How hard is interstellar travel? What are the possible ways to achieve the required energy? Is there anything at all feasible in the works? I discuss these questions and more in today’s Ask a Spaceman!
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EPISODE TRANSCRIPTION (AUTO-GENERATED)
We've accomplished a lot to change the world around us. We've developed agriculture and technology and industry and frozen yogurt. You know? It seems pretty good. Feels really good to sit at the top of the food chain.
We've spread to all seven continents in every possible climate. We we dive under the oceans. We over the Earth. We can't control the weather, but we can predict it with actually frightening accuracy when you think about how complicated the weather is, but that's a different episode. We've eradicated diseases, and then we brought some back just for fun, I guess.
We've made our homes comfortable wherever we place them. Like, I can just have the temperature I want inside my home, and that's pretty cool. We've measured and recorded every possible facet of the Earth and life on it from the tiniest virus to the ocean currents themselves that span the globe. Some days it really does feel like we're in charge, doesn't it? But for all our accomplishments and feats of ingenuity and creativity, we can't ever forget one simple fact.
In the end, mother nature demands respect. Sometimes nature reminds us not to let our pride turn into arrogance, not to let our achievements turn into hubris. Nature is still the boss around here, and sometimes she's gonna remind us why. And perhaps the greatest way to demonstrate that we don't have it all figured out is interstellar travel. Interstellar travel.
Who doesn't dream of traveling among the stars? Really boring people. That is the answer of for people who don't dream of traveling among the stars. I mean, it's like the staple of science fiction. You know, this is just, like, you look at the stars, you know they're out there, you know they're far away, but a finite distance away, and that they contain so many mysteries and so many cool things that would just be fun to look at or visit or fly by.
It just we just wanna go there. Who cares if there's another planet Earth out there? Maybe there's just, like, really, really neat stuff. That's why we wanna travel interstellar, for the neat stuff. But the spaces between the stars is vast.
It's hard to put a word on it. It's big. It's huge. It's tremendous. Gigantic.
It's big McLarge hues. It's basically impossible to describe or even comprehend the distances between the stars. It's totally outside all of our normal everyday Earthbound experiences. It's foreign. It's alien.
It's just let me give you an example. Think of what you did yesterday. What did you have for breakfast? How was work? How were the kids?
How was your mood? There's a pretty decent chance you can remember it and even some of the details with just a little bit of every I'm not sure if I remember breakfast, but if you think about it like, oh, yeah. It was it was a muffin. I Hope it was a bran muffin. You can remember yesterday.
How about this date four years ago? What did you have for breakfast on this date four years ago? You might have a little bit tougher time because this scales are totally different. The difference between yesterday and four years ago is a big deal. Now imagine walking across the football field.
If you don't know how big a football field is, doesn't matter. It's, like, walkable in a relatively short amount of time with not much effort. You could walk across a football field. Now, walk a hundred miles. Think about walking across a football field versus think about walking a hundred miles.
It's a vastly different sensation, just totally different. Voyager one, one of our space probes, is the furthest space probe we have away from the Earth right now. It is twenty light hours away, which means it takes light going as quickly as it can, which is pretty fast. Twenty hours to reach go from us to Voyager one. Voyager one to get twenty light hours away, it took Voyager one forty years to get there, traveling at 18 kilometers per second or 40,000 miles per hour, whichever you prefer.
They are both big numbers, and a long time is twenty light hours away. Our nearest star, Alpha Centauri, is 2,000 times further than that, which means that Voyager one was pointed at Alpha Centauri, which it's not, but if it were, it would take it eighty thousand years to reach it. Eighty thousand years. Twenty light hours versus four light years is the difference in scale we're talking about. It took us forty years of travel time traveling really fast to get twenty light hours away.
That's like remembering something you had for breakfast yesterday. But the nearest star, Alpha Centauri, is four light years away. That's trying to remember what you had for breakfast four years ago. Took us forty years to reach the twenty light hours. It will take us eighty thousand years to reach the nearest star.
Can can we all just take a take a break here And just breathe a little and just acknowledge those numbers? Eighty thousand years to reach the nearest star? I mean, it takes us years just to get anywhere in the solar system. And that's peanuts. Like, oh, we wanna design a mission to Saturn.
Yeah. That'll take, like, eight years. Eight years. And that's nothing. That's just the solar system.
That's peanuts. Scale wise, when it comes to galaxy, you might as well not even bother to leave the Earth. You've gone nowhere. These kinds of scales to get to the nearest stars demand respect, don't they? You can't just wave your hands and say, oh, it's something we'll figure out.
We'll we'll solve that problem. I mean, come on, people. And I promised I'm not gonna turn this episode into a rant, but it's probably gonna turn into a rant. There's simply no frame of reference we have in our monkey brains to be prepared for these kinds of distances when it comes to travel between the stars. We just got nothing.
You can't point at something like, yeah. Yeah. It's like this in our evolutionary heritage that allows no. So stop, please. Is interstellar travel possible?
Yeah. Look. I'm very rarely going to say on the show that something is impossible because in order for something to be impossible, there has to be, like, a law of physics that prevents that thing from happening. And even then, laws of physics aren't firmly fixed. They are guided by evidence.
And if evidence changes, we may have a new understanding. So the most I can say is according to our current laws of physics, this thing might be impossible. Interstellar travel is possible, but there's a vast difference between possible and plausible, and an even vaster difference between plausible and feasible, and an even vaster difference between feasible and achievable in our lifetimes, which is what we really care about. Who cares if humans a thousand years from now could travel among the stars? We don't get to be a part of that.
So it doesn't matter. We'll be good job future humans. Why couldn't you figure it out earlier so that we could do it? That's what we care about. We wanna know, is interstellar travel achievable within our lifetimes?
Interstellar travel is not impossible, but the real question is where on that spectrum between possible and achievable in our lifetimes is it really? That's the question we wanna ask. That's what we care about. And I'm gonna admit my bias here right at the top so you know exactly where I'm coming from. I think interstellar travel is nearly impossible.
The challenges to traveling between the stars are so hard, and we would require so many resources pull it off that to me and just me personally, it's not even worth wasting brain cells on. Like, if you think of the problems, the engineering challenges that we face, and the things we'd like to solve and accomplish and explore, trust me, that spirit of of going out into the unknown, I've got that bug. I I feel it. Like, I would love to go between the stars, but it's also really hard. Really hard.
And I'll take the rest of the episode to explain why it's so hard. But it's right there to me. It's like, it's so hard. Maybe we should think about other things. Maybe it's a waste of time.
But this is a matter of opinion. This is my opinion that it's nearly impossible. You're welcome to your opinion even though you're probably wrong. I'm kidding. I'm kidding.
I wanna use this episode to explain some cool physics in the form of talking about some projects to answer the challenges of interstellar travel and what those challenges are and what the physics are based on. Like, that that's the goal of the episode. If it comes out sound sounding ranty, I'm sorry. I didn't write it that way. I didn't sketch it out that way, but, you know, rants are rants.
They just come out of nowhere, and they consume you. Poor me. I'll speak for myself. Anyway, is interstellar travel even possible? Yes.
Is it nearly impossible to me? Yes. And but big question is, is it achievable within our lifetimes? I don't think so, and I'm gonna explain why. Let's explore some options for traveling between the stars.
Option number one, we're already doing it, folks. Yay. Humanity, Voyager, Pioneer, New Horizons. Either these missions have already passed the boundary of the solar system, which we define loosely. I mean, you can have any definition you want.
We're gonna define it as where the solar wind, which is this stream of subatomic particles, coming off the sun, constantly raining off the surface of the sun. They fill up the solar system, and then they reach a boundary where they mix with all the other subatomic particles from all the other stars all across the galaxy. And there's almost like a bubble edge to that where it changes where you cross that boundary and, I don't know, and it tastes different out there. That's one boundary of the solar system. It's a pretty useful one.
The Voyager probes, at least one Voyager probe has already made it. The other one seems to be right at the boundary. The Pioneer and New Horizons, they are approaching it, and they are on escape trajectories, which means they, of course, feel the gravity of the sun, but this the same way a rocket feels the gravity of the earth. Just because it feels it doesn't mean it's coming back. It is gone.
It's gonna be gone forever. They're already halfway out the door. So they are technically interstellar. They are in the spaces between the stars. Interstellar.
Done. Okay. But the instruments onboard will soon be dead, soon ish. They're powered by radioactive decay of elements that heat up one side of a thingy. I'll call it a thingy.
And the other side stay cold, and that generates an electric current, and that powers the instruments. The Voyager ones are almost dead. Almost dead. And then New Horizons, I think, has twenty or thirty years left in it of a little bit of power. So in very short order, they're gonna be just hunks of metal hurtling through the void.
Okay. You know, they'll be out there, and after our sun turns us into charcoal in four and a half billion years, those space probes will still be out there because they're not really aimed in any particular direction. I mean, they were aimed in directions in our solar system to study planets, and now they're past that and they're doing their own thing. And they're just, you know, flying through space. Isn't that fun?
That's about it. I mean, it is technically interstellar space travel, but tossing rocks and chunks of metal around, it sounds pretty fun. It's not really what we think of as productive space travel. We want we want to do something with our space travel. So it is an accomplishment, but not really the interstellar we were hoping for.
Okay. So that option's out. What about option number two, which is people going to the stars? I'm not even gonna go there. Why?
You might ask. Thank you for asking. I'm not gonna answer. It's just I'm not even gonna bother. We're gonna jump right to option number three.
We want to send space probes to other stars, and they can take some pictures, collect some data, do some sightseeing, you know, get a stamp on their passport, get a commemorative magnet, and send that stuff back to us, or at least the pictures part, and tell us what they saw. And we can see a picture of an alien star right up close or maybe another planet right up close. Okay. That is that seems more reasonable. Big huge problem is, like I said, the distance.
Sure, the Voyagers and New Horizons will eventually get there, but who's running mission control for eighty thousand years? In order to conquer this distance, which really this is straight up a problem of distance. In order to conquer the distance, we have to go really, really, really fast, like, say, 10% of the speed of light. If we could send a space probe at 10% of the speed of light, it would make a mission approximate Centauri, our nearest neighbor, forty years. Forty years.
That's assuming a flyby and no deceleration because if you want to slow down, then that's gonna add time. You have to accelerate your spacecraft. It has to cruise for a while and then has to slow down to go into orbit or to do hang out longer in that in that system. That's gonna at least double your time. So if we just want a fly by, snapped a quick picture, send it back to Earth, that's a forty year mission.
That's within, you know, a human lifetime. The same person who starts a mission could see the result of that mission. That seems achievable or or that seems reasonable, a reasonable ask. Can this bare minimum definition of interstellar travel happen? Well, to get to the 10% of the speed of light, you need energy.
Right? You need to go fast in your when you launch off the Earth, you're not really going very fast. So you need to you need a lot consume a lot of energy to get that fast. So the energy, you have two choices. Either you carry the energy with you, which is something we call fuel, or you don't.
Let's say you carry it with you like a rocket. Rockets carry their fuel with them. That is not gonna work. Why? Because rockets, the chemical reactions in a rocket that make it go and make the big blast and all that, and it's very impressive, actually don't have a lot of oomph.
I mean, they have a lot of oomph, but not 10% of the speed of light oomph. You could do it. You could say, okay. I am going to push my rocket with fuel to get it up to the 10% of the speed of light. But because the chemical reactions don't deliver a lot of oomph, then you need to carry more fuel.
You're like, okay. I'll just instead of getting it all done at once, I'll just take my time, and I'll have a lot of fuel. And slowly over time, it will push my spacecraft faster and faster. But that means you have to carry a lot of fuel. And if you carry a lot of fuel, that's gonna increase your mass.
If you increase your mass, that's gonna make you even harder to push. Oh, so if it's harder to push, you need to carry more fuel so that you can get up to 10% the speed of light. But if you carry more fuel, that's gonna increase your mass, which is gonna make you harder to push, and and then it just cycles out of control and you find out that you just really can't get to 10% of the speed of light with a rocket. We need a different kind of fuel. We can't use the chemical rockets that are good for getting us off the ground.
How about nuclear bombs? I mean, they seem impressive. Right? They seem to release a lot of energy, And you can imagine dropping a nuclear bomb back behind the trunk of your car, and it might just push your car around pretty efficiently. Or at the very least, you put a nuclear reactor in the trunk of your car, and then you cut a hole in the back of it as an exhaust, and, you know, fire it up, and that's there's gonna be a lot of energy released.
Nuclear reactions are very, very efficient. They they release a lot of energy, and if you can harness that energy and turn it into momentum and movement, you've got something going on. There was a design for a project called Project Orion, which was a concept for an inner interstellar spacecraft that dropped nuclear bombs off the back end, had something called a pusher plate because, obviously, there is this slight technical challenge of wanting to drop nuclear bombs off the back of your spaceship without destroying your spaceship by a nuclear blast. And so there's a very fancy complicated pusher plate that, you know, absorb the energy and push your spacecraft along. Kinda challenging to make that spacecraft work and get to 10% of the speed of light because you need, like, more nuclear bombs than have ever been produced by all of humanity.
Okay. There was another project called project Daedalus that used a nuclear reactor with a hole cut out of it, push things around. If you wanted and then this reference design, they wanted 500 tons of science, like, the actual spacecraft was 500 tons, it still required 50,000 tons of nuclear fuel to feed into the reactor over the course of decades to get it up to 10% the speed of light. So the advantage of this kind of nuclear based interstellar rocket is that you have the energy. Like, you know what?
If we wanted to make a whole bunch of nuclear bombs, we could. If we wanted to gather 50,000 tons of fuel and put it in a rocket, we we kind of could. General problem is that's a lot of stuff. That's a lot of manufacturing output. Another problem is that you need to keep this rocket going for decades.
So it's not just dropping one or a couple or a baker's dozen of nuclear bombs off your back end. It's doing thousands of them over the course of decades. Do you think we could reliably make something? A spaceship that could operate for decades with nuclear bombs being dropped off its back end. Maybe, but it's kind of a stretch.
Do you think we can make a spacecraft with an operating nuclear reactor that can operate for decades continuously with no, you know, problems? Kind of a stretch. And this is the problem. When you want to carry your own fuel, it makes you big and heavy, which means you have to do the whole acceleration thing for a lot longer than you might be comfortably prepared for. And so there's another trend.
If you can't carry your fuel with you, maybe you keep the fuel somewhere else. This is best represented by something called the breakthrough starshot initiative, which is a small, tiny spacecraft that is propelled by something else, where the energy is stored or generated somewhere else and then delivered to the spacecraft, and then that makes the spacecraft go. How do you get energy from one place to another? There aren't all especially a lot of options, so I won't keep you in suspense. We're gonna use lasers.
That's right. Lasers. Lasers carry energy. I can shoot you with a laser and melt you. I have taken energy from my laser and put it on your body and made your body melt.
That is a transfer of energy. The overview of something like Breakthrough Starshot Initiative is that you have a very, very tiny spacecraft, and you have lasers on the ground shooting at the spacecraft. And where this doesn't go haywire is that the spacecraft has a light sail attached to it. A light sail is exactly what it sounds like. It is a sail for light instead of, say, the wind.
It's something that's very, very reflective, super reflective. And so the laser shoots at the spacecraft, and it bounces off the sail. Now light has energy, and light also has momentum. Light can literally push things around. This is the pressure from light.
And so by bouncing the light off of the sail, you can push the sail and push the spacecraft. The goal, again, is to get the spacecraft to around 10% the speed of light. That puts the missions to the nearest stars within human lifetimes, you know, a few decades. This isn't gonna be a mission that's gonna slow down. That's, like, way too complicated.
So these are gonna use flybys. So we're just gonna accelerate these spacecraft, and they're gonna go. And then they're gonna zip by their destination. They're gonna take some pictures, and we want them to get the information back. This is where the light sail comes in handy.
Again, because the light sail can be reconfigured to turn into an antenna because it's, you know, made of metal, presumably. And the spacecraft could carries all, you know, radio, transmitter, and all that, and it beams it back to Earth and we can listen. Okay. Okay. This isn't sounding so bad.
Let's say you wanna use lasers to push something around. Like, I got a laser, you got a light sail, let's see what we can get going here. You're gonna need a lot of lasers. This Project Starshot calls for around 100 gigawatts of lasers. It's not just one laser, but it's gonna be a whole bunch of lasers operating in concert to get the peak output at a hundred gigawatts.
To give you a sense of how much energy that is, that is all the nuclear power plants in The United States operating at the same time. I'll say it again. The Breakthrough Starshot Initiative calls for a laser to shoot at these light sail spacecraft of around 100 gigawatts. That is all the nuclear power plants in The United States operating at peak capacity at the exact same time, all being fed into a laser or a bunch of lasers working together. What is the force if I shot you with a hundred gigawatt laser and you didn't melt?
What is the force, the the force from the light pressing on you? Have you ever dropped a few books? You know, imagine carrying a few books in your hand and you drop it. That is the amount of force from a hundred gigawatts worth of laser. Letting that sink in.
Yes. Light can push on things. It doesn't do a very good job because it's light. It's not heavy. That's why we call it light.
I'm not sure if that's why we call it light. If you've ever dropped a few books on the floor, the force imparted or imagine you're laying on the floor, and I drop a few books on you. Don't worry. I'm not gonna hate hurt you. I drop a few books on you and you're like, ow, but you're generally okay.
That's 100 gigawatts. All the nuclear power plants in The United States diverting all their energy 100% efficiently into a laser and me shooting you with a laser. Assuming you didn't melt, you would just say, oh, I'm okay. So to make this work, to actually push a spacecraft with a hundred gigawatt laser, the spacecraft has to be really, really, really, really tiny. Because if it's any heavy at all, this could take forever.
How tiny? A gram. The reference design for Starshot Initiative is a gram. Folks, that's a paperclip. Paperclip.
The math works out that if you shoot a paperclip with 100 gigawatts of lasers and it can reflect all that light, in about ten minutes, you'll get that paperclip to this 10% the speed of light. Ten minutes, one hundred gigawatts, one gram, 10% the speed of light. Go. Okay. So let's say we figure out the giant laser, which is, you know, a mild engineering problem, and we're able to design this this this light sail.
We can send paperclips to other stars, which is cool in a way. We could see the galaxy with paperclips. That'd be so much fun. That'd be our signature where billion years from now, another alien civilization will find all these artifacts. They say, wow.
What an advanced civilization. And it just so happens that I've got a bunch of loose leafs of paper that could really use some clipping right now. And thank you, ancient dead civilization, from eons ago somewhere in the distant galaxy for solving this technological problem for us. We would have never figured it out on our own. Okay.
We don't wanna send paperclips. We wanna send legit spacecraft. What what who does this spacecraft need? A spacecraft needs a computer, needs a battery, needs a camera for those pretty pictures, needs a shell, a container, and it needs to have the light sail itself. And it needs, like, power supplies and communication gear and, you know, little ways to propel itself, you know, to change your alter course as it's going.
You know, spacecraft is kinda complicated. Lots of things going on in spacecraft. I won't get into the engineering challenges of making the spacecraft work because you have to cram all that into a very tiny volume and make it weigh less than a gram. But that seems like an engineering problem. That's actually the focus of the breakthrough starshot initiative is the spacecraft itself of how can you miniaturize all the components of a spacecraft to make it weigh less than a gram.
I wanna talk about some of the physics problems. One of the physics problems is that you need a powerful laser. The most powerful laser right we have right now is one kilowatt sustained, and we need to get up to a hundred gigawatts. Kila, mega, giga, hundred giga. That's a lot of watts.
It's hard to make big lasers because they tend to heat up because they're not perfectly efficient. You lose some energy, and so that makes the laser itself nice and warm. It's hard to make them reliable because you have to get, you know, so many things in sync. Like, you need a, you know, a chamber with a gas in it or fiber optics, and you need everything to work in sync perfectly and synchronize over and over, like, very, very quickly, quick cycles. And that's just, like, a reliability thing.
And the materials itself, like, think of what it takes to make a laser, and now you gotta scale it up, like, a bajillion times. It's hard to make powerful lasers. It's hard to redirect all those kinds of energies into laser form. It's just tough. The best we can do now is a kilowatt, and then you gotta go up to megawatt, which is a thousand times bigger, gigawatt, which is a thousand times bigger than that, and then a hundred gigawatts, which is a hundred times bigger than that.
So a thousand times a thousand times a hundred. Like I said, a bajillion. Another challenge is the light sail itself. You can just say, oh, we'll make something really shiny. But if it's I mean, you're shooting a giant laser at it, folks.
If it absorbs even a tiny bit of light, it just melts. That turns into heat. That that doesn't turn into momentum. So if you're, like, 1% absorbent, if you're only 99% reflective, you're just gonna melt it because you're shooting a giant laser at it. It has to be almost perfectly reflected, more reflective than any material we've ever developed just to deal with the heat.
And also the laser and the sail have to be almost perfectly aligned with no imperfections. Like, if you're gonna keep your laser on the ground, which makes sense because you need a lot of energy, you're gonna shoot it through the atmosphere at the spacecraft, which is orbiting. And if the atmosphere shifts a little, that's gonna shift your laser a little bit. And then think about it. You're pushing something for ten minutes, and then you're letting it go.
If you get it wrong, it's not gonna head to Proxima Centauri. It's gonna go anywhere else that isn't Proxima Centauri. Like, this has to be perfectly perfectly aligned. So if there's any imperfections in the light sail, if there's any misunderstanding about the orientation and position of that light sail, if, you know, the winds blow a little bit off that day, then you just shot the world's most expensive spacecraft into the middle of nowhere. Is there a challenge for this?
There's a you know, or is there an answer to this challenge? Sure. If you can contribute to patreon.com/pmsutter, I will not develop an accurate light sail. No. Instead, I will continue to do my shows describing the awesome and wonderful and beautiful physics and astronomy in the universe around us.
And I'll do so many other cool things. Go to patreon.com/pmcenter. But I will tell you, if you contribute, none, absolutely zero of that money will go to light sail development. I promise. But let's say you do it.
Let's say you got the giant laser. You have your super effective light sail. You have your gram paperclip spacecraft that's an actual spacecraft, not a paperclip. You shoot the thing and it goes. One of my favorite challenges that these missions have to face is dust.
You know, space is very much empty, but not totally empty. It's a vacuum, you know, as registered here on the Earth, but not really a vacuum. There's still stuff. There's still particles. There's still grains of molecules just hanging out, minding their own business.
And then out of nowhere, whammo, there's this light snail spacecraft traveling at 10% the speed of light. Like, woah. Come on, buddy. These little dust grains are gonna impact the spacecraft at 10% the speed of light, which is fast. And that little dust grain, even though it's tiny, is gonna be mighty when it gets hit by something going 10% the speed of light.
It's gonna cause damage. It's gonna pick apart the spacecraft. It might blow a hole in the light sail. It might carve through the shielding and mess up your electronics. We don't exactly know how much or how distributed the dust is between us and any given star, and we have a rough idea.
But say you prepare for that and develop the right shielding and you angle your spacecraft so it's, like, edge on, etcetera, etcetera. Man, it could just be a bad dusty day. Our light sail spacecraft may not even make it past the edge of the solar system. They're just too fragile. And so you're like, okay.
Well, we gotta beef them up, but, no, you got a paperclip worth of mass to deal with. So you get beefing up isn't really an option. There's another related challenge, which is the cosmic rays. These are the high energy particles emitted by, like, supernova and giant black holes across the universe, completely soak the cosmos, gets worse once you exit the solar system because our sun's magnetic field helps protect us, and some of the nastier ones don't even make it inside the solar system. You get outside that protective bubble.
Man, it ain't pretty. Cosmic rays can mess with your delicate circuitry. You may survive the dust just fine, but then your brain is cut apart. And you think, okay. Well, we just get some shielding.
No. You can't do the shielding because you have to be tiny. Even though I said at the beginning of the episode, it's all about distance, it's not. Surprise. Nature demands respect.
Could this work? Could project Orion or Daedalus or Starshot work? Yes. They're all possible. It's possible that we could collect enough resources.
It's possible that we could overcome these engineering challenges. It's possible that we could try and try and try again and come up with the solutions to the challenges that we haven't even thought of yet. But could we really, in the foreseeable future, come up with the right mix of technologies to do it? That's where it becomes more difficult for me. Because, yes, you can you can say, like, yes.
We'll make a tiny spacecraft. We'll make a super reflective light sail. We'll make a giant laser. Like, we'll we'll answer all these problems, but how much money is it gonna take? Will it take more money than the world, like, has right now?
More resources than the world even has right now? Will it take more money, more resources, more time, more effort than the world will have a hundred years from now or a thousand years from now. It's impossible to put a timeline on any of these, except my personal opinion. Just looking at the challenges, it just doesn't seem feasible in the coming decades. That's a matter of opinion.
It's my opinion that we shouldn't bother spending money on interstellar missions because the challenges are just too big. The physics is too big. Nature, mother nature is demanding our respect. Thank you so much to at Infirmus, Amber d on Facebook, Neo via email, Alex v on Facebook for asking questions that led to today's episodes. And please please go to patreon.com/pmsuter.
That's Paul, m as in Matthew, suter, s u t t e r. To help keep these episodes going, big thanks to my top contributors this month, Matthew k, Helga b, Justin z, Matt w, Justin g, Kevin o, Duncan m, Corey d, Kirk b, Barbara k, Nooter, Drew, Christy, Robert m, Nate h, Andrew f, Chris l, John Elizabeth w, George Cameron l. Should make a song out of those names. That'd be more fun. Go to patreon.com/pmsutter.
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