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# Dyson's Globe

It's pretty dark on the outside
 (+3, -4) [vote for, against]

You can construct this in two ways:

1) Construct a small model of the sun, and surround it with a thin shell, but leave a small gap that allows light from the sun to strike the orbital path of the Earth. If that doesn't coincide with the entire orbital path of the other planets, then they are SOL. That isn't terribly important, though, since this model isn't to scale and we are only concerned with the Earth in this context.

Mount a small model of the Earth outside the perimeter of the Dyson shell, aligned with the gap. None of this is to scale, so add a couple of dish antennas to the Sphere and the Earth to indicate that the Sphere is gathering and providing a stunning amount of energy to the Earth via microwave transmission. Even out of scale, it's obvious that the interior of the sphere can intercept tremendously more energy than the Earth can by itself, and even if the entire sphere is no more efficient than a typical plant (a fraction of a percent efficient) at converting sunlight to energy, and transmission efficiency is similarly poor, there's still way more energy available than we currently use. Goodbye oil.

That's it.

2) Construct a small model of the sun. Construct a similarly small model of the Earth. These are not to scale. Mount them in relationship to each other, and now surround them with a model of a Dyson Sphere. This time the dish antenna on the Sphere is on the inside, again pointed toward Earth. Paint the Sphere's exterior a deep matte black. Do not leave a window for viewing.

That's not quite it. This requires a similar model, without the Dyson Sphere, for comparison purposes. It might be a good idea to have the sun be a light bulb, and the Sphere a non-insulating material, to tangibly suggest to viewers what a Sphere might look, or more practically, feel like in reality: slightly warm.

 — elhigh, Jul 17 2007

smaller Dyson smaller_20Dyson_27s_20sphere
Almost the same idea [the great unknown, Jul 18 2007]

So, forgive me for being blunt, you've described two models, but what's the actual point here?
 — zen_tom, Jul 17 2007

I'm going to make a model of a spoon, and a model of a raspberry. Neither of them will be to scale.
 — moomintroll, Jul 17 2007

my brain hurtz.
 — jhomrighaus, Jul 17 2007

Construct a small model of the halfbakery and post this there.
 — nuclear hobo, Jul 17 2007

Either way, it's a Dyson sphere, a solid shell of matter enclosing a star, which is the most popular and least probable conception of the Dyson shell. Dyson's original idea was simply that any advanced civilization will devise methods to capture all the energy from their star.
 — baconbrain, Jul 17 2007

 I've never understood

 Other:

 general - in particular. its always been - any old s**t...

explanations welcome.
 — po, Jul 17 2007

[moomintroll], there is no spoon.
 — normzone, Jul 17 2007

 There is easily enough solar energy hitting the Earth to power everything on it, and then some. It is somewhat easier to cover 10% of the surface of the Earth with solar panels than to encase a star. Why surround the whole star anyway, why not just start giving Earth rings like Saturn's made of solar panels?

Would anyone care to calculate the amount of energy you could epect from a 1m wide solar panel surrounding the Earth at, for example geostationary orbit (not that it needs to be at that distance).
 — marklar, Jul 18 2007

I can see where you're going with this. We could have a hole on this globe so earth still gets sunlight. the inner surface of the shell can collect energy. It could also be 2 hemispheres that leaves a gap around the equator. that way the rotation will not have to match earth's orbit and still provide light to the other planets (If any are not use as material for this shell)
 — the great unknown, Jul 18 2007

Will the turtles be able to bear the extra weight?
 — AbsintheWithoutLeave, Jul 18 2007

How about making the shell with trillions of glass spheres filled with growing sugar cane and corn than we can harvest to make ethanol to power our SUVs?
 — Galbinus_Caeli, Jul 18 2007

 The turtles will be provided with Dyson Sphocks to support their ankles.

 I know there's enough energy striking the Earth's surface to power everything, but that's small thinking. I want to be able microwave the whole damned planet if the mood strikes me.

[marklar], you can expect solar panel output to jump by about 30% in orbit compared to what it gets on the ground. Unless it's in the earth's shadow. Then the output gets pretty low.
 — elhigh, Jul 20 2007

 It always feels good when someone else selflessly promotes your idea. There´s no shame in it. It´s shameless. Shameless else promotion. Cheers [bigsleep].

Nice Dyson gag by the way. It´s dirty work, but somebody´s gotta do it.
 — theleopard, Jul 21 2007

 [marklar] - //calculate the amount of energy... from a 1 m wide solar panel at... geostationary orbit//

circumference: 264,924 km
apparent length as viewed from the sun: 168,656 km
length of occulted segment: 12,756 km (earth's diameter)
useable length: 155,900 km
useable area: 155,900,000 m^2
solar constant: 1366 W/m^2
impinging solar energy: 212,959,000,000 Watts
multiply 213 gigawatts by efficiency percentages for your favorite PV cells and preferred method of energy downlink.
 — lurch, Jul 21 2007

This idea is already semi-baked (Type II civilizations can consume the entire power output of a star). However, this particular way of consuming solar energy is somewhat impossible to implement given that most materials would melt and vaporize from the immense heat of the sun, plasma at 10^6-10^7 K is hot enough for fusion to occur.
 — quantum_flux, Jul 22 2007

QF, if the diameter of this Dyson is the same size as Murcury's orbit, the harder materials, like those on that planet, shouldn't melt. The energy collected would be the same as a 1 AU sphere. Also since it will be smaller, it would need less materials to make one even if it has a thicker shell.
 — the great unknown, Jul 23 2007

 I was going to show that the sphere would need to be something like 1 gram per square per kilometre, but unless my calculations are wrong by a factor of big it could actually be 440,000kg/m^2 just using Jupiter. (Assuming Jupiter=1900x10^24kg, sphere radius=58.6x10^9m)

Hmm, now if we could just tie a rope around Jupiter ...
 — marklar, Jul 23 2007

Tying a rope around Jupiter isn't the problem, it's finding a way to roll it out flat.
 — elhigh, Jul 23 2007

though i'm pretty sure that absinth is the only one who sees the larger picture, i will address bigsleep's point 2. i've always thought that it is more important to be able to make jokes about the big ideas than it is to merely have the big ideas. but it's better to have (and share) the big ideas than it is to not have (or not share, which amounts to the same thing) them. so i say +. specifically for the "what a Sphere might look, or more practically, feel like in reality: slightly warm."
 — spike, Oct 15 2007