How do planets get tidally locked? What are these systems typically like? Can life find a home in such a challenging environment? I discuss these questions and more in today’s Ask a Spaceman!

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EPISODE TRANSCRIPTION (AUTO GENERATED)

The famed science fiction author, Isaac Asimov, called to them Ribbon Worlds. Planets forced to always show one face to their parent star. The star side would be locked in perpetual day, its sun never dipping below the horizon. Indeed, its sun never moving at all. Fixed in place as if time itself stood still.

The far side would be trapped in perpetual night. A sky blazing with the light of a 1000 stars, never knowing the warmth of its own parent. And in between the two extremes, a special place. A terminator line, the boundary between night and day, a region of infinite twilight, or depending on your perspective, perpetual dusk. Caught between the 2 poles of heat and cold, this ribbon that stretches like a girdle around a planet might might just be a home for life.

Neither too hot in the never ceasing glare of the star, or too cold in its infinite night. At the time that Asimov coined that term in the 19 fifties, astronomers still believed that Mercury, the innermost and smallest planet of the solar system, was in such a state, And speculation abounded about whether it could possibly support a strange form of life in the narrow ribbon of its own terminator. But soon, observations revealed that Mercury does indeed rotate just extremely slowly. There are worlds in our solar system that are indeed locked this way, but they are all satellites. Our own moon is like this, always presenting the same face to observers on the surface of the Earth.

Indeed, despite our intimacy with our nearest of cosmic neighbors, it wasn't until the 1950s that we humans got our first hazy glance at the far side of the Moon. This frozen face is given a technical term because, of course, it is, and it's known as tidal locking. The source of tidal locking is well, we actually have it a little easy here because this is a rare case of the technical jargon term actually describing the physics. Here's how it works. We all know that the Moon raises tides on the Earth.

The side of the Earth closest to the Moon gets pulled a little bit extra, and the side farthest from the Moon gets a little bit left behind. But the Earth also raises tides on the Moon, and those tides are much stronger. Yes. I know that the Moon is made out of rock, but even rock is a little bit squishy when you have enough gravity to work with. And if we go back way billions of years ago to the beginning of the Earth Moon system, we can see how the raising of the tides led to a locking state.

So both the Earth and the Moon were initially spinning on their axes at their own race. You know, the the Earth is doing this, spinning around. The Moon is going around the Earth and also spinning on its own. What happens is that the Earth raises the tide on the Moon. The Moon gets a little bit squishy, little bit pulled towards and away from the Earth.

Then the Moon tries to spin away. It does its own normal spinning thing and and it tries to take that lump of moon stuff away from the Earth. And I like to imagine here a little leash made of gravity. The moon is spinning, trying to bring this lump of stuff further away from the Earth, but the gravity of the Earth tugs on that lump of moon stuff like a leash. It's like training a dog here.

This is basically tidal locking. Use your dog training. And the earth pulls on that leash a little bit. It's not much. It's not going to have an immediate effect.

But what happens is as the moon tries to spin away, it gets slowed down just a little bit. And then the next time around, there's another tide. It spins around, tries. It loses a little bit of energy, a little bit of energy, a little bit of energy. The moon becomes more and more lopsided, and then it ends up matching its own spin rate with the rotation rate.

So the the moon is spinning. It's just spinning at the exact same rate that it's orbiting the Earth so that this lump of moon stuff that was raised by a tide on the moon, a tide made of rock, is always facing the earth. This is the lowest energy configuration. This is the most stable configuration. The moon just got tired of trying to fight the earth.

It's like a dog that finally gives up to just to get the treat. Fine. I'll heal. I'll do it as long as I get the treat. The treat is tidal locking.

The moon is also doing it to the Earth. The moon is raising tides on the Earth. It is introducing this slowness, but because the moon's gravity is way weaker, it will never finish the job in the 4 and a half 1000000000 years we have left in the life of the solar system. This happened with the Earth Moon system. It can also happen in solar systems just like it almost happened to Mercury.

What happened with Mercury though is that there's also Jupiter introducing its own gravitational tugs that pulls Mercury out of that tidal locking. But if you're a random planet around a random star, you run the risk of tidal locking. On the Earth, half of our tides come from the moon, and the other half come from the sun. Even though the sun is super far away, it's super giant, raises tides on the earth just like the moon does. And if the sun were bigger or the earth were smaller or we were closer together, when those tides are bigger, the gravitational interactions are stronger, you run the risk of tidal locking.

And so when we go out and look at exoplanets, planets orbiting other stars, we see a lot of cases where we're pretty sure tidal locking is going on. Anytime the planet is small and close to its parent star, it runs the risk of tidal locking. So what does this have to do with life in Isaac Asimov's ribbon worlds? Well, turns out there is no life on Mercury, at least as far as we can tell. But we've just begun our searches for life in other systems in earnest, and we've discovered thousands of exoplanets.

There are probably 1,000,000,000,000 of exoplanets in the entire galaxy, but we haven't seen most of those. And, in fact, our techniques for finding exoplanets are very limited and right now very biased. You know, the most popular method for identifying exoplanets is something called the transit method. The transit method is when we stare at a star and wait for a planet to cross in front of it, and we notice a little dip in brightness because the planet is blocking out just a tiny bit of the star's light. This method works best when the planet is very large compared to its star, especially from our perspective.

This means the method works best when the star is relatively small and when the planet is relatively close. That way, a bigger percentage, a bigger bigger chunk of the star's light is blocked from our perspective, and we have a better chance of observing it. It doesn't mean this is the most common kind of planet, relatively decent sized planet. We're talking Earth sized planets orbiting very close to small stars. It doesn't mean this is the most common kind of planet.

It could be, but it does mean this is one of the easiest kinds of planets for us to find, and they are indeed ridiculously common. And it turns out small stars, red dwarf stars, are the most popular kind of star in the galaxy. So the what we know for sure is that there are a lot a lot of Earth sized rocky planets orbiting very, very close to small stars. And so if there's even a slim chance that they are habitable, we need to check this out because there are a lot of them. If you have a small probability of any one planet being habitable, but then you have a whole big mess of planets, you have a decent shot of one of those actually hosting life.

And we've seen this like the TRAPPIST 1 system, you know, these 7 earth like planets, a bunch they orbit a small red star, and a bunch of them are very very close to the star. Proxima b, the nearest known exoplanet to earth is exactly the situation. A rocky planet, earth sized planet orbiting very, very close to a small star. And we are finding a lot of Earth like planets orbiting small stars in the habitable zone where it's not too close to be cooked to death and not too far away to be frozen to death, but just right, just like the earth is in the habitable zone of the sun. These are also the planets that are most likely to be tidally locked because they are relatively small, like and, yeah, an earth sized planet is pretty beefy as planets go.

Yeah. But compared to a star, even a small star, it's peanuts. And these small red dwarf stars, their habitable zones are really really close to the star itself. These these stars are not very bright as in as in they're dim, like like, they're I'm sure they're intelligent if you were to have a conversation with them. I don't mean brightness like that.

I I I mean, in terms of luminosity, that that habitable region with just the right temperature for a small star like this is within the orbit of Mercury. In our own solar system with a medium sized star, the habitable zone is way out here, 93,000,000 miles away. But for a small star that's like a 10th, a 5th the mass of the sun, the habitable zone is right up against it. We're talking orbits of a few days at most, and that's exactly the kinds of conditions you need to title you lock because you have a small object orbiting a big object really really close. That's how you get title locking.

It turns out that at the present moment, with this incomplete senses of potentially habitable planets, that most of the known potentially habitable planets are likely to be tidally locked. So it becomes this big open research question, can tidally locked planets support life? If the answer is just no across the board, then we'll stop caring. I mean, a few astronomers will still care, but largely, we'll stop paying attention to them. But if there's a path to yes, if there's some way to make these planets habitable, then we better keep looking because they are so insanely common.

Folks, I need to pause to take a quick little break and mention that this show is sponsored by BetterHelp. I didn't realize how much physics stressed me out, especially as a student, until I started teaching it again. And I'm facing 50 incredibly smart and bright, but oh, so nervous and anxious and stressed out students. You know, you're fretting over this or that or the grade. It's a mess.

We all carry around different stressors, big and small. When we keep them bottled up, they come out. They really do, but they come out in strange ways, and therapy is a safe space to get things off your chest. Just talk about it to help navigate it. I have personally benefited from years of therapy of navigating all the stresses in my life.

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Get it off your chest with BetterHelp. That's betterhelp.com/spaceman. And when you visit that link, you get 10% off your first month. That's betterhelp.com/spaceman. So do rocky planets in the habitable zone of small stars that are likely to be tidally locked, can they can they host life?

You won't be surprised to learn that the answer is we're not sure. Can a tidally locked planet around a small star like this have the right temperatures, the right conditions to make liquid water possible on the surface, which is as good a starting point as any when we're searching for life. We're going to assume for now that life looks like the kind of life we know because we know what we're looking for, and that starts with liquid water. So if we can answer the question, can these planets support liquid water on the surface, that that goes a big way to determining if they're habitable. Like I said, we're not sure.

We do know that it's very easy for everything to go completely haywire with these tidally locked planets. We have the examples of the hot Jupiters, which are giant planets orbiting very closely to their parent stars, and they are so hot, they are glowing. They are destroyed. They are actually in the process of getting destroyed. I could do a whole episode on hot Jupiters.

In fact, I think I have. There are tidally locked planets or planets in interesting tidal configurations that are getting squeezed so much they are literally incandescent. So it's easy to go haywire. We do know that. Wherever we're going, we're going to ride a very thin line here, and it doesn't have to be a disaster.

We don't know for sure. We're only in the beginning stages of exoplanet exploration, and so we don't have a lot of hard data to go on. And last time I checked, which was 5 minutes before I started recording, we have not discovered liquid water, let alone life on the surface of any exoplanet. So we're guessing here. And to make these kinds of guesses to determine if these kinds of worlds are even potentially habitable, we're going to have to turn to models and simulations.

Planets, weather, climate, ocean currents, whatnot, these are slightly complicated systems. So we need to make things a little bit simpler. I would love to do an entire episode on mathematical modeling, simulations, please feel free to ask, that would be such a fun, potentially even series to explore, since I am rather fond of computational simulation in the sciences. But what we do in general, on very broad strokes, is we we don't have an actual planet that's tidally locked around a small star, and we can't, like, just stare at it. We don't have the data yet.

We don't have the telescope power. We can't study it for ourselves. We can't put it in front of the telescope and and just let nature tell us what's going on. So we need to build pretend planets, and we need to capture the physics of these pretend planets. We do it using computers where we we we have simple models.

We say, okay. There's land over here. Maybe there's an ocean over there, and then there's air on top of it. And we know how these things interact with each other. We know that the wind blows.

We know that the ocean carries currents. We know that the land can get hotter and cooler. It can absorb radiation or emit radiation. And we can use our knowledge of physics the same way we use our knowledge of physics to make weather forecasts, climate modeling. We know how all of these physical components of a planet interact with each other and behave and and evolve.

We try in our simulations to capture as many details as possible, but we're limited by time and resources and knowledge of physics of the intricacies of how these systems interact with each other, so we do our best. For example, we have some mathematical equations that describe how atmospheres transport heat, or mathematical equations that describe how radiation from a star heats up an atmosphere at different wavelengths, and so on and so on. It's not perfect. It's highly speculative. It's also the best we got, and it's kinda fun to do.

Here's our question. You've got a planet. It's tidally locked. It's probably tidally locked around a small red dwarf star. It receives heat from its parent star on the day side and doesn't get anything at all on the night side.

So only one side of the planet is getting heated up ever. Unlike the Earth which is constantly rotating, it's changing which side of the Earth is getting direct heat from the sun. With these tidally locked plants, we don't get that. Only one side is gonna get the blast. The question is, can life exist anywhere?

That's a very difficult question to answer. We'll we'll try to answer a slightly less complicated question, which is can liquid water exist anywhere? That itself is a complicated tough question, so let's just ask, can we have the right temperatures and pressures to allow for liquid water to stay stable on a surface? That's something we can more reasonably tackle with our knowledge of physics. Here's what we want to avoid.

We want to avoid, and the polite term here is atmospheric collapse. The implied term is a dead world. You can collapse an atmosphere either by boiling it off on the day side. If the day side of this planet is simply too hot, it will just evaporate the atmosphere. It makes the atmospheric gases so hot, they just fly off into space and you're done.

You've killed the world. You also need to avoid freezing out of the atmosphere on the night side where if it gets too cold, then all the beautiful atmospheric gases that are keeping a lid on things like oxygen, nitrogen, carbon dioxide, if it gets too cold for them, they just snow to the ground and become frozen, and your atmosphere gets locked away. It collapses and your planet dies. Losing an atmosphere means losing liquid water. You need that air pressure on top of a planet in order to keep liquid water stable.

So can there be a middle ground? Well, it's all about balance, isn't it? You've got the forces of light on the day side that are trying to heat up the planet, and you've got the forces of darkness on the night side that are trying to freeze the planet, and you must seek balance in the forces. Here's the thing. No 2 planets are exactly alike.

So it's not like you can just say, planets do this. No. They hate being typecast. Just look at our own solar system. Venus, Earth, and Mars are all in the habitable zone of the sun, and yet they are wildly different.

So that means we can't just run one simulation with one setup, with one model of one kind of planet, with one kind of atmosphere. We have to run a lot of different models trying different combinations of planetary characteristics to see what pops out. Maybe some are allowed and some aren't. If they're all not allowed, if there's if there's no way to have a stable atmosphere in liquid water, then we know, okay, like, we should stop looking. But if there are some plausible paths to maintaining an atmosphere in liquid water, if a large fraction of the models allow us, then, yeah, we need to keep studying, we need to keep working, we need to take some hard data.

To give you a sense of how complex and varied these simulations can be, here's what we can tune. We can change the distance to the star. Right? That will have a drastic impact just like it does with a normal rotating planet of how much energy that planet receives from its star. We can change the type of star because different wavelengths of light will affect atmospheres differently.

We can change the size of the planet, which changes how well it can hold on to water in an atmosphere gravitationally. We can change what the planet is made of. This changes the planet's reflectance, its albedo. You know, if the planet's made of super shiny stuff, then most of the radiation, the most of the light that hits the planet just bounces off and goes back into space, and it can't use that heat to stay warm. We can change how much water is already on the surface.

How deep that water is? Are we talking shallow lakes? Are we talking multi kilometer wide oceans? Is the planet completely submerged in water, partially submerged in water? How much what state is the water in?

Are there glaciers on the night side? You know, we can change this. We can change how much we contribute to Patreon. That's patreon.com/pmsutter, where if you want to build the exoplanet world of your dreams, you know where to go. And then after you've gone there, let me know because I would love to find that.

And then go to patreon.com/pmsutter where you can continue supporting this show, and I truly do appreciate it. We can change what these planets these simulated planets' atmospheres are made of. Are they thick? Are they thin? Do they have a lot of nitrogen?

Do they have water vapor in them already? Do they have carbon dioxide? Maybe some oxygen. What are they made of? This changes how a planet will evolve.

And there's all sorts of interesting little physics. It's not just about ocean currents, air circulation, landmasses, heating, and cooling off. There's all sorts of weird stuff that you can have heat from the mantle, from the interior of the planet keeping you warm. You can have a magnetic field doing its thing to protect against solar wind. You can have different kinds of rocks.

If you have plate tectonics, then you can efficiently remove carbon from the atmosphere. And if you don't have plate tectonics, you don't get to do that. It also depends on what the rocks are made of. Water vapor is super complicated. It is its own greenhouse gas.

It's very good at releasing and absorbing energy on its own. The the speed of the ocean currents and wind movements, the, like, the orbital distance of this planet doesn't just affect how much sunlight it receives. It it also affects how quickly this planet orbits around the star, and that sets up circulation patterns. This stuff is complex with lots of different variations. No two planets are alike.

So we want to find in general. If we try various combinations of planet characteristics, star properties, physics that we turn off and on, depending, like, maybe mantle heat is super important with these planets. Maybe it's not. We don't know. We try all these combinations, hope that they are at least somewhat plausible, and see if we get any combinations that are potentially habitable or if it's just a hard no across the board.

Here's what we got so far, and I could probably repeat this episode every year and get a better, more refined, more nuanced answer because that's how we make progress when we don't have a lot of data to go on. We don't have direct observations of these exoplanets, not yet at least. So in the meantime, we we have to make some guesses and some theoretical predictions. Oh, there are 2 kinds of potential habitability. One I'll talk about a lot and one I won't.

One kind is called the eyeball scenario, where just the dayside or the center of the dayside receives just the right amount of heat from its parent star to support a habitable region on that planet. Maybe there's some lovely liquid oceans and lakes and streams and jungles and whatnot on the day side, and then you just forget about the night side. That's one scenario. The other scenario is this terminator scenario or ribbon world scenario where the day side is too hot and the night side is too cold, but in between is just right. Notice that there is no real possibility of night side only habitability because in order to make the night side, the far side of a planet, warm enough, you have to basically melt the day side, which would mean the light side of the force winds, and you have atmospheric collapse because you just evaporate the entire atmosphere of the planet.

So there's really no scenarios that we take seriously. This is an example we can make a cut. Like, okay. If the night side of a planet, if we make it warm enough to support an atmosphere and liquid water, that means the day side is way too hot and we've lost. It is possible, we have found, to make a eyeball scenario where the day side is warm enough to support life while having a super frozen night side.

That's pretty cool. And then with these ribbon worlds, it gets a little bit more interesting where there's this precarious balance between the light forces and the dark forces. Here's the general picture for these ribbon worlds. The day side receives non stop radiation from the parent star. This can very, very easily lead to a runaway greenhouse effect.

Because if you're constantly receiving radiation, you're getting warm. If there's any ocean at all, if there's any water at all, that water will heat up. It will evaporate. It will turn into water vapor, which is a great greenhouse gas that will trap even more heat. You get no relief because you're under the sun constantly, and so you just trap more and more heat.

You go to a runaway greenhouse effect, and you end up boiling off your oceans and destroying your atmosphere. You you you get collapse. But for these ribbon worlds to work, you actually need to be right on the edge of runaway greenhouse collapse. Because if you're too cold on the day side, you know, runaway greenhouse effect, that's the that's the light side getting too powerful. But if you're too cool, if you're too far away from the right on the edge of a greenhouse collapse, a runaway greenhouse effect, if you're right, if you're too cold for that, if you're, like, fine.

Let's not go anywhere near runaway greenhouse effect. If you drop your temperature too much, then the night side, the dark forces win, it gets too cold, and all your atmosphere on that side gets frozen, and you collapse this planet. So in order to make a ribbon world work, you have to run your planet right up to the edge of a runaway greenhouse effect. And then to cancel out this runaway greenhouse effect, you have to move a ton of energy from the dayside to the nightside, and you have to ensure that the nightside is capable of efficiently dumping that energy out into space. You need to run the dayside super hot right on the edge of going haywire, and then you have to be able to take all that energy from the day side, pull it over to the night side where the night side acts like a radiator or something and just dumps that energy out into space, and then you can maybe maybe maybe get balance.

The amount of water on a planet like this, oceans, rivers, and vapor and such like, is really really important for these calculations. Water is exceptionally good at transporting heat much better than air, which is why you can get hypothermia even in mild temperature water. So you need water. You need water to heat up on the day side, flow over to the night side, and then cool off. But water also has a tendency to evaporate and to freeze, which means it can really, really easily and quickly trap or release sudden bursts of energy.

Like, on the day side, you might wanna just heat up your ocean and then have ocean currents pull it over to the night side. But if too much of that water evaporates, you get greenhouse effect. The light side wins. And similarly, on the night side, you want those ocean currents to cool off, you want them to radiate, but if they freeze too much, you get collapse. So it's all about balance.

Generally, the more water, the better because it gives the planet more options because it can more efficiently balance the light side and the dark side through transportation of heat. You just take a blob of water and move it over to the night side, and then it cools off. Also, changing the albedo, the reflectance. If you do get some freezing, you can change, like, on the terminator line. If you have some glaciers right on the terminator line, you can change how much that planet reflects the sunlight.

You have some options there. You can have cloud formation, which can reflect sunlight, which can transport heat. You get greenhouse intensity with different levels of water vapor. Water is good because it gives you lots of different ways to transport heat from the dayside to the night sign. In fact, water rich worlds, which are generally called aqua planets, and basically the Earth is an aqua planet, can become so good, so efficient at heat transport, that essentially the entire planet becomes habitable, with roughly the same temperature all throughout.

If you have a small rocky planet that is covered in a liquid water ocean, and it's orbiting super close to its parent star, you know, its year might last just a few days, the whole planet, if conditions are right, can be habitable, even the night side. Because water is so good at transferring energy that as soon as the day side heats up, which it it it's always doing because it's always 12 o'clock somewhere in that world. It's always heating up, but boom, you've got ocean currents, you've got water vapor, you've got cloud formation, you know, rain, like, a cloud forms on the day side, then it moves over to the night side, and it rains, it dumps its heat over there. It becomes so efficient that you could stand in the opposite end on the night side, a sky full of stars, never once seeing the light of the parent star, and it's pretty balmy. That's an aqua planet.

It seems, based on our simulations and what we can understand so far, that if the world is already water rich, then you can have a lot of options to achieve habitability. It's also possible, and emphasis on the word possible here, for planets without a lot of water, like less than 10% of their surface covered in water, to still be habitable. It depends on how efficiently the atmosphere can transfer heat, it depends on how this water is distributed across the planet, it depends on what all sorts of things like what the atmosphere is made of and the planetary composition, all the stuff I talked about just a little bit ago. But it is true, given some reasonable assumptions, and some not quite super simple models, there are a range of options where tidally locked planets, even those without a lot of water, can support life at the boundary between night and day. These would be the true ribbon worlds.

The dayside would be scorching hot, right at the edge of a greenhouse runaway effect, totally inhospitable. There would probably be land there. It would be the scorching depths of the Sahara just, like, totally inhospitable, perhaps even more so. Nothing could go in the extreme center of the dayside. And the night side would be full of glaciers.

It'd be like the Arctic, the Antarctic, poles, just glaciers, cold atmosphere, never ever seeing the sun. In between, balance between the light and dark forces, Where enough energy, just enough energy, is transferred from the dayside to the nightside that you don't get collapse. Now, we don't know how stable long term these scenarios are. It seems that if you have a water rich planet, an aqua planet, that you can be stable for a very long time. Just the mechanisms are in place, and you can get a lot of heat transport and keep it going for 1,000,000,000 of years maybe.

These planets, where life really is constricted to the ribbon world, remember the aqua planets are habitable pretty much across anywhere, dayside, nightside. These ribbon worlds would really just be habitable in a thin strip on that terminair line at the boundary between night and day. We don't know how how long term stable they would be. We do know it would be a wild place to live if you're standing there, if you're living there. It would be habitable, survivable.

The sun would be low on your horizon forever. It would never leave. It would always come from the same direction. Your shadow would never move over the course of a day because there is no day. It'd be permanent twilight.

You would constantly feel a wind coming from the direction of the sun and blowing to the night side. Always. The wind would always be there. In fact, the winds on these planets are probably far simpler than on the Earth because we don't have the rotation to deal with, so we don't get hurricanes. We don't get these big ocean gyres.

We just get streams, like jet streams of air moving from the dayside to the nightside constantly. Maybe the wind is blowing, like, a 100 miles an hour constantly coming from the direction of the sun and heading into darkness. If you venture too far into the sun and it rises higher and higher in your sky, you will you will die. You will run into an inhospitable desert. And if you go too far into the night, you will die.

You will run into impassable glaciers. But right there in between, at the balance between the forces of light and the forces of darkness, there might be a pathway for light. Again, this is hypothetical. It's speculative. We don't know for sure if our calculations are correct.

We are working on better calculations, more refined simulations. We are working on more direct observations of planets like Proxima b or the TRAPPIST-one system. There are a lot of options out there, a lot of variety of planets. If it turns out our calculations are wrong and ribbon worlds just can't support life, there's never a way to keep a stable atmosphere or liquid water, okay, then we keep cataloging these worlds, but know that these will not be a prime source for hunting for extraterrestrial life. But as long as there is a yes, even a maybe yes, because red dwarf stars are the most common kind of star in the galaxy, because tidally locked planets are also extremely common and perhaps the most common kind of planet, as long as there is a narrow window of possibility, a ribbon if you will, that life can thrive on these kinds of worlds, then we are obligated to keep looking.

Thank you to Sarah T, Michael w, and Aaron m for the questions that led to today's episode, and thank you so much to all of my Patreon supporters. That's patreon.com/pmsutter. I've got some names I wanna list off these wonderful contributors. These are all the people that pay $25 an up every single month. A lot of people signed up because they got a free copy of the book.

If you want a copy of my latest book, it's pmsutter.com/book. Pretty easy. But let me name these people. They deserve it. Justin g, Chris l, Lothian 53, Barbara k, Alberto m, Duncan m, Corey d, Stargazer, Robert b, Tom g, Nyla, Bike Santa, Sam r, John s, Joshua Scott m, Rob h, Luis m, John w, Alexis Gilbert m, Rob w, Valerie h, Demetrius j, Jules r, Mike g, Jim l, Scott j, David s, Angelo l, William w, Scott r, Dean c, Miguel, bbjj108, Barrelwires, Heather, Mike s, Michelle r, Pete h, Steve s, Nathan, and what what bird.

That's patreon.com/pmsutter. Keep those questions coming. I absolutely love it. Your curiosity knows no bounds, and that means this show will never end. I will see you next time for more complete knowledge of time and space.

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