Could Humanity Ever Really Build a Dyson Sphere?
Out of Our League
Imagine sucking up the immense energy output of the Sun by totally encapsulating it with a vast mega-structure made of solar panels—that is the Dyson Sphere.
Since solar energy's discovery almost two centuries ago, harnessing the immense power of the Sun has been the subject of many research endeavors. As mankind's energy consumption just keeps rising, there will come a time where we'll have to build ludicrously large scale structures like the Dyson Sphere to quench our daily energy needs.
Or develop an, as yet unknown, method of producing energy that doesn't require a lot of space.
But let's back up. In 1960, astrophysicist Freeman Dyson popularized this idea—speculating that a technologically advanced race would seek to harness their sun's immense energy by encircling it with a sphere-like object.
"One should expect that, within a few thousand years of its entering the stage of industrial development, any intelligent species should be found occupying an artificial biosphere which completely surrounds its parent star," Dyson wrote in his 1960 Science paper.
Obviously, this is way, way beyond our capabilities. Still, we have to ask ourselves this: Would it ever be feasible?
The U.S.S. Enterprise encounters a Dyson Sphere in Star Trek: The Next Generation. Paramount.
Dyson Swarm
As the latest episode of PBS Space Time explains, making a single vast mega-structure encapsulating the Sun is structurally impossible.
We'd be faced with gravitational stresses, structural in-habitability, and location instability. Moreover, we currently don't have the engineering capabilities nor the materials to pull this off.
But collecting the entire output of our home star may still be the smart choice. What we do instead is to build a Dyson "swarm," and not a Dyson "sphere." The Dyson Swarm is made up of one-kilometer (0.6 mi) solar panels that orbit the Sun in hundreds of stable criss-cross patterns.
Basing what is possible on current thinking puts a vast amount of things in the "impossible" sphere! Take it back a few decades and very few would have thought flat screens, wrist portable communicators and eye glasses that could access more literature than the British library holds to be impossible. Technology becomes outdated fast and the pace is increasing with far more now possible and in fact relatively easy to do than ever previously thought. Give it time and ways to make Dyson spheres and other even greater things will become possible!
I agree, 20 years ago nobody would have ever believed that we would be able to send gram-scaled nanocrafts to proxima centauri at 1/5th the speed of light. Our technology is evolving at a superfast pace. Ofcourse a Dyson sphere is much more advanced than that but I wouldn't be surprised that we could actually build one somewhere in the second half of this millenium.
Just wish I could be around to see what the human race becomes capable of in 500 - 1000 years! Assuming we have all become peaceful enough to co-exist nicely! :)
Yeah, that's a big if you mentioned there haha. And I agree that I would love to see our evolution the next millenium, time to figure out some of that "Ghost in the Shell" technology! :)
Indeed, it would be so easy if politics and religion were out of the way though.
Ah yes, "Ghost in the Shell" tech that would be awesome, I do particularly love the idea of just plugging something into the back of my head and being live on the internet, would be able to work so much faster and do so much more!!! :)
I think about the resorces we would need to build a Dyson sphere, can our solar system handle that?
Well, obviously we need to be able to travel to other solarsystems before we can even think of building a Dyson sphere. So we could just mine the resources of barren rocks first and then use those to build it. What I would like to know is how long it would take to build (using future technology ofcourse).
It's not obvious at all that we need so much material. That's just one of those weird cascades of misinformation from people playing telephone with the facts...
Dyson originally did some back of the envelope work to see how thick one could be build at 1.0 AU (not a literal solid shell, but an average thickness of a 'shell' of a vast number of habitats and so on) and came up with 3 meters. Sci-fi authors misinterpreted that and started designing vast impractical spherical habitats sort of like a Bernal Sphere but bigger... This was never supported by credible scientists.
The modern conception from Anders Sandberg and Stuart Armstrong as cited by the video is actually of a very thin one, based on another back of envelope calculation: Mercury's metal content. If you disassembled Mercury and made a sphere from its remains (just the metal part), at 0.3 AU, the average thickness would only be about twice that of household aluminum foil.
Except their paper doesn't say why it would need to be even that thick -- they were actually just wildly overestimating to be conservative. Graphene is only a tiny fraction of that thickness. You would need to layer 1000 sheets of graphene to be heavy enough to not be blown away by the sun's light pressure. Or you could have one layer graphene plus 1000 times as much metal.
The result is called a Dyson bubble... Much lighter, and doesn't orbit (so there is no need for a criss-cross pattern) because it is held up by the light pressure.
Wow , mercury didn't know about that. That's crazy cool. Thanks.
The amount of resources needed has been greatly exaggerated in the media and in popular science fiction. In reality, a 1.0 AU bubble-type sphere would require around the mass of the second largest asteroid, whereas cutting the size down to the orbital distance of Mercury would reduce the cost to a tenth of that. (Really, you'd want to bring the collection surfaces as close to the sun as possible.)
And remember, it's a power collector, not a habitat -- you could beam the energy out to habitats wherever you want throughout more distant space. Smaller spinning containers are much more efficient for producing habitable area, thanks to the square-cube law, and much easier for controlling things like weather.
More likely than putting that all towards landmass production, you'd put the power to work on some scientific project or another. I am a fan of the idea of using it to power vast fleets of computers, and using that to crack hard problems like discovering a cure for cancer.
A Dyson swarm is a subcategory of Dyson sphere. The swarm is oriented around the Sun (or star) in a spherical shape.
The idea of a solid spherical object or single 'Ringworld' like habitat is not what Dyson originally had in mind when he proposed looking for these throughout the cosmos. In fact, he was thinking that the civilization would gradually create more and more orbital habitats, each with its own set of solar collectors. He estimated that disassembling all of the planets in the solar system would yield enough for around three meters of average thickness. That is, you could have thin solar mirrors covering most of the area, with thick, well shielded habitat areas and buildings on the inside in smaller regions.
A more modern concept of Dyson sphere called a Dyson 'bubble' is much more easy to make because it sticks to a closer distance from the Sun than Dyson's 1.0 AU estimate, and it uses a much thinner type of solar panel that uses much less materials, being just a few microns thick. Today we know there is a special substance called graphene that can support a 4 kilogram object in a 1 square meter sheet, despite being a nanometer thick, weighing 0.77 milligrams. The sun puts out a constant amount of light, which repels objects at an acceleration rate equivalent to the gravity times about 0.78 grams per square meter, so the optimal average weight of a stationary (nonorbiting) power collection station would be about 1000 times that of a sheet of graphene. That extra mass could be something like a thousand layers of graphene, or (to save carbon) could just be metal or glass of a type that is abundant throughout the asteroid belt.
The amount needed to build a structure of this scale, with a distance of 0.3 AU from the Sun, is around a tenth that of the second largest asteroid. That's big, but not nearly as big as people often claim. The video claims that it would be 'all the terrestrial mass in the solar system', but this is simply not supportable -- we are talking about a fraction of 1% of a terrestrial planet. On the other hand, it does give us enough energy to disassemble entire planets in a short time frame -- if we feel the need to do so.