this post was submitted on 17 Feb 2025
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Today I Learned

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A Dyson sphere is a hypothetical megastructure that encompasses a star and captures a large percentage of its power output. The concept is a thought experiment that attempts to imagine how a spacefaring civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone. Because only a tiny fraction of a star's energy emissions reaches the surface of any orbiting planet, building structures encircling a star would enable a civilization to harvest far more energy.

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[–] endeavor@sopuli.xyz 5 points 2 days ago (1 children)

Maybe make it a dyson fan since the sphere would only work during the daytime. In polar areas that means half a year without any energy production!

Whereas there is always solar wind.

[–] BigBrainBrett2517@lemmy.world 2 points 2 days ago

wHaT aBoUt wHen iTs NoT WinDy!!??!?!?

[–] johsny@lemmy.world 117 points 4 days ago (3 children)

They only work during the day though.

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[–] rumba@lemmy.zip 9 points 3 days ago (1 children)
[–] VitoRobles@lemmy.today 6 points 2 days ago (1 children)

That's crazy that they made this hypothesis based on a steam game

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[–] M137@lemmy.world 12 points 3 days ago (2 children)

Some TIL posts really surprise you, it's crazy to me that you have never heard about this. Not being degrading or anything like that, it's just surprising.

[–] Ellvix@lemmy.world 21 points 3 days ago (1 children)
[–] rowanthorpe@lemmy.ml 2 points 2 days ago

That's definitely one of Randall's more wholesome ones. By the way, this is one of my favourite book quotes on that subject:

The best thing for being sad," replied Merlin, beginning to puff and blow, "is to learn something. That's the only thing that never fails. You may grow old and trembling in your anatomies, you may lie awake at night listening to the disorder of your veins, you may miss your only love, you may see the world about you devastated by evil lunatics, or know your honour trampled in the sewers of baser minds. There is only one thing for it then — to learn. Learn why the world wags and what wags it. That is the only thing which the mind can never exhaust, never alienate, never be tortured by, never fear or distrust, and never dream of regretting. Learning is the only thing for you. Look what a lot of things there are to learn.

T.H. White, The Once and Future King

[–] Kyoyeou@slrpnk.net 7 points 3 days ago (4 children)

Yeah never heard about it, although I never watched Star Trek personally.

But did you know that we can extract Graphene by heating it up super high so that everything else gets destroyed except graphene?

[–] Madison420@lemmy.world 4 points 2 days ago

Read the bobiverse and you'll come across a topopolis. The pictures on wiki suck so here's one from fiction.

https://kardashev.fandom.com/wiki/Topopolis

[–] VitoRobles@lemmy.today 3 points 2 days ago

I didn't know that! You keep sharing the hits! Keep it coming!

[–] frezik@midwest.social 3 points 3 days ago (1 children)

Eh, there's only one in all of Star Trek, and they forgot about it after one episode. Should have a whole series.

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[–] m0darn@lemmy.ca 4 points 2 days ago (3 children)

Is dark matter just Dyson sphered stars?

[–] cewren@lemmy.world 1 points 12 hours ago (1 children)

While the idea is charming, a Dyson sphere itself would still consist of matter and as such it would emit radiation according to its temperature (https://en.m.wikipedia.org/wiki/Thermal_radiation). And since it surrounds a star it is heated from the inside and would definitely emit radiation that can be detected. Dark Matter is missing this radiation part and is only observed by its gravitation.

So the answer is no, unfortunately.

[–] m0darn@lemmy.ca 1 points 1 hour ago (1 children)

It would definitely emit thermal radiation. if it was 99% efficient and the size of pluto's orbit, around a start like the sun, and the energy was used to create matter, I think it would radiate 0.009 W/m2 with a peak emission wavelength of 150micrometers. The James Webb telescope has infrared capabilities that max out at 28.5 micrometers so def not detectable.

But probably a dyson sphere would be smaller than pluto's orbit, which would greatly increase the apparent power, and shorten the wavelength. idk it's all imaginary.

I won't subject you to my hand writing but I did (power of sun × 0.01)/(surface area of sphere with Pluto's orbital radius) to get radiation intensity (0.009 W/m2). Then rearranged Stefan-Boltzmann law to solve for temperature (19.8K). Then used Wien's Displacement Law to calculate the peak wavelength (1.5×10^-4^ m).

Maybe I'll run the numbers again with a martian orbit radius, and 50% efficiency.

[–] m0darn@lemmy.ca 1 points 1 hour ago

Okay I did the same calculation but with Martian orbit as dyson sphere size, and 50% efficiency I got a wavelength of 3.4um so nicely in the infrared range of JWST.

I think the sphere would need to be like 99.95% efficient to be undetectable by JWST at Martian orbit radius.

[–] spicehoarder@lemm.ee 4 points 2 days ago* (last edited 2 days ago) (1 children)

My initial reaction: "What? No."

After thinking a little bit: "hmm I guess you could say that..."

[–] m0darn@lemmy.ca 1 points 1 day ago* (last edited 1 day ago)

Like I'm sure it's not but I don't know if it's a worse explanation than any of the other ideas being considered. But I don't know enough to even know how wrong I am.

[–] Quadhammer@lemmy.world 4 points 2 days ago

Start with a dyson ring or swarm

[–] slazer2au@lemmy.world 66 points 4 days ago (3 children)
[–] umbrella@lemmy.ml 8 points 3 days ago (3 children)

this looks like it will suck 500 hours out of my life the moment i press play

[–] 9bananas@lemmy.world 2 points 2 days ago (1 children)

it's basically factorio, but it allows 3D belt placement and interplanetary/interstellar transports!

it's excellent!

[–] umbrella@lemmy.ml 1 points 2 days ago* (last edited 2 days ago) (1 children)

factorio latest update added interplanetary stuff! its actually quite cool.

please send help!

[–] 9bananas@lemmy.world 2 points 2 days ago (1 children)

oh yeah, i know!

but there's like 5 planets in factorio...there's upwards of 16 entire solar systems in DSP ;)

[–] umbrella@lemmy.ml 1 points 2 days ago

please don't tempt me

[–] dependencyinjection@discuss.tchncs.de 6 points 3 days ago (1 children)
[–] umbrella@lemmy.ml 3 points 2 days ago* (last edited 2 days ago)

i cant. tell me if you find a way to escape. please.

[–] frezik@midwest.social 4 points 3 days ago

That's correct.

[–] murmelade@lemmy.ml 23 points 4 days ago (5 children)

I pirated this to check it out and enjoyed it so much that I bought it even though it's in Early Access and that's very very rare for me. I still haven't played it more though as I'm still waiting for it to come out of EA, looking very much forward to play it again.

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[–] Internetexplorer@lemmy.world 3 points 2 days ago

Kind of looks like an atom

[–] Spacehooks@reddthat.com 44 points 4 days ago (4 children)

Be carful with those. You may block the light of constellation aliens use and really piss then off.

[–] 9bananas@lemmy.world 2 points 2 days ago

excellent stellaris reference! ;)

[–] rockerface@lemm.ee 24 points 4 days ago (7 children)

Eh, they won't find out until a few centuries later anyway

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[–] Tuxman@sh.itjust.works 8 points 3 days ago (11 children)

I don’t remember the math, but you lose return on investment after a certain percentage of coverage.

Dyson Grids are the future!!! 😜

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[–] LordeMostarda@lemmy.eco.br 6 points 3 days ago (1 children)

There is also the Matrioshka brain, a hypothetical supercomputer powered by a Dyson sphere

[–] Lemminary@lemmy.world 2 points 2 days ago

Ok this one's new to me!

[–] halykthered@lemmy.ml 23 points 4 days ago (4 children)

A pinnacle of science, a wonder of engineering, that we will never get to see in our lifetimes. Instead, we get to see Taiwan get nuked or something, I don't know. I don't follow the news much, I only know I'm disappointed.

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[–] original_reader@lemm.ee 26 points 4 days ago (3 children)

You need to watch more Star Trek, friend.

Specifically "The Next Generation", Season 6, Episode 4, " Relics".

Thank me later. 😁

[–] BowtiesAreCool@lemmy.world 2 points 2 days ago

No bloody A B C or D

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[–] batcheck@lemmy.world 14 points 4 days ago (1 children)

Came here to say that if you like this concept, Peter Hamilton has a book series called Commonwealth Saga in the science fiction category that is excellent. Lots of pseudoscience from early 2000s in that series.

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