for this (although remember this is only speculation) may be that the hydrogen and acetylene is being used by life on Titan as a food source or for life processes:

could be a matter of densities of gases/liquids, the more dense congregate at the bottom and it decreases as it goes up. Google "density column" for an explanation. Here's a very very generalized example

chemistry.about.com...

If there isn't a lot of movement in the atmosphere like we get from the Jet Stream and North Atlantic Current, the gases in the atmosphere could come into an equilibrium and they would separate according to density

edit on 15-6-2012 by PurpleChiten because: (no reason given)

I agree. Is it possible that this is evidence of life? Yes. Is it likely. No. Is it the most likely of unlikely reasons. No. At this point there are known processes that account for this and life is not needed to explain it. An interesting exercise of the mind, but its not really science.

Just remember, although your moniker is often used to determine the simplest result, it doesn't determine all results and all results must be taken into account. Every now and then, those multiple hypothesis all turn out to be true

reply to post by PurpleChiten


When we have a viable explanation why would you consider an exotic one? Thats not science. I am sure you can agree with me.

As I said it is possible, but beyond an exercize of thought, its silly to seriously think about life being responsible when there are testable alternatives that we know would be responsible. That is not science.

reply to post by eriktheawful


Only if you believe their lies and magic conjuring skills. Its not only NOT the only moon with an atmosphere, but we're not the only planet. This solar system is populated. I know there is a channel thing going on, ie. we're in a low frequency denser layer of reality, for in the Heaven(s), (and no heaven isn't boring) and its Schools, when the birds leave the nest to learn more, and grow their soul orbs bigger, learning Love and Equality, they tend to have Family groupings with those of similar frequency of thought. So on our channel, 1 out of infinite possibilities, we see alot less. But even here, they are conducting alot of secret space programs and mining already, co-op with ETs that they are working with and for. That is truth whether or not people live with their heads buried in the sand.

Even in our channel.

Originally posted by Unity_99
reply to post by eriktheawful

 

Only if you believe their lies and magic conjuring skills. Its not only NOT the only moon with an atmosphere, but we're not the only planet. This solar system is populated. I know there is a channel thing going on, ie. we're in a low frequency denser layer of reality, for in the Heaven(s), (and no heaven isn't boring) and its Schools, when the birds leave the nest to learn more, and grow their soul orbs bigger, learning Love and Equality, they tend to have Family groupings with those of similar frequency of thought. So on our channel, 1 out of infinite possibilities, we see alot less. But even here, they are conducting alot of secret space programs and mining already, co-op with ETs that they are working with and for. That is truth whether or not people live with their heads buried in the sand.

Even in our channel.

Again, no one said that it was the ONLY moon with an atmosphere.

Nor did anyone say that Earth is the only planet.

Originally posted by OccamsRazor04
reply to post by PurpleChiten

 

When we have a viable explanation why would you consider an exotic one? Thats not science. I am sure you can agree with me.

As I said it is possible, but beyond an exercize of thought, its silly to seriously think about life being responsible when there are testable alternatives that we know would be responsible. That is not science.

No, that's the science to explain what we are already experiencing, deductive reasoning. We're speaking of science being used to explore what else is possible, inductive reasoning. Both forms of reasoning are "science" but one is used for discovery, the other for understanding what was discovered.

Originally posted by eriktheawful

Originally posted by Unity_99
reply to post by eriktheawful

 

Only if you believe their lies and magic conjuring skills. Its not only NOT the only moon with an atmosphere, but we're not the only planet. This solar system is populated. I know there is a channel thing going on, ie. we're in a low frequency denser layer of reality, for in the Heaven(s), (and no heaven isn't boring) and its Schools, when the birds leave the nest to learn more, and grow their soul orbs bigger, learning Love and Equality, they tend to have Family groupings with those of similar frequency of thought. So on our channel, 1 out of infinite possibilities, we see alot less. But even here, they are conducting alot of secret space programs and mining already, co-op with ETs that they are working with and for. That is truth whether or not people live with their heads buried in the sand.

Even in our channel.

Again, no one said that it was the ONLY moon with an atmosphere.

Nor did anyone say that Earth is the only planet.

People like to make strawman arguments when it comes to showing how "evil" TPTB are. Mainstream scientists have told us about many bodies with atmospheres, some within our solar system and some outside our solar system. The idea that other celestial bodies have atmospheres is not being hidden from us.

Pluto, for example, is thought by mainstream science to have an atmosphere during the decades-long "summer season" (when Pluto is closer to the sun along its 248 earth-year orbit), but it is thought that the atmosphere freezes and drops to Pluto's surface during the decades-long winter season (when Pluto is farther from the sun).

Originally posted by fictitious
Thanks for sharing. This is pretty cool. I wish they would post the pictures they studied to come up with the theory.

They say it rains and has methane lakes. So I'm assuming it only rains methane? Very interesting.

And it rains in slow motion up there. Pretty cool!

Originally posted by PurpleChiten

Originally posted by OccamsRazor04
reply to post by PurpleChiten

 

When we have a viable explanation why would you consider an exotic one? Thats not science. I am sure you can agree with me.

As I said it is possible, but beyond an exercize of thought, its silly to seriously think about life being responsible when there are testable alternatives that we know would be responsible. That is not science.

No, that's the science to explain what we are already experiencing, deductive reasoning. We're speaking of science being used to explore what else is possible, inductive reasoning. Both forms of reasoning are "science" but one is used for discovery, the other for understanding what was discovered.

Right. Ignoring the known and mundane explanations for a phenomenon (such as the disappearance of hydrogen and acetylene at Titan's surface) is wrong and "bad science", but there is nothing wrong with considering other "unknown" explanations. After all, that's what science is all about.

One of purpose of science is to ask "what if". There is nothing scientifically wrong with hypothesizing that the reason for this hydrogen flux may possibly be that the hydrogen is being consumed by living organisms. Considering that hypothesis does not make it equally like as the more "known" explanations, but that doesn't mean it shouldn't be considered at all. That is a hypothesis that would then need to be (somehow) tested.

In fact, it would be just as wrong if science ignored the "life" explanation as it would be if they ignored the more prosaic explanations. It is a hypothesis that deserves some scientific consideration.