Well obviously some highly advanced civilisation blew themselves up in the hugest possible way.
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The astronomy gets way easier if you just wait for the Berzerker probes. Those puppies bring the sufficiently advanced engineering right to you unless you hide well enough.
Yes, they don’t leave you much time to write up and publish; but observation is much simpler up close.
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Peter F Hamilton fans will know that if we do ever observe a Dyson Sphere we leave it the hell alone.
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That’s a fun calculation to do. If we estimate that the area of of sphere of radius 1AU is 2.811 e23 m^2, with the incident solar energy around 500 W m^2. I’ll leave Stefan-Boltzmann fans the job of finishing off the problem.
Are we really capable of recognizing massive engineering projects from all the other weird shit out there?
Keep back, it’s going to hurl!
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A Dyson Sphere is “an unlimited number of self contained colonies”. They are just spread out into a cloud around the system’s star to capture light. The most efficient arrangement would be a sphere. It is not one structure. It is not even planned. It just develops over time. You can use another power source other than sunlight for your colonies, such as fusion power, but sunlight is free and you might as well use that too. The colonies might start out in the plane of the eliptic (parallel to the sun’s equator) because that is where the raw material is, but eventually the self contained colonies will arrange themselves into a spherical grouping around the star because light (free energy) is escaping from the system above and below the plane of the eliptic.
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This, exactly. In fact the most likely arrangement is not a Dyson sphere but a Dyson swarm. Avoids the nasty orbital mechanics of trying to stabilize anything approaching a solid sphere. I am old enough to remember the “The Ringworld is not stable!” debates when Niven’s book came out. A sphere would be much worse.
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I suspect the first and most noticeable evidence of extraterrestrials will be the ones where their massive engineering projects failed spectacularly.
Extraterrestrials prove their existence by going non-existent.
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Consider a disc segment of a complete Dyson sphere at 1 AU. This will intercept the same radiation from the sun as the earth. It will re-radiate half that outwards, and half that inwards. The half that goes inwards will most likely strike the sphere again. So, the disc is getting 3/2 of what the earth does, and re-radiates 1/2.
The average albedo of the Earth is about 30%. So if the outside of the Dyson sphere was painted matt black, it could re-radiate 3x as much as the Earth does (just). No hard sums or physics needed.
I think Dyson spheres are still a silly idea. Do we rate civilizations by how much power they consume? But the physics is good.
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Ants are not aware of our great megastructures. Buildings, etc.
If alien megastructures exist, we have probably been looking right at them all our lives, without knowing they are artificial.
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In astronomy, below the streetlight is the only place you can look. You make do with what you have.
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Dyson spheres are more of a ‘thought experiment’ on the hard limits of energy consumption.
They are so impractical to actually build my guess would be that they’re impossible.
Seems to me that the conditions for life to thrive are not common. But even on an ideal place like earth where it does thrive, we humans are almost a fluke. We’re the only species out of billions of successfully thriving life forms that can create any sort of complex technology. And even that was not inevitable. It took millions of years of intelligent humans (and probably intelligent human-like relatives in the distant past) who never so much as developed a combustion engine before our collective knowledge really started to do cool stuff. And most of us would be living like people in the Middle Ages still if all the technology was taken away today because individually most of us don’t understand any of that technology. I’m not saying we’re alone… who knows of course. But it seems to me that we’re a pretty rare fluke and I don’t have my hopes up. I think it’s a lot more likely that we’re gonna find evidence of some alien bacteria like species of the sort that survives in harsh conditions on earth than some giant super technology producing beings.
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remember that status quo album cover…
guy dives into sea… submarine launches trident missile
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That’s not really a compelling argument for me. Alien megastructures are so huge and advanced that we can’t detect them as being structures at all feels like the SETI version of God is so powerful that He’s invisible all the time, and any random thing that happens in life can be taken as proof of His power.
Either statement could end up being objectively correct, but you have to have faith that they’re correct.
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If your civilization lasts 10,000 years. Hasn’t happened yet. Odds aren’t good that it ever will.
Ants are certainly aware* of my megastructure, because they show up in the bathroom or the kitchen from time to time.
*for very small values of awareness
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Yeah but they don’t know it is the product of and Alien intelligence (from their perspective anyway).
Given how well water blocks radiation, we’ll never detect all those mоist superintelligent aliens.
