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Astronomers Search For Dyson Spheres of Alien Civilizations

Soulskill posted about 2 years ago | from the scotty-might-be-trapped dept.

Space 686

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.'"

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series of tubes (2)

xavieramont (1356337) | about 2 years ago | (#41559013)

Don't they mean Matrioshka brain?

TFA is educated stupid (4, Funny)

Thud457 (234763) | about 2 years ago | (#41559281)

Dyson doesn't have spheres, Dyson has balls [google.com] !

But nothing sucks like an Elecrolux.

Flawed assumptions. (5, Insightful)

Anonymous Coward | about 2 years ago | (#41559051)

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.

Re:Flawed assumptions. (5, Insightful)

alvinrod (889928) | about 2 years ago | (#41559131)

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.

Re:Flawed assumptions. (5, Insightful)

ShanghaiBill (739463) | about 2 years ago | (#41559245)

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.

Re:Flawed assumptions. (5, Interesting)

zifn4b (1040588) | about 2 years ago | (#41559345)

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.

Re:Flawed assumptions. (0)

Anonymous Coward | about 2 years ago | (#41559435)

A century ago we were not using Nuclear power. In another Century we may be using Quantum power, or harnessing Dark Energy (expansion of the Universe) itself.

Re:Flawed assumptions. (5, Interesting)

Bill, Shooter of Bul (629286) | about 2 years ago | (#41559473)

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.

Re:Flawed assumptions. (5, Interesting)

Guido von Guido II (2712421) | about 2 years ago | (#41559141)

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?

Re:Flawed assumptions. (5, Interesting)

ByOhTek (1181381) | about 2 years ago | (#41559155)

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?)

Re:Flawed assumptions. (5, Insightful)

Anonymous Coward | about 2 years ago | (#41559299)

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.

Re:Flawed assumptions. (0)

Anonymous Coward | about 2 years ago | (#41559377)

so lets!! so that when calcutta burns from riots so does wyoming?
wtf man

Re:Flawed assumptions. (2)

dragon-file (2241656) | about 2 years ago | (#41559469)

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.

And there's still the ocean... we could go all Kevin Costner.

Re:Flawed assumptions. (1)

hierofalcon (1233282) | about 2 years ago | (#41559493)

Actually Wyoming would be challenged by water resources to support a very large population since most water is required to be released to the downstream users of the various rivers - whether agricultural or human in any direction you'd care to look and the population centers in the far south - Phoenix or various California cities want more all the time. Part of it is classified as desert and most of the rest is pretty arid in general. As the winters become less severe, the available water will be drastically reduced as the state relies on a lot of snow melt for the water it does store for its own use.

So although you're welcome to try to overpopulate WY, it wouldn't be easy to do.

Re:Flawed assumptions. (1)

danlip (737336) | about 2 years ago | (#41559305)

I recognize that humanity has overpopulated the earth, that does not diminish my desire to have a child at some point.

It may not diminish your desire, but hopefully it alters your actions. At the very least I would hope you would choose have 1 or 2 and not 3 or more. If all couples had just 1 child the population would drop by 50% each generation (obviously with a time delay since people live much longer than one generation). 2 is steady state.

Re:Flawed assumptions. (1)

Daniel_Staal (609844) | about 2 years ago | (#41559355)

Dyson's original proposal wasn't they built it all at once, or even that it was solid piece: Building ever more solar energy collectors and putting them into different orbits will eventually do the same job, and put out the same signature radiation.

Basically, the assumption is that the one true limiter on growth/productivity is energy (a reasonable assumption looking at human history) and that eventually a growing race will capture all the energy they have available to them.

Re:Flawed assumptions. (4, Insightful)

ShanghaiBill (739463) | about 2 years ago | (#41559333)

Dyson assumed that all alien civilizations are stupid enough to believe in infinite growth,

No, he didn't assume that all civilizations would take this path, just some of them. The Universe should contain billions of civilizations. If even a tiny fraction of them build Dyson Spheres, then this search may find something.

Alien civilizations are likely products of the same kind of Darwinian process that produced humans, so the desire to expand and grow will be innate, because species which lack that desire are replaced by those that possess it.

You ain't seen me, right? (0)

Anonymous Coward | about 2 years ago | (#41559055)

A thought occurs to me that a civilisation capable of building a dyson sphere would only try to hide if there is something to hide from. Maybe there is a von-neumann machine swarm out there eating everything, and everyone is hiding rather than be transformed in to more of the swarm?

Re:You ain't seen me, right? (0)

Anonymous Coward | about 2 years ago | (#41559197)

a civilisation capable of building a dyson sphere would only try to hide if there is something to hide from
Other civilisations that would see them as a food source or as a resource?
look at how earthlings treat life on this planet today,
now extrapolate it by a billion years and who knows, they might be out there and are just as scared as a mouse is of a Lion

Re:You ain't seen me, right? (1)

ByOhTek (1181381) | about 2 years ago | (#41559199)

Yeah, but remaining in a shroud of folded space-time that you couldn't enter, without the allowance of those inside, or be destroyed at the subatomic level, would be a much better solution, I think.

Re:You ain't seen me, right? (1)

Half-pint HAL (718102) | about 2 years ago | (#41559287)

I'm also confused as to how you can judge the likely frequency of light when you don't know what their building the friggin' thing out of. I mean, if they're advanced enough to collect and build the materials to make an inconceivably large solar array in space, maybe they'll be able to work out an even more efficient means of gathering light and reabsorbing any waste heat -- ie no leakage. (Heck, even a Sterling engine would be pretty efficient when there's a massive solar collector on one side and cold, black vacuum on the other.)

Re:You ain't seen me, right? (2)

h4rr4r (612664) | about 2 years ago | (#41559397)

The cold black vacuum is not going to take a lot of heat. There are few particles for that heat to go to.

While space itself is cold, it makes a very good insulator. So you might want to rethink that sterling engine.

what about nuclear fusion? (2)

alen (225700) | about 2 years ago | (#41559057)

i'm sure an advanced civilization will master Star Trek type fusion tech before doing something ridiculous like building a starlight collector.

the earth compared to the sun is like a grain of sand to a beachball. where would you get enough matter to build something around a star if the same or similar size ratio will exist in other star systems?

Re:what about nuclear fusion? (5, Funny)

Anonymous Coward | about 2 years ago | (#41559085)

where would you get enough matter

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

Re:what about nuclear fusion? (0)

Anonymous Coward | about 2 years ago | (#41559135)

Even if you could find enough matter, where are you going to get the energy needed to move it all into place

Re:what about nuclear fusion? (1)

nschubach (922175) | about 2 years ago | (#41559147)

I'm also sure that if a civilization was so advanced they could make a dyson sphere that they' be able to "hide" from a civilization barely scraping space from a planet they haven't fully explored.

Though, the "tailpipe" conjectures being made are fun to read about... it just screams of movie plots.

Earth alone has a perpetual energy supply. (1, Interesting)

goombah99 (560566) | about 2 years ago | (#41559157)

moreover, the earth is a collector of solar and lunar energy. We call it wind and sunshine and tides, there's even solar "wind" if one goes a bit outside the atmosphere. Together these have more than enough energy to power all of the earths needs. Harvesting these may not be simple, but it would be a lot simpler than a dyson sphere. ergo, no dyson spheres will ever be built unless the planet is too far from the sun to collect enough solar energy on its crossection.

What the earth lacks is a perpertual supply of transportation fuels or a means to adequately replace them. But replacing them is forseable and we don't absolutely need them--we just over exploit them now because we can.

Re:what about nuclear fusion? (4, Insightful)

Shrike82 (1471633) | about 2 years ago | (#41559159)

The energy output of a star is going to be many orders of magnitude higher than what you'd get from fusion technology. The sun is a giant fusion plant itself! A sufficiently advanced technological civilisation may very well find itself bound only by the amount of energy it could produce or harness, and getting every last scrap of energy from a star is a massive boost to an energy based economy.

Re:what about nuclear fusion? (0)

Anonymous Coward | about 2 years ago | (#41559173)

Where would the matter come from? You just take a coupla otherwise-useless gas giants apart.

Re:what about nuclear fusion? (3, Interesting)

Nemyst (1383049) | about 2 years ago | (#41559253)

A star is a fusion reactor. In fact, if you need the kind of power that's given out by a Dyson sphere, then a Dyson sphere is by and large the most efficient method for generating it, especially for long periods of time.

The question should be whether any civilization would require so much power in such a static and concentrated way (as opposed to dispersed across hundreds of planets across thousands of lightyears), and where they'd find the materials required to build it (we're speaking about transforming entire planets from crust to core, or harvesting dozens more in a less destructive fashion).

Re:what about nuclear fusion? (1)

confused one (671304) | about 2 years ago | (#41559437)

OK, there are two issues here to discuss...

You could certainly build fusion power plants. Lots of them. As your power requirements go up as a society, you just build more. Except... The waste heat. No power generation process is 100% efficient. In fact, 30% may be a reasonable number for a nuclear plant. The remaining 70% becomes waste heat dumped into the environment. Now, what happens to the electrical energy you made -- the 30%? Some of that will get turned into "stuff" or into forms of potential energy. A substantial fraction will likely get converted into heat. So, as you build more and more power plants, you put more and more heat into the environment. You can already see this in localized heating of rivers where power plants draw water for cooling. If society becomes orders of magnitude more energy intensive than we are now, the heating of the environment could become a significant problem; and, the same would apply to any hypothetical advanced alien society.

As to where you get the material to build a Dyson sphere... To begin with that's a misnomer. No one would build a sphere -- they'd build a ring or a large number of orbiting platforms. As you pointed out, the solar system is vast. If your society is becoming advanced enough, large enough and energy intensive enough that you might consider a Dyson sphere, then you're probably going to have (or be able to develop) the ability to mine the non-habitable planets, asteroids, etc. for the raw materials you need.

Let me predict.... (5, Insightful)

slashping (2674483) | about 2 years ago | (#41559071)

They'll find nothing.

Re:Let me predict.... (0)

Anonymous Coward | about 2 years ago | (#41559217)

Plus a billion Insightful!

Re:Let me predict.... (5, Interesting)

Tablizer (95088) | about 2 years ago | (#41559363)

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.

Re:Let me predict.... (0)

Anonymous Coward | about 2 years ago | (#41559475)

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

This.

I think the real payoff from the search will be when they find stuff they weren't even looking for.

More eyes on the sky isn't a bad thing.

Re:Let me predict.... (1)

Half-pint HAL (718102) | about 2 years ago | (#41559491)

They'll find nothing.

Probably, but the issue is whether it's worth looking.

...and the answer is "probably not". A single purpose two-year search is stupid. The proper answer is to shove the signature into the list of things that computers automatically search for when analysing the skies and let the computer search from now until Type II civilisation kingdom come.

Re:Let me predict.... (3, Insightful)

interval1066 (668936) | about 2 years ago | (#41559499)

Perhaps. You seem to be making an assumption that many naysayers make, that is we've made a huge effort in detecting exo-planetary intelligence and come up with nothing. Let me add that our efforts so far have been miniscule when campared to the real relative distances involved in the search. Meaning that a real search effort with the given technology may be a bit beyond our current economic and technical ability.

Re:Let me predict.... (1)

zlives (2009072) | about 2 years ago | (#41559419)

o they will find it... just before they find a giant cube closing in on it :)

Re:Let me predict.... (0)

Anonymous Coward | about 2 years ago | (#41559467)

Or maybe they will. You don't know, that's the point - none of us do until they try it. If they do find nothing we will have learned something about the universe even if you don't recognize that.

Oh please... (1)

Anonymous Coward | about 2 years ago | (#41559073)

> Astrologers Search For Dyson Spheres of Alien Civilizations

Planet-based solar? (1)

GameboyRMH (1153867) | about 2 years ago | (#41559079)

Wouldn't planet-based solar be far more affordable and efficient, and produce more than enough energy for a planet with population controlled at a reasonable level, which should be expected from any advanced civilization? Seems like it would be unlikely for an advanced civilization to build one of these given the other options (including fusion power)...

Re:Planet-based solar? (2)

ByOhTek (1181381) | about 2 years ago | (#41559215)

Actually, depending on the level of respect for freedom, population control may not be expected.

The desire of the individual and of the civilization are often in conflict, and procreation tends to be one of the areas of conflict.

Re:Planet-based solar? (1)

GameboyRMH (1153867) | about 2 years ago | (#41559297)

With too much respect for freedom (aka FYGM attitude) and an insufficient sense of egalitarianism they just wouldn't reach that level of advancement. The individuals would need to accept a certain level of moderation/sacrifice for the greater good of the society.

The other possibility is that they're all a bunch of nutjobs and will be looking for a fresh planet to colonize:

http://science.slashdot.org/comments.pl?sid=3166045&cid=41559185 [slashdot.org]

Re:Planet-based solar? (3, Informative)

Anonymous Coward | about 2 years ago | (#41559349)

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.

Population growth (1)

Tablizer (95088) | about 2 years ago | (#41559273)

with population controlled at a reasonable level, which should be expected from any advanced civilization?

It may not be politically "popular" for a given civilization to limit population growth. Imagine what the Republicans and Tea Party would do and say if somebody proposed government-enforced limits in the USA. And incentive programs are criticized as "poverty eugenics" by some on the left and "socialistic engineering" by some on the right.

Thus, expansion via space colonies may be more palatable to such civilizations.

Re:Population growth (4, Insightful)

the gnat (153162) | about 2 years ago | (#41559321)

Imagine what the Republicans and Tea Party would do and say if somebody proposed government-enforced limits in the USA.

Why pick on the Republicans here? I'm relatively liberal, and I know plenty of other liberals who would be just as outraged.

Re:Population growth (1)

GameboyRMH (1153867) | about 2 years ago | (#41559343)

I contend (above) that such a civilization would never reach the level of advancement necessary. They'll destroy themselves (either in one big spectacular event or by wasting resources/political will on war over the long term and "die in their cradle"), or deplete their planet's resources with no backup plan.

Re:Population growth (1)

zlives (2009072) | about 2 years ago | (#41559471)

"expected from any advanced civilization"... we are not there yet

Re:Population growth (1)

GameboyRMH (1153867) | about 2 years ago | (#41559531)

Nope we sure aren't.

Genuine excitement (1)

Shrike82 (1471633) | about 2 years ago | (#41559095)

This is the first time in a very long while that I've read a /. story that's gotten me excited. The idea that we could find evidence of a Dyson sphere is quite crotch-tingling for a fan of science fiction like myself!

Of course there's the problem of how we can be sure any evidence we see is actually a constructed sphere and not a freak natural occurrence, or something that we simply don't understand or haven't envisaged at this point. Still, any data that showed a "should-be-visible" star radiating heat but not light is something of note. Hell, it would give us something to start beaming signals at like mad in the hope of a return at the very least. Lets just hope it's within X light years, where X is less than half my remaining lifespan so I can catch the "Hello? Who the fuck are you!?" signal from the big blue people on Pandora.

Re:Genuine excitement (0)

Anonymous Coward | about 2 years ago | (#41559353)

This is the first time in a very long while that I've read a /. story that's gotten me excited.

Apparently you didn't read the "or vagina" article from a few months back...

Runs out of energy? (1)

Rik Sweeney (471717) | about 2 years ago | (#41559103)

I thought energy couldn't be created or destroyed, so the energy on this planet is pretty much constant?

Re:Runs out of energy? (5, Informative)

Errol backfiring (1280012) | about 2 years ago | (#41559289)

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).

Re:Runs out of energy? (1)

Half-pint HAL (718102) | about 2 years ago | (#41559335)

Energy and matter are interchangable. The plan is constantly gaining matter and energy from space (sunlight, starlight, cosmic rays, meteorites) and is also constantly losing matter and energy to space (evaporation of the upper atmosphere, radiated heat, leaked radio waves). The amount of energy+matter in the universe is constant, but the amount on any given planet is constantly changing.

Re:Runs out of energy? (1)

Daniel_Staal (609844) | about 2 years ago | (#41559395)

That's over the entire universe. It's quite possible for any subset of the universe to gain or loose energy, by sending it outside the subset.

Also, just because the energy exists doesn't mean you can use it.

Re:Runs out of energy? (1)

i kan reed (749298) | about 2 years ago | (#41559457)

Logical failure on your part: "On this planet"

Usable energy like fossil fuels are used, the energy goes to higher entropy state: i.e. heat.

Heat in the atmosphere radiates out. Total energy on the planet: lower.

Re:Runs out of energy? (1)

prefec2 (875483) | about 2 years ago | (#41559519)

It can be created (sort of) by fusion or fission. However, the matter + energy are fixed. So you can convert mass to energy causing to be more energy in the unsivers and less matter. However, energy cannot be destroyed or created as such, it is converted to or from matter.

So why can't we do it? (1, Interesting)

jtseng (4054) | about 2 years ago | (#41559107)

I suspect at this point humanity, as a collective whole, is still too small-minded to consider such an endeavor. Our politicians are narcissistic/sociopathic, and private industry would want it to be profitable.

*sigh*

Re:So why can't we do it? (4, Insightful)

Zontar_Thing_From_Ve (949321) | about 2 years ago | (#41559235)

I think you are 100% correct, but it's not just politicians who are small minded. Here's an example. I work in IT as a Linux System Administrator. One of my colleagues is not only extremely smart and one of the most knowledgeable IT guys I've ever worked with (he is like a living set of man pages), he is into sci fi. He feels very strongly that we have more pressing needs at home in the USA than to spend almost any money on NASA. I mean, he is the exact kind of guy who I would expect to be in favor of building a moon base. When guys like him won't even back NASA, there's really no hope for the USA to ever do anything useful in space in our lifetime unless it becomes a national security concern. But in direct response to your suggestion, I want to see a moon base first and a manned expedition to Mars before we try something massive like this. It's a "walk before you run" kind of thing.

Re:So why can't we do it? (1)

Intrepid imaginaut (1970940) | about 2 years ago | (#41559237)

Build a Dyson sphere? We haven't anywhere near the technical, scientific, or engineering capability to even begin contemplating that scale of ultraconstruction. Maybe in fifty thousand years or so. Which is fortunate since we have no need to build anything of the sort. Lets start small and pave over Saturn. Seriously. :D

From what I can tell the astronomers are looking for heat sources without a corresponding light source. I have my doubts but they would be purely speculative, if such a sphere is found what a spectacle it would be.

Re:So why can't we do it? (0)

Anonymous Coward | about 2 years ago | (#41559295)

why does everyone think profit is evil?

Re:So why can't we do it? (2)

Daniel_Staal (609844) | about 2 years ago | (#41559439)

It probably would be profitable, in small sections. (The original 'Dyson Fleet' version.) If you have the tech to put up orbital solar at reasonable cost, it's probably profitable to put up more and more orbital solar plants as your race grows.

Re:So why can't we do it? (1)

prefec2 (875483) | about 2 years ago | (#41559461)

Because it is totally insane to build such thing. It is much more reasonable to build collectors for sunlight based on earth. There is plenty of energy available based on that technology, which will fuel us for the next million years. Beside that, building a Dyson sphere in the right size so that we could live on the inside must be almost as big as Earth orbit. The sphere surface size is approx. 281176811992656000 km even if the collector would require only a millimeter think foil to be useful, you must provide 2811768119926.56 km of material. Total Earth volume is 1083002572572 km. So you need 2.6 Earth size planets to build it. Considering that we required quite some time to dig up some parts of the upper km of our planet (ca. 100 years), I assume it is completely impossible with present technology to even try to do it.

massive amounts of deliberate engineering (1)

Anonymous Coward | about 2 years ago | (#41559119)

'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.'"

You mean, similar to what would be required to build a Dyson sphere?

What would you get from a massive amount of accidental engineering?

If they have the tech to build it, do they need to (2, Interesting)

Koreantoast (527520) | about 2 years ago | (#41559127)

Wouldn't a civilization advanced enough to pull off an engineering feat like a Dyson Sphere also have advanced their engineering sufficiently to find more efficient power sources?

Re:If they have the tech to build it, do they need (0)

Anonymous Coward | about 2 years ago | (#41559259)

On a cosmological scale, there aren't power sources that are more efficient than a star. Maybe a different type of star, if so.

Re:If they have the tech to build it, do they need (1)

Anonymous Coward | about 2 years ago | (#41559403)

On a cosmological scale, there aren't power sources that are more efficient than a star. Maybe a different type of star, if so.

OTOH many things are pretty inefficient on a cosmological scale. The suns energy outbut per cubic meter (Or cubic feet.) is on the same level as a compost. It's just so much larger. We can already build power sources way more efficient than the sun. We just can't do it on the same scale.

Re:If they have the tech to build it, do they need (0)

Anonymous Coward | about 2 years ago | (#41559391)

Our Sun puts out 386,000,000,000,000 Terawatts and has another 4.4 billion years to go in its main cycle. Our sun is tiny too. It's a speck of dust compared to VY Canis Majoris [wikipedia.org] .

How would one get more power than that?

That is a big if. (1)

jellomizer (103300) | about 2 years ago | (#41559129)

The Dyson sphere is a massive engineering project. It would take a very very advanced civilization to complete it, using a lot of energy just to build it, taking a long time to do such work. Chances are they will kill each other off before they did such a project.

Re:That is a big if. (0)

Anonymous Coward | about 2 years ago | (#41559247)

The Dyson sphere is a massive engineering project. It would take a very very advanced civilization to complete it, using a lot of energy just to build it, taking a long time to do such work. Chances are they will kill each other off before they did such a project.

That is an anthropomorphism of sorts. Just because life as we know it have a tendency to kill other living things doesn't mean that this is a trait that exists in a life form evolved or constructed on another planet. On the other hand they might not even feel the need to survive as a civilization and could just as well decicde to collectively die instead of building a Dyson Sphere for some reason that would seem completely alien to us.

CMBR (0)

Anonymous Coward | about 2 years ago | (#41559143)

'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.'

It's unlikely that a civilization intentionally would hide unless they were familiar with reasons to hide. That means that an intentionally hidden Dyson Sphere would be an indication of a highly technologically advanced civilization that is socially unadvanced. While possible it seems unlikely.
On the other hand we are talking about a civilization that have gone through a major energy crisis. It may not think that it can afford to let all that mid-infrared energy go to waste.
Any sufficiently advanced civilization is indistinguishable from cosmic microwave background radiation.

Existential Question (-1)

Anonymous Coward | about 2 years ago | (#41559161)

Would a planet full of niggers even advance beyond the wheel, much less building rockets and building Dyson Spheres?

Blocking light (1)

Kjella (173770) | about 2 years ago | (#41559167)

'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.'"

If a civilization with a Dyson sphere has any reason to hide, it's probably for a civilization with interstellar flight and then I'd think you'd quite easily find the black spot. Unless you assume they got a system to route or absorb/emit starlight from one side of the sphere to the other. But since we're far into science fiction land already, why not...

Re:Blocking light (1)

jovius (974690) | about 2 years ago | (#41559313)

More likely some other civilisation is hidden beyond our observable bubble of universe of about 14 billion light years in their own bubble - which can be billions of billions of light years away and practically unreachable.

First space-faring race = a bunch of nutjobs (3, Insightful)

GameboyRMH (1153867) | about 2 years ago | (#41559185)

I was watching that Riddick movie with the Necromongers the other day and I realized that the concept was actually very realistic. What kind of society would get into space first? The ones that put a high priority on space exploration. And what kind of civilization would do that just for the heck of it before any others? The ones that have some irrational reason to do it driven by some kind of religious fervor. While the "Star Trek like" science-driven societies pace themselves in a sensible manner, the religious nutjobs would throw every single resource their entire civilization could at getting into space to please their space deity or whatever. If there's an advanced space-faring race out there you probably want to steer clear of them.

See also: The Irkens from Invader Zim

Re:First space-faring race = a bunch of nutjobs (4, Interesting)

PPalmgren (1009823) | about 2 years ago | (#41559269)

That's only given all civilizations started at roughly the same time. However, this isn't Civilization V. A space-faring race could have formed a contigous civilization several hundred thousands or millions of years ago, not a couple thousand years like ours. It might be the natural evolution of things at that point.

Re:First space-faring race = a bunch of nutjobs (0)

Anonymous Coward | about 2 years ago | (#41559385)

not a couple thousand years like ours

Yeah it's only been around for like 2012 years.

Re:First space-faring race = a bunch of nutjobs (1)

GameboyRMH (1153867) | about 2 years ago | (#41559389)

True it's possible that the Starfleet Federation could get a big head start on the Necromongers/Irkens, but the reverse is also true...all up to chance really, and calling it 50/50 is probably optimistic given the huge time penalty of "reasonableness" or worse yet "hesitance and bickering."

Re:First space-faring race = a bunch of nutjobs (2)

SmurfButcher Bob (313810) | about 2 years ago | (#41559359)

So you're saying that at least one alien theology states that their deity will be found in a human's anal cavity?

Re:First space-faring race = a bunch of nutjobs (2)

Mike Buddha (10734) | about 2 years ago | (#41559399)

Yeah, that makes sense, until you look at reality. The European drive to colonize paid a lot of lip service to religion, but in the end it was the almighty gold piece that drove the conquest. How do we justify the cost of putting a person on the moon? By the economic benefits of the scientific discoveries and the resulting technology created.

Economics drives our pushes forward, not religion. Scarcity is the underlying force.

Efficiency (1)

Anonymous Coward | about 2 years ago | (#41559201)

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

Time to Panic? (0)

Anonymous Coward | about 2 years ago | (#41559257)

If we find a string of completed dyson spheres with some partial ones being closer to us than the completed ones.....

What if an alien rouge AI is multiplying itself and building dysone spheres in it's wake by busting up planets for raw materials.....

Our only hope would be that they would start with either mercury or jupiter first giving us enough time to get of earth before the planet gets dismanteled by so many robotic drones....

energy leakeage (3, Insightful)

demonbug (309515) | about 2 years ago | (#41559283)

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.

Right, because there's no way a civilization advanced enough to build 282743338860000000 square kilometers of solar panels is going to be able to build solar panels capable of absorbing and using mid-infrared light (heat). If the supposition is that they inevitably build Dyson spheres to capture all of the available energy coming off their star, why would they let a whole bunch of it escape as heat?

Seems like a giant waste of time and money, but I suppose they will be generating useful data while they look. Still, their chances of finding one are likely ludicrously close to zero even if one does exist. I also find the whole premise to be rather poorly thought out, I have to admit; even if a civilization is capable of building a Dyson sphere, I'm not sure it makes any sense to actually do it.

Re:energy leakeage (4, Informative)

Hentes (2461350) | about 2 years ago | (#41559371)

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.

Pretty much impossible, IMHO (1)

Khyber (864651) | about 2 years ago | (#41559319)

Dyson Spheres are practically an impossible thing to build. First off, you'd need the energy to build such a system around the star. Secondly, you would need the MATERIALS (and even with Energy-Matter conversion tech, the issue again is energy.) Thirdly, you'd need the TIME.

These three things have been against us for pretty much any project our species has ever attempted, and I would readily assume the same constraints would apply to other civilizations attempting a Dyson Sphere. Given the sheer scale of the project, I would have to say it is nigh impossible.

Re:Pretty much impossible, IMHO (1)

Reschekle (2661565) | about 2 years ago | (#41559489)

Regarding time: I don't think you have to build the entire thing all at once. You could construct it over the course of centuries or millennia while still benefiting from the incremental energy output gains you achieve as the build is in progress.

Star Trek covered this (1)

Anonymous Coward | about 2 years ago | (#41559357)

If a civilization has the ability to construct a Dyson's Sphere they are probably so advanced they wouldn't need to construct it in the first place. (From Star Trek TNG, not a direct quote)

Errmmm... (1)

Nevynxxx (932175) | about 2 years ago | (#41559365)

'but it requires massive amounts of deliberate engineering across an entire civilization.'

And a Dyson Sphere doesn't?

Food for thought... (2)

Troyusrex (2446430) | about 2 years ago | (#41559373)

The Templeton Foundation [wikipedia.org] that funded this research is often highly criticized for religious bias. It's kind of like oil companies providing money for research. It might be good in that it provides research funding but there's always a worry that the money from an organization with a particular point of view might skew the science.

I'm not saying that this invalidates the research, but it does cast some doubt on it and the reasons it is being done.

Fusion Reactor (1)

RichMan (8097) | about 2 years ago | (#41559421)

Why wrap your world around a giant fusion reactor that requires a massive clearance space if you can make smaller more portable more mobile units?

That Dyson is something else (1)

Anonymous Coward | about 2 years ago | (#41559445)

Never thought he could top that fan with no moving blades, but harnessing all of a star's energy output? Very cool.

Interesting, but for other reasons (2)

larry bagina (561269) | about 2 years ago | (#41559455)

Dyson spheres are an interesting thought experiment but fairly stupid when you think about the logistics (as mentioned in previous comments, so I won't get into it). At least on our scale. Just as elctrons orbit the nucleus, moons orbit planets, planets order stars, stars orbit the galaxy center, galaxies orbit the giant turtle and form supergalxy clusters... There's no reason to say intelligent life composed of cells composed of molecules and atoms couldn't also exist at a larger scale. (Ask the symbiotic bacteria in your gut sometime). And intelligent life at a larger scale certainly could biuld a dyson sphere. Hell, maybe we are part of the dyson sphere.

Dyson Sphere: How useful is it? (2)

scorp1us (235526) | about 2 years ago | (#41559459)

Ok so somehow you get enough materials and energy to shape it into a sphere. That's an impossible task, but then it's somehow even more impossible that they use radiators to disperse the heat? I mean when you're talking about impossibility, it doesn't matter if it's squared or cubed. Then once you have this shell of solar collectors, how do you get the energy inside of it? You basically have a Faraday cage.

Also, why the fuck? Any significantly advanced civilization would use gravitational engines. That is either under direct or natural control, they would set up a oscillation system between multiple orbiting bodies where they can harvest energy without needing fusion. Instead of lighting up the solar system, they'd go invisible, detectible only via gravity waves which to date, are impossible to detect. At a minimum, significantly harder to detect.

Silly waste of time. (3, Interesting)

Lumpy (12016) | about 2 years ago | (#41559463)

First off a dyson sphere does not take into account the MASSIVE amount of praticle energy that is coming off the star. the Stellar wind on that scale would be immense. Secondly, Orbits are not magical. a dyson sphere is unstable and will either wobble and start to collapse into the star, or rip apart due to the uneven gravity well. Just the technology to even be able to have the ability to think of building a Ringworld, something far, far, FAR easier than a Dyson sphere is so mind bogglingly compex that it collapses in upon it's self.

Sorry but it's a waste of time we might as well look for civilizations that are harvesting black holes to power their space ships.

Disruptive bluffing (4, Funny)

cellocgw (617879) | about 2 years ago | (#41559485)

Quick! Let's build a giant IR emitter w/ some filters to produce the same spectral curve as a Dyson sphere. All those not-quite-advanced societies out there will detect it and run screaming from our perceived galactic-overlordishness.

Didn't someone run the numbers on this? (1)

jayhawk88 (160512) | about 2 years ago | (#41559497)

...and determine that the energy requirement for building and maintaining even a partial Dyson Sphere was so astronomically high that even assuming 100% energy collection from the star, it would never be feasible to build?

completely ridiculous (0)

slashmydots (2189826) | about 2 years ago | (#41559501)

"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."

Or technology we don't know about. In fact, that really blows apart this entire project. On Stargate Atlantis, aliens invented ZPM - zero point module that creates a sort of mini-singularity with no gravity that generates energy. The way humans right now would harvest energy from a star would be a lot different than a million year old civilization so this is a gigantic waste of time and money.

Still see light... (1)

beaverdownunder (1822050) | about 2 years ago | (#41559515)

If we can assume that such a civilisation would still want sunlight to hit their planet, then any Dyson "sphere" would need to have a 'gap' around the plane of the inhabited planet. This wouldn't be perfect, and there would still be a bleed that would at distance be observable from any angle.

Wouldn't this money be better served feeding starving kids in Africa? (Just sayin'...)

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