Could We Build a Dyson Sphere Around the Sun Using Jupiter for Raw Materials? (futurism.com) 102
Long-time Slashdot reader schwit1 shared this report from Futurism:
We'd need an astronomical amount of resources to construct a Dyson sphere, a giant theoretical shell that would harvest all of a given star's energy, around the Sun. In fact, as science journalist Jaime Green explores in her new book "The Possibility of Life," we'd have to go as far as to demolish a Jupiter-sized planet to build such a megastructure, a concept first devised by physicist Freeman Dyson in 1960...
Not everybody agrees that constructing a Dyson sphere would end up being such a huge undertaking. In an interview with Green, astrophysicist Jason Wright compared such an effort to [the city of] Manhattan, a human and interconnected "megastructure," which was constructed over a long period of time, bit by bit... "It's just every generation made it a little bigger...."
"If the energy is out there to take and it's just gonna fly away to space anyway, then why wouldn't someone take it?" Wright told Green.
Not everybody agrees that constructing a Dyson sphere would end up being such a huge undertaking. In an interview with Green, astrophysicist Jason Wright compared such an effort to [the city of] Manhattan, a human and interconnected "megastructure," which was constructed over a long period of time, bit by bit... "It's just every generation made it a little bigger...."
"If the energy is out there to take and it's just gonna fly away to space anyway, then why wouldn't someone take it?" Wright told Green.
Do the math (Score:5, Insightful)
There is not enough material in all of the planets combined.
Re:Do the math (Score:5, Funny)
You just have to transmute the diamond core of Jupiter into unobtanium in order to have a material with enough tensile strength that you can make the shell thin enough to work. Oh ye of little faith, call on your friendly neighborhood alchemist!
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My calculator doesn't have enough significant digits to compute this. Smearing Jupiter out into a Dyson sphere ends up under 1mm in thickness. Need a better calculator to get the actual number.
Re:Do the math (Score:5, Informative)
Wolfram says smearing Jupiter into a Dyson sphere will be 102nm thick. The light will pass right though.
Re: Do the math (Score:4, Funny)
Fun job! Sounds like something xkcd would come up with.
Also, Jupiter is mostly hydrogen and helium. Tough to build something from that.
Oh, we're working on fusion, right? Okay, so in 10y maybe.
Re: Do the math (Score:1)
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At what radius? Jupiter's orbit? I'm pretty sure a Dyson sphere at Mercury's orbit would be a lot thicker than a micron.
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I would assume Earth's orbit. That's the "sweet spot" for supporting Earth's life forms. Any closer and it would be too hot all of the time. Further away would be too cold. This is of course assuming the capturing of all of the Sun's energy and using it distributed around the sphere would translate to the same amount of energy currently captured by Earth's tiny sphere.
Re: Do the math (Score:2)
At what orbital distance? 1mm assuming it's all solar panels, and each panel flies free, a Dyson swarms not a sphere (you transmit energy around via microwaves or lasers) would work although it would take a long time to transmute the elements of Jupiter to the right mix.
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Is that 102nm thick of scrith, the unobtainium in larry niven's ring world?
Re:Do the math (Score:5, Informative)
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equivalence.
a flea approaching an elephant.
having aspirations of intimacy without consent.
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Re:Do the math (Score:5, Interesting)
That depends on just how literally you take "Dyson Sphere". There's no requirement for complete coverage. Certainly you'll need some materials to live on. Etc. But a nest of orbits with massive objects at evenly spaced points along each orbit and webs of energy receptors fanning out from them could also be considered a Dyson Sphere. After all, NOTHING is going to give you complete capture of the sun's energy, so when you approach that, you're within the area of what a Dyson Sphere means.
Note that you still won't get close to complete coverage, but you would significantly shift the sun's spectrum (as seen from outside) towards the red. The way to detect this from outside would probably be something like a bi-modal spectral peak, with one peak significantly redder than the other.
The variation of this idea that I like best is called Topopolis, or sometimes "cosmic spaghetti". It's a really long tube perhaps a few miles in diameter. It rotates for gravity. And it just keeps going. It could loop several times around the Sun. It could have segments that don't rotate (fancy connections would be needed) and fork in those junctions. It could have a section that was headed straight into outer space, and be an electromagnetic catapult several miles long (say one Earth diameter). This would allow mild accelerations to reach quite high velocities.
(If you want one earth gravity, and don't want to rotate faster than 12 rpm, you need a a radius of about 140 miles. But I think that with the larger diameters you could get away with faster rotations without any problems, and also suspect that 3/4 g, or even 1/2 g wouldn't cause any real problems...unless, of course, you wanted to come back to Earth.)
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It doesn't matter if your Dyson sphere is really just a ring, there still wouldn't be enough material to build such a ring, let alone an actual *sphere*.In our imaginations, The distances in space are vast. Fortunately, there won't actually be a serious attempt to build such a thing, because there isn't enough money in the entire world to finance the project.
Dyson Sphere bad Idea (Score:4, Informative)
That depends on just how literally you take "Dyson Sphere".
The purest sense of the idea, a uniform spherical shell around the sun, is actually a really bad idea because it is gravitationally decoupled from the sun and so would need thrusters to maintain its position.
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Why would you even want something like that though? It's technically impressive but we have no use for that amount of energy.
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I get what you are saying, but harnessing all the energy radiated by a star...
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To power all the thrusters, obvi.
buuthandi, according to Howard Taylor (Score:2)
The long-running space-opera web comic Schlock Mercenary [schlockmercenary.com]
The notes for https://www.schlockmercenary.c... [schlockmercenary.com]">the April 21, 2002 episode give a fine description:
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Lost most of the first sentence while fighting with slashdot's "prove you're a human and "your connection is secure" tooling. Should have been (something like):
The long-running space-opera web comic Schlock Mercenary included aliens living on dyson spheres of a more achievable construction: Habitats not orbiting, but hovering on light pressure, suspended beneath large light sails / solar collectors.
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That doesn't really sound practical. If you aren't orbiting, then the light pressure wouldn't be sufficient to hold you up unless the average g/cm^2 was really small. You could use light pressure to reduce the orbital speed, though.
OTOH, Schlock Mercenary isn't supposed to be sensible. But when you try to drag it into a "slightly more practical" discussion that matters.
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That doesn't really sound practical. If you aren't orbiting, then the light pressure wouldn't be sufficient to hold you up unless the average g/cm^2 was really small.
Huh?
Using the sun for a reference and Earth's orbital radius as a good distance for the habitats - nice temparature with only a little greenhouse effect:
The sun's gravity at Earth's orbit is only 0.0006g. A solar sail of 800x800 meters produces about 1.1 pounds force at Earth's orbit. So it would take only 640000 * 0.0006 / 1.1 = about 149 squ
Grading my homework. (Score:2)
Howard Taylor did his homework.
But I made an error in mine. Make that: ... the light pressure of the sun at that distance could levitate about 1.9e21 pounds. The mass of the Earth is about 1.317e25 pounds, so you could only levitate about 0.000144 of it, about one part in 7,000.
Still enough for habitats totaling a VERY GREAT MANY times the land area of all the Earth's continents, of course.
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Re:Do the math (Score:4, Funny)
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"There is not enough material in all of the planets combined."
It would be against the law anyway.
Betteridge's law of headlines with a question mark.
Now I'm asking myself, why I clicked on this crap.
Re: Do the math (Score:5, Funny)
We'll do it at night.
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That depends entirely on how large the sphere is, and how thick. You can do the math with any values you choose, and pick your favorite fantasy scenario. How about a sphere at the orbit of Mercury, with an Earth-facing hole in it? It'll need active stationkeeping to hold it in place anyway, so keeping it pointed at Earth won't be a big deal. This'll run a bit hot for photovoltaics, but if you harness the heat flux itself it'll generate a fantastic amount of power!
Do the reasoning? (Score:5, Interesting)
Do the math...There is not enough material in all of the planets combine
It never ceases to amaze me that people keep spreading Dyson sphere's as something that's even desirable. To the extent that they use the lack of evidence for them in the galaxy as a meaningful indicator of the lack of intelligent life.
A Dyson Sphere is the equivalent of ancient humans discovering an entirely forested North America, and saying "Hey, let's light it on FIRE! All of it! And then just think how we can we can all of us gather around the coast to keep warm from it". The worst thing we can do as a species is let the Sun burn. It will use up the very small fraction of Hydrogen it has in its core, then expand and kill us all.
That said, there is no need for energy of that scale. It is wasteful like burning North America would have been wasteful. The Sun is one of the least efficient creators of energy there is in terms of energy created for size of reactor. It produces 270 milliwatts of power per cubic meter of volume. I'm pretty sure any future fusion tech will be better than that. The earth currently produces about 368,000 MW of power from nuclear reactors. If those reactors were the size efficiency of the Sun, they would take up 1.3x10^12 cubic meters (1,362 cubic kilometers).
The best thing we can do, if we have that kind of mega-engineering capability, is to snuff out the sun and use its fuel to power the Earth for a trillion years.
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It never ceases to amaze me that people keep spreading Dyson sphere's as something that's even desirable. To the extent that they use the lack of evidence for them in the galaxy as a meaningful indicator of the lack of intelligent life.
A Dyson Sphere is the equivalent of ancient humans discovering an entirely forested North America, and saying "Hey, let's light it on FIRE! All of it! And then just think how we can we can all of us gather around the coast to keep warm from it".
Exactly.
Everyone presumes that an "advanced" civilization will want to harness as much power as possible, and that they'll just want to keep adding zeroes to their power output until they can't any more. To what end? So that they can multiply themselves endlessly and occupy as much physical space as they can? That is the thinking of an insect; indeed, it's the thinking of a bacteria.
I suppose the standard reply to this would be "more power means more computational power". But this is a hand-waving sort
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Transmutation, not Mass the Problem (Score:2)
There is not enough material in all of the planets combined.
Whether that is true depends on a lot of different variables including how close to the sun you can build the sphere and how thin you can make it. However, since Jupiter is 90% hydrogen and 10% helium clearly we are using some magic device to transmute that into the heavier elements needed to build the sphere and with that level of tech making a thin enough sphere, close enough to the sun with thrusters to keep it in place (since a sphere is a really bad design and gravitationally decoupled) is just a bit
Jupiter (Score:4, Interesting)
Destroying Jupiter and building the Dyson Sphere will bring a whole other set of issues. It will disrupt the orbits of all other planets, flinging them all over the place. Maybe even destroying work on the Sphere as it progresses.
But I guess if you can even attempt this, maybe you can mitigate these issues :)
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Not to mention we have Jupiter to thank for helping (usually) to divert [earthsky.org] all kinds of space stuff away from us.
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Not to mention we have Jupiter to thank for helping (usually) to divert [earthsky.org] all kinds of space stuff away from us.
It if were not for Saturn, Jupiter likely would have diverted the big glob of space stuff we live on, right out of the Solar System.
https://www.youtube.com/watch?... [youtube.com]
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Consider the scope of 'disassembling Jupiter to make a start on Dyson Sphere'.
Well before you start on that, wouldn't you presumably disassemble all sorts of other stuff for smaller projects?
Odds are, by the time you seriously start draining Jupiter, you've already cleaned up all that "space stuff", not to mention doing stuff like fixing the orbits of the planets however you like.
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Odds are, by the time you seriously start draining Jupiter, you've already cleaned up all that "space stuff", not to mention doing stuff like fixing the orbits of the planets however you like.
In the book, The Ring of Charon, that's pretty much what the invaders start doing to the solar system. They land planet-destroying craft which start disassembling planets and moons and whatnot, to turn it into a Dyson sphere (the protagonists figure out).
Part of the book, and its follow on, The Shattered Sphere involv
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no one knows how the remaining humans get out of the pickle of having half the people in our solar system, and the other half unknown light years away, getting back together and reconstituting what's left of humanity while stopping the beings intent on destroying the solar system.
Invisible hand of the market fixed it. Duh.
Re: Jupiter (Score:2)
Skip Jupiter.
We have to get better at converting energy to matter much faster, and matter to energy much, MUCH slower.
Easy to say, but hard to do.
But if we're imagining a Dyson sphere (hey, the vacuums work pretty well!), we can imagine a deeper knowledge of physics that will let us do it.
Heck, maybe energy>matter is the way we dissipate, maybe even store the excess energy.
You Already Solved those Problems (Score:2)
Not to mention we have Jupiter to thank for helping (usually) to divert [earthsky.org] all kinds of space stuff away from us.
Neither this, not the OPs problem will be a concern. If we can literally dismantle Jupiter then adjusting the orbit of a much smaller planet is peanuts not to mention deflecting tiny - by comparison - asteroids. Indeed, the first bodies used for building the sphere would almost certainly have been the asteroids since they have almost no gravity well thus there would be nothing to protect us from!
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For one thing, Jupiter is largely hydrogen, and that's a rather poor building material, so you'll probably need to burn it to get the energy to remove the rest of the stuff from Jupiter's gravity well. There are reason's Niven invented "scrith". He needed to make the "base-rock" implausibly thin AND strong. And he still didn't attempt a classic Dyson Sphere (solid shells). (Well, there are multiple problems with the naive implementation of a Dyson Sphere. So you need to revise the specs considerable to
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Well, clearly, the first step in building something out of Jupiter is to snuff out the sun so that the ambient temperature drops low enough for that hydrogen to be solid.
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More seriously, you want a Dyson Swarm (lots of independent satellites capturing as much of the sun's energy as possible), not a solid sphere. The natural place to put it (once geosynchronous earth orbit is full) is the asteroid belt. The natural thing to make it out of is the asteroids and eventually Mars, which aren't hydrogen. You don't get around to snuffing out the sun and building things out of hydrogen from the sun (and Jupiter) until everyone already lives in space, you've mastered fusion, and ev
Eat Uranus (Score:1)
The outer planets would probably be mined and converted first or in parallel, so they wouldn't be a problem. Whether it would affect orbits of the inner planets beyond correctable patterns, I couldn't say.
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Destroying Jupiter and building the Dyson Sphere will bring a whole other set of issues. It will disrupt the orbits of all other planets, flinging them all over the place.
Except for Europa I think they're all fair game to be turned into cement and rebar.
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Destroying Jupiter and building the Dyson Sphere will bring a whole other set of issues. It will disrupt the orbits of all other planets, flinging them all over the place. Maybe even destroying work on the Sphere as it progresses. :)
But I guess if you can even attempt this, maybe you can mitigate these issues
The funny bit is this "futurism" report is 60 years late to the party.
Wait until they get through the next ten years of thought on the subject and are only 50 years behind the times.
A dyson sphere is far less efficient than a dyson swarm, which would have the same energy harvesting capabilities and the same computational power, but require around ten orders of magnitude less material and energy to create.
A swarm has no requirement to be completed before it is usable.
It starts on the level of essentially a m
Re: Jupiter (Score:2)
If we achieve the technology to build a Dyson Sphere I think we can manage.
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But I guess if you can even attempt this, maybe you can mitigate these issues :)
I'm guessing if you could attempt this you wouldn't need to anymore since we'd be generating free energy from our own fusion reactors in everyone's basement.
SpaceX needs to expand scope first (Score:2)
Future refinements may lower resource cost (Score:2)
Not to mention, it'll likely be patchwork: the first massive chunk will be heavier and less efficient. Then technology will improve, and perhaps it'll be thinner and more efficient. Then it'll improve even more, etc. Not to mention, it need not be a total sphere at first. I don't think any of us can even fathom how or why humanity would need that much sheer mindboggling energy. It's like giving all the nuclear power in the world to an anthill at this point. By the time we can build a Dyson sphere, we'll pro
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it should NEVER be a solid sphere. And not just because there aren't enough building materials, (Which there aren't.) Also because you want clear paths in and out. And you're going to need to rotate pieces for gravity. it's better if their contact with non-rotating pieces is minimized. Et multitudinous cetera.
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"By the time we can build a Dyson sphere, we'll probably have......." have gone extinct
Could we? How about "should we?" (Score:1)
First thing that comes to mind: "What could possibly go wrong."
Re: Could we? How about "should we?" (Score:2)
Trigger warning: Scientist Jeff Goldblum. Again.
How about ... (Score:2)
we first worry about building a permanent settlement on the moon before we plan a Dyson sphere.
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No (Score:2)
We can't keep the roads in the world's most advanced countries in good repair even with readily accessible materials & relatively easy labor.
The Sun & Jupiter are, fortunately for them, safe from our stupidities
Re: No (Score:1)
No need. (Score:2)
The idea is based on two questionable premises: the need for absurd amounts of power and that gravity based stellar fusion is the optimal solution. The most important thing is being able to efficiently utilize the output from stellar fusion which varies based on it's mass and age. If it cannot be utilized directly then it seems likely that other forms of fusion will produce more optimal outputs as the reactions can be controlled. However, if you are a truly advanced civilization (mastery of quantum mechani
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It's all based on the idea that ringworlds/dyson spheres are orbitally stable. Neither are. No ring construct is (rings cannot "orbit").
absolutely brilliant!! (Score:2)
Because of that, it acts like a vacuum cleaner sucking comets, asteroids, and detritus out of our local system and preventing them from being captured by earth's gravity and destroying life on earth.
So, yeah, by all means. Just destroy Jupiter for raw materials.
Brought to you by the same people that are going to start deto
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The person who wrote this drivel is not a scientist - she's calls herself a "science journalist".
Those who can't do, teach. And, nowadays, those who don't know even enough to teach become special-topic bloggers... I mean special-topic "journalists". You know, like we see all the time with tech "journalists".
If we had the technology & resources.... (Score:1)
If we had the technology & resources, we wouldn't even need to do this. We would certainly be able to create our own portable mini–suns.
Hell we could probably do that soon...maybe its 50 years away...
The problem is... (Score:2)
In another time, they would've speculated (Score:2)
about reaching God with a hot air balloon.
These are fun math problems in a high school or college physics class, but speculation about building our very own alien megastructure right now is like the ancient Greeks speculating about nuclear fusion.
Not worth the investment! (Score:2)
Very doubtful - orbital mechanics (Score:2)
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Fun fact: ringworld and dyson spheres cannot "Orbit." They can spin, but they cannot maintain an actual, stable orbit.
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You can see a good discussion on quora (not the best source), but it's correct:
https://www.quora.com/Is-it-po... [quora.com].
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Nope (Score:2)
The human race cannot even get simple things done, like reducing CO2 output.
No we cant (Score:2)
We can’t even figure out how to automate delivery and factories how are we going to build a Dyson anything. Forget it.
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My Dyson Vacuum cleaner would like a word with you!
No. (Score:1)
And that's assuming we had the materials science to manufacture materials that could actually survive the construction process.
Ha! (Score:2)
Why? (Score:2)
Why?
No (Score:2)
We sure couldn't due to the amount of pressure the Jupiter atmosphere would impose on any resource collector we sent to harvest resources. Next question!
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What could go wrong? (Score:3)
... uhhhhhh, everything.
Ringworld (Score:2)
We could also build a ring, aka Ringworld. Easier to build and achieves many of the benefits.
Nope (Score:2)
No. And even when we could ... (Score:1)
... imagine the MASS generating so much gravity it WILL attract all other planets near to come crashing in. Neptune comes saying hello .....
The most important question is: why? (Score:2)
Net energy positive? (Score:1)
Even if you had a few spare accessible Jupiters made of the right material, how is mankind going to manage all that power?
We can already capture some of the sun's energy on earth. I accept Jaime's point that full coverage is infeasible. But that comes with its own questions anyway. just to put a few solar panels orbiting the sun (in an orbit of the same period as earth's) close enough to improve their energy output, but far enough away not to be incinerated. With the standard lunar-solar-farm idea's En
Re: Death Rays (Score:2)
If we captured the theoretical maximum amount of energy possible from the Sun, then subtracted the portion we would want to do stuff here on Earth...
Wow. That would leave a LOT of energy left over for making Death Rays. We could do a lot of interesting things, like obliterating neighbouring planetary systems to make something pretty for our telescopes to watch, or maybe adjust the Sun's galactic orbital path to move us away from hazards like potential supernovas, or move us closer to another star so we ca
And planetary orbits w/o Jupiter would be what? (Score:2)
Seems like a pretty big gap to fill no? That have any impact on the Dyson sphere and other planets?
sure, why not? (Score:2)
Absolutely. Let's allocate $10,000,000,000,000 per year for the project. Has to be all union workers, though.
Why am I even responding to this nonsense?! (Score:1)
This sphere would need to be significantly larger.
How many (panels) do you think would get installed before the first (panel) needs servicing?
I want the brain cells - that I wasted on this idea - back!
According to Bard, no. (Score:2)
Here's the prompt and Bard's response:
how much would a dyson sphere with the raidus of the Earth's orbit mass?
The mass of a Dyson sphere with the radius of Earth's orbit would be about 1.3 × 10^27 kilograms. This is about 100 times the mass of Jupiter, or about 0.01% of the mass of the Sun.
To calculate the mass of a Dyson sphere, we can use the following formula:
Code snippet
M = (4/3)R^3
Use code with caution. Learn more
where:
M is the mass of the Dyson sphere
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Not that I believe it's actually possible or that we'd ever do it.. BUT:
You don't have to build the shell with a 1AU radius. You make it as small as your energy collecting and support structure materials can handle when it comes to heat from the Sun. We ought to be able to build something that could survive closer to the Sun than Venus.
Then you hang pods off umbilicals around the equator to live in. Or hell, just orbit the thing and get your power by microwave beam.