Is the Jury back on Titan surface liquid?

[centsworth_II]

There is NO life [KNOWN]without liquid water..... THAT would be fact.<br /><br />Life is possible without liquid water..... THAT would be speculation.<br /><br /> <div class="Discussion_UserSignature"> </div>

 

[Philotas]

A fact is proven true. It isn`t proved that water is necessary for life; what`s proved is that water can support life. <br />No one has ever looked for life where it could exist without using water as liquid, hence you cannot rule it out. <div class="Discussion_UserSignature"> </div>

 

[unlearningthemistakes]

I was hoping philotas would answer his own riddle.<br /><br /><br />P.S. we share the same sentiments. <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[unlearningthemistakes]

<font color="yellow">It isn`t proved that water is necessary for life; what`s proved is that water can support life.</font><br /><br />just reverse the question around:<br /><br />so without water, life could be possible?<br />what else aside from water can support life just like a water does? <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[Philotas]

<font color="yellow">so without water, life could be possible? <br />what else aside from water can support life just like a water does?</font><br /><br />It could, we don`t know.<br /><br />Other possible liquids are: hydrocarbons,ammonia, sulfur acid, nitrogen, argon, neon, hydrazine and hydrogen. <div class="Discussion_UserSignature"> </div>

 

[unlearningthemistakes]

Is it safe to assume that there is nothing else aside from h2O that can support life just like the way it does the way we see it NOW? (let us count by what we have in our hands this day----tomorrow is for tomorrow---this day is for this day)<br /><br /><br />P.S.perhaps is an answer not to be taken... <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[silylene old]

Well, we had a nice discussion on this same subject of water being the medium for life, back before the SDC meltdown. Too bad it is lost.<br /><br />To recap some of the points I made in the prior (lost forever) thread:<br /><br />Why is water the "ideal" medium for life?<br /><i>In approximate order of most to least important reasons,</i><br />1. Because it is a liquid in the temperature range that corresponds to the activation energy for a huge variety of organic chemical reactions. <br />2. It's a very good solvent for most ionic and polar organic compounds, and also for dissolved gases. <br />3. Hydrogen bonding allows water as a solvent to act as an active media to participate and facilitate many organic reactions. <br />4. It is abundant in the universe and on earth. <br />5. Water's highly polar nature allows it to readily form lipid membranes with non-polar higher MW molecules. In terran life, lipid membranes form cell walls and organelle walls. It is an absolute requirement for life that the cellular biochemistry has to be isolated from the general liquid by some sort of a barrier in order that the concentration of biomolecules is large, and deleterious molecules are eliminated, so that the chemical reactions of life can proceed without deleterious side reactions or dilution.<br />6. Water has a rather low viscosity. This helps biochemical reactions to proceed faster, often without being limited by diffusion of reactants. Also important for fluids flowing through very narrow vessels.<br />7. Water floats when it freezes. This tends to insulate the liquid below from freezing. This behavior isn't a necessity for life or its evolution, but I think it helps. (On the other hand, because water expands on freezing, it ruptures cells. With a solvent that shrinks, this would be avoided.)<br /><br />++++<br /><br />There are other liquids which may also be good for facilitating life, in a different world with a completely different biochemistry. I doubt they these alternati <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[JonClarke]

"A bio-chemic experiment showed that sugar like molecules found themselves quite comfortable in liquid nitrogen. However, only the molecules based on silicon "thrived", the ones based on carbon did not work out very well. Same is for the opposite: silcon molecules doesn`t do it well in water, while carbons do."<br /><br />Interesting. Do you have a source for this? <br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[telfrow]

<i>There is NO life [KNOWN] without liquid water..... THAT would be fact. <br />Life is possible without liquid water..... THAT would be speculation.</i><br /><br />That pretty much sums it up, Centsworth. <img src="/images/icons/wink.gif" /><br /> <div class="Discussion_UserSignature"> <strong><font color="#3366ff">Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild.</font> - <font color="#3366ff"><em>Tennyson</em></font></strong> </div>

 

[jatslo]

What? There are plenty of organics that do not need water, and petroleum is a good place to start looking.

 

[bonzelite]

i will contribute to the SDC Meltdown further:<br /><br />life may be possible without water. <br /><br />we are the needle in the giant haystack. i am sure there are millions of other planets that have different chemical conditions for life. <br /><br />at present, it is FACT that water must exist for life in this world. that is fact. <br />but to speculate about other possible lifeforms without water is NOT a "meltdown." <br /><br />

 

[mikeemmert]

Hi, steve;<br /><br />If I make a claim that there may be some evidence that there is life based on, say, methane, then that does NOT eliminate the possibility of life based on water, ethane, phosphine, hydroflouric acid, or any other liquid. That is a logical fallacy.<br /><br />"...without a shred of evidence..."<br /><br />There are two lines of evidence here. One, mentioned in my post and taken from one of the links posted in this thread, is that pyrolysis (heating) of the aerosols of Titan produces ammonia and cyanide. Since this is an unexpected reaction, one may propose possible reactions, and one of those is some kind of life form.<br /><br />The other line is that there is methane present in Titan's atmosphere, and that it is known that exposing methane to ultraviolet radiation decomposes the methane. So far, no simple means of reconstituting it have been found. So some unknown mechanism is at work. Some lifeform is one possible answer (though not the only one, of course).<br /><br />"unsupported by ANY real, existing evidence"<br /><br />What Huygens and Cassini have been unable to find is another source for the methane. So far, no volcanism has been detected. They haven't found any tectonism.<br /><br />"There is NO life without liquid water. Basic fact."<br /><br />The only life found in the universe so far (proving beyond a shadow of a doubt that life does indeed exist) is on Earth, where overwhelming prescence of water crowds out any other possible liquid for life to base itself on.<br /><br />That was the whole point of sending a probe to Titan, is to examine a world where some other liquid might be predominant. Unfortunately limitations in technology limited the instruments that could be brought to bear on the subject. For instance, the aerosols were not examined under a microscope. They were simply heated. Since unexpected compounds were given off, further investigation is warranted. The reactions which produced ammonia and cyanide need to be identified

 

[jatslo]

Water is not required; only minerals are required, and that is a fact. Water helps break down the minerals for consumption, but so do other solubles. Have you heard of digestive juices, and the bacterium that thrive in the acids? The juices are not required, but aid absorbtion rates by breaking down the chemical bonds that bind minerals. Microbs turn oil into water, but water is not required, NOT REQUIRED.<br /><br />It’s an unforgettable memory. After the first Gulf War, millions saw on TV the image of a bird drenched in oil — the result of a massive oil spill. The image triggered a race among scientists to find a solution for oil degradation. Efforts began in India as well and the government funded four groups in Delhi, Nagpur, Goa and Pune to come out with a solution. More than a decade later it seems that Dr Banwari Lal from The Energy and Resources Institute (TERI) has the solution.<br /><br />The diminutive microbiology graduate from Rajasthan University now has two technologies — one for eating up oil and oily sludge and the second one for making sick oil wells performing once again.<br /><br />On February 27, he received the National Bioscience Award and the technology was shortlisted for the World Technology Award. Holder of two patents, Dr Lal spoke to Deccan Herald about his work. <br /><br />Excerpts:-<br /><br />Q: Tell us about your work on the oil-zapper. When did you start it and how did you achieve the initial success? <br />The project on bioremediation started in 1991 after the first Gulf War with support from the Department of Biotechnology (DBT). Four groups were given projects to identify oil-eating microbe from nature and develop a commercially viable bioremediation technology. During that programme we have been able to identify a microbial cocktail that can degrade all four types of crude oil fractions — saturated hydrocarbons, aromatic hydrocarbons, sulphur and nitrogen containing fractions and asphaltanes and resins. All fractions were degraded to car

 

[bonzelite]

yes, if a liquid medium predominates that is not water, then if life were to arise at all, then it would emerge in the suspension medium of that specific world's environmental characteristics. <br /><br />just like there are species of animals on the galapagos islands that exist nowhere else on this planet, as they arose from a very niche-specific set of environmental parameters, life ITSELF may do the same thing. this is highly plausible. <br /><br />insofar as the pyrolosis of the titan atmospheric samples, essentially you have a sort of surrogate metabolism in that heating, giving off the waste byproducts of ammonia and cyanide. as is said, the results were alarming and unexpected, and of an unknown reason.

 

[jatslo]

Bug excretions are diverse; not only that, but bugs/fish can make there own light and heat, if heat is required, which I don't think it is. Hell, bugs can terraform an entire planet very quickly. For example, bugs can convert Titan into a water planet by breaking down the elements, like methane.

 

[newtonian]

Dragon04 - You posted negatively concerning the cold temperatures at Titan (-175C? 95K?) and the origin of life:<br /><br />"the proper chemical processes being able to get life going at those temperatures in the first place."<br /><br />Can you specify what chemical processes you are referring to?<br /><br />Some prebiotic molecules prefer cold overall temperatures to be stable - at room temperature many complex prebiotic molecules are unstable - thus the need for refrigerators for biotic foods! <br /> <br />I am not disagreeing with you, btw. Just inquiring about details.

 

[unlearningthemistakes]

well pointed exactly!! <img src="/images/icons/wink.gif" /><br /><br /> <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[newtonian]

JonClarke - You posted concerning water and life:<br /><br />"The chemists among us can correct me on this, but water is an ideal solvent. It is stable over a wide temperature range. Water is common in the universe, more common that either methane or ammonia. It is also liquid over a temperature range that allows both complex organic molecules and rapid chemical reactions."<br /><br />The problem is you don't specify the chemical reactions, and if you consider details you will find the scenario does not make sense. <br /><br />For example, HCN (Hydrogen Cyanide) has been detected on Titan, and HCN is thought to be an important starting chemical for synthesis of life - especially amino acids to polymers (dipeptides to polypeptides) to statistical proteins ("junk" proteins lacking informational input - contrast proteins synthesized by life due to informational input).<br /><br />Water is, as you say, a good solvent and reaction medium.<br /><br />However, water also reacts with HCN and the many other chemicals on pathways to complex prebiotic molecules including amino acids, purines, pyrimidines, nitriles, aminonitriles, porphyrins and other polymers.<br /><br />For example, water reacts with HCN directly:<br /><br />H2O + HCN yields Formamide (H3CNO [carbon's 4 bonds: one to one hydrogen; one to NH2; two to one Oxygen])<br /><br />[Note: in HCN the carbon has a triple bond with Nitrogen; in Formamide H2O is added to this triple bond.]<br /><br />Then formamide also reacts with water:<br /><br />H3CNO + H2O yields Formic Acid (HCOOH) + NH3 (ammonia).<br /><br />I will post only on one of the many 2nd steps from HCN to precursor to life polymers (a polymer is simply a combination of ingredients to form a more complex molecule).<br /><br />Namely, the chemical pathway from HCN to cyanamide to dicyandiamide to Amino acids (also to purines, porphyrins, and other polymers).<br /><br />I.e. the 2nd step from HCN to cyanamide (to dicyandiamide is a third step, btw.)<br /><br />Cyanamide, like many othe

 

[newtonian]

Philotas - I am not saying God could not create life using other matter based informational molecules (compare computers, for example, by human creators).<br /><br />Silicon is favored because of its chemical properties.<br /><br />I will post more on this later, but there are drawbacks for Silicon compared with carbon.

 

[bad_drawing]

I believe the "Meltdown" that Silylene was talking about was an event in the past when the SDC message boards went down and many threads were lost. I don't believe it was intended as an assault on the conversation at hand. <br /><br />At least thats my impression of what happend during the meltdown based on other threads that mention it too. Somebody correct me if I'm wrong. <br />

 

[newtonian]

Philotas - OK, in your post can you link to the experiment or post more detail? Were those sugar-like molecules silicon based rather than carbon based?<br /><br />Meanwhile, here are some reasons why carbon based lilfe is far easier to create (though still difficult) than silicon based life:<br /><br />"Nitrogen (N) and boron (B), elements in the second period of the Periodic Table, are similar in size to carbon. Silicon, like carbon, has four valence electrons. These three elements might be expected to bond in a similar manner to carbon and to form a similar number of compounds, but they do not. Each may form carbonlike compounds, but none has carbon's combination of valence and inner electrons. Their carbonlike compounds are often short-lived and unstable." - "The World of Science," 1991, Volume 14, page 15.<br /><br />Now, liquid nitrogen, as in your post, is very cold - and most molecules are far more stable when in a freezer - so the result you refer to is not totally unexpected - however, can you specify exactly what sugar-like molecules?<br /><br />For more detail on why silicon based life is not likely:<br /><br />"Since both silicon and carbon are members of Group IV of the periodic table, a resemblance between the chemistry of these two elements is to be expected. Silicon, like carbon, prefers to use sp3 alpha bonding in most of its compounds (Table 4.7). There is a wide range of structural similarity between the compounds of silicon and carbon with regard to alpha bonding and molecular geometry. Tetravalent silicon derivatives are configurationally stable, and examples of optical and geometrical isomerism attributable to the silicon atom are commonplace. A striking difference in the fundamental chemistry of the two elements is seen in their bond strengths: The carbon-carbon bond is quite strong (82.6 kcal/mole), the silicon-silicon bond is relatively weak (53 kcal/mole). The silicon-hydrogen bond is also weaker than the carbon-hydrogen bond. Consequent

 

[bad_drawing]

"There is NO life [KNOWN]without liquid water..... THAT would be fact. <br /><br />Life is possible without liquid water..... THAT would be speculation."<br /><br />I agree with this as a logically true statement. The beauty of it is that all of the things we accept as true these days began with speculation. I understand the sentiments of some here that its only natural that we base all models of life and searches for life on water, since its all we know, but that doesn't rule out other possibilities... even if in the form of speculation. I'm not ready to fit any square pegs in round holes for it... but what a mindbending discovery that would be.<br /><br />I look at the Mars data we've gotten from our extensive array of tools on and around it, and as a host planet for life, I just can't wrap my head around it. If its there I have a feeling that it is in small pockets. However, the data coming in about Titan is giving it a definate "Hmmm factor". Life? Who knows. But it seems to be getting more and more intersting... even if abiotic it would be cool to know what does explain the things we're seeing there.

 

[newtonian]

bad_drawing - Well, I share your interest in the discoveries. I am simply trying to reign in the speculations to conform to known facts - as in the above facts in chemistry.<br /><br />I certainly do not claim God could not have created some form of life on Titan or elsewhere in our solar system.<br /><br />We certainly have had "mind-bending" discoveries of different, unexpected, forms of life on earth - as in extremophiles!

 

[bad_drawing]

I suppose what I'm trying to say with my Mars/Titan comparison is that it seems like on Mars.... we really want to find life... and when the results come in from various locations that make it inconclusive (with a leaning towards doubtful) we speculate other locations or other ways life could survive there. This is understandable because life is amazing and once it gets going, it will find the niche where it can thrive. But still, with Mars... we seem to want to believe there's life there even if a lot of the data pretty much says "nah"... Meanwhile Titan almost seems to have smacked us in the head with some bizarre results. <br /><br />I wonder if Huygens landed in greenland in a location with no visible sign of life, would its sensors be able to detect life as we know it? I doubt it. The data would probably suggest that conditions are good, and there's an excess of this compound and that compound that point to life, but mostly what it would say is "Very Interesting... Intersting enough to warrant a more in depth mission." And thats where I see Huygens as a huge success that needs to be followed up on.

 

[silylene old]

Newtonian....sort of. That reference you cite is a bit dated. <img src="/images/icons/smile.gif" /><br /><br />R3Si-OH (silanols) do form strong very hydrogen bonds. They just tend to be rather unstable to condenstaion reactions to form R3Si-O-SiR3. However, silanols can be quite stable for years in the right solvent and pH ! For example, silicate nanoparticles ( a colloidal suspension) of size 2nm to 20nm diameter terminated with a Si-OH surface are metastable for years in water/alcohol blends at pH4. Silicate nanoparticles are hyperbranched polymers...<br /><br />Si-OH terminated silsequioxanes (SSQ, another type of branched polymer in a ladder-like configuration) are also rather metastable for years in the right solvent and pH.<br /><br />I do think that organo-silicate colloids and organo-SSQs are a little bit intriguing from a point of view of speculating on alternate biochemistries.<br /><br />I also one to correct/add a couple of other points:<br />- One can also make long-chain polysilanes (R1R2Si)n with MWs over 300K (although the synthesis is a bit complex for a biochemical reaction!).<br />- One can make Si=Si species in the absence of O2.<br />- Si-Si bonds are photochemically active in the UV<br />- The Si-O-Si linkage is not irreversable. In the presence of fluoride and at the right pH, it is possible to cleave Si-O bonds at mild temperatures.<br /><br />You are right that silicon's tendency to preferentially oxidize makes imagining possible Si based biochemistries rather challenging. Agreed! <br /><br />The overall gist is:<br />1) No matter what, silicon-based chemistry will never offer the variety of reactions possible in carbon chemistry. But even while I do believe the chance for Si-based lifeforms is quite remote, I can imagine just enough chemical variety to prevent me from claiming that silicon-based life is utterly impossible.<br />2) Organosilicate nanoparticle colloidal suspensions and SSQ's are quite complex and at least offer a quite variety of str <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>