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Astronomers Search For Dyson Spheres of Alien Civilizations

Posted by Soulskill on from the scotty-might-be-trapped dept.

Hugh Pickens writes "An article by Ross Andersen makes note of Freeman Dyson's prediction in 1960 that every civilization in the Universe eventually runs out of energy on its home planet, a major hurdle in a civilization's evolution. Dyson argued that all those who leap over it do so in precisely the same way: they build a massive collector of starlight, a shell of solar panels to surround their home star. Last month astronomers began a two-year search for Dyson Spheres, a search that will span the Milky Way, along with millions of other galaxies. The search is funded by a sizable grant from the Templeton Foundation, a philanthropic organization that funds research on the 'big questions' that face humanity, questions relating to 'human purpose and ultimate reality.' Compared with SETI, a search for Dyson Spheres assumes that the larger the civilization, the more energy it uses and the more heat it re-radiates. If Dyson Spheres exist, they promise to give off a very particular kind of heat signature, a signature that we should be able to see through our infrared telescopes. 'A Dyson Sphere would appear very bright in the mid-infrared,' says project leader Jason Wright. 'Just like your body, which is invisible in the dark, but shines brightly in mid-infrared goggles.' A civilization that built a Dyson Sphere would have to go to great lengths to avoid detection, building massive radiators that give off heat so cool it would be undetectable, a solution that would involve building a sphere that was a hundred times larger than necessary. 'If a civilization wants to hide, it's certainly possible to hide,' says Wright, 'but it requires massive amounts of deliberate engineering across an entire civilization.'"

28 of 686 comments (clear)

  1. Flawed assumptions. by Anonymous Coward · · Score: 5, Insightful

    Dyson assumed that all alien civilizations are stupid enough to believe in infinite growth, much like humanity.

    I don't believe this. I think the most advanced aliens have probably realized that there isn't much point of growth after a certain threshold.

    1. Re:Flawed assumptions. by alvinrod · · Score: 5, Insightful

      It also assumes that there aren't any energy advancements that are so far out of our understanding right now that they wouldn't seem like magic if we possessed them. Our assumptions are limited by our current understanding. In the next thousand years we could see all kinds of advancements that render building a Dyson sphere completely unnecessary.

    2. Re:Flawed assumptions. by Guido+von+Guido+II · · Score: 5, Interesting

      Dyson assumed that all alien civilizations are stupid enough to believe in infinite growth, much like humanity.

      I don't believe this. I think the most advanced aliens have probably realized that there isn't much point of growth after a certain threshold.

      But where is that threshold? Is it before or after they build a Dyson sphere?

    3. Re:Flawed assumptions. by ByOhTek · · Score: 5, Interesting

      There's the /civilization's/ recognition of the limit, vs. the individual's desire to procreate, in the battle of need vs. freedom/rights.
      I recognize that humanity has overpopulated the earth, that does not diminish my desire to have a child at some point.

      Also, as for remaining hidden, a race may decide instead of building a Dyson sphere which radiates over it's whole surface, to instead radiate over a smaller portion of the surface, and at a narrower angle. While you could be detected from the right angle, if you point it the right way, the closest thing that could bother you, probably wouldn't be close enough to care about.

      Then again, the amount of mass needed for a Dyson sphere would be insane, if you have that level of tech, to acquire that mass, you probably have other solutions to the problem (direct matter->energy conversion perhaps?)

      --
      Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
    4. Re:Flawed assumptions. by ShanghaiBill · · Score: 5, Insightful

      It also assumes that there aren't any energy advancements that are so far out of our understanding right now that they wouldn't seem like magic

      Which is a reasonable assumption. Advanced civilizations will certainly have more advanced technology, but basic laws of reality will still apply. There is no reason to believe that the second law of thermodynamics can be violated, and overwhelming evidence that it cannot.

    5. Re:Flawed assumptions. by Anonymous Coward · · Score: 5, Insightful

      I recognize that humanity has overpopulated the earth

      What do you base that on? Humanity may have overpopulated Calcutta, or Sao Paulo.
      We haven't overpopulated Wyoming.

    6. Re:Flawed assumptions. by zifn4b · · Score: 5, Interesting

      Basic laws of reality? Isn't science about increasing our understanding of reality? Many theories and ideas have come and gone and been replaced by more refined ones. We would be extremely naive to think our current understanding is even remotely close to all there is to know and completely correct. There is much to learn my friend.

      --
      We'll make great pets
    7. Re:Flawed assumptions. by Bill,+Shooter+of+Bul · · Score: 5, Interesting

      Well, the second law is more of a statistical observational law than one deduced from higher principles. Its really good at predicting things and seems really reliable and is tied into all kinds of other areas of physics. I would be shocked to near death if we found a repetable, observable violation.

      But the science fiction lover in me would prefer to think of it a just a setting in the universe that could be switched off when convineint. Its also linked to time, so if we can just step out of the stream of time then we're good and possibly gods.

      --
      Well.. maybe. Or Maybe not. But Definitely not sort of.
    8. Re:Flawed assumptions. by Anonymous Coward · · Score: 5, Interesting

      I can't recall who said it but someone (more famous than myself) put the idea out there that if you had the resources to build a Dyson sphere you wouldn't need to build one. Makes sense to me but I'm not an engineer.

    9. Re:Flawed assumptions. by Bengie · · Score: 5, Insightful

      As far as we can tell, no macro-level system can violate thermodynamics, so the postulate should hold true. There should be IR energy given off anywhere energy is consumed as IR is the end result of an system that is not 100% efficient.

    10. Re:Flawed assumptions. by deoxyribonucleose · · Score: 5, Funny

      How does science explain psychics? Auras, the afterlife, the power of prayer?

      Easily.

    11. Re:Flawed assumptions. by rhsanborn · · Score: 5, Insightful

      If I've read my recent physics correctly, 95% of the energy in our universe is in a form we don't know much about (dark matter/energy). If a sufficiently advanced civilization could harness that, they are likely going to do something to target that, instead of star light.

    12. Re:Flawed assumptions. by 0xdeadbeef · · Score: 5, Insightful

      I don't believe this. I think the most advanced aliens have probably realized that there isn't much point of growth after a certain threshold.

      It's funny how these armchair physicists who got their education from bad science fiction are so adamant that we can't possibly know what magical technology we might invent that will get us around the laws of thermodynamics, so capturing starlight is crude and stupid and this project is obviously a waste of time.

      But boy do they sure know the motivations of future humanity, the path of technological and societal growth, and the psychology of hypothetical aliens, and that knowledge also tells them that this project is a waste of time.

    13. Re:Flawed assumptions. by rufty_tufty · · Score: 5, Informative

      For those who don't get the reference it's a beat poem called Storm by Tim Minchin
      http://www.youtube.com/watch?v=HhGuXCuDb1U
      He's very much being derisive of that sort of viewpoint.
      Sorry to spoil the joke.

      --
      "The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
    14. Re:Flawed assumptions. by The+Grim+Reefer · · Score: 5, Funny

      And don't get me started on Santa Claus. How does he deliver toys to over a billion homes in one night? Science offers no plausible explanation for that.

      Relative velocity time dilation has been understood for years. Please leave your geek card at the door on the way out.

    15. Re:Flawed assumptions. by ColdWetDog · · Score: 5, Informative

      How does science explain psychics?

      It doesn't have to. Science doesn't have to deal with fairy tales.
       

      Auras

      If you mean Auroras, we've got you covered. If you mean the fuzzy, ill defined fields that come up when you overexpose film or electronic sensors, well, we've got that covered as well.
       

      the afterlife

      What afterlife? Before it needs explaining, it needs existing.
       

      the power of prayer?

      What "power of prayer"? The non existent causal relationship between other people praying for someone and having an outcomes change? That doesn't happen. The ability of the plastic human mind to influence the rest of the body (to which it's intimately connected)? May I introduce you to the concept of neurobiology in all it's complexity and splendor?

      --
      Faster! Faster! Faster would be better!
    16. Re:Flawed assumptions. by Nethemas+the+Great · · Score: 5, Insightful

      Just ignore him, he's one of those frustrating, myopic people that thinks we are limited to the resources of the ball of mud on which we presently live.

      --
      Two of my imaginary friends reproduced once ... with negative results.
    17. Re:Flawed assumptions. by tftp · · Score: 5, Interesting

      we have *always* relied on sunlight

      Past performance is not an indicator of future performance. Humans always used horses... until they invented a car. Humans were using only land transport.. until they invented an airplane. Humans were always planet-bound, until they flew into space.

      A Dyson sphere is not a scientific fact, it's only a possibility, and not trivial one at that. The approach has many problems.

      First, the Dyson Sphere, even if it is ideally constructed, will only supply energy to your sites near the star. However it is logical to expect that an advanced civilization will need spaceships for all kinds of purposes, from research to migration. This cannot be done without movable sources of energy (thermonuclear at the least.) Once you have them, the effort of building the Dyson sphere appears to be too high.

      Then the Dyson sphere needs to be constructed. There isn't much material in an average planetary system to do that, unless you can transmute your common silicon and carbon into scrith and make a thin foil out of it. You also need to deliver that material to where it is needed, and join it. A Ringworld is a much easier possibility at this point.

      Once you build the sphere you need to equip it with collectors of solar energy. Where would they come from? If we build a sphere at 1AU from the Sun, do you think we can line it with solar panels? We'd have not one atom left in this Solar system after we built the sphere. Besides, the sheer volume of the effort would be impossible.

      The sphere would need to be thermally balanced. (This is how they intend to find it.) If you collect all the energy and keep it inside it will heat up to the temperature of the star - and that is perhaps not what you want. So you need to cool it. Earth is rotating, radiating heat every night and collecting it every day. Planets like Mercury show what happens when a planet is thermally overloaded. The Dyson sphere would have to have radiators of energy somewhere on the external side, and there would have to be conduits. This is a lot of work.

      Then the question would arise of atmosphere. Is your Dyson sphere is at 1AU then you need to live on that sphere - and that means that you must have means of holding the atmosphere in place. If you leave Earth (for example) in place and instead build the sphere on a farther orbit then the surface of your sphere grows and you need even more material. Also the problem of transportation of collected energy arises.

      Considering these and other technological and conceptual difficulties, it may be easier to just use local sources of energy, like thermonuclear reactors or better. Astronomers, of course, want something to look at, and you can't look for reactors that far away. I don't think they will find Dyson spheres, though. A civilization that is advanced enough to build such a sphere probably does not need it.

    18. Re:Flawed assumptions. by sexconker · · Score: 5, Funny

      So? From the viewpoint of someone standing still, he can still not move faster then the speed of light. And any time he drops off a toy, he has to either slow down slowly, or subject the toy itself to extreme g forces. Since toys arrive in a non-squished condition (and they are generally not resistant to high g, as the kids soon discover), then Santa has to slow them down slowly - taking quite a bit of time for every toy dropped off.

      Each toy is delivered with the elf who made it.
      The elf slows the toy down on descent, places it neatly, and promptly burns itself to death in the fire place. If you don't have a fireplace the elf will flush itself, use the garbage disposal, provoke the dog into eating it, or, failing all of those, walk outside and freeze to death. Most people confuse their bodies for garden gnomes.

    19. Re:Flawed assumptions. by maxwell+demon · · Score: 5, Insightful

      The "power of prayer" goes not only against science, it even goes against true faith. If god is all-knowing and good, then he must know what is best for the people even without the people praying for it. If he needs to be told what to do, he's not all-knowing. If he does the good only if someone prays for it, he's not good. And if he does something which is not good because someone prays for it, he's even less good. Therefore we find that an all-knowing and good god cannot be influenced by prayers, and therefore the believe that prayers have objective effects (other than the normal psychological effects) shows a lack of faith.

      --
      The Tao of math: The numbers you can count are not the real numbers.
    20. Re:Flawed assumptions. by XxtraLarGe · · Score: 5, Insightful

      i can think of at least 1 scenario where 1+1=10

      Yes, but that's still 2.

      --
      Taking guns away from the 99% gives the 1% 100% of the power.
  2. Let me predict.... by slashping · · Score: 5, Insightful

    They'll find nothing.

    1. Re:Let me predict.... by Tablizer · · Score: 5, Interesting

      They'll find nothing.

      Probably, but the issue is whether it's worth looking. If there was a detectable civilization in our range, and it later was discovered that we could have detected it much earlier via a relatively small expenditure, we'd be kicking ourselves in the ass.

      Plus, it may lead to the discovery of a new unexpected natural phenomenon.

      - Sara N. Dipity.

      --
      Table-ized A.I.
  3. Re:what about nuclear fusion? by Anonymous Coward · · Score: 5, Funny

    where would you get enough matter

    Obviously harvested from the home planets of other civilizations they've destroyed. What a silly question.

  4. Re:Runs out of energy? by Errol+backfiring · · Score: 5, Informative

    Eventually, the energy is converted to heat, which can leak out into space. Our planet is not a closed system. The good thing is that there is also energy coming in into our system (solar energy, for example).

    --
    Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
  5. obviously they don't unstand TIMECUBE by Thud457 · · Score: 5, Insightful

    Against Stupidity, even the gods themselves labor in vain.


    lets see how many mods perceive the relevance to the reference

    --

    the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff

  6. Re:series of tubes by icebike · · Score: 5, Insightful

    Of course, this presumes that advanced civilizations will simply re-radiate the left-over thermal energy, it's entirely possible that they would have close to 100% efficient systems or have a economically sensible way of storing thermal energy to re-use at a later date.

    It also presumes that advanced civilizations would waste their time and resources building such a contraption, when, given the technology necessary to do so, it would be far easier to find another planet.

    The level of sophistication necessary to deploy such a thing would require a level of technology where Fusion is childs play. There would be no energy shortage.

    --
    Sig Battery depleted. Reverting to safe mode.
  7. Re:The Templeton Foundation by gandhi_2 · · Score: 5, Insightful

    The Nazis got us into space. The military industrial complex got us the internet. War gave us most of our trama medicine.

    But you take issue with this one, huh?

    --
    THL phish sticks