Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
EU Space

UEA Research Shows Oceans Vital For Possibility of Alien Life 97

Posted by samzenpus from the everything-is-wet dept.
An anonymous reader writes New research at the University of East Anglia finds that oceans are vital in the search for alien life. So far, computer simulations of habitable climates on other planets have focused on their atmospheres. But oceans play an equally vital role in moderating climates on planets and bringing stability to the climate, according to the study. From the press release: "The research team from UEA's schools of Mathematics and Environmental Sciences created a computer simulated pattern of ocean circulation on a hypothetical ocean-covered Earth-like planet. They looked at how different planetary rotation rates would impact heat transport with the presence of oceans taken into account. Prof David Stevens from UEA's school of Mathematics said: 'The number of planets being discovered outside our solar system is rapidly increasing. This research will help answer whether or not these planets could sustain alien life. We know that many planets are completely uninhabitable because they are either too close or too far from their sun. A planet's habitable zone is based on its distance from the sun and temperatures at which it is possible for the planet to have liquid water. But until now, most habitability models have neglected the impact of oceans on climate.'"
This discussion has been archived. No new comments can be posted.

UEA Research Shows Oceans Vital For Possibility of Alien Life More

UEA Research Shows Oceans Vital For Possibility of Alien Life

Comments Filter:

  • Correction (Score:5, Informative)

    by halivar ( 535827 ) <`moc.liamg' `ta' `reglefb'> on Monday July 21, 2014 @01:53PM (#47502209)

    "Vital For Possibility of Earth-like Alien Life"

    A lot of assumptions there.

    • Re: (Score:3)

      by Thruen ( 753567 )
      I wish I had mod points. Every time I hear about planets not being able to support life, this is my first thought. While it's possible that there's no radically different life forms in the universe, until we actually go out and see it, we don't really know. I'm not even sure if we should call it unlikely until we've managed to examine the planets outside out solar system more closely. Don't get me wrong, I'm not expecting it and I'll be amazed if we find anything so different from ourselves, but I don't thi

      • Re:Correction (Score:5, Insightful)

        by gstoddart ( 321705 ) on Monday July 21, 2014 @02:24PM (#47502439) Homepage

        but I don't think we should rule out the possibility

        Not only shouldn't we, we simply can't, because we have no way of knowing.

        There is no scientifically valid way to rule out life forms which are unlike our own, because we don't know what they would require or thrive on.

        The same as when people say "but why aren't we searching for life which is unlike us", the answer becomes "because we don't know how". There's no basis on which to conclude anything other than "well, we couldn't live there".

        At best, we can say a planet is uninhabitable by us, but we really cannot say it is uninhabitable by life we can't even imagine and which is significantly different from what we know.

        Anybody who tries to tell you there is no chance of life as we don't know it existing someplace is saying much more than they actually know.

        • There is no scientifically valid way to rule out life forms which are unlike our own

          I'm pretty sure there are ways to constrain the range of possibilities. One obvious thing is that no life forms will most likely be based on xenon or gold because these elements don't really form the same kind of a wide range of interesting compounds that carbon does. The laws of physics (and chemistry) are the same pretty much everywhere, and just because our brains (and computers) are incapable of reaching more significant conclusions on this issue at this very moment doesn't mean that it's going to stay

          • Re: (Score:2)

            by Evtim ( 1022085 )

            I always viewed it this way: IF there is a significant number of intelligent life forms out there, then more likely than not we are "common", i.e. likely to be "in the middle of the distribution". Therefore I am a [skeptical] carbon jingoist. Also, it seems that intelligence requires certain level of complexity of the physical carrier and not many chemical elements can give rise to vast numbers of complex compounds - the mighty carbon beats them all. Due to historical reasons in my language we call the carb

          • The laws of physics (and chemistry) are the same pretty much everywhere

            Where, precisely, do we know that the laws of physics are different from those we see here? "pretty much everywhere" implies that there is somewhere that isn't included. Where is that?

            • For example, in the immediate vicinity of a magnetar, the strong magnetic fields would deform electron orbitals to the extent that life chemistry with complex molecules simply might not work.
              • Those strong magnetic fields would, indeed, change the energies of electron orbitals (indeed, of proton orbitals inside complex nuclei too), but they'd do so in accord with the laws of physics. That would (probably ; IANA quantum mechanical chemist) change the laws of chemistry to be different to those that apply in lower magnetic fields (and lower field gradients too). However the underlying laws of physics will still be the same.

                There's a very definite hierarchy of precision and strength of lawfulness in

        • Re:Correction (Score:4, Interesting)

          by khallow ( 566160 ) on Monday July 21, 2014 @06:03PM (#47503967)

          There is no scientifically valid way to rule out life forms which are unlike our own

          1) Life will require energy flow. More fully, life will operate much like a heat pump tapping energy flow between a high entropy or temperature sink to a lower entropy or temperature sink.

          2) Life will require an environment it can survive in. This story attempts to address part of that with the idea of climate buffering.

          3) As K. S. Kyosuke noted in his reply, life will require some matrix capable of the complex morphological structures and behaviors that life will need to survive.

          4) Life will need time or a shortcut (like a creator) in order to develop. Evolution-based life will need time (measured in generations) for adaptation to occur.

          For example, let's take an isolated "rogue planet". First, it's an object massive enough to round itself under the force of its own gravity, but not massive enough to undergo fusion. Second, it's not orbiting a star and basically is slowly cooling down to the temperature of the cosmic microwave background (no external energy inputs of note). The driver for any life would have to be heat flow from the interior due to heat of formation and possible radioactive decay. The situation is contrived (but in a way that actually probably appears billions of times in nature, just in our galaxy) so that there is no other means to provide significant energy flow to the system.

          Restriction 2) is rather simply solved since the environment is very stable over billions of years (unless the rogue planet happens to get too close to a star or runs into something).

          Restriction 3) requires either complex chemistry (from elements other than hydrogen or helium) or structure from say possibly, the interaction of different phases of metallic hydrogen and electromagnetism at the core of a gas giant.

          Restriction 4) means that if it's evolution-based life derived from abiogenesis, then it needs to be in a high enough energy flow over large enough volume so that enough generations can pass to evolve to a state where they can technically qualify as life (such as traits/information passed from past organisms to future ones). We don't know how big that would need to be, but bigger and older is better. Similarly, we would need the presence of complex structures, which are more likely in a high energy flow environment (eg, amino acids created by weather-induced lightning).

          If it's creator-derived or evolved elsewhere and migrated, who knows. The resulting organism might be able to fuse deterium and/or helium 3 isotopes, for example. That allows for creation of higher weight elements too.

        • The same as when people say "but why aren't we searching for life which is unlike us", the answer becomes "because we don't know how". There's no basis on which to conclude anything other than "well, we couldn't live there".

          The answer is we are. It's called SETI. Whether it's a useful means of carrying out that search is another question.

      • Although, the more similar the lifeform is to us, the more likely it is to actually matter to us. If it is sub-intelligent, then it might meet some definition of "life," but would have no impact on life here. The other direction is more interesting though - what if it's way beyond us? In that case we must ask why it either did not find us first, or chooses not to interact with us.

        • Re:Correction (Score:4, Insightful)

          by gstoddart ( 321705 ) on Monday July 21, 2014 @02:38PM (#47502537) Homepage

          If it is sub-intelligent, then it might meet some definition of "life," but would have no impact on life here.

          Oh yeah, what if they're tasty? Some Cerulian maple-bacon pig or something. ;-)

          But, more importantly, if we find life on another planet (or wherever), of any form, intelligent or not, that in and of itself would have a huge impact on life here even if we couldn't get there.

          Because the answer to "is there life anywhere else" will have been answered, and the people who loudly say there is only life on this planet will be proven wrong.

          And, if we know there's like here, and then confirm there's life elsewhere ... given the size of the universe, you would more or less have to conclude that life is pretty widespread.

          Even if it was unintelligent, the discovery of life elsewhere in the universe would be utterly monumental in a lot of different ways.

          To me, I don't think you can overstate just how big of a deal that would be. Because it would be a complete game changer in a lot of ways, and lay rest to the notion that Earth is singularly unique in that regard.

          I just don't see such a discovery having 'no impact'. Not even a little.

          • Well, what specifically would be changed by the discovery of non-intelligent life? Some astrobiologist says, "based on spectrum analysis we think their is an exchange of gasses on planet X indicative of biological processes." Over the next 15 or 20 years there is more data collection and analysis and gradually more people become convinced. But it is still a hundred light years away.

            Admittedly I am more of a critic of how people will react than a predictor of it. Many people still see landing on the

            • Well, for starters if we discovered a convincing atmospheric evidence of life then I would bet that launching a gravitational-lens telescope for a closer look would become a major priority. Even it if could only resolve planetary surface features to a few meters the spectroscopic data alone would provide enormous amount of information, including a *lot* of information on the specific local biochemistry. A great deal of the science we're only beginning to do on our own planet thanks to orbital monitoring

            • How so? What did it accomplish or change?

              There's more than a touch of irony in military project that reached the ultimate high ground only to show us that the world domination game was not worth playing.

              But I guess you had to be there to really grasp the significance of Apollo's role in the cold war. Personally I think the 1968 "earthrise" photo from apollo 8 was the most significant contribution, it's often credited with igniting the environmental movement (along with the book "Silent Spring").

              The notion of the "pale blue dot" (google it) c

              • With all the subsequent advances in unmanned space exploration, it is stunning to be reminded that these images first came from a manned mission. It has been decades since robots couldn't be sent to places that people cannot go. Mars feels like old hat.

          • And, if we know there's like here, and then confirm there's life elsewhere ... given the size of the universe, you would more or less have to conclude that life is pretty widespread.

            Would you? You really wouldn't until you found life far away, unless you found a way to conclusively rule out panspermia.

      • Re:Correction (Score:5, Insightful)

        by the gnat ( 153162 ) on Monday July 21, 2014 @02:51PM (#47502633)

        I wish I had mod points. Every time I hear about planets not being able to support life, this is my first thought.

        And every time a story about extraterrestrial life gets posted on Slashdot, several dozen people say exactly the same thing, as if they've had some brilliantly original insight that the scientists researching the subject missed. No one is explicitly ruling out the possibility that there are gaseous lifeforms living in the clouds of gas giants, or silicon-based rock monsters like the one in Star Trek. Hell, it would be a huge discovery if we found something like that. But since we're presently incapable of observing such lifeforms firsthand, and have no idea what we should be looking for at a distance of light-years, we have to settle for looking for the planetary "signatures" of temperature, oceans, oxygen content, etc. It may not satisfy the pedants, but it's still extremely difficult by itself. When we're capable of actually exploring other solar systems directly, then maybe we can start to look for fantasy lifeforms on frozen airless rocks and methane clouds.

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          No one is explicitly ruling out the possibility that there are gaseous lifeforms living in the clouds of gas giants, or silicon-based rock monsters like the one in Star Trek.

          Actually, we know almost all basic chemistry, and the range of (stable) molecules that silicon can form is orders of magnitude less than for carbon.
          There is a lot of silicon to be found on/in the surface of our planet (over 900 times more than carbon), and yet lifeforms here didn't integrate it in their core chemistry. At most they used it to reinforce surface/skeletal structures.
          It also doesn't readily form gaseous molecules like carbon does (CO2), which would help in energy cycles.

          • Re:Correction (Score:4, Insightful)

            by the gnat ( 153162 ) on Monday July 21, 2014 @05:33PM (#47503769)

            Actually, we know almost all basic chemistry, and the range of (stable) molecules that silicon can form is orders of magnitude less than for carbon.

            Well, yeah, but I didn't want to offend the pedants even further. Unless the laws of physics (and therefore basic chemistry) are very different elsewhere in the galaxy, it's not unreasonable to think that carbon-based, liquid-water-dependent lifeforms are the most probable. In fact, I'd be willing to bet a tidy sum of money that the overwhelming majority of unique forms of life are not terribly dissimilar from ours as far as the underlying chemistry is concerned. They might be fantastically alien in all sorts of other strange ways, but they'll still be based on simple organic polymers. But this is still irrelevant to the discussion at hand, because even if there were different forms of life, we have no idea how we might detect them at astronomical distances.

    • Extremophile [wikipedia.org]

      I'm thinking more along the lines of "Life that will use radio signals (or similar) to communicate in such a way that we have a chance of detecting them without either of us leaving our solar systems".

      But that's a bit wordy.

      • There's a couple things here:

        1. Extremophiles evolved progressively to more difficult ecosystems. They came from organisms that could manage in chemically unreactive of mostly water/salt water. It's unlikely the precursors to life, like prions or unbound mRNA chains would've "made it" in arsenic lakes or boiling lakes. But some prokaryotes could manage in environments with a little arsenic, and evolution could work its magic.

        Like the creationists say, getting something as complex and robust as a modern

        • Re: (Score:2)

          by itzly ( 3699663 )

          2. The utility of radio waves for communication wouldn't hinge much on the physic form of an organism, just something much like sapience.

          Radio waves don't reach very far before they are drowned out by natural sources of radiation. Beyond one light year, you already need powerful radio sources, combined with large antennas to detect them. And there's only a short time window. It took earth billions of years before we started emitting radio waves, and already we're reaching the end of the window with the increased use of wide spectrum digital transmissions that are much harder to detect from a distance.

          • Re: (Score:2)

            by smaddox ( 928261 )

            Also, efficient data transmission is indistinguishable from noise if you don't know the protocol.

            It's worth noting, however, that the SETI program only ever really looked for explicit beacons from alien civilizations, hence why they picked the radio frequency of positronium spin flip (and other similar frequencies from fundamental physics).

    • Even on Earth [nsf.gov] there are a lot of creatures [wikipedia.org] that can survive conditions [wikipedia.org] far outside the normal range.

    • "Vital For Possibility of Earth-like Alien Life"

      A lot of assumptions there.

      We can't even communicate with other species here on Earth in the same Class as us. Elephants, whales, and dolphins show signs of intelligence. Certainly enough to communicate with each other. And we've hunted species of two of them to the verge of extinction. The Great Apes are in the same Family as humans and we can't have a meaningful conversation with them. Perhaps they are simply too primitive. Or maybe we aren't as smart as we would like to believe.

      A non-terrestrial species may communicate using some

      • Re: (Score:1)

        by Anonymous Coward

        The Great Apes are in the same Family as humans and we can't have a meaningful conversation with them.

        Depends on how you define that. We know a bit of the vocalized language of some apes, but one problem here is that within one species there is no single, unified language.
        It's the same with humans: I can't have a meaningful conversation with a Chinese person in Cantonese (and have little doubt I ever will). Even two random Chinese likely don't understand each other, since there are so many dialects.
        But despite this, we have successfully communicated with apes that were reared from infancy. They seem to unde

  • Swampland! (Score:4, Funny)

    by TechyImmigrant ( 175943 ) on Monday July 21, 2014 @01:58PM (#47502265) Homepage Journal

    This makes sense. The University of East Anglia exists in swampland that is slowly sinking while the sea is slowly rising. It's halfway to ocean already.

  • Why?

    No flint tools or fire. Ergo, when we get there we can eat them!

  • That proves it is wrong... Actually Mars probably had a northern ocean but we do not know if ever supported life. I suspect that Earth is in a delicate balancing act. Not too much and not too little water. BTW, if you averaged all the elevations on earth, none of it would be above the level of the ocean. If plate tectonics stops, as it probably will in a billion or so years, then all the continents will be eroded to nothing and Earth will be a water world.

    • > BTW, if you averaged all the elevations on earth, none of it would be above the level of the ocean.

      This would be true of any planet with any amount of surface water.
      Given a perfect sphere, the water is just going to spread out and cover it.

      You can't go around leveling the land without impacting the water level. They are linked.

      • This would be true of any planet with any amount of surface water.

        This statement isn't true. The rest of your statements are true.

        Consider a perfectly spherical planet with no surface water, but with an underground water supply not too far below the surface (eg. as Europa is hypothesized to be).

        Now make it less smooth, eg. slam it with meteors such that there's no net loss in matter (possibly a slight net gain), but it's no longer perfectly smooth.

        Now you have surface water on a planet with an average elevation higher than the water level.

        Basically, any planet with surfa

      • ACK, you are right. What I meant to say is that the total volume of land above water is a lot less than the total volume of seawater. Earth is a water world. If it was not for plate tectonics then there would be no land masses except possibly some hotspot volcanos (i.e. like Mars) poking up to the surface, but no continents.

        • Yup.

          From what I've read, it seems that plate tectonics have something to do with bringing water to the surface, so it might be a more co-dependent relationship between P.T., oceans and continents.

    • Actually if I remember my Dune correctly water was once plentiful on Arrakis, but was locked away deep underground by the larval sand trout in order to provide a more hospitable environment for their adult form, the sand worms.

      Also, if plate tectonics stops that means our planet's core has cooled to the point where it can no longer provide a strong magnetosphere, at which point the solar wind will begin stripping away our atmosphere, boiling away the oceans in the process as the air pressure drops, and leav

      • Re: (Score:2)

        by dryeo ( 100693 )

        Venus is a counter argument to the idea that without plate tectonics and/or a strong magnetosphere the atmosphere would be stripped away. At that some theorize it is the plate tectonics (and life) that remove carbon allowing our atmosphere to be as thin as it is.

        • Fair point. In fact while confirming it I came across the fact that Earth is actually losing atmosphere to space faster than Venus - something that appears to rather harshly conflict with our theories on the subject.

          • Re: (Score:2)

            by dryeo ( 100693 )

            It's complex. Note that Venus has lost most of its hydrogen and like the Earth, its helium. For the Earth, much of the atmosphere losses is probably hydrogen liberated by photo-disassociation of water which is where much of our hydrogen is tied up. Heavier molecules such as CO2 get held by gravity.
            One future scenario for the Earth is to become Venus like, perhaps as soon as a billion years. The Sun gets hotter over its lifetime due to increasing percentage of helium from fusion increasing density, eventuall

  • Not to put too fine a point on it, right? Look, you need to base a model on something before you can even guess it might possibly mean something. World of Warcraft is a lovely model, but it doesn't predict the nature of life on other planets, it's just a game. This is not remotely news. Get back to us when it's been demonstrated to reliably predict the presence of life.
  • the last dolphin says "so long and thanks for all the fish"
  • To me, UEA = Universala Esperanto-Asocia, the organization tasked with assisting speakers of the language Esperanto.

    I thought maybe they'd branched out in a totally unexpected way.
  • This result (which basically says that any planet with life has to look like ours) reminds me of an article I read long, long ago speculating on what ETs would look like. The author basically concluded that they'd have to look exactly like us, i.e. two arms, two legs, head on top with two eyes and a mouth and a nose, etc., and he had arguments for why each of these things was necessary. Of course, almost none of the thousands of other species on Earth look exactly like us, but that didn't faze him in the

    • Re: (Score:2)

      by smaddox ( 928261 )

      Because complex chemistry is a prerequisite for life. There's a reason organic chemistry (carbon-based chemistry) is it's own topic--it's extremely complex.

    • Of course, almost none of the thousands of other species on Earth look exactly like us,

      Exactly? Come back here with those goalposts. Creatures here have eyes above nostrils above mouth for a reason; likewise, they have head above body (at least in some positions) for a reason. The mouth is at one end, the ass at the other. If it were advantageous to have these features somewhere else, they might well. For anything which meets our definition of life, it's reasonable to imagine that they would take on a similar form.

  • Neil DeGrasse Tyson (Score:4, Interesting)

    by The Evil Atheist ( 2484676 ) on Monday July 21, 2014 @11:11PM (#47505155)
    As Neil Degrasse Tyson notes, the life we do know is primarily made of, in order of proportions - hydrogen, oxygen, carbon, nitrogen, other. Other than helium, the order matches exactly the proportions of "normal" matter in the universe. It's not a stretch to look for life made up of the most common elements in the universe.

Slashdot Top Deals

I have hardly ever known a mathematician who was capable of reasoning. -- Plato

Close