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posted by martyb on Saturday February 28 2015, @03:21PM   Printer-friendly
from the not-very-useful—-they'll-just-chill-out dept.

We had two submissions on non-water-based life forms; the study and images are available at: https://cornell.box.com/azotosome

The search for extra-terrestrial life focuses quite heavily on the presence of liquid water. That's because all life on earth depends on water, using it as a medium for all cells, and an ingredient for many biological processes.

Is life without water possible? A chemical engineer and others at Cornell University devised a hypothetical model for life that could instead use liquid methane as its medium, opening more possibilities for simple life on Titan and on other cold moons and planets.

A new type of methane-based, oxygen-free life form that can metabolize and reproduce similar to life on Earth has been modeled by a team of Cornell University researchers.

http://phys.org/news/2015-02-life-saturn-moon-titan.html

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  • (Score: 2, Insightful) by Anonymous Coward on Saturday February 28 2015, @04:07PM

    by Anonymous Coward on Saturday February 28 2015, @04:07PM (#151093)

    I find it ignorant to operate on the premise that life can only form based on what holds true on Earth. It is quite similar to the view that Earth is the center of the universe. Life, as we know it on Earth, is only possible when ... however, would be an accurate statement.

    • (Score: 2) by bob_super on Saturday February 28 2015, @05:23PM

      by bob_super (1357) on Saturday February 28 2015, @05:23PM (#151129)

      I agree with you and it really annoys me too. I am sure that there is "life" elsewhere in the universe, the question is how much looks even remotely like what we're used to.

      However, until we see liquid-methane-ocean killer whales (you're a tasty frozen snack) or stone-based trolls ("it's got no weak points, it's made of rock!") roaming on another planet, it's really hard to know what to look for, to find that non-water/carbon life.

      • (Score: 0) by Anonymous Coward on Sunday March 01 2015, @05:40PM

        by Anonymous Coward on Sunday March 01 2015, @05:40PM (#151577)
        How about life in the Sun or other stars? There seems a fair bit of activity in stars. Won't be like our sort of life. But couldn't there be "order from disorder", reproduction, evolution etc.

        Very fancy eddies in the river of entropy...
    • (Score: 1) by khallow on Saturday February 28 2015, @07:12PM

      by khallow (3766) Subscriber Badge on Saturday February 28 2015, @07:12PM (#151161) Journal

      I find it ignorant to operate on the premise that life can only form based on what holds true on Earth.

      It's a good thing then that this research pushes that envelope of comfort then. Cryogenic methane chemistry is a good starting point for a radical departure.

    • (Score: 3, Interesting) by Hairyfeet on Sunday March 01 2015, @12:13AM

      by Hairyfeet (75) <{bassbeast1968} {at} {gmail.com}> on Sunday March 01 2015, @12:13AM (#151299) Journal

      I believe it was Neil deGrasse Tyson who said it was NOT merely basing it on what has come before here on earth, but instead basing it on what it the most common and abundant elements in the known universe. If you look at the most common elements with the exception of helium (which is inert) you have hydrogen, oxygen, and carbon, what we consider "the building blocks of life".

      Could other forms that live on other things exist? Sure it can, look at the methane worms that live deep in the ocean, but it'll have an uphill struggle when it comes to us detecting it because 1.- So far models have shown that something that lived on those chemicals would most likely be like the worms, living in deep dark places we cannot reach, and 2.- Due to the absence of an abundant source of energy (like the sun) to generate plenty of food the odds of it ever evolving into anything larger than worms is really rather low. We can't even say that it could evolve as far as the creatures on the bottom of our own ocean because those creatures, despite never having seen the sun, are in fact getting energy from it as they feed on the constant rain of particles generating from the light zones that constantly rains down upon them.

      So I wouldn't call it being "earth centric" so much as trying to cast as wide a net as possible and therefor looking for what is possible using the most abundant elements we know of. That said i would be happy to support shooting a probe below the ice of Europa, if there is any place in our system that could have completely alien life? It would most likely be there.

      --
      ACs are never seen so don't bother. Always ready to show SJWs for the racists they are.
      • (Score: 2) by Immerman on Monday March 02 2015, @01:22AM

        by Immerman (3985) on Monday March 02 2015, @01:22AM (#151695)

        Mostly those deep-sea worms feed on bacteria which in turn feed on the chemicals coming from deep-sea volcanic vents. The source of energy is latent heat+fissionable material in the Earth's core - nothing to do with the sun at all. And that was probably the case with early life on Earth as well - until blue-green algae developed photosynthesis and poisoned the planet with oxygen, chemovores were pretty much the only route by which energy entered the ecosystem. And a heated core doesn't seem to be a rarity.

        As for the CHON building blocks of life - that's quite right, the common elements are the ones most likely to be the basis for life - but there's nothing specific about oxygen-breathing, water-based life in that claim. Methane, ammonia, etc. are also common arrangements of CHON. And thanks to these researchers we now know that acrylonitrile (which is present in Titan's atmosphere) and other hydrocarbons can form cell walls that function much like our own, except at the cryogenic temperatures present in a liquid methane ocean.

        • (Score: 2) by Hairyfeet on Monday March 02 2015, @01:47AM

          by Hairyfeet (75) <{bassbeast1968} {at} {gmail.com}> on Monday March 02 2015, @01:47AM (#151699) Journal

          I'm sorry if I didn't make myself clear, I was NOT talking about the ammonia worms needing the sun, I was pointing out we can't even assume that they would evolve like deep sea life has as even the deep sea evolved creatures (like flatfish and crabs) get energy from the light from falling debris.

          And again I didn't say there was anything special, simply that with a limited budget and no ability to scan those deep areas of deep space objects? The most likely to return a positive given the tech we have is to target CHON, since that is most abundant.

          --
          ACs are never seen so don't bother. Always ready to show SJWs for the racists they are.
  • (Score: 3, Informative) by wonkey_monkey on Saturday February 28 2015, @04:09PM

    by wonkey_monkey (279) on Saturday February 28 2015, @04:09PM (#151095) Homepage

    That's because all life on earth

    Not sure if that's just a typo, or what, but I've seen the tendency is withold our planet's capital E before. What's that about? All the other planets get a capital letter!

    "earth" is the stuff plants grow in. "Earth" is the planet we live on.

    --
    systemd is Roko's Basilisk
    • (Score: 1) by dry on Sunday March 01 2015, @01:08AM

      by dry (223) on Sunday March 01 2015, @01:08AM (#151342) Journal

      Maybe he has a keyboard like mine where it seems the shift keys need twice as much pressure as all the others.
      I'm continuously having to go back and capitalize words that I thought I'd capitalized.

  • (Score: 2, Insightful) by Anonymous Coward on Saturday February 28 2015, @04:13PM

    by Anonymous Coward on Saturday February 28 2015, @04:13PM (#151098)

    Nothing like the Miller-Urey experiment has ever produced something as complicated as the phospholipid bilayer. Hopefully a simulation can estimate how likely it is for an "azotosome" to form in a hydrocarbon lake.

    What if the azotosome cannot be synthesized by nature? Back to looking for warm watery planets.

    • (Score: 1) by khallow on Saturday February 28 2015, @07:15PM

      by khallow (3766) Subscriber Badge on Saturday February 28 2015, @07:15PM (#151162) Journal

      What if the azotosome cannot be synthesized by nature?

      It still might be synthesizeable by something which can be synthesized abiotically in a hydrocarbon lake.

    • (Score: 3, Interesting) by fritsd on Saturday February 28 2015, @07:35PM

      by fritsd (4586) on Saturday February 28 2015, @07:35PM (#151172) Journal

      While it's true that the Miller-Urey experiment didn't come alive and bite its caretakers, it was only a small flask. If you repeat it on a planetary scale you'll get a gain of more than ten orders of magnitude. (I dunno, how much bigger are the oceans compared to that bottle??) Also the timescale of the experiment was a few decades IIRC, so you can add 5 orders of magnitude and see what you can get in 1 million years. If those vesicles or what you call them are relatively stable then you'll get more of them over time upto a saturation point. If the inside of some of the vesicles causes them to be more stable, or to split into two vesicles, etc. then that pattern of organization endures even more easily.

      Avogadro's number is 10^23, so even extremely small likelihoods of success in assembling RNA or an azotosome will occur randomly as long as you wait long enough and your planet is large enough to do the experiment in parallel.

      Actually I'm talking nonsense here a bit, because of course Avogadro's number was already incorporated in the original experiment. But what if it was *almost* enough and needed just a boost of a factor million or so.

      As molecules get larger, the "conformation space" of their internal angles also becomes more complex rapidly (curse of dimensionality) so you'll need more and more time for them to fold "properly" without help.

      Existing biomolecules such as enzymes and DNA have extremely nifty schemes to change that near infinite conformation space to something like folding a T-shirt or unzipping a zipper, but they are the end-product of a very long evolution.

      If you don't know much about biochemistry and you'd like to learn more about the fascinating stuff that can be done with self-replicating molecules such as DNA, read this: http://en.wikipedia.org/wiki/DNA_polymerase [wikipedia.org] (the pictures show that it would takes a lot of time and luck to assemble this enzyme from scratch :-) ), or this: http://en.wikipedia.org/wiki/Polymerase_chain_reaction [wikipedia.org]

    • (Score: 2) by Runaway1956 on Saturday February 28 2015, @07:58PM

      by Runaway1956 (2926) Subscriber Badge on Saturday February 28 2015, @07:58PM (#151179) Journal

      I think that the underlying point of the article is, if/when we find extraterrestrial life, it may not be like life on earth.

      The authors are looking at methane creatures, because that is the easiest alternative to imagine. But - they are still searching close to home.

      What is to say that there must be an azotosome? What if it's unnecessary? What if, when we finally stand face-to-whatever with an alien life form, we don't even recognize it as life? It simply doesn't meet ANY of our expected criteria!

      • (Score: 0) by Anonymous Coward on Sunday March 01 2015, @12:25AM

        by Anonymous Coward on Sunday March 01 2015, @12:25AM (#151307)

        I want it to be true, I'm just really skeptical. If the azotosome is viable, could it develop on Earth? Are we fracking azotosome life right now? Or does it require liquid methane oceans...

        I think we are setting ourselves up to be disappointed when we scour the cold bodies and under-ice oceans of this solar system and find nothing. Chances are we will find life by finding an Earth-like atmosphere and vegetation on a nearby exoplanet using JWST or one of Hubble's next next successors. We know that many stars appear to have an exoplanet in the habitable zone, including red dwarf stars. We have a growing list of confirmed and candidate exoplanets. We just need a bigger scope.

  • (Score: 5, Funny) by Nuke on Saturday February 28 2015, @04:27PM

    by Nuke (3162) on Saturday February 28 2015, @04:27PM (#151107)

    Is life without water possible?

    Life, but not as we know it.

  • (Score: 2) by darkfeline on Saturday February 28 2015, @06:11PM

    by darkfeline (1030) on Saturday February 28 2015, @06:11PM (#151142) Homepage

    I mean, the main role water plays is transportation in large organisms, right? (Disclaimer, I'm not a biologist) Blood for transporting nutrients and oxygen, urine for removing waste, I guess there's sweat too for cooling off. That's about it though. So long has you can replace these systems with some other machinery and/or substance, then life can operate much the same.

    Now, after I write this I realize that water is pretty damn convenient. It's a liquid, first and foremost, and it's "the universal solvent", allowing it to act as transportation very well. Even so, there's no physical reason why you MUST have water.

    --
    Join the SDF Public Access UNIX System today!
    • (Score: 3, Informative) by gnuman on Saturday February 28 2015, @06:48PM

      by gnuman (5013) on Saturday February 28 2015, @06:48PM (#151154)

      There are 2 things that are really important about water:

          1. water is a solvent for stuff life on earth uses
          2. ice floats

      You see, if ice did not float (ie. did not expand on freezing), then stuff would freeze from the bottom up which could be an issue if you don't want to be frozen.

      For multicellular life on earth to exist, oxygen is really important. If it wasn't for oxygen, like would exist like it did for the first 4 billion years - as single cell organisms. We only had multicellular life since the Great Oxygenation Event finished - about 600 million years ago. That was a "terraforming" event which "only" took 2-3 billion years!!

      http://en.wikipedia.org/wiki/Great_Oxygenation_Event [wikipedia.org]

      • (Score: 2) by Immerman on Monday March 02 2015, @01:35AM

        by Immerman (3985) on Monday March 02 2015, @01:35AM (#151697)

        You missed the important bit about floating ice - it produces a thermal barrier on the surface. Also water has an uncommon property that from about 2C (4?) it begins to expand when cooled further. Between that and the fact that ice floats you have a near-total shutdown of vertical mixing once the surface cools near the freezing point.

        But really, the reason why that's important at all is because Earth's surface temperature is constantly cycling near the freezing point - if the planet averaged 30C warmer, ice would be nearly unheard of, and boiling would still be vanishingly uncommon, so those interesting low-temperature properties would be mostly irrelevant. Of course methane only has a ~21C window at which it's liquid, (-182.5C to -161.49), so unless it has similarly curious properties it's probably going to be a rough ride for any protolife.

    • (Score: 2) by c0lo on Saturday February 28 2015, @09:34PM

      by c0lo (156) Subscriber Badge on Saturday February 28 2015, @09:34PM (#151217) Journal

      Even so, there's no physical reason why you MUST have water.

      You mean apart from max specific heat capacity (which guarantees longer availability of energy [wikipedia.org] for reactions [wikipedia.org]) and lesser density of the ice (which guarantees further isolation of the "solvation layer" from an energy loss)?

      Discounting them, yeah, there's nothing special about water.

      --
      https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
    • (Score: 2, Interesting) by VortexCortex on Sunday March 01 2015, @02:59AM

      by VortexCortex (4067) on Sunday March 01 2015, @02:59AM (#151389)

      The role that water plays in the chemistry of life within cells is also very important. Instead of writing about cellular microbiology, I'll simply link you to a visualization of the sub-cellular actions of 'white blood cells' locating sites of inflammation. [youtube.com]

      The all important water has been made clear in these visual animations. [youtube.com] Note that even here on Earth some bacteria have learned to metabolize iron and sulphur [wikipedia.org] in a short period of time, but we've found none that make do without water (which could very well be due to environment and our distance from our sun).

      Not to say that other substances could not replace water, just that water is a VERY abundant substance in the cosmos as it's formed of two abundant elements (hydrogen and oxygen) which, along with carbon and other "organic" elements, are created in the most abundant supernovae (type 1A). The promiscuous chemical properties of carbon along with the abundance of hydrogen, oxygen, etc. elements which make up the majority of organic chemistry makes them good candidates for the search of life. Assuming that chemistry out there works as it does here, a fairly safe assumption, it would appear that molecular complexity required for base level information conveyance (something like our DNA, and thus life) could form from these abundant chemicals as it did here. In other words: Our sun is not special, our organic chemistry is not special, thus we're not very special, so we should look for more places like home to find organic complexity like ours. It makes sense when you put it in these terms. There's LOTS of places like ours, some of them probably have molecules complex enough to copy themselves and thus create a positive complexity feedback loop. We don't know what other sort of life may exist, but we're more likely to find some in places like ours since we exist in such a place, and there's nothing special about our home.

      Note that in a very short period of time after an artificial information conveyance system (culture, language, writing, etc) is developed this abstract and artificial system becomes the primary carrier of ever more complex information. I would be very surprised to find life that did not begin as carbon and water based, but given the small window between intelligent life's organic beginnings and their mastery of their own biology I would be surprised to find such inefficient and fragile organic chemistry as the basis for the intelligent life forms we may encounter granted that they've mastered interstellar transportation. In space human bodies are EXPENSIVE to maintain in the absence of their planet's environment, that's why we send our more efficient and hardier machines...

      At its core life is a self descriptive system which gathers better information about propagation (read: survival) in its environment and passes it onto the future. This is what all self reinforcing systems of complexity do. Life is the universe studying and describing itself to varying degrees of accuracy and scale. This planet's DNA has been doing this sort of self modifying trial and error for billions of years before we decided to call such phenomena "science", and now science itself carries on the same process a bit more efficiently given educated guesses in addition to chance discoveries. Note that this cybernetic description of "life" does not assume any elemental constraints, and thus can be applied to abstract systems such as businesses, governments, and cultures as well as DNA and some machine systems. These are all "alive" to some extent: Where some draw the line of cellular vs multi-cellular seems arbitrary and individual vs collective organisms seem just as valid distinctions, IMO. From a cybernetic standpoint we can classify the behaviour of a "living" system in terms of information theory, and thus discover what universal properties may apply at all scales of existence (such as competition, lack of which sets systems like Communism somewhat at odds with the nature of progress itself). However, through a physicist's lens we can constrain the direction our limited resources should look for life to most likely of places: Those with water.

      You're right, there is no physical reason you MUST have water for life -- Indeed, some of my cybernetic simulations of genetic programming in selective environments I would categorize as "alive" to various degrees (networks of electrons and silicon are every bit as "real" as the electrochemical networks of your brain). However, given what we know about the chemistry which yields complexity easily and is in abundance suggests that IF any life exists beyond our planet that we SHOULD find some of this life where water is -- Even if that life is no longer propagating via "organic" chemistry.

      TL;DR: Water may not necessary, but it's a likely candidate for many reasons and may be more essential to your bodily functions than you imagine.

      • (Score: 2) by darkfeline on Sunday March 01 2015, @06:18PM

        by darkfeline (1030) on Sunday March 01 2015, @06:18PM (#151595) Homepage

        Thanks for the good comments guys, though I won't respond to all of them. You more or less described what I was thinking, though I was poor at expressing my point.

        Imagine Kerbal Space Program, except for generating life on planets. It turns out that H2O is just so damn useful/practical that everyone uses it in their life-generation project. But there's nothing stopping some passionate player from generating life without H2O, as a challenge. Of course, that means that we should focus on water when searching for life as we know it due to it being more likely...

        However, there's also the question of life not as we know it, for example, self-replicating robots and AI. In that case water is not needed at all.

        --
        Join the SDF Public Access UNIX System today!
  • (Score: 0) by Anonymous Coward on Saturday February 28 2015, @06:15PM

    by Anonymous Coward on Saturday February 28 2015, @06:15PM (#151144)

    http://en.wikipedia.org/wiki/Nanobe [wikipedia.org]

    Thinking even smaller, makes one wonder if life can also be made purely of photons?

    Non water based life may be living right next to us yet undetectable as that ethereal dark matter.

    • (Score: 1) by canopic jug on Saturday February 28 2015, @09:02PM

      by canopic jug (3949) Subscriber Badge on Saturday February 28 2015, @09:02PM (#151210) Journal

      I saw an article a long time back about having created a self-sustaining double membrane in gas plasma. That leads me to wonder if there could also be life on the sun or other stars. It would be unlikely to be complex but if the double membrane was legit, then there is potential.

      Larry Niven pondered liquid hydrogen based life in his earlier works. It could be taken the other direction outside of the temperature zone, to where only plasmas exist. We know so little about plasma, look at our abortive fusion attempts, but even if such life were theoretically possible, could it travel under any conditions and not just radiate away?

      --
      Money is not free speech. Elections should not be auctions.
      • (Score: 0) by Anonymous Coward on Saturday February 28 2015, @11:08PM

        by Anonymous Coward on Saturday February 28 2015, @11:08PM (#151271)

        abortive fusion attempts?

        Not economic, however, the Wendelstein 7-X looks to show us how to get there.
        http://en.wikipedia.org/wiki/Wendelstein_7-X [wikipedia.org]

        Just look at the coil design and tell me that isn't Star Gate looking.

        Niven is great for dreaming up life outside the box.
        Didn't he have something growing on the surface of neutron stars?

        Also, what if magnetic fields acted like the membranes instead?

        • (Score: 2) by canopic jug on Sunday March 01 2015, @06:28PM

          by canopic jug (3949) Subscriber Badge on Sunday March 01 2015, @06:28PM (#151600) Journal

          (I should have written helium, since that's what the Outsiders were based on.)

          Didn't he have something growing on the surface of neutron stars?

          One of the short stories in Neutron Star featured a planet of antimatter with some life on it.

          --
          Money is not free speech. Elections should not be auctions.