The best evidence for extraterrestrials may be their massive engineering projects

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The best evidence for extraterrestrials

I found it!



Nah. Creating a Dyson Sphere requires matter-transformation and anti-gravity technology that’s so far beyond the realms of real science – even, yes, the science we don’t have – that they’re pretty much fantasy at this point. Better reasons for not hearing from ET’s include:

– Self-destruction as a function of Technology (Nukes, climate change, etc)
– Metal-poor planets (Can’t build a radio without metal …)
– Inability to see/understand other planets (Somewhere, there’s a race of lobster-people who are smart, but don’t see the sun and can’t make a fire; they write great poetry, but that’s about it.)
– Colossal indifference
– Deliberate Shunning

Niven observed, rightly, you’d need matter-transformation and superstrong materials for just a ringworld; a Dyson Sphere would be even tougher.


In the end, until we have met at least one extraterrestrial civilisation, there is simply nothing science can say on the matter. You can’t extrapolate anything from a sample size of one. Would ETs be sending enormously powerful radio signals / building Dyson spheres / visiting other stars? We cannot do better than guess.

The Dyson sphere idea is even more tenuous than SETI, both because it requires a much longer chain of assumptions to explain why they’d exist, and because even if you found a hundred “Dyson spheres”, there would be no justification for assuming that’s what they actually were. At least if SETI does find the kind of signal they’re looking for, it will likely be unambiguous.


I concede all your points, and really hope it’s indifference because that would be hilarious, however there’s one key thing missing. You don’t know what you don’t know. You might think you know, but… you don’t.

I’m a huge fan of Larry Niven, and the Ringworld series, however he’s one guy.


Obligatory SMBC:




Massive engineering projects like… THE GREAT PYRAMID OF GIZA?!


Agree. As much as I’d love these fantastic megastructures to exist somewhere, to wait for evidence of a civilization that can engineer things at the scale of a solar system is about as likely as waiting for them to drop by for a visit. If either is possible at all, it’s by means we cannot imagine. Sure, there’s no hard limit like the speed of light constraining the construction of megastructures, but that’s the only thing that makes it seem superficially more plausible.

Is it even necessary to enclose enough of the star to see from light years away to get a massive power surplus? I don’t feel like trying to do math, but I’d bet a ring of orbiting collectors inside the orbit of Mercury and not even visible from the Earth could generate more power than we could practically use.

Furthermore, is it even a good idea? You think we’ve got climate problems now, imagine what happens if we’re funneling the entire output of the Sun onto the Earth and using that power for… something, god knows what. It’d be like a magnifying glass on an anthill. If our first megastructure is a Dyson Sphere, our second has to be an unimaginably massive heat sink, which is probably a harder engineering problem than the sphere was in the first place.


too much work looking all over the universe - If they’re lizardoids - they probably have a facebook page anyway


The Pyramids are puny engineering projects, mere Lego blocks in the desert.

Now, the Hollow Moon – that’s a massive engineering project.


Also, if they’re smart, they may realize that it’s the sort of thing beings like us could look for. And maybe they don’t want company, so they could also build a Dyson Sphere and surround it with a lot of dust clouds so it’s not visible.

Or, they could have a lot of really lovely planets that they can hop around on that have nice windmills, solar power plants, fusions plants with low heat signatures. Maybe space elevators and ladders to travel around on. But to throw off any would be tourists, they figure out interstellar travel, and build Dyson Spheres with HUUUGE heat signatures light centuries away from where they live, just so other potential civilizations aim their exploratory space ships at the likely targets of “potential space engineering”. Meanwhile, they hang out in their charming corner of the galaxy, stay quiet and enjoy the lack of tourists.


There’s also the problem of how to find enough energy to escape your home planet’s gravity well en masse. Sure, we can do it for 7 astronauts in a tin can. But for massive off-world engineering projects, you’re going to need orders of magnitude more energy to bootstrap the work. And that energy source had better not cook the planet in the process. So no fossil fuels, and no other energy source available at the surface scales. Conclusion: no civilization (including us) can ever leave its homeworld.

ETA some calculations:


When people hear “Dyson Sphere” they tend to think of a single solid sphere. The original description is more of a “Dyson Cloud” or “Dyson Swarm”. You take an asteroid and build a habitat inside it, stick out some solar panels for power. Repeat until you run out of asteroids. Your asteroid is getting blocked by other people’s asteroids. You move into another orbit to catch more sunlight. Eventually, you have a very diffuse sphere around the star. Your population grows. You take apart some small moons to make more asteroids. Eventually, you take apart some planets. The cloud of asteroids around your star becomes more and more dense. If your civilization lasts, you build enough habitats orbiting around your star that they catch all the light and your star cannot be seen from the outside except for the waste heat coming out of your habitats dark side. That is a Dyson Sphere, not a solid shell. No matter transformation needed. No tech super advanced from what we could have in the next 100 years. If your civilization lasts 10,000 years and you don’t leave the system, very likely to happen.


Potential indicator of an active (or was at the time the light left the area) Kardashev type 3 civilization? Probably not, but hey, the possibilities are there!


and that’s why they’re called force fields.


We don’t hear from extra-terrestrials because they are at or below the same level of technology as us. Why do we keep working from this sci-fi stereotype of super advanced aliens? I’m sure most life on other planets remains non-self-aware creatures like most of Earth still is-- plants, animals, fungi, single-celled stuff.

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The most irrefutable proof of ET tech is that our nearly 6000 yottagram planet, which would clearly be most comfortable in a spheroidal shape, is somehow being forced into a pancake shape without the astronomical amount of constant energy input required to do so vaporizing everything around us.


Will Dyson or his heirs be able to sue the ETs for theft of intellectual property when or if said alien Dyson spheres are found?