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Maybe There's No Life in Space Because We're Too Early 250

Long-time Slashdot reader sehlat shares "a highly accessible summary" of a new theory about why we haven't yet find life on other planets -- that "we're not latecomers, but very, very early." From Lab News: The universe is 13.8 billion years old, with Earth forming less than five billion years ago. One school of thought among scientists is that there is life billions of years older than us in space. But this recent study in the Journal of Cosmology and Astroparticle Physics argues otherwise... "We find that the chance of life grows much higher in the distant future..."

Stars larger than approximately three times the Sun's mass will perish before life has a chance to evolve... The smallest stars weigh less than a tenth as much as the sun and will glow for 10 trillion years, meaning life has lot of time to begin on those planets orbiting them in the 'habitable zone'. The probability of life increases over time so the chance of life is many times higher in the distant future than now.

The paper ultimately concludes that life "is most likely to exist near 0.1 solar-mass stars ten trillion years from now."
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Maybe There's No Life in Space Because We're Too Early

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  • by Yvan256 ( 722131 ) on Saturday August 13, 2016 @04:38PM (#52697099) Homepage Journal

    So, we're those guys [wikipedia.org] after all?

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      So, we're those guys [wikipedia.org] after all?

      Have you read/saw the news recently?, I hope we survive long enough as a species to evolve into them...I'm not optimistic though...

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        Then stop reading the news and go out for a walk.

        The news are reported by people who have an economic interest in keeping you scared.
        They are about as reliable as the traveling salesman, not every word is a lie, but most of the time emphasis is put on certain details to make you fill in the gaps incorrectly.
        One thing to keep in mind is that if something sensational happens than the news will never keep quiet to keep the reporting balanced.
        The gaps you need to fill in are the ones where good things happened

    • by Lumpy ( 12016 )

      Except we are spreading it all over the place without the altruistic goals.

      Reality is, we are just messy.

    • by somenickname ( 1270442 ) on Saturday August 13, 2016 @05:53PM (#52697349)

      I think the first few seasons of Babylon 5 is a better analogy. In fact, the first few seasons of Babylon 5 is basically about the struggle between the older races and the younger races. It's possible that we are one of the "old ones" but an early stage. It's also possible that we are one of the younger races but, to the "old ones" we are nearly indistinguishable from ants (G'Kar gives a nice speech about this).

      On a more serious note, anyone who has sat and given some thought to what the TFS talks about has probably realized that we could be one of the earliest sentient races. The universe didn't start with the ingredients of life. It was brewed in stars and then spread by the exploding of stars and the re-coalescence of that material. That shortens the possible time frame for sentient life but, you also need a fairly quiescent part of the galaxy to give sentient life enough time to form. So, really, it's impractical for sentient life to arise until *all* nearby giant stars have gone supernova. Then you have the time it takes for new solar systems to form and stabilize, basic life to come into existence, mass extinctions, the possibility that lifeforms unsuitable for sentience will dominate a planet, etc, etc.

      It really takes an extraordinary amount of luck, over an extraordinary amount of time, for sentient life to form. And, as we've seen in the last century, it also takes a lot of luck for a technological society to not destroy itself.

      • +1 Nicely done.

      • It's possible that we are one of the "old ones" but an early stage. It's also possible that we are one of the younger races but, to the "old ones" we are nearly indistinguishable from ants (G'Kar gives a nice speech about this).

        G'Kar talks to Catherine about Sigma 957.

        https://www.youtube.com/watch?... [youtube.com]

      • by dryeo ( 100693 ) on Saturday August 13, 2016 @09:46PM (#52698049)

        It really takes an extraordinary amount of luck, over an extraordinary amount of time, for sentient life to form.

        I prefer the term technological life as it our use of technology (along with our story telling) that really sets us apart. Currently on the Earth we have a few examples of life that may be sentient.
        Octopus, where their environment really puts them at a disadvantage, but the killer is no family/tribe so no passing on knowledge. Every Octopus is born alone and starts over from scratch. Humanity has been building on our ancestors knowledge since before we were human and the fact that we're story tellers sets us apart.
        Dolphins may be sentient, but no appendages for tool use as well as that wet environment. Some birds such as Ravens and Parrots may also be sentient, but once again not built for tool use and probably not much knowledge passed on.
        Who knows about previous life. The dinosaurs were around for ages and some may have been sentient but without the means of passing on knowledge. Same with lots of previous life, especially the ones that had the bad luck to be flattened by a meteorite, volcano or other natural disasters.
        And as you say, just the luck needed to have a planet that stays inhabitable for the billions of years required for evolution.

        • I would agree with you about the distinction between sentient and technological species. But, in making that distinction, you bring up another point: Energy. A species can become sentient without high energy needs. A species cannot become technological without being able to feed very high energy needs. So, the technological capabilities of a species is somewhat dictated by the natural resources of the planet the species originates from. And, oddly, by the amount of time the planet has existed.

          To give

          • by dryeo ( 100693 )

            Wouldn't we have had more Uranium and even Plutonium? A few billion years ago there were natural reactors operating as the Uranium was richer, as in enriched. The most radioactive elements/isotopes are becoming less common.
            The problem would be lack of fossil fuels, humanity did fine with wood etc up until less then 500 years ago but the industrial revolution (and even currently) was powered by fossil fuels. Whether an advanced civilization could evolve using wood and alcohol, I don't know but it seems possi

            • Agreed. And there's no guarantee fossil fuels would form at all - coal at least seems to have been an "evolutionary accident" - the result of an 80-million year window between the evolution of... I think you're right about lignin, allowing for rigid woody plants, and the evolution of the first organism capable of digesting it. Thus 80 million years worth of complex carbon sequestered under the earth as unrotting wood. (and incidentally avoiding a potential runaway greenhouse effect)

              On the other hand, ther

        • Dolphins may be sentient, but no appendages for tool use as well as that wet environment. Some birds such as Ravens and Parrots may also be sentient, but once again not built for tool use and probably not much knowledge passed on.

          Do you live under a rock?

          Dolphins use tools, so do Ravens and Parrots.

          Parrots have language, they give their offsprings names, and when parrots meet they introduce themselves with their given names. There are parrots in captivity that actually can speak and communicate on the level

          • by dryeo ( 100693 )

            Do you live under a rock?

            Just trying to not be too controversial. Lots of people who refuse to consider sentience in other animals.

      • by Roger W Moore ( 538166 ) on Saturday August 13, 2016 @11:39PM (#52698389) Journal

        On a more serious note, anyone who has sat and given some thought to what the TFS talks about has probably realized that we could be one of the earliest sentient races. The universe didn't start with the ingredients of life. It was brewed in stars and then spread by the exploding of stars and the re-coalescence of that material. That shortens the possible time frame for sentient life

        Actually if you actually read the paper [arxiv.org] (yes I know it's Slashdot so you are excused! ;-) they mention this there. All the ingredients for life, including the heavy elements, are there in the second generation stars which formed a few million years after the first generation of stars which were around ~30MYr after the Big Bang. The large stars which go supernova have very short lifetimes so heavy elements were created and dispersed into the coalescing gas clouds really quite rapidly. So instead of ~13.6 billion years for life to evolve you have ~30+a few million years less i.e. negligibly less time.

      • It really takes an extraordinary amount of luck, over an extraordinary amount of time, for sentient life to form.

        Life begun on Earth almost as soon as the surface cooled enough to get liquid water. It's been a pretty much monotonous increase in complexity since then.

        And, as we've seen in the last century, it also takes a lot of luck for a technological society to not destroy itself.

        We'll have World War III sooner or later. Probably sooner, because the generation which remembers WWII is mostly dead. The im

        • Well, not really monotonous - there were apparently a few big jumps on he way to humanity, muticellular life and nervous systems to name a few.

          As for WWIII, there's also the question of whether there will be anything left of our species to rebuild. Nuclear weapons were never nearly the threat they were portrayed as. Bioweapons though could easily be far more thorough with far less investment. Especially if designed by fanatics who might find a doomsday weapon attractive.

      • The thing is though that stars like ours, with a similar mix of elements in their planetary halos, should have been forming for a few billion years before ours did. As I recall our star formed about in the middle of the period when 3rd-generation stars like ours are believed to be likely to form. Concentrations of heavier elements around younger stars would likely have been lower on average, just as they'll likely be higher in younger stars with more supernovae in their history (though there's likely a lo

    • we might be to the extraterrestrials that find our remains like what Lucy is the the archaeologists that found her, or other primitive hominids, we would appear crude and primitive to an advanced space travelling species
    • So, we're those guys [wikipedia.org] after all?

      That is not really what this paper is saying. All they have done is calculated when intelligent life is most likely to evolve given a constant probability per unit time for intelligent life to evolve on a planet in the habitable zone of a star. This is obviously going to be weighted towards the longest time periods available because they have assumed a constant probability per unit time and, unless I missed it, do not include any possibility for intelligent life to go extinct or otherwise disappear (e.g. "

  • What I sometimes find most stunning is, how far out these planets are.
    Thousands of lightyears, sometimes even more, so we see thousands of years in the past, while our own civilisation made its biggest steps within the last 500 ~ 1000 years.

    So similar to Star Trek, we just might to get to know the club when we qualify for it (FTL Communication or Travel).....

    • by ShanghaiBill ( 739463 ) on Saturday August 13, 2016 @05:04PM (#52697195)

      Thousands of lightyears, sometimes even more, so we see thousands of years in the past

      The Universe has been around for 13.8 billion years. A few thousand years one way or the other is insignificant. TFA isn't talking about us being a millennium ahead of other civilizations, it is about us being billions of years too early.

      So similar to Star Trek, we just might get to know the club when we qualify for it (FTL Communication or Travel).....

      Even on Star Trek, there are many civilizations that decline to join "the club". Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time. Also, as we learn more and more about physics, we get more and more confirmation that FTL communication/travel is fundamentally impossible. It is highly unlikely that interstellar travel will ever be like taking the train to work.

      • by Nemyst ( 1383049 ) on Saturday August 13, 2016 @06:16PM (#52697423) Homepage

        Even on Star Trek, there are many civilizations that decline to join "the club". Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time.

        Is it though? Star Trek depicts a universe teeming with life, and in that context there will be numerous civilizations at pretty much every level of advancement possible. They show that in the series too: many episodes revolve around an incredibly advanced or primitive civilization, or even talks about distant past civilizations long since gone.

        Also, as we learn more and more about physics, we get more and more confirmation that FTL communication/travel is fundamentally impossible. It is highly unlikely that interstellar travel will ever be like taking the train to work.

        FTL travel is just the classic exception that allows sci-fi to work. Without it, just about everything in Trek would be impossible, but nowhere does Trek imply that this will happen. Instead, Trek is "assuming this is possible, what could happen?"

      • Re: (Score:2, Interesting)

        by Anonymous Coward

        Thousands of lightyears, sometimes even more, so we see thousands of years in the past

        The Universe has been around for 13.8 billion years. A few thousand years one way or the other is insignificant. TFA isn't talking about us being a millennium ahead of other civilizations, it is about us being billions of years too early.

        So similar to Star Trek, we just might get to know the club when we qualify for it (FTL Communication or Travel).....

        Even on Star Trek, there are many civilizations that decline to join "the club". Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time. Also, as we learn more and more about physics, we get more and more confirmation that FTL communication/travel is fundamentally impossible. It is highly unlikely that interstellar travel will ever be like taking the train to work.

        I have to take issue with your "FTL communication/travel is fundamentally impossible" line. It is quite possible that we are misinterpreting the data and are using it to build an incorrect conclusion. Hell, you don't even need FTL for interstellar travel if you can create worm holes or "jump gates" or any other method of moving from point A to point B in a short period of time.
        TL;DR; You cannot prove something to be impossible, only highly improbable...

      • Star Trek is silly anyway, because it is unlikely that so many civilizations would reach nearly the exact same degree of development at exactly the same time.

        I would say there may be argument for believing that conditions for life would become abundant about the sameish time everywhere and that life evolved from scratch would take about the same time it has taken on earth, before it evolves a technological evolution. But there may be many reasons why we don't hear from the others - space travel, for one thing, may never be something that becomes easy enough to do, travel time being the biggest obstacle. Or we humans may be far too optimistic about what kind of r

    • by jellomizer ( 103300 ) on Saturday August 13, 2016 @06:45PM (#52697499)

      The issue that I have with this hypothesis of the article. Is making a guess that places us many standard deviation out from the median just because there is no data. With the lack of data we should assume that we are average in every way at least within 1sd.

      • by meglon ( 1001833 )
        Sadly i already commented on this thread before reading your post. You deserve modding up. This new "theory" sounds like something on of those social sciences would come up with: really stupid conclusions off no data.
  • by Frobnicator ( 565869 ) on Saturday August 13, 2016 @04:47PM (#52697119) Journal

    The Fermi Paradox [wikipedia.org] was described over a half century ago.

    The "somebody has to be first" option is one of many options for why we don't see a Universe swarming with life.

    There are quite a few other options. Unfortunately with my faith in humanity, I'm guessing the intelligent species tend to destroy themselves options is more realistic.

    • by HuskyDog ( 143220 ) on Saturday August 13, 2016 @05:46PM (#52697325) Homepage
      I am afraid that I have never been persuaded by "civilisation will destroy itself" arguments, because (a) they have a poor definition of "destroy" and (b) options for further evolution don't seem to be well considered.

      Expanding briefly if I may: Most cataclysmic events postulated don't seem cataclysmic enough. Suppose for example there was a huge nuclear war. Might that and the ensuing nuclear winter push humanity back to the dark ages? Well, very possibly it might, but we know from practical experience that getting from the dark ages to now takes about 1500 years or so, probably rather less if you have the smoking remains of the previous civilisation to get clues from. So, we get another go at being an advanced civilisation and presumably can repeat this depressing episode over and over again (see Azimov's excellent 1941 short story Nightfall).

      For these cataclysmic events to actually make mankind extinct the population has to be reduced below a practical reproductive minimum (which clearly depends at least in part on how spread out the survivors are). We could imagine perhaps some sort of synthetic plague to which no-one is immune and which survives in the environment to such an extent that even small highly isolated populations are eventually infected. It sounds a bit unlikely to me, but again we know from experience that given a few million years our ape cousins will evolve to replace us. Of course, all primates could also be vulnerable to the disease, in which case we just have to wait even longer for an evolutionary replacement.

      Conclusion: Short of managing to destroy all multicellular life forms, planets which evolve advanced life will have advanced civilisations from then on with possible gaps.
      • Re: (Score:3, Insightful)

        by Anonymous Coward

        One problem with rebuilding a technological civilization is that it's built on the availability of energy resources. You start with wood then coal, oil, gas, then nuclear for example. They tend to build on each other and each one requires the energy production of the one before. If you need to rebuild from scratch you may have already used up the easily available resources from before. Then you would be in a position of having to develop solar, wind, nuclear using only wood/steam powered machines. That coul

      • Conclusion: Short of managing to destroy all multicellular life forms, planets which evolve advanced life will have advanced civilisations from then on with possible gaps.

        Those gaps could be measured in millions or billions of years. Once you've depleted the "low hanging fruit" energy sources, it might prove to be almost impossible to re-bootstrap an advanced civilization. You could probably even compute the percentage of a Kardashev Type 1 civilization where you've reached the point of no return. At that point, your civilization either flourishes or it has consumed too many resources to start again on a reasonable timescale.

      • but again we know from experience that given a few million years our ape cousins will evolve to replace us

        How do we know that? Bonobos and chimps are just as evolved as we are.

        • by meglon ( 1001833 )

          Bonobos and chimps are just as evolved as we are.

          Don't be ridiculous, look around... they're clearly far more advanced than we are.

      • by Kjella ( 173770 )

        Well first comes the nuclear war. Then the nuclear winter. Then the fight by the survivors for a far too small food supply. Starving men are desperate men, we'd hunt all game to extinction, empty the lakes and rivers but with crops failing there would be mass raiding and starvation. Even in the "dark ages" it was far from anarchy, before the dust settles we'd be nothing more than isolated pockets of survivors, struggling to rediscover all the basics of living off the land as ammunition, supplies and stocks

        • After a nuclear war the new civilizations have no need to dig for ore.
          The metals are lying around all over the place.

    • My favorite explanation is "it's there, we just can't see it (yet)". Even if aliens are trying to contact us directly, what are the chances that we'd pick up their signal? Assuming that more advanced tech doesn't give them some magical toys to get in touch, just more powerful lasers or radio transmitters. And if they aren't trying, would we stand a chance of picking up their domestic transmissions, or even just telltale signs of life in their atmosphere? We've barely begun finding exoplanets, barely sta
    • by guruevi ( 827432 )

      Homo Sapiens and it's immediate predecessors have had many extinction events, some apparently very near. Space is a very hostile place, I don't doubt there is lots of life all over space but intelligent life that has the need or capacity for interstellar signaling, let alone communication or travel in our general direction over the last 100 years is very, very slim.

      We can't even SEE the stars and planets beyond our own solar system very well, deciphering a foreign signal from any tiny spot on a small planet

    • Self-destruction is a possibility, sure, but it seems to be the possibility latched onto most often by those with little imagination who revel in the idea of all the sheeple getting their comeuppance. You know the types... all those doomsday/rapture/climate/etc. catastrophists who, I swear, would be happier with the destruction of the species than being wrong.

      Going with the climate example, for a second, I don't want to give the impression that I'm a denialist, or that I think climate change isn't a problem

      • by Boronx ( 228853 )

        It's also latched on to by those of us who worry about it. The blase attitude of people to the increasing power of our species is very scary. If anything, it's that attitude that will get us in trouble.

        Nuclear war probably wont wipe us out, but we might as well be dumb beasts if that's how were going to go about it. It's certainly enough to keep us from being Galactic overlords. In 100 years will we have more powerful weapons?

        Climate change won't wipe us out ... if there isn't some kind of positive feed

      • It's just a matter of keeping up with technology, and we can't. We evolve in a blind and slow process, while machines evolve fast, faster, fastest. Linear growth versus logarithmic. We lose.

        Short conclusion: The stable intelligences must be machines. They would also be long-lived to the degree that interstellar travel is no problem for them. Extremely unlikely they haven't surveyed the neighborhood and spotted all the life-bearing planets. Gets more speculative, but if they are curious, then they would quit

    • by BlueStrat ( 756137 ) on Saturday August 13, 2016 @08:00PM (#52697695)

      Unfortunately with my faith in humanity, I'm guessing the intelligent species tend to destroy themselves options is more realistic.

      My view is that intelligent species indeed do not destroy themselves, it's simply that humans have not yet been proven to be intelligent.

      If humans are still around in a few millennia, then maybe humans can be considered "intelligent".

      Strat

      • So by your definition, no species can be considered intelligent until after it has survived for a few millennia. That would make it less likely we will find intelligent life.
        • So by your definition, no species can be considered intelligent until after it has survived for a few millennia.

          More precisely, after a species has survived for at least a millennia or two after developing the capability to destroy themselves

          That would make it less likely we will find intelligent life.

          No, it just makes it more likely we will discover life that has not achieved intelligence before we discover life that has achieved intelligence. Mass destruction usually generates traces which are much more easily detected at great distances.

          Strat

          • No, it just makes it more likely we will discover life that has not achieved intelligence before we discover life that has achieved intelligence.

            But you've just statistically reduced the pool of intelligent life to find by your definition, which would statistically reduce the chances of finding intelligent life that meets your definition.

    • by meglon ( 1001833 )
      https://www.pinterest.com/pin/... [pinterest.com]

      They probably view us as a plague.
  • by 110010001000 ( 697113 ) on Saturday August 13, 2016 @04:58PM (#52697161) Homepage Journal
    There is no life in space because it is big. Really big. And time is even bigger. Species don't live forever. The chances of two species of intelligent life coexisting is vanishingly small. Even if it occurred we could never contact it, because space is too big and we are limited by the speed of light. Space nutters need to give it up: we are the only ones. Star Trek isn't going to happen, ever.
    • Re:Uh, no (Score:4, Interesting)

      by argumentsockpuppet ( 4374943 ) on Saturday August 13, 2016 @05:28PM (#52697285)

      Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space. - Douglas Adams

      But that's not the same as saying that intelligent life can't spread across a big space. There are some limits imposed by the speed of light and the speed of the expansion of the universe. That said, machines, intelligent machines with personalities of humans, couldn't spread ourselves around.

      Imagine waking up after a journey of a couple million miles and being the one who guides new life to intelligence. Maybe you do a little job here or there to make sure life develops. Maybe you perform a "miracle" or two for primitive lifeforms to keep them headed in the right direction. Maybe eventually you create a biological life-form to direct them to things that will eventually build a society capable of surviving long enough to propagate themselves into space. Sure, you'll get blamed for a lot of stuff that you don't do to keep them happy, but if your goal is expansion of intelligent life in the universe, you take the good, you take the bad you take them both and there you have the facts of life. In the universe and whatnot. Maybe humans aren't even the first.

      • That is science fiction. You obviously have been watching Prometheus. We cannot create intelligent machines with personalities of humans. We cannot attain a significant percentage of light speed needed to get to other star systems. Like Douglas Adams said: space is big. He was right.
        • by dissy ( 172727 )

          We cannot create intelligent machines with personalities of humans.

          What you claim is impossible is a thing we humans do many thousands of times every single day.

          It's called having babies. You are not a special snowflake, your body is just a machine made of billions of cells working together in a very (Very) complex system.
          The fact we do not fully understand that complex system does not change the nature of what it is.

          The question isn't if it is possible to do the thing we do multiple times a day.

          The question is only one of engineering, if we can learn the knowledge and ab

        • We cannot create intelligent machines with personalities of humans.
          Half wrong half right, the correct end of the sentence would have been "now". We can create intelligent machines, we already have plenty, e.g. IBMs Watson. With human (like) personality, not yet, but that is certainly happening during my lifetime.

          We cannot attain a significant percentage of light speed needed to get to other star systems.
          We can.
          You are misinformed.

          The simplest way is a vehicle consisting of a payload and a big chunk (well

      • naah. You create new intelligent life and what thanks do you get? They just go off, forgetting about you and giving credit to some other entity. Then they start messing with each other because they are bored, or sit around consuming stuff and getting bigger and uglier. Then they get big heads and think they can do a better job creating new life. There's just no reward in the whole thing.
      • Could space be so big that one could fit "advanced civilisations per galaxy" in a normal distribution, leaving us alone here while most other galaxies are teeming with life, ST federation style of interactions between them, wizards with midichlorians, etc.?
        For all practical purposes that would be the same as being an isolated civilisation forever.

  • by AndyKron ( 937105 ) on Saturday August 13, 2016 @05:02PM (#52697183)
    The chance of life increases over time? Really? Go figure.
    • The sum chance, not the per-time chance, yes. The same is true of all stochastic processes.

      It's like saying "the sum of flipping a coin every second and having at least 100 total tails results increases over time."

      It's because more trials are constantly being held.

      There's also a chance that life will emerge on Earth a second time.

    • I think it's more that the conditions for life become more favorable as the universe becomes more quiescent. So, over time, for many reasons, the universe is becoming less hostile to life. Thus increasing the chances for it to flourish.

    • This paper has uses so many assumptions to reach such an old and obvious answer as to render itself practically useless. I guess the bar is pretty low at the Journal of Cosmology and Astroparticle Physics. Then again Loeb is known for dressing up homework problems and publishing them as amazing revelations. Somehow the reviewers haven't caught on.

  • The Copernican principle says we are more likely to be roughly average in space and time. This would imply that something in the future limits life. For example, it could be horrible terrorist weapons like self-reproducing nanobots that eat multi-cellular life.

    • The Copernican principle says we are more likely to be roughly average in space and time.

      Evidence suggests that we are extremely exceptionally early in the development of the universe. It'll last trillions of years and we're not even at 15 billion.

  • by MetricT ( 128876 ) on Saturday August 13, 2016 @05:13PM (#52697227)

    Bacterial life appeared on this planet basically the instant asteroids stopped bombarding the planet. For all we know, life was created and destroyed several times before the Late Heavy Bombardment ceased. So it appears that simple bacterial/viral life may be commonplace throughout the cosmos. Indeed, there are tantalizing signs that Mars and Titan may harbor some form of life.

    On the other hand, complex multicellular life only appeared in the last billion years, which suggests that the leap from single-cell -> multicellular life is somewhat difficult. Our sun won't be conducive to life in another billion years, so complex life "barely" made it here.

    I would love to be wrong, but given the fact that planets appear to be commonplace throughout the cosmos, and we have yet to hear from anyone, it starts to shift the odds towards one or more of:

    1) Complex life is relatively rare and widely separated in space and time.
    2) Complex life doesn't survive long-term (nuclear war, grey goo)
    3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

    I actually lean a bit towards 3 myself, but humanity will eventually find out, one way or the other.

    • Bacterial life appeared on this planet basically the instant asteroids stopped bombarding the planet.

      How on earth can we know that? (Serious question)

    • by Dutch Gun ( 899105 ) on Saturday August 13, 2016 @05:41PM (#52697317)

      3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

      Or because no one has found a way around that pesky speed-of-light barrier, and the vast distances simply make inter-species communication, let alone travel, utterly impractical. This has always seemed, at least to me, the least romantic but most pragmatic answer to the question of why we don't meet aliens, or even hear from them.

      • 3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

        Or because no one has found a way around that pesky speed-of-light barrier, and the vast distances simply make inter-species communication, let alone travel, utterly impractical. This has always seemed, at least to me, the least romantic but most pragmatic answer to the question of why we don't meet aliens, or even hear from them.

        That doesn't explain why we don't detect their radio transmissions, though.

        OTOH, if our history is any guide, the technological period during which high-powered, brute-force radio emissions are generated is pretty short. High data rates and ubiquitous usage necessitates a cellular approach and low-power efficiently-encoded spread spectrum emissions, which would be hard to pick up at light years' distance. So maybe they're just rare enough that we haven't caught that slice of any of their histories.

      • by Chelloveck ( 14643 ) on Saturday August 13, 2016 @08:21PM (#52697779) Homepage

        Or because no one has found a way around that pesky speed-of-light barrier, and the vast distances simply make inter-species communication, let alone travel, utterly impractical. This has always seemed, at least to me, the least romantic but most pragmatic answer to the question of why we don't meet aliens, or even hear from them.

        I can't buy that, either. Intelligent machines must be possible -- after all, we're just meat machines, and unless there's some divine entity handing out souls there's nothing particularly special about us naturally-evolved organisms that couldn't be duplicated in an artificial organism. So it should be possible to purpose-build intelligent machines and send them out as interstellar probes. Make it so the intelligence can hibernate for the journey by powering down.

        Now, let's say the probe is only moving about the same speed as Voyager, 17 km/s. We know that's easily achievable. At that rate it'll take about 17,000 years to travel one light-year. So let's say our robot probe travels 100 light-years to a nearby star (1.7 million years travel time) and sets up shop. After another 300,000 years it's ready to launch two more probes. Each of them goes 100 ly and repeats. At this rate it only takes 2 billion years to span the galaxy, and we end up with something like 10^300 (2^1000) probes. Maybe we ought to build in a limiter that stops reproduction when a probe hits an already colonized system...

        Mind you, that's with some really pessimistic numbers. And it doesn't even need machine intelligence, I just think a machine has a better chance of functioning after a couple million years of travel than a hibernating meat popsicle does.

        • Yes, this argument comes up often. They call the self replicating things, Von Neumann Machines, I wonder if it is the same Von Neumann who formed our ourdays CPUs?

          Anyway: who in his sane mind would sent out self replicating probes, that need millennia if not millions of years to reach a single star/planet when he himself will die a few decades later?

          And making a voyager like probe that can replicate voyages ... that is much much more complicated than building a voyager, a launch system, a landing system and

    • 1) Complex life is relatively rare and widely separated in space and time.
      2) Complex life doesn't survive long-term (nuclear war, grey goo)
      3) Complex life does survive, but for some reason doesn't communicate or colonize other worlds (a "Prime Directive", or perhaps they "sublime" in the Ian Banks/Culture sense)

      I actually lean a bit towards 3 myself, but humanity will eventually find out, one way or the other.

      Could also be a combination of the above. It could be somewhat rare for complex, intelligent life to arise, moderately rare for it to survive, and extremely rare that it decides to make its presence known. I mean, it's possible that lots of intelligent races decide that Hawking's theory [nbcnews.com] that if there's intelligent life out there it could be dangerous is correct, and that they should therefore hide. Odds are that any other intelligent life will also have arisen in a competitive ecosystem and will have its ow

    • by BigZee ( 769371 )
      It's likely as well that civilisations rise and fall all on their own. There wasn't any natural disaster that caused the end of the Roman Empire. Yes, parts of it survived but that was not enough to prevent the dark ages. I actually think that, if we survive, we're likely to become increasingly insular and introverted, both as a species and in our communities as well. In fact I see this starting off already. The only empire actually moving forward right now is the Chinese and they're doing so by bulldozing
    • How would we "hear" from them? Our own radio broadcasts aren't really resolvable past a very short interstellar distance - not even ten light-years, if memory serves. And even if there was a civilization out there, there's no guarantee that I Love Lucy will come in with enough coherence for them to determine it's an artificial signal. And already our civilization has moved from blasting radio waves willy-nilly into space to much more efficient, lower-power, higher-fidelity communications; microwave links to

  • I say this all the time. Life clearly exists, but in our Galaxy (the only reachable life that realistically matters to us), it is likely to have existed in the past or the future. Or it simply exists too close to more massive objects, and its timeline exists far accelerated from us. In other words, time passes faster for them than it is passing for Earth. The Milky Way is by far not so big when compared to how much time has passed and time that will pass, at varying speeds.
    • "in our Galaxy (the only reachable life that realistically matters to us)"

      I disagree. Humanity has a knack for improving basic concepts.

      A hundred years ago it would take a week to fly across the US, now it takes an afternoon. There are supersonic jets that cross the Atlantic in even less time.

      Once we discover how to travel between stars in reasonable, commercial avenues, there won't be much time to the point where we cross galaxies.

      • That's clearly true, I just disagree with the viability of the idea.
      • by Tuidjy ( 321055 )

        One hundred years ago, it took actually two months to fly across the US. From September 17, 1911 to November 5, 1911, to be precise.

        As for supersonic jets that cross the Atlantic today... Are you sure? The Concord no longer flies, and its predecessor, the Ty-144 has been retired for even longer. I know of a few projects to build a private supersonic jet, but none are close to completion, and as for militaries, I do not think they fly their supersonic aircraft across the Atlantic regularly.

        All of this is

      • You fell into a trap: you assume that things are going to improve at the same rate. For millions of years humans couldn't fly at all. There is no commercial supersonic transport across the Atlantic anymore. We have a limit: the speed of light. We can't even make a spacecraft that can travel at 0.0001% the speed of light.
        • by meglon ( 1001833 )

          For millions of years humans couldn't fly at all.

          No, we've always been able to fly. It was the landing without being squashed on the valley floor we had trouble with the first few million years.

        • You fell into a trap: you assume that things are going to improve at the same rate. For millions of years humans couldn't fly at all.

          You fell into a trap. Humans have always been able to fly. It just took awhile to learn how.

          The advancement of humanity is limited by knowledge. What you are implying is a decrease in the rate of knowledge accumulation when all evidence suggests that the rate is actually growing exponentially.

          You are full of shit.

  • by Thanatiel ( 445743 ) on Saturday August 13, 2016 @05:15PM (#52697243)

    I've heard this as one of the explanations for the Fermi paradox for years.

  • Don'tcha just love that subject heading. It promises a rich and controversial argument along with Attitude that won't quit. Sorry, but it's all downhill from there.

    However our example of 'intelligent life' may be first or last, but how long *will* it last? If other life forms are as self-destructive as we are, their existence will be but a blink of the eye in the overall duration of our particular universe. Catching that fleeting glimpse will be like finding a needle in No Man's Sky.

  • Not much is known about these brown dwarf systems. They tend to have quite a bit more solar flares and solar wind in the habitual zone, wich is far closer to the star than in our own system. These may strip atmospheres away before life has a chance to exist. Further the planet forming mechanisms are not well known as current theories do not have the data to back them up with emperical evidence and in fact our theories changed significantly once these modern techniques were employed. It's an interesting
  • The smallest stars weigh less than a tenth as much as the sun

    Cool, I didn't know you could "weigh" a sun! - I thought that the best you could do is calculate its approximate mass.

    Kindda makes you wonder how big the scale must be. And what it's made of that can withstand so much heat. And what you set the scale on. (At home, I always place mine on a floor that's connected to the Earth, but I'm not sure how that could be feasible on...well...a larger "scale."

    (sorry, couldn't resist)

  • Let's imagine for a moment that somewhere a solar system just like ours formed at exactly the same moment. And I don't mean exactly at a cosmic scale (i.e. give or take a million years or three), but exactly. The solar system formed, and the planets formed and then that third planet from the sun had an impact that formed its moon (and yes, let's pretend it survived that impact just like ours did), then life started to get going, evolved...

    This takes millions, no, billions of years. And every now and then th

  • If we want to meet aliens, *somebody* has to get up off their ass (or whatever somebody has) and build the starships.
    If we are 'those people', it's going to be lonely for a long time. If not, we'll be more ready to meet whoever 'those people' are--and to participate in whatever their thing may be.
    Either way, there's no reason to sit around and wait for the Federation to show up.

  • by RubberDogBone ( 851604 ) on Sunday August 14, 2016 @05:00AM (#52698901)

    We haven't found signs or evidence because what we are looking for, or expecting to find, is just all wrong.

    To understand the problem, first think about what we know of life. It is all around us. The Earth is covered in life, in the air, in the soil, in the sea, on the land. It is everywhere. From small microbes to giant whales and even bigger creatures that have long since died out. Life comes in so many forms, it might as well be an infinite variety. It remains well beyond human ability to catalog and classify and identify.

    So we have a lesson staring us in the face: life comes in all shapes and sizes and kinds, and that's just this ONE planet. If this is typical, we can expect other planets might have similar diversity. When we look out into space, logically, we could look for this sort of world. It is, afterall, the only one we know. The only pattern.

    But that's not what happens when we look for life out there. Oh hell no. All we look for is radio signals. Look at the Earth: teeming with life, crawling with it, covered in it. Only one has ever invented radio. And then only for a bit over 100 years. None of the other billions of fine creatures has ever bothered with radio. That we know of. Just one.

    So when we look out into space, we aren't looking for life at all. We ARE looking for a copy of us, in this brief window when we had radio and made enough noise with it that it might be heard across short interstellar distances. But nobody really knows how far our signals get. And if you were on alien world doing what we do, listening for signals, but you did it 200 years ago, the Earth would be a silent and dead world. So that settles it: there is no life in space. Right?

    This is basically what is being said now: we, in our infinite wisdom, have decided to look only for exactly what we are this very moment, and having not found that so far, we have unilaterally decided the universe is empty and nobody is home.

    This is absolutely asinine. The stupidest mistake in human history: to expect to find ourselves out there, to LOOK only for that, using only primitive methods only really useful because it's all we've managed to invent, and we we do not find signs of life after just a few years looking, we declare the universe is dead.

    Netcraft now confirms: the universe is dead and you will be too, soon.

    That's pretty fucking arrogant.

    "Pathetic Earthlings. Throwing your bodies out into the void, without the slightest inkling WHO or WHAT is out here. If you had known anything about the true nature of the universe, anything at all, you would have hidden from it in terror." -Dessler of Gamilas

     

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