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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[–] johsny@lemmy.world 112 points 5 months ago (1 children)

They only work during the day though.

[–] Adori@lemmy.world 6 points 4 months ago (1 children)

This is what they said about solar panels too, maybe it'll work out.

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[–] slazer2au@lemmy.world 62 points 5 months ago (1 children)
[–] Kyoyeou@slrpnk.net 5 points 5 months ago

Damn that looks cool

[–] Spacehooks@reddthat.com 43 points 5 months ago (4 children)

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

[–] rockerface@lemm.ee 21 points 5 months ago (1 children)

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

[–] Spacehooks@reddthat.com 8 points 5 months ago (2 children)

Well unless they are monitoring or are relatively close. The issue was they got annoyed cause their decedendants won't see their "holy constellation". Something like a north star to them I guess. So anyway I started a purification campaign In response.

[–] htrayl@lemmy.world 7 points 5 months ago* (last edited 5 months ago) (3 children)

...no, they won't know for a few hundred years due to the actual speed of light and vast distances of space.

[–] neatobuilds@lemmy.today 8 points 5 months ago

Unless they have some fancy alien sensor with quantum entangled particles so they get an alert instantly

[–] Spacehooks@reddthat.com 4 points 5 months ago

You're assuming they are not part of the deep state already!

[–] DragonTypeWyvern@midwest.social 2 points 4 months ago* (last edited 4 months ago)

It's a Stellaris reference. Once you can build Dyson spheres there's a chance your (also FTL capable) neighbors complain about you blocking their sacred star.

I usually just give them money and they forgive me.

[–] Famko@lemmy.world 2 points 4 months ago (1 children)

Just put them in the Synaptic Lathe and forget about them.

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[–] TheTechnician27@lemmy.world 13 points 5 months ago

"People of Earth, I am Lrrr of the planet Omicron Persei 8."

[–] 9bananas@lemmy.world 2 points 4 months ago

excellent stellaris reference! ;)

[–] original_reader@lemm.ee 24 points 5 months ago (3 children)

You need to watch more Star Trek, friend.

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

Thank me later. 😁

[–] OpticalMoose@discuss.tchncs.de 6 points 5 months ago

Classic episode; one of my favorite

[–] FlyingSquid@lemmy.world 3 points 5 months ago

With a bottle of green.

[–] BowtiesAreCool@lemmy.world 2 points 4 months ago

No bloody A B C or D

[–] batcheck@lemmy.world 14 points 4 months 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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[–] M137@lemmy.world 12 points 4 months 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 18 points 4 months ago

One of today's lucky 100000

[–] Kyoyeou@slrpnk.net 7 points 4 months 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 4 months 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

[–] frezik@midwest.social 3 points 4 months 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.

[–] MehBlah@lemmy.world 2 points 4 months ago

There was a star trek novel dealing with it. I read it but don't remember any details. My favorite along those lines was the ringworld books.

[–] VitoRobles@lemmy.today 3 points 4 months ago

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

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[–] rumba@lemmy.zip 9 points 4 months ago (1 children)
[–] VitoRobles@lemmy.today 6 points 4 months ago (1 children)

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

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[–] mipadaitu@lemmy.world 8 points 5 months ago (1 children)
[–] argh_another_username@lemmy.ca 5 points 5 months ago

Wait! The same problem Larry Niven’s Ringworld have also applies to Dyson Spheres? Huh! Saving to read later.

[–] Tuxman@sh.itjust.works 8 points 4 months ago (1 children)

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

Dyson Grids are the future!!! 😜

[–] ICastFist@programming.dev 3 points 4 months ago (1 children)

Or DYson Bubbles, which would also "cover" enough "surface" to be viable without needing god knows how many planets' worth of material

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[–] LordeMostarda@lemmy.eco.br 6 points 4 months ago (1 children)

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

[–] Lemminary@lemmy.world 2 points 4 months ago

Ok this one's new to me!

[–] Internetexplorer@lemmy.world 5 points 4 months ago

Kind of looks like an atom

[–] lipilee@feddit.nl 5 points 4 months ago

Okay but where does the invisible hand dryer go?

[–] m0darn@lemmy.ca 4 points 4 months ago (5 children)

Is dark matter just Dyson sphered stars?

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

My initial reaction: "What? No."

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

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[–] Quadhammer@lemmy.world 4 points 4 months ago

Start with a dyson ring or swarm

We will be lucky to have Dyson vacuums at the end of this century

[–] bss03 2 points 4 months ago

You might like this video: https://www.youtube.com/watch?v=pP44EPBMb8A about how to build one from Earth.

[–] merdaverse@lemmy.world 2 points 4 months ago (5 children)

It's a pretty cool concept, and I enjoyed building one in Dyson Sphere Program, but I don't really understand how you would transport that amount of energy to where you need it. Are they like mirrors that redirect and focus light to some point?

[–] Geobloke@lemm.ee 2 points 4 months ago

I guess you would store it in chemicals like oil or create radioactive substances that are optimised for specific energy decay rates

[–] Hadriscus@lemm.ee 2 points 4 months ago

Split into several laser beams targeting a bunch of big-ass converters in line around the equator. But it would have to be extremely accurate and route a fraction of total power unless you want to pulverize earth

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