What are Dyson spheres? What would be involved in building one? How much energy would it cost, and could we ever pay it back? I discuss these questions and more in today’s Ask a Spaceman!

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EPISODE TRANSCRIPTION (AUTO-GENERATED)

Look, I'm aware that I'm, uh uh Let's put it this way. A skeptically leaning kind of guy that's always been in my nature. When I hear something, I rarely instantly believe it, and I usually start asking questions. As with all personality traits, sometimes this is a benefit like when I'm right to be skeptical and I don't buy a lie. And sometimes it's not so beneficial. Like when I should have just believed someone from the start. And I'm also aware that sometimes this skepticism can be viewed as pessimism or cynicism. So I want to be very careful in how I were the main point that I'm going to make in this episode. I want to be absolutely 100% clear that it is certainly possible to build a Dyson sphere. And for those of you who don't know what a Dyson sphere is, don't worry. We're gonna get to that. But I also want to be absolutely 100% clear that it's really stinking hard to do it so hard that I don't imagine us doing it any time soon, where soon can mean 100 years, 1000 years in a year or even 10,000 years, and it may be so hard to do it that it's not even a good idea.

And therefore, outside of some massive expression of artistic sensibilities, we may never build a Dyson sphere, and nobody in the universe may build a Dyson sphere. But still it's possible. And I must admit that we, as a species, have been capable of some truly awesome accomplishments. Uh, the things that our ancestors once thought were too difficult to actually do, like, I don't know, harnessing the power of the atom or curing diseases or, uh, or wiping out entire species. We we we're not so proud of that last one. But let's back up a bit. What the heck is the Dyson sphere and why is it so hard to build? The year is 1960. It's a groovy time. SETI. The search for extraterrestrial intelligence is just getting started, and it's mostly focused on radio signals. We had just invented this technology within the past few decades that could transmit signs of our intelligence far out into space. We're using radio to communicate back and forth, but those signals also propagate out into space and that those carry a sign of our intelligence.

So it wasn't unreasonable to assume that other intelligent species living in the same universe with the same set of physics would also discover radio and also blast out signs of their intelligence into the universe. It's also reasonable to assume that if other intelligent critters are out there, then at least some of them have been around for longer than we have, at least in a technological sense, in in terms of having radio, you know, early human ancestors spent millions of years with just a fire in stone hand axes. So imagine a species out there that views radio with the same sense of deep time that we do fire. It's also reasonable to imagine that aliens might become even more advanced than us and do things that we would consider impossible, or at least extremely difficult. And so we should fold into the steady program, not just searches for technologies at our level, like radio but speculative technologies.

That could happen if we continue progressing at our current rate of technological development. You probably didn't hear the air quotes that I put around the word progressing, so I want you to take a mental bookmark of that word because we're going to come back to that later. One of the first people to make this argument that we should look for speculative technologies was famed physicist, mathematician and all around smarty pants. Freeman Dyson. Now I could do a whole episode on Dyson. In fact, you're more than welcome to ask who he was and what his contributions to physics and mathematics were. But he's most known in the public for this random, one off idea he had seriously. There was one paper, and he became absolutely famous for this one idea, even though he did a bunch of much more important work. But that's a different episode. He wrote a paper on the subject, and his paper is, well, it always amuses me to read science papers from even a few decades ago.

The title of this paper is search for artificial stellar sources of infrared radiation, and it's short and it's very Oh, how do I put this politely? Hand wavy. It's not exactly rigorous or comprehensive or well argued. It's about one page long contains no equations or citations, no real rigorous treatment of the topic, and it would never pass peer review today. But, man, the 19 sixties, there were a different time. So here's the gist of Dyson's argument, and given the brevity of his paper, it's almost his entire argument. Earth's population is increasing, We need more resources, and we need more living space. He even used the word Lehman's ROM, which what was an odd choice of words, even in 1960. And if you don't understand kids, ask your parents why. But we need more stuff. We need more resources, more space and especially more energy.

The energy needs of humanity are increasing the space needs. The resource needs of humanity are always increasing to solve all of this. I don't know, maybe we could contribute to patreon. Patreon dot com slash PM Sutter. You get early access to episodes, you get a free versions, you get direct access to me, and you can help solve all of humanity's problems. Not really. That last part is not true, but you should still go to patreon dot com slash PM Sutter. I truly do appreciate all of your contributions well. To solve all of this, the need for more energy, the need for more living space. What if we just disassembled Jupiter and reassembled it as a shell surrounding the sun? I mean, why not? This shell surrounding the sun would capture all the solar radiation pumping out into space, And it would give us tons of living room because we could live on the inside surface of this shell. And because our population is increasing and because our energy needs are increasing, we are going to do it someday.

We're going to need to do it someday. And if we're gonna do it, then advanced aliens have probably already done it. So we can search for those advanced aliens by looking for these kinds of spheres surrounding their stars. How would we actually look for this? Well, the giant shell surrounding a star which ended up being the name Dyson Sphere. He didn't name it that himself. He wasn't that egotistical. This giant show would capture all the Starlight pouring out of that star and converted into energy. But no conversion into energy is 100% efficient. It will leave behind some waste heat in the form of infrared radiation. So the inside surface of the shell captures all this sunlight. All this energy, you do useful things with it, and then the outer surface of the shell will glow. It will be warm in infrared radiation. So when we go looking for stars and instead of small, bright points of visible light, we instead see smoothed out fuzzy blobs of infrared. We might be looking at Dyson Spheres. This is another form of searching for extraterrestrial intelligence, way advanced intelligence, but that's still intelligence.

OK, that's not a bad idea on the surface, but I didn't intend to make that a fun. But there you are. But his paper actually has a few mistakes. He went to Jupiter. He wanted to build this shell out of Jupiter because it's by far the most massive planet in the solar system. So there's a lot of stuff on Jupiter great shell building material there, except for the fact that the vast majority of Jupiter is just hydrogen and helium, which isn't so great for building large, rigid structures that you can play around on. So his estimates of the size of the shell that you can make from Jupiter are way overestimated. Second, he assumed that his shell is useful for both collecting solar energy and providing a living space. His words are quote comfortably habitable, but his estimates have the shell around 2 to 3 m thick, which is that just strikes me as a little on the optimistic side. If I know that I'm living on the inside of a giant shell that reaches around the solar system, he put his shell at something like twice the orbital radius of the earth, this massive structure.

And I know this gigantic structure. The only thing separating me and cold, hard vacuum is a few meters of dirt. Hm. I know we're talking about advanced technologies, but still that makes me feel uncomfortable. His shell is too optimistic. Third, it turns out that solid shells around stars are insanely fragile and unstable. You have to keep everything in perfect gravitational balance. Otherwise, gravitational tidal forces just tear everything apart, and that will happen unless you keep your star in the exact center of the sphere of good luck with that. Plus, there's issues with differing rotation rates. Well, let's just say that shells don't really work. Instead, it's better to build individual panels or pieces of a shell and have them free flying around the star, something that's called the Dyson Swarm. That's not necessarily a deal breaker. You don't actually need to construct an entire shell. You just need to break it apart into pieces. But it's worth talking about. Lastly, he assumes that it's inevitable that our population will continue to increase and our energy needs will continue to grow and so forth, and therefore we will need to build a sphere.

But that last point, that last assumption I will get to at the end so that that's it. That's Tyson's argument. Let's take Jupiter. Let's break it apart. Let's turn it into a shell A couple meters thick, this shell is gonna have a radius twice the orbital distance of the earth around the sun. We will live on the inside of the shell. It will collect all the solar energy, and we have tons of energy to to live our lives. And, I don't know, browse social media. I don't know exactly what we would do with all that energy, but I suppose an advanced civilization would figure something out. So I decided to run some numbers. I want to see how feasible it would be to actually build a Dyson sphere. Could we actually pull it off? Because it's one thing to say, Yeah, there's all this bastard it into a shell. But how now I'm just a poor country astrophysicist, and I don't know much about fancy engineering. So in the calculations that I'm gonna present to you, I made a lot of assumptions. I don't know what kind of super advanced materials our descendants will be capable of designing.

Maybe they could make a shell this big just a few meters across, and it'll be fine. Maybe not. I can't tell you how to actually build a Dyson sphere. That's not my department. But I wanted to see if it was energetically possible to build the Dyson sphere. In other words, no matter how you build a Dyson sphere, you're gonna need energy to do it. And I'll get into the details of what where those energy requirements come from. You need energy to do it, and then eventually you get some energy back by capturing more Starlight than you normally do. But is it enough? How long does it take? How long would it take to recoup your energy investment? So the details I'm not gonna care about for this discussion. I'm gonna assume that our super advanced descendants far in the distant future, yeah, they can design crazy exotic materials and they actually have the capability to disassemble planets. But if you're gonna build a giant shell or a series of smaller panels orbiting around the sun, you're gonna have to, you know, build it and you can't just conjure it up out of thin air.

That means that in order to build our Dyson sphere swarm an Archos and Nicholas commune or whatever, we're going to have to use the solid bodies of the solar system. The rocky planets, the asteroids, the comets, the inner rocky cores of the gas giants, Hydrogen and helium may be great gasses, but they're out. They're useless here. There's lots of ice in the solar system. It's useless at the distances where you need to actually build the shell. It will just turn into water. So in order to construct our Dyson sphere, we need to use the rocky material of our solar system. I'm also gonna assume just to make my life easier. That dirt is relatively interchangeable. Yeah, a shovel full of earth soil is different than a shovel full of lunar regolith, which is different than a shovel full of the interior rocky core of Jupiter. But when we're talking planet scale reengineering, I'm assuming all of that is gonna average out and that dirt is dirt around the solar system and that you have all the little bits and pieces of I don't know, silica and titanium that you need.

I'll leave the engineering details to my friends in the other department. My point is, we're just gonna look at dirt. We're gonna look at Rocky Planets, Rocky substances in the solar system and that's it. That's all we can build our Dyson sphere from. I'm also going to assume that our descendants will be bound to the same laws of physics that we know and love today, especially when it comes to energy. If they want to rip apart a planet great, they're gonna have to put some sweat into it. They need to invest energy to do the job. If they want to move pieces of planets around to different orbits, they're going to need to invest energy to do the job in order to engage in mega engineering projects. they're going to have to incur an energy debt that they will then have to repay. Building a Dyson sphere is going to take a certain amount of energy and building a Dyson sphere is limited by the building materials available in the solar system. Yeah, once you build your shell or your swarm or your panels or whatever your dodecahedra you then go on to collect solar energy for eternity or billions of years, and you can repay that investment.

But how long that takes will determine if the whole Dyson program is feasible or not. If it takes you a billion years worth of energy to build the Dyson sphere, you're not gonna build the Dyson sphere. If it takes you a few days, you just might. Speaking of energy, that's the first of Dyson's arguments for why we'll eventually need a Dyson sphere. Right now, humanity consumes around five times 10 to the 20 jewels of energy every single year, five times 10 to the 20 jewels of energy every year. And that's been going up quite radically for some time. We use more and more energy every single year to give you a sense of scale however, of how much energy is available in the solar system. Our sun blasts out 10 to the 26 Jews of energy every single second. That's a million times more energy every second than all of humanity uses in a year.

So, yes, we use a lot of energy for our factories and our airplanes and our podcasts in our campfires. But that's 11 millionth of the energy that our sun outputs in a second. There is so much more untapped energy available in the solar system. I can't even describe it. And so this is the key idea behind Dyson Spheres. Most of the solar energy generated by the sun just flies off into the space. Totally useless is on its way to Alpha Centauri, the Andromeda Galaxy. We don't get to capture it. We don't get to use it. Only a tiny fraction of all the Starlight produced by the sun around one part in a billion actually strikes the surface of the earth. Even if we coated the entire surface of the earth in solar panels, bye by oceans by by farms, it's all solar panels all the time. Even if we coated it every square meter of the earth in solar panels. We would still only capture a billionth less than a billionth of the energy put out by the sun.

But that's a lot of energy right there. If we could capture every single photon that struck the surface of the Earth and convert it into energy perfectly efficiently, we could pay for an entire year's worth of energy in less than an hour. That's just the fraction of Starlight hitting the earth, which is a billionth of all the energy generated by the sun in total. Even if we coated the entire surface of the earth. Or if we did that, we could pay for all of our energy needs in one hour. Yeah, we'd have no oceans or whatever, but, hey, we'd have lots of cheap energy. But what if our energy needs go up? What if we need more and more energy as our civilization becomes more advanced? What if it takes a day to build up enough energy that we then use for a year? What if it takes a month? What if it takes six months? What if our energy needs become so massive that even coating the surface of the earth and solar panels wouldn't be enough.

This is Dyson's argument now. If the Earth were bigger, we would capture more sunlight. We there'd be more surface area facing the sun. We would intersect more of the Starlight. We would waste less of it, less of it. Less of it would go out into interstellar space, and more of it would strike the Earth and we could have more energy available to play with. And this is the central conceit of the Dyson sphere. The more surface area facing the sun equals the more energy you have equals, the more fun you have and the more surface area you have facing the sun, the more livable surface area you have as a side benefit. This show is brought to you by better health. One of my favorite things about doing ask a spaceman is how much I get to learn about my own field. It's either stuff that I forgot from graduate school or I'm learning brand new because it's simply not a part of my training and expertise, and getting to learn new things and learn about yourself is so powerful.

One way to do that is through Therapy. Therapy doesn't solve all your problems, but that's not the point. It solves some of your problems, and that makes it worthwhile. You get to continuously learn about yourself through my own therapy. I learn a lot about myself, my relationship with others, how the world works. It's pretty powerful. If you are thinking of starting therapy, give better help. A try. It's online. It's convenient, flexible, and it can be suited to your schedule. Discover your potential with better help. Visit better help dot com slash spaceman today and get 10% off your first month. That's better. Help EEP dot com slash spaceman. So we need more surface area facing the sun in order to meet our ever increasing energy demand. So let's re sculpt the earth. Let's tear it up and replace it with a giant shell or pieces of a shell designed specifically to capture as much solar energy as possible. One problem. The earth is kind of glued together, and this is our first energy cost.

The binding energy of the earth. If I want to rip apart the Earth and turn it into a series of panels, I have to rip it apart and that takes energy and we can calculate the amount of energy you need to do this. It's called the Binding Energy. Take one particle, one little clump of dirt. Fling it off into space of the escape velocity that took energy that took work that took jewels. OK, that's one bit. Now take another bit. Launch it in space. Take another bit. Launch it into space. Take another bit. Launch it into space. You need to add up all the energy. Now, as you go, it gets easier because with every bit of mass that you remove from the earth, the earth is a little bit lighter, so escape velocity is a little bit lower. It's a little bit easier to get out into space. So the amount of energy you need for each successive launch of disassembling the earth goes down. And then you just add all this together and you find that the energy cost to unbind The earth is around 2.5 times 10 to the 32 jewels.

That is a million trillion times larger than our current annual energy consumption. All the energy that humanity uses in a year multiply multiply that by a million trillion. And that is the energy you need to unbind the earth. So if we rearrange all this material into a sphere, we better hope that we can gain enough solar energy to make this worthwhile. I mean, I have no idea how long the actual process of unbinding will take. So far, we have launched various things to escape velocity. Somewhere around 1 to 200 tons of material we have launched off the earth. We have unbounded the earth by 200 tons. So good for us. We started the process. I have no idea. You know, this just the process itself, of reconfiguring the Earth could take millions of years. I'm not even talking about that. That's a whole separate episode. But what I'm saying is, if we had some crazy advanced technology that made launches very, very easy, this is how much energy it would take just to unbind the earth.

That doesn't even include rocket fuel. And if we reassemble it into a shell at the same orbit as the earth. So we're not moving anything around, and we say that shell has a thickness of one kilometer, which makes me feel a little bit more comfortable and we keep all the former earth pieces in the same orbit. Then we couldn't build an entire sphere. There isn't enough dirt to do it. There isn't enough mass to build an entire shell at the Earth orbit one kilometer thick. But we could build part of a shell and we'd be able to capture a stunning 0.0004% of all the solar energy, which doesn't sound like a lot, but it's more than we have now. Right now we have a billionth. And if our energy conversion is around 10% if we're able to turn 10% of the solar energy into useful energy, we're looking at an energy payback time of around 60,000 years. 60,000 years. Considering the time scale of human civilization, that's that's a long time.

But considering what super advanced civilizations might be capable of, that maybe doesn't sound so insane. I don't know. I'll let you judge the value of that 60,000 years if you unbound the earth, turned it into a bunch of panels and then captured sunlight at this orbit. It would take you 60,000 years to get your money back in terms of energy. Now you would get a lot of surface area. You'd get the equivalent of 2000 surfaces of the earth. That's 2000 times more land 2000 times more sea, assuming you can find enough water, 2000 times more recreational facilities and so on. Plenty of room for everyone. But maybe we could do better. Maybe we could take these panels, these these pieces of the reassembled earth and move them closer to the sun, moving them closer to the sun blocks, more sunlight. You get to cover a greater fraction of the sphere surrounding the sun so that your energy capture rate goes up. But this is the second source of energy cost moving.

It takes energy. The thing is, the earth isn't standing still. It's orbiting the sun at tens of thousands of MPH. If you want to put it in a different orbit, you have to put work into it, and it doesn't matter if you're doing it one particle at a time or one planet at a time. You're gonna have to put the energy in, and there's actually two places where you need to put the energy in first, you need to decelerated the earth. You need to slow it down. That will cause it to fall towards the sun. But as it falls towards the sun, it will speed up again because it's falling towards the sun, and then it will loop around the sun and then come back out to the current orbit and then come back in. Come back out, come back in. It will turn the Earth's orbit when you accelerate an object in orbit. And I could do a whole episode on orbital dynamics. Feel free to ask. When you accelerate an orbiting object, you give it an elliptical orbit. A long, stretched out skinny ellipse that gets faster when it's close to the sun begin in, but then gets really, really slow on its way out.

So to park it in the new orbit that's closer to the sun, you have to re accelerate it again at the inner orbit. You need to kick it again to make it stick. I like to think of a ball at the top of the hill. You're at the top of the hill. I'm at the bottom In order to get the ball to me, you have to kick it. You have to impart energy on the ball, and then the ball starts rolling. And if I don't do anything, the ball is gonna roll right past me. So me at the bottom of the hill, I have to kick it again in the opposite direction to get it to stop. So you have to put in energy at the beginning and put in energy at the end. We can calculate how much energy this requires. Let's say we move our earth to 1/10 its current orbit. Why that number? Because, I don't know. I picked it. That's about twice that of Mercury's orbit. Nice and close to the sun, Nice and hot. That move doesn't come free. It costs 10 to the 33 jewels to make that happen 10 to the 33. So to unbind the earth you need around 10 to the 32 jewels, and then you need 10 times more energy to move the earth to a closer orbit.

But with a shell thickness of one kilometer. Being 10 times closer to the sun allows you to capture 100 times more solar energy. You cover 100 times more surface area, and so your payback time actually drops to around 10,000 years. You saved yourself 50,000 years of payback time. You just had to put in a lot of more energy at first. And if you play around with these numbers, if you assume an efficiency of 90% instead of 10%. If you assume a shelf thickness of 10 m, which is closer to Dyson's original estimate instead of one kilometer, you get something like a payback time of only a few decades. On the other hand, if your shell is 10 kilometers thick, 10 kilometers thick, which is not very thick, then you're looking at a payback time of half a million years. Even at that closer orbit, you just don't have enough material. So what about Jupiter? That was Dyson's original idea.

It is, after all, the biggest thing in the solar system. It's equal to over 300 earth masses. But like I said earlier, the vast majority of Jupiter is only hydrogen and helium, which are not exactly useful building materials. Yes, I know that fusion exists, but I'm not even going to start on the energy calculations involved in that. We don't know exactly what the rocky contents of the outer worlds are, but estimates for Jupiter put it somewhere around five earth masses of a rock in the deep interior of Jupiter. So with Jupiter, we have a nasty problem. We have to unbind the whole thing. We have to unbind all 300 earth masses worth of stuff to get at the crunchy inter bits. But we only get to use five earth masses for our solar energy harvester for our Dyson sphere. Dyson originally estimated the payback time of Jupiter to be less than 1000 years, but he missed this difference. The mass You have to unbind versus the mass you get to use.

And he neglected to account for the energy. You need to move Jupiter to a different orbit. Keeping Jupiter in its current orbit and dismantling it would cost a whopping 10 to the 36 jewels. And with one kilometer thick panels, you only get around 10,000 Earths worth of surface area for the effort, which is a lot. That's a lot of surface area, plenty of, um, living room. But at that distance at the orbital distance of Jupiter. Your payback time is several billion years because you don't have a lot of material that you can actually work with moving the panels these kilometer thick panels. They are kilometer thick Dyson sphere, moving it to 1/10 the orbit of the earth. Nice and close costs a lot of energy costs a lot of energy, but you get a lot more bang for your buck because you're closer to the sun. It brings the payback time down to a few million years, which is nicer but still annoyingly long and much longer than the original 800 years that Dyson estimated.

If you keep Jupiter at it at its present orbit and use it to build the Dyson sphere, that's a meter thick, which scarily thin with 90% efficiency. It's a few 100,000 years payback. You have a lot more surface area to deal with. Now, if you take that meter thick, panel the absolute most optimistic projection. Move it to 1/10 the orbit of the earth. You have 90% efficiency. Have panels that are only a meter thick. Your payback time is a few 100 years, it's all over the place. My point with these calculations is that it's not obvious that we can easily rearrange the solar system to make a Dyson sphere the energy payback time. And I'm not even talking about the technology needed to actually unbind the Earth and the energy needed to put into rockets and rocket fuel or propulsion mechanisms. I'm just talking about the raw, binding energy of these worlds. The energy payback time could be anywhere from a few centuries to a few billion years, and we don't know where we might land.

It depends on technology development, the actual distribution of materials. It's not guaranteed that we in the far future or any other advanced civilization will ever build a Dyson sphere. Because anyone can make these calculations. You just say, Well, it's just pointless because I need to disassemble this giant planet in my solar system and build solar panels out of it, and it's gonna take 500 million years for me to get my energy back. Or maybe not. Maybe it will only take a few millennia to get my energy back. I don't know. It's not guaranteed that we are gonna build Dyson spheres. They're certainly possible, but it's not guaranteed in this calculation. Might partially ex I should probably write this up in a paper or something like an actual scientific paper, but this might partially explain why we've never seen any Dyson spheres. We've done searches of nearby stars, any star we can get our hands on. And and the latest guy, a data set has over a billion several billion stars cataloged in the Milky Way galaxy.

None of them look like a Dyson sphere. We've done surveys of entire Galaxies, and you assume that if you're advanced enough to build the Dyson sphere, you're advanced enough to travel amongst the stars and build other Dyson spheres. And the universe has been around for billions of years, So you've had plenty of time to do this. And so your entire galaxy should shift because a large fraction of the stars are turning into Dyson spheres because you have this unbounded need for energy. Uh, we have we haven't seen anything. We see no Dyson spheres out in the real universe, even if it's possible. Even if the payback time is a few 1000 years, it doesn't mean we'll do it. Dyson's arguments assumed that the Earth's population would continue to explode and that our energy needs would continue to grow at an accelerated rate. That's not necessarily true. Progress is not a fact of life. Technological development is not a law of nature. Continued population growth and continued expansion of energy needs is not necessarily sustainable forever.

Our population growth rate has already slowed in the 60 years since Dyson wrote his paper. And, yes, we're using more energy than ever before. But that doesn't mean that in 1000 years or 10,000 years, we're going to use even more energy. Maybe we'll be smarter with our energy use. Maybe there'll be fewer of us. Maybe we'll just hang out here. Yeah, uh, technological progression and development at this rapid of a scale has been a feature of some cultures on the Earth for a short period of time, but that's not necessarily guaranteed to carry us forever. Maybe we'll return to hunter gatherer lifestyles. Who knows? We may never need that much energy. We may never want that much energy. It could be that Dyson's fears are just outright, impossible and never make sense. It could be that they do make sense, but we don't want to bother. We're talking about making predictions about the future of human humanity thousands of years from now.

Do you think our ancestors thousands of years ago would have been able to predict the world as it is right now? What makes us so arrogant to believe that we can predict thousands of years ahead of us? We simply don't know what we're going to get. Maybe we and other advanced civilizations, whatever you want to define as advanced, won't be building Dyson spheres. Not because it's impractical, but because we don't want to. But again, it's possible, thanks to Alex Kay Rock H on Patreon and Stephen on email for the questions that led to today's episode Thank you to my top patreon contributors this month. They are Justin G, Chris Barbeque, Duncan M, Corey D, Justin Zelia, Scott M, Rob H, Justin Lewis, M John W, Alexis Gilbert, M Joshua, John S, Thomas D, Simon G and Aaron J. Is all of your contributions that build this wonderful shell of science surrounding complete knowledge of time and space that's patreon dot com slash PM Sutter hashtag ask us spaceman at Paul Sutter on all social channels.

You can also find me. Ask a spaceman at gmail dot com. Ask us spaceman dot com for the website and all the old show notes and everything the show archive and I will see you next time for more complete knowledge of time and space.

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