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submitted 6 months ago by ooli@lemmy.world to c/space@lemmy.world
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[-] Track_Shovel@slrpnk.net 62 points 6 months ago

Got mine plugged in: gonna vacuum later

[-] Steam-Roller@kbin.social 6 points 6 months ago

Ha ha yup me too! Got one hiding in my closet. $50 and it’s theirs 🤣

[-] Zorque@kbin.social 7 points 6 months ago

Isn't that like a 95% loss?

[-] Steam-Roller@kbin.social 5 points 6 months ago

From MSRP, yes. Mine was second hand and has seen better days. One of the older DC07 ones

[-] Tylerdurdon@lemmy.world 48 points 6 months ago

Okay, so the title is a bit off. They're hunting for partial Dyson spheres using infrared and optical.

I was confused on how they would detect something completely blocking a sun from millions of light-years away.

[-] GreyEyedGhost@lemmy.ca 30 points 6 months ago

Even a Dyson sphere, which is technically unlikely anyway, would be possible to spot. You would look for something very bright in the infrared spectrum with almost no light in the visible spectrum. It would also be larger than a normal star of the same energy, but that would be hard to tell given all the other issues.

A partial swarm is easier because it will have variability towards more infrared and then back to a more normal spectrum.

And, of course, all this is speculation until we find a candidate and determine it doesn't have a natural source for that behavior.

[-] FooBarrington@lemmy.world 6 points 6 months ago

Why would there necessarily be strong infrared emissions? Since a Dyson Sphere is meant to harvest all energy produced by a star, any leakage would be unnecessary inefficiency, wouldn't it?

[-] GreyEyedGhost@lemmy.ca 10 points 6 months ago

Thermodynamics says that energy can't be destroyed (mass-energy, but generally that won't matter). So after the work of running your stellar civilization is done, you will radiate out waste heat. There is no real way around this without breaking thermodynamics or having a handy black hole to dump all your waste heat into. Therefore, the energy of the star will still be released, but it will be released as infrared.

[-] FooBarrington@lemmy.world 4 points 6 months ago

If you're using the Dyson sphere purely as a power plant and e.g. charge batteries, the thermal radiation will be distributed over the whole area covered by the civilization.

A solar panel, or any other power generator we use, doesn't radiate away all the generated energy either. It's radiated from the point of use.

[-] GreyEyedGhost@lemmy.ca 4 points 6 months ago

So you heat habitats, which radiate heat. And run computers, which radiate heat. And move objects around, which radiates heat (among other things). And if you merely absorb energy from your star...it radiates as heat. This is the whole idea of entropy. Unless your lasers are particularly efficient and you use them to beam the energy elsewhere, your Dyson swarm is going to radiate heat equivalent to the energy your star puts out.

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[-] Passerby6497@lemmy.world 3 points 6 months ago

Because all that energy contains heat as well, and you'll need to balance the heat from your star along with the energy absorbed.

You're never going to get to 100% efficient conversion, so you'll have to radiate away the heat so your sphere doesn't melt or something.

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[-] ShittyBeatlesFCPres@lemmy.world 17 points 6 months ago* (last edited 6 months ago)

Dyson swarms are more likely. We even have a tiny one with our satellites using solar power in a heliocentric orbit. (Dyson spheres are basically impossible.) But we could theoretically detect either in infrared since if it doesn’t give off waste heat, it’d all heat up and melt.

That being said, I’m personally of the opinion this is a waste of time. Not to get all Fermi Paradox but it’s pretty sci fi brained to think any other species out there is as dumb as we are. Space sucks. You die super fast there. Everything had to align just right for Earth to make a bunch of dumb fuck apes willing to strap themselves onto rockets, have a planet small enough that the rocket could even overcome gravity to enter orbit using chemical rockets, and a World War and Cold War to accelerate things.

[-] LordGimp@lemm.ee 8 points 6 months ago

Time will always be the great filter. Even if we did spot a Dyson swarm, we have no feasible way to contact anything on a practice timescale. Any speck of civilization we detect will be hundreds of thousands of years out of date at best, billions at worst. Life in the universe, imo, is basically guaranteed. If it happened once, it can happen again. Meaningful contact between separately evolved concurrent sapient species? Not likely.

[-] echodot@feddit.uk 3 points 6 months ago* (last edited 6 months ago)

Everything had to align just right for Earth to make a bunch of dumb fuck apes willing to strap themselves onto rockets, have a planet small enough that the rocket could even overcome gravity to enter orbit using chemical rockets, and a World War and Cold War to accelerate things.

Given the estimated number of planets in this galaxy alone, it's particularly guaranteed that very similar events have occurred on multiple worlds. Unless you're proposing that all theoretical alien races are Vulcan level logical then tensions and interstate conflicts will always exist that will advance technology. This is practically an inevitability unless the race question is a hive mind species.

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[-] echodot@feddit.uk 3 points 6 months ago* (last edited 6 months ago)

If it was actually completely enclosing a star that would be impressive. It would also be a bit pointless, since It would result in your spear heating up to stupid temperatures, Which would cause it to glow in the infrared, so you would detect it by that infrared.

[-] Simulation6@sopuli.xyz 3 points 6 months ago

Isn’t the idea that the sphere would have a circumference the size of earths orbit? Not sure it would heat up all that much to be noticeable.

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[-] uriel238@lemmy.blahaj.zone 33 points 6 months ago

This feels like trying to determine FTL travel is possible by looking for warp signatures. We don't yet know megastructures are feasable.

[-] AA5B@lemmy.world 19 points 6 months ago

Agree this sounds ridiculous, but isn’t this the basic point of science? Propose something is possible, then make predictions and see if you can prove or disprove. The Dyson Sphere idea itself is ridiculous, but to the extent you can detect large scale technology around a star, that would be fantastic. Even better, this is simply a query on existing data. Imagine if they detected intelligent life this way!

Kind of reminds me of the search for Dark Matter. That whole idea sounds so preposterous yet is the best fit for our current knowledge. But we can make predictions based on this. What could all this matter be to fit the theory while remaining undetected so far? Then you can build particle detectors to find them and particle accelerators to explore conditions for causing them. Eventually we should be able to either detect that matter or to rule out enough possibilities for another theory to better fit our knowledge

[-] echodot@feddit.uk 8 points 6 months ago

We don't really know that building a long-term colony on the Moon or Mars is feasible. We assume that it is because there's no obvious reason that it isn't possible other than it being difficult, but that's just a matter of working up to the necessary technology level.

There's nothing inherently problematic in the idea, it's just very big and ambitious. Equally we have no reason to believe that mega structures are not possible, you throw enough resources and science at the problem. FTL on the other hand has real physical restrictions against its existence, we have no reason to believe those restrictions can be overcome.

Dyson spheres are just very very big, no new crazy negative energy, subspace conduits required, just brute force engineering.

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[-] neo@feddit.de 5 points 6 months ago

In the Kardashev Scale, a Type II Civilization would build a Dyson Sphere

I know there's an methodical thought process behind those things, but mhh... this feels more fiction than science to me.

I'm fine with research, but I'm worried some might use it as a slippery slope into pseudo science.

[-] echodot@feddit.uk 4 points 6 months ago

I don't think there's any real risk of that. The media often like to overhype scientific inquiries but all they're doing is looking at existing data

[-] Gimpydude@lemmynsfw.com 17 points 6 months ago

A Ringworld would be more likely than a Dyson sphere, the mass requirements are so much lower.

[-] Hegar@kbin.social 7 points 6 months ago

Wouldn't a Dyson swarm be much easier to construct than either? Like a dyson sphere but a swarm of smaller collectors.

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[-] Telodzrum@lemmy.world 4 points 6 months ago

RTFA they are looking for swarms, rings, and other subtypes of Dyson Spheres.

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[-] teft@lemmy.world 4 points 6 months ago

Ringworlds are not orbitally stable so they are firmly in the realm of sci fi.

[-] echodot@feddit.uk 4 points 6 months ago

Neither are Dyson spears

[-] argh_another_username@lemmy.ca 4 points 6 months ago
[-] Maestro@fedia.io 5 points 6 months ago
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[-] Crumbgrabber@lemm.ee 13 points 6 months ago

As an owner of three private for profit Dyson spheres, I strongly disapprove.

[-] blazeknave@lemmy.world 4 points 6 months ago

Stellaris users in the wild

[-] nyctre@lemmy.world 9 points 6 months ago

Let's say we detect one in some other galaxy. What then? And how do you reach out to them?

[-] Martineski@lemmy.dbzer0.com 15 points 6 months ago

We don't because we can't. We will just observe the thing for science and stuff.

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[-] Demuniac@lemmy.world 6 points 6 months ago

Well if we find one we have proof of advanced life elsewhere in the universe. That's the most important thing. Reaching out will take millions of years.

[-] tsonfeir@lemm.ee 5 points 6 months ago

Does it roll around and suck up dirt? How does this work?

[-] postmateDumbass@lemmy.world 5 points 6 months ago

No. So it works just like the vaccuum cleaner.

[-] barsquid@lemmy.world 2 points 6 months ago

Kind of, except it is more like wrapped around a star and sucks up light.

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this post was submitted on 11 May 2024
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