Posted on 02/04/2010 11:50:02 PM PST by LibWhacker
Cygnus bubble detail_4m Mayall NOAO (1)
Is the solar-system sized bubble in the Consellation Cygnus a planetary nebulae or could it be an "AC" or astroengineering construction, also known as a Dyson sphere, named after Freeman Dyson of the Princeton Institute for Advanced Study who proposed the theory? Dyson's thought experiment suggested that in our search for advanced extraterrrestrial civilizations that Instead of radio signals we should look for spheres, which are artificial mega structures that enclose the orbit of a star, fabricated from the material of that solar system. The key is to distinguish a Dyson sphere from natural dust components. The Dyson sphere is the marker of what Kardashev calls a Type 2 civilization, which is capable of using up all the energy produced by a star. A Type three civilization uses up all the energy produced by a galaxy."
ACs are expected to have spectra similar to the black-body spectra because they re-emit all the energy that they absorb, although in the infrared range.
"Fermi Bubbles" is the term used by Richard Carrigan at the Fermi National Accelerator Laboratory in his latest work on the search for artifacts like Dyson spheres or Kardashev civilizations. A Fermi bubble according to Carrigan would grow as the civilization creating it colonized space. Carrigan notes that, as Carl Sagan and others have observed, that the time to colonize an individual system is small compared to the travel time between stars. A civilization could engulf its galaxy on a time scale comparable to the rotation period of the Milky Way, or every 225250 million years, and perhaps, fewer.
According to Carrigan, of the 11,224 potential sources of low range emissions identified that might be a manifestation of Dyson spheres in the Milky Way there are only 16 that have strong potential.
“Is the solar-system sized bubble in the Consellation Cygnus a planetary nebulae or could it be an “AC” or astroengineering construction, also known as a Dyson sphere, named after Freeman Dyson of the Princeton Institute for Advanced Study who proposed the theory?”
No it could not, for two reasons.
First, it’s transparent (you can see stars through most of it), hence it is not absorbing the central star’s radiation and re-radiating in the infrared.
Second, Dyson spheres have been shown to be unstable over time, the central star’s gravity would cause it to collapse or at least impact the star.
Even a “ringworld” type construct would require active stabilization.
interesting comments about marerials. Funny how nobody ever thinks abotu where is all that material going to come from. can we even imagine how many planets would be totally consumed encasing an entire solar system???? Millions? trillions?
and how long would it take? centuries? millenia? Is there any affirmation that any civilization, consuming so much resources in order to construct such a thing lasting long enough to complete the task?
and for what? It would be far more cost effective for a civilization to colonize other worlds in order to spread, than pulverizing them in order to build this thing.
Uh--we can see through it. Thus it's not enclosing anything.
It's not a Dyson sphere.
Yes, such a construct would defy common sense, if a civilization could build something like that they could certainly harness energies we couldn’t even comprehend.
Harnessing a star’s output is a rather modest proposal, it would be unneccessary for them.
I don’t even see how a Dyson sphere or a ringworld construct would in any way be preferrable to multiple, large, cylindrical colonies placed at strategic points throughout various star systems..
i was just reading how they are considered unstable.
now if a society at our technological level can figure out that these things aren’t even stable, wouldn’t a society at a higher technological level be able to figure this out too?
I’m pretty sure I read something from Dyson himself that he had been mis-understood by sci-fi writers into thinking that he had meant a solid spherical structure whereas he had actually meant more of a swarm of habitats that would orbit indepentently and absorb the energy from their star.
the search for artifacts like Dyson spheres or Kardashev civilizationsI can't stand those gold-diggin' broads.
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Astronomers who still live in their parents’ basement ping.
INTERESTING. THX.
Any implications, in your view?
My sci fi roomie made the transparency argument. However, is it possible that a civilization could create a dust veil bubble as an interstellar signal which would allow stars to shine through. I would like to ask my friend, but he said, “be quiet, I am studying the market” ;-)
Also, since you seem pretty knowledgeable, what do you think it might be?
“Also, since you seem pretty knowledgeable, what do you think it might be?”
Planetary nebula blown off by a stellar event. One hopes such an event won’t happen with the Sun, it had to have been pretty violent...
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