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Astronomers Search For Dyson Spheres of Alien Civilizations

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.'"

10 of 686 comments (clear)

  1. 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!
  2. Re:Planet-based solar? by Anonymous Coward · · Score: 3, Informative

    Further, in the traditionally-envisioned model of the Dyson Sphere (hollow sphere around a star; not Dyson's actual theory), the livable surface area of the sphere would come out to something on the order of millions of Earth-sized planets. Population control at that scale, for a society with that kind of capability, is essentially a non-issue for any reasonable length of time.

  3. Re:energy leakeage by Hentes · · Score: 4, Informative

    Energy can't be used for work, only energy difference can. If they didn't radiate away the captured sunlight they would overheat very quickly.

  4. Re:Efficiency by confused+one · · Score: 3, Informative

    If the civilization has achieved 100% energy efficiency, there would be no radiated heat, as that is simply wasteful.

    Fundamental laws of physics apply, even if you're a technologically advanced civilization.

  5. 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" -
  6. Re:what about nuclear fusion? by ShanghaiBill · · Score: 4, Informative

    There really is no way to build a 0.35mm steel plate in space for more than 500 miles without it collapsing into a rubble pile.

    Dyson was well aware of that. A Dyson Sphere is not a connected solid sphere. It can consist of billions or trillions of independently orbiting structures, such as O'Neill Cylinders.

    A solid structure would be a Ringworld, which is impossible to construct with our current understanding of reality.

  7. 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!
  8. Re:Flawed assumptions. by EverlastingPhelps · · Score: 4, Informative

    These are known as Dyson Swarms and Dyson Bubbles, and would have similar characteristics.

  9. Re:Flawed assumptions. by Genda · · Score: 2, Informative

    I know Santa's big, but he ain't big enough to bend space time!!!

  10. Re:Presuppositions by b4dc0d3r · · Score: 3, Informative

    You did not read the post before asking gottabeme to read yours. The post began with an illustration of assumptions being made, then listed your assumptions.

    If I pray for something and it does not happen, that does not mean my prayers were not answered. Or if I think about something without praying and my non-prayer does not appear to be answered, that does not mean it wasn't. My prayer, combined with that of others, may result in a situation in which it is not obvious to me that my prayer, or non-prayer, was even considered.

    A kid finds a lamp, rubs it to shine it up a bit, and out pops the Genie.
    The genie grants him one wish.
    The kid says "I want to be Batman." So the Genie kills the kid's parents.

    Was his request granted, and does the kid see that his request was granted?

    We don't have the first clue what an alien civilization might do. We may have found one which is desperately trying to communicate with us but we just don't know it. We have a thought experiment by Dyson which is attempting to solve the problem by extrapolating from a string of assumptions which statistically speaking are probably increasingly invalid. The same flaw you made in your post. We may never find aliens, because they may not want to be found, and we almost certainly will never find God because he requires faith, not proof.