Daniel and Kelly’s Extraordinary Universe - What if the Earth Stopped Spinning

Episode Date: October 29, 2020

What makes planets spin, and what would happen if they stopped? Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

This is an I-Heart podcast. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed. There's been a bombing at the TWA terminal. Just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, terrorism. Listen to the new season of Law and Order criminal justice system

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Listen to Culture raises us on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Why are TSA rules so confusing? You got a hood of you. I'll take it all! I'm Mani. I'm Noah. This is Devin. And we're best friends and journalists with a new podcast called No Such Thing, where we get to the bottom of questions like that. Why are you screaming?

I can't expect what to do. Now, if the rule was the same, go off on me. I deserve it. You know, lock him up. Listen to No Such Thing on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. No such thing. Hey, Jorge, do you ever think about how fast you're spinning? Oh, man, the way this year is going, I feel like my head's spinning.

That's for sure. Well, there's that, but there's also how the Earth is spinning around its axis, how we're all spinning around the sun, and how our entire solar system is spinning around the center of the galaxy. Are you going to spin us a tale about the physics of spin today, Daniel? I just think it's cool how everything in the universe seems to be spinning all the time. See, I knew you put a positive spin on it. Hi, I'm Horam, a cartoonist, and the creator of Ph.T. Comics.

Hi, I'm Daniel. I'm a particle physicist, and I can spin up or I can spin down. Does that officially make you a spin doctor? You are a doctor, and you sometimes do research quantum spin. So, technically, you do belong in a... 90s band with a one-hit wonder. Yeah, I don't know what's more believable, quantum spin or political spin. Sometimes it all seems made up. It's all not true, kind of.

True and not true at the same time. But welcome to our podcast, Daniel and Jorge Explain the Universe, a production of our Heart Radio. In which we examine all the amazing things about the universe. We spin them up, we spin them down. We turn them around in your head until they make sense to you. We think that wondering about the universe belongs to everybody, that your curiosity is the thing that drives science as much as the curiosity of scientists themselves.

And so we take a journey all around the universe and ask big and deep and important questions about how things work and try to give you answers that make sense. Yeah, because the universe is a pretty big place. And there's a lot to explore and a lot to ask questions about from the far reaches of the cosmos to our everyday lives and even what's happening right here on Earth. That's right. the physics that's literally under our feet has a big impact on how we live our lives and what's going on. Yeah, and we like to talk about not just kind of the what we know about the universe out

there, what scientists know, but also what they're asking about the universe, including what if questions. That's right. We like to let Jorge wander into the control panel of the universe and start flipping switches. What happens if you turn off quantum mechanics? What happens if you delete dark energy or dark matter. And this is not just some cartoonist idol speculation about the universe. This is an important way to do physics, to think about, could the universe have been different? What would it look like if we turned something off or something didn't happen? I feel like these are questions, Daniel, that supervillains have at their meetings in brainstorming sessions.

It's like, what if we turn off dark energy here on Earth? How can we spin that to our advantage? can we demand a $5 billion ransom for not turning off dark energy right build a laser on the moon I think actually that was the plot of one of those movies yeah it seems it seemed kind of quite now because I think in those

Austin Power movies he would ask for one billion dollars which nowadays you know considering things seems pretty small well if it helps people maybe they can imagine you doing this podcast from your underground volcano lair that's right with my pinky next to my mouth, stroking my cat or

meany version of me. But if it makes you nervous to imagine Jorge at the control panels of the universe, then instead, remember, these are just thought experiments. These are ways for us to imagine how the universe might be different and to wonder if it could be different. Yeah, because that's a big part of how science is actually done, right? Daniel, I mean, when you get together with your other physicist colleagues, do you sort of think about like,

what would happen if this happened or what would happen if this disappeared or what would happen if this stuff working? Yeah, absolutely. We are often reverse engineering the universe. We're imagining what are the possible different scenarios that are consistent with what we see. Because what we'd love to do is make some set of observations, some things we see about the universe that tell us uniquely how the universe has to be. But an important part of that is sort of creatively thinking, like, is there another explanation? nation. Is there something else that could have happened that explains what we see? And so you

have to go through these thought experiments. You have to imagine what if there was no dark energy or what if the sun turns into a black hole or how do we know that there isn't another planet out there? You have to imagine all those other crazy scenarios before you can dismiss them. And sometimes they lead to crazy discoveries because they turn out to actually be true. Yeah, because you know, thought experiments are a lot cheaper than actual experiments, right? They don't cause billions of dollars. Just a few billion neurons. I still ask for billions of dollars for my thought experiments, but yeah, they don't go to building experiments. They just go to funding my elaborate volcano layer. Inside of your head. Inside of my head. That's right. Yeah, so today

we'll be asking a question that it's pretty impactful. I mean, it sort of affects everyone's lives on a daily basis. And in fact, it sort of defines a day for us. That's right. It's all about what's going on under our feet. It's about how our world is moving and where it's going. Yeah. So we like to stay grounded in this podcast. So today on the podcast, we'll be asking the question, what if the earth stop spinning? Now, Jorge, in your super villain brainstorming meeting, are you imagining suddenly stopping the earth or sort of like gradually stopping it and turning it the other direction? I guess if I was a super villain, I would be aimed for maximal damage, like the worst case scenario.

So whichever one of those would give me the most ransom money, I guess, as a supervillain, that's optimal, right? I don't know. There's a delicate balance there. If you're blackmailing or extorting something, you want them to stay alive so they can continue to fund you in the future, right? You don't want to obliterate your crime victims. You want to slurp some money out of them, but keep them functioning.

I see. If you were a supervillain, you would go for the subscription model, not the one. one-time payment. You're more like the free-to-play type of game. That's right, because those victims never remember to cancel their orders, and you just keep billing their credit cards month after month. Oh, man. That would make a pretty good plot for a movie.

Anyway, so, yeah, that's a pretty interesting question. Daniel, how did you come up with this question? This is a question that a bunch of readers wrote in and asked us. It's something people think about, and it tells you that it's not just physicists out there, that wonder about things in the universe is also everybody and maybe some of our listeners are potential future supervillains.

I hope not because then we'd be enabling them in some way Daniel. But also, you know, a lot of our listeners are physicists and in fact, isn't everybody a physicist in a certain way? Yes, exactly. If you're the kind of person who does this kind of thinking who thinks

maybe the universe could be like this, what would happen if that happened? Then you're doing physics and that makes you a certified physicist. Boom, Daniel will give you a PhD. Just right in to PhDs for free at Daniel and Horace. Yes, welcome to your PhD in Internet Physics. Yeah, so it seems to be a question that a lot of people are having out there. I guess where does that come from, Daniel?

Does it feel like, you know, it's something so normal and something that we're so used to that, you know, it's very curious to think about what would happen if it stopped? Yeah, I think that there's a lot of times in the history of science when we realized that something we thought was like bedrock truth was fundamental to our universe turned out to not be true. And so that gives you this instinct to question everything, to wonder, why is this happening? What would it be like if it stopped happening?

And so I think that's where the instinct comes from, just to look around and ask questions about the basic nature of our reality. And I wonder how many people who are wondering this question think something good would happen? as opposed to something not good. I don't think anybody imagines, ooh, I have a great idea. Let's stop the earth from spitting

because it really annoys me how we have daytime. The vampire lobby might be in on that. Or maybe it's, you know, cartoonist late for their deadline and wondering, like, could I eke out a few more hours of late-night effectiveness if I somehow stopped the earth? That seems like a lot more work

than actually doing the thing. Well, that's the lesson of procrastination, isn't it? And you remember, Superman did this once. Something happened he didn't like. And so he turned the earth the other direction, somehow reversing the flow of time to undo the death of Lois Lane. What did your physics sense tell you when you watched that movie? Did it freak out?

I think I was like a seven-year-old physicist when I first watched that movie. And I thought, huh? How could Earth itself control the flow? of time, that's ridiculous. Do you think, well, gosh, I feel like we get into a whole episode about the Superman movies. Do you think he, or Superman in general, do you think he spun the earth the other way? Or do you think he went back in time himself? Well, that's the other explanation for that scene.

I see. You're imagining he's going faster than the speed of light, and so somehow he goes back in time. Yeah. Yeah, perhaps. But doesn't he, isn't he pushing on the earth? Disney actually spinning it the other direction, I have to go back and review that scene. No, no, he just flies over it. Oh, he just flies over there.

Somehow that makes the earth spin the other way. But maybe it was just, he was just going back in time. I see, yeah. Well, you know my feelings about time travel and fiction. It's all gibberish. I thought you were going to say Superman, but I guess you were more specific. But anyways, we're wondering how many people out there had thought about this question or even have a possible answer to it.

So as usual, Daniel went out there into the internet and asked folks to send in their answers. That's right. And thank you to the listeners who volunteered to answer questions without any research just from the top of their head. If you'd like to offer answers to tricky topics without any preparation, please write to us to questions at danielanhorpe.com. So think about it for a second.

What do you think would happen if to earth stop spinning? Here's what people had to say. Yeah, I'm not sure what controls your spin perhaps has something related to the distance to the sun and as well, the moon and maybe the gravity of other objects. Also could be that the flow of the inner core, all the molten metal in the inside,

maybe play a role. I don't know, I have no clue. And I guess it might be decreasing in speed I don't see why would it be increasing but also that would mean then in any way the days are becoming either shorter or longer somehow but so far I haven't seen that this is an issue but I guess it should be in a very small scale what controls the earth spin is it slowing down the earth the earth was born and this is the way the earth was born spinning I don't know exactly what control probably the core controls the

spinning and I think it's slowing down but I don't know by how much on the top of my head I can't really think of any factors that would cause the earth to spin around an axis so I'm guessing that when it was formed when the earth was formed when the earth was formed. The matter was spinning and it's just sort of kept on going. So I would say yes, it's probably slowing down. And I know that other planets also spin, but I think they're quite different speeds. So I'm guessing it's not anything to do with their size. So yeah, my guess would be that it's just kept on spinning since it was formed and nothing's stopping it is just friction. But as far as why it rotates at the speed it does, about the north and south pole, I'm not sure why.

I'm not sure what caused it. I did hear a long time ago that it's slowing down. I'm sure the Earth received all of its spin in its primordial creation. And if it were a rigid body, a piece of rock, then it would keep spinning with the same angular momentum forever. but the earth is not a rigid body. It has a fluid core and a fluid core is subject to convection and other movements and forces

and therefore it must be losing some of the spin to friction and heat. And by the second law of thermodynamics I suppose it must be losing spin rather than acquiring spin. Whether this is a big effect or not, I'm not sure.

I think the conservation of angular momentum is probably the reason why the Earth is still spinning. Well, it is slowing down and it is being slowed down by the tidal forces from the moon and also

the sun. Of course, all other planets too probably, but their effect is negligible. I think we add lip seconds because of that. All right. I feel like these answers reveal a lot about our audience Daniel, all of them sort of try to get down to the, to a reason why the earth would stop.

Yeah, exactly. You have to wonder what's controlling the earth's spin. You can't just be like, I'm just going to turn it off. You can't just like wander into the control room of the universe and flip a switch, right? You got to follow the rules. Right. And nobody said super villain or Jorge flipping switches. Were you relieved? Were you worried you were going to be blamed here? I feel like I get blamed for a lot of things that I'm not actually responsible for but yeah a lot of interesting answers here though a lot of them talk about the origin of the earth spin and the future of the earth spin and so that's that's pretty fascinating stuff all right so let's dive into it daniel um i guess maybe maybe a very basic question just to take

a step back is to talk about why the earth is spinning in the first place right like we're so used to it turning around and giving us daytime and night time. But, you know, maybe a lot of people haven't thought about why it is actually doing that. I mean, it's possible that it could not have been, right? I guess it's possible, but you know, the amazing thing about spin is when you look out into the universe, essentially everything is spinning. I mean, the sun is spinning, all the planets are spinning around their axes and then spinning around the sun and our solar system is spinning around the galaxy. And so spin is a pretty big part of existing in the universe. It's really kind of fascinating. I guess it's sort of like motion in general, right? Like in space,

there's no very little friction. So if you're moving, you're going to keep moving or if you're spinning, you're going to keep spinning. Yeah, exactly. There's this conservation of spin. We call a conservation of angular momentum, which really just means like motion around some axis, revolving around some axis, spinning. And we have this conservation of angular momentum in our universe. And we talked recently on the podcast about fundamental symmetries. Conservation of angular momentum comes because there's no preferred direction in space. And so you can translate that rotational symmetry of the universe into this conservation of angular momentum, but it has a real practical consequence. It means that if something starts spinning, it will continue spinning. Right. And so you might

ask then, like, why is the solar system spinning? Why is the earth spinning? It's spinning because the stuff it was made out of was spinning. And I guess maybe the question is, why is the stuff that it started with spinning in the first place? I mean, in the big bang, are you saying the big bang things were spinning? Yeah, that's a really fun question. It comes down to like how stuff gets broken up into chunks. Imagine like a big swirling hot plasma, right? There's definitely motion in there. If you then break those things up into pieces, you can ask, like, is one of those chunks spinning? Like, one of those chunks is destined to be our galaxy or our solar system or our planet. And if you take all the motion of all those particles, it's either

going to be spinning clockwise or spinning counterclockwise or perfectly somehow balanced so that there's no spin. And so if all those outcomes, it's much more likely for it to be randomly spinning in one direction or the other, then for it to be perfectly balanced. Right. But when you're talking about like the spin of a lot of things, you actually sort of mean like the overall direction of where each thing is going. You don't mean like each thing is spinning and so overall everything has a spin, right? You mean sort of like, you know, if things have a velocity sort of relative to the center,

then that's sort of considered spin. Yeah, exactly. It's the motion of the object. So you can, for example, draw a line through it and say, all right, here's the thing I'm going to measure my spin around. And then you could ask, how are things moving relative to that? And things that are moving in one direction will give you clockwise spin, and things that are moving the other direction will give you counterclockwise spin. So you've got to add all those up and that you can get overall motion. And it's either that it's all balanced, so there's like weirdly no spin, or that things tend to be going more in one direction than the other.

And if you just take like a random scoop of hot plasma from the early universe, it's got a lot of motion in it. So for that motion to like add up to zero spin would be pretty unusual. It's much more likely for all those things to be moving an direction, which adds up to some kind of spin. Right. And then it, and then I think it's, isn't it kind of like part of the way the physics work that if you just leave that system over time, it's going to eventually turn into a spinning disk. like everything's going to start spinning over around one axis and everything's going to sort of stop spinning the other ways. Yeah, and that's a fascinating consequence of living in three dimensions, because in three

dimensions, you can always pick one axis for the spin. You can always say, here's my axis, I'm going to measure my spin around this axis, and that's the overall axis around which you have spin. And then gravity can coalesce everything around that axis. Things keep spinning, right? they keep going. But along that axis, there's nothing to prevent gravity from flattening things, from things pulling down. So in the three dimensions of our space, you can always pick one axis where all the spin cancels except along that axis. If we lived in four-dimensional space,

then there would be two axes you could pick where the spin wouldn't cancel. So we live in a three-dimensional universe. So there's always like one axis you can find where the spin cancels in two out of the three dimensions, but not around that axis. That's why galaxies and solar systems are disks, because gravity squishes things down along that axis, but not around that axis. Right, because it sort of balances it out in one direction, but then it does tend to flatten things in the other direction. Yeah, and this angular momentum is the reason why, for example, the Earth doesn't collapse into the Sun, right? It's the reason why we're still here. If we didn't have angular momentum, then the Earth would just fall into the Sun because of the force of gravity.

It's the angular momentum that keeps us in an orbit that keeps the planets from just collapsing into the sun and keeps the galaxy from collapsing into the central black hole. So angular momentum is very much why we are here. Yeah. And it sort of works at different scales, too, like you said. Like, you know, the galaxy looks like a disk because everything's spinning on sort of one flat plane. But then the stuff within that plane also sort of collect. and the same thing happens and that starts spinning in one plane like the solar system.

And then also the stuff in the solar system starts coming together due to gravity like the Earth. And then that's also spinning in pretty much almost the same direction, right? Yeah, exactly. The Earth spins in the same direction as the planets move around the Sun and the planets move around the Sun in the same direction as the Sun rotates. Now, that's mostly true for everything. And we'll talk about it in a minute.

There's sometimes some deviations. Those deviations are really fascinating because they tell you like something weird happened here. For example, most of the stars in the galaxy rotate around the center of the galaxy in the same direction. But there are a few things out there that are going the opposite way that rotate around the center of the galaxy going the other direction from most of the traffic. I think they're called contrarian stars. No, they're not. No, exactly. These are actually globular clusters, these like collections of stars.

And as we'll talk about it a minute, there are some planets in our solar system that spin in an unusual direction. And so you can ask questions like, if everything else is spinning this way, why is this spinning the other way? So spin is really fundamental to the whole like structure of the universe and the structure of our galaxy. And it reveals lots of interesting clues about how things came to be. All right, let's get into how the other planets in our

our solar system spin, and what would happen if our planet stop spinning? But first, let's take a quick break. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene.

In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism. Law and order, criminal justice system is back. In season two, we're turning our focus to a threat that has happened. in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota,

it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, My boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now, hold up. Isn't that against school policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor, and they're the same age.

And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his person? professor or not. To hear the explosive finale, listen to the OK Storytime podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I'm Dr. Scott Barry Kaufman, host of the psychology podcast. Here's a clip from an upcoming conversation about exploring human potential.

I was going to schools to try to teach kids these skills, and I get eye rolling from teachers or I get students who would be like, it's easier to punch someone in the face. When you think about emotion regulation, like you're not going to choose and adapt to strategy which is more effortful to use unless you think there's a good outcome as a result of it if it's going to be beneficial to you because it's easy to say like like go you go blank yourself right it's easy it's easy to just drink the extra beer it's easy to ignore to suppress seeing a colleague who's bothering you and just like walk the other way avoidance is easier ignoring is easier denial is easier drinking is easier yelling screaming is easy complex problem solving

meditating, you know, takes effort. Listen to the psychology podcast on the IHartRadio app, Apple Podcasts, or wherever you get your podcasts. All right, Daniel, we are spinning here. We're in a spin class. And some people might be listening to this while on a stationary bicycle spinning. but um but we're talking about give them some motivation then you know push push push let's do the opposite let's encourage him to take a break chill chill chill just relax why are you why are you bicycling so hard eat a donut you look great man don't worry about it think about

the spinning donut all right so we're talking about spinning things in in space and in our solar system and then you were saying that not all planets spin the same way yeah there's huge variation, not just in the direction of the spin, but in the rate of spin. Like, the Earth, of course, takes one day to spin. That's how we define a day. And it turns out that Mars also takes about a day to spin. But the bigger planets like Jupiter and Saturn, they spin much faster. Like, it only takes Jupiter nine hours to spin.

And it's a lot bigger, which means its surface is really going quickly. Do they measure that by, like, the surface? Or, like, do we know how fast does the core? is spinning. We think actually there's differential rotation in some of these planets that the core might be spinning at different speeds than the outer layers. But here we're talking about the outer layers. We're like watching stuff on the surface of the planet move. All right. So they're spinning really quickly, but there are some planets that spin really slowly. Yeah. Mercury and Venus, the ones that are closer to the sun than us, they spin really slowly. Like Mercury takes 58 days to rotate

once. And Venus takes 243 days, which is ridiculous. Yeah, that is weird. And now, is there an explanation why some of them spin faster than others? So we don't really know, but we think that some of these things reflect like the history of the objects, like maybe they got hit and that changes their spin. And also it reflects something about the effect of the sun on these objects. Right, because the ones that seem closer to the sun seem to be spinning slower, whereas the ones further out are spinning super fast. Yeah, because the sun actually plays a big effect on the spin of these planets. It's not just like the original stuff that was spinning and is still spinning. The sun is massaging these

planets. There are gravitational tides on these planets. So the sun pulls harder on the bits of the planets that are closer to the sun and not as hard on the other side of the planet that's further from the sun. And so that affects the shape of the planet. It causes these tides, these squeezing of the planet, and that affects its spin. But it also has another opposite effect in that it heats up the air on the planet. So it heats up the air on one side more than on the other side, and that causes really complex atmospheric tides on the planet. Like the shape of the Earth's atmosphere changes as we go around the sun.

And that can actually change the rotation of the planet? Yeah, differential heating of the atmosphere can cause. like a shape difference on the planet and it can cause differential drag on the planet and so these two things it's very complicated and people still don't even really agree on how this is all working there are complex models but for example we think that the reason that venus rotates so slowly is that this is some sort of like balance between these gravitational effects and these atmospheric effects that's come to balance venus in this weird state all right and so it's not just how fast they're spinning that is different between the planets it's also

So, like, how they're spinning, right? In which direction they're spinning? Yeah, because one of them out there is totally crazy. Like Uranus is tilted 90 degrees. Most of the planets are spinning around an axis that's parallel to the axis that the sun is spinning in, right? The sun is like the major player here and everybody's following its lead. But Uranus, it spins around an axis that's tilted like 90 degrees. It's spinning around an axis that's like flat with the solar system.

It's like laying down. decided to take an app. It's doing its own thing. That's fascinating because you wonder like, well, what does that mean? Where did that come from? Why is that happening? And the typical story is that, oh, maybe Uranus was like hit by some really big object. Because to change the spin, you need some sort of external force, right?

An object that's just spinning can't change its spin without some sort of external torque, something that's going to change its angular momentum. So you imagine like some object coming from deep space and smacking into it. and changing its spin. And that's a possible explanation, but scientists don't actually think that's the most likely explanation. I see.

The idea is that they all started spinning the same way, like all the planets were spinning in the same direction, but if it's not, then something must have happened. Something must have happened, yeah. And the problem with the story that it's like one really big collision that smacked Uranus and knocked it over, Uranus seems to have kept its moons. If there was one really big collision

that was big enough to knock your, over really suddenly, then it probably would have lost its moons, would have just gone flying out into space. Instead, to keep your moons and tilt over, you need some sort of like gradual process. So they're imagining now some sort of like series of smaller collisions that like knock it a little bit and knock it a little bit, knock it a little bit, doing it gradually so you don't lose the moons. Interesting.

Now, are the moons spinning in the same way that the planet is spinning or is it totally different? most of the moons do spin the same direction the planets are spinning and the same direction the planets are going around the sun but not all of them and there's too many moons in the solar system to even count for and these big planets have lots of moons and so there's definitely some crazy behavior there too many moons i like that phrase

and uh some there's one planet that even rotates backwards like it spins the wrong way yeah that's venus venus is going the other direction you know like first of all it's bonkers that Venus takes so long to rotate, you know, it takes 240-something days to rotate, which is about as long as it takes for it to go around the sun, which means that, like, a day on Venus is about the same as a year on Venus, which means, like, you know, it's always your birthday on Venus or always your anniversary if you live on Venus. Nice.

That's a lot of birthday gifts you have to buy. But you have all day to plan it, right? Which turns out to be a year. It's one long party in Venus. It is one long party. But yeah, it's going the other direction, right? It's spinning the opposite direction from its motion around the sun. All right.

So it seems that most things are spinning in the solar system. But now to get back to our question is, what would happen if the Earth stopped spinning? What would happen if we weren't spinning the way we are now? This is not something I recommend. you actually exploring Supervillain Council because this would be pretty bad. And it depends a little bit on what you mean by the Earth stop spinning.

Like, is it just the rock of the Earth that stops spinning all of a sudden? Or is the whole planet including like the oceans and the atmosphere also stops spinning? Right. And it also depends on how fast it stops spinning, right? Like, are we hitting the brakes? Is Superman suddenly like putting his thumb

on the Earth and making it stop? Or are we talking about like over centuries or even years? Yeah, exactly. So the most dramatic scenario is like if the earth stopped spinning basically immediately, Superman pulls the brakes and he only does so on like the surface of the earth and its internals. In that case, you have some pretty dramatic effects because now the air is moving at a really high velocity relative to the ground. Before you stop the spinning, the ground and the air are both rotating around the sense. center of the earth. But if the earth stops, then all of a sudden the atmosphere is moving across

the earth instead of just sitting on it and at pretty high speeds. Right. Yeah, like if you stop the rock of the earth, everything on it would still keep on spinning. That's the problem, including the, I guess, starting with the atmosphere, but also us. Exactly. Also us. And it depends on where you are on the earth. If you're at the equator, then the spinning of the earth moves you a whole circumference to the earth like 24,000 miles in 24 hours, that means you're going at 1,000 miles per hour. And if all of a sudden, the rock under you stops, then basically you're moving at 1,000 miles per hour relative to that rock.

That doesn't sound good. Basically, yeah, it'd be like being in a crash, kind of. You get launched in the direction of the spin. You would get launched in the direction of the spin and you would smack right into stuff around you, right? And so it'd be pretty dangerous. The world around us is not built for humans traveling through it at a thousand miles per hour. Right. And, you know, like the houses would stay attached to a rock, presumably, or maybe not actually, but most of the stuff would stay attached to the rock, but then the wind would be basically going at a thousand miles per hour.

Yeah, my house is not strong enough to sustain a thousand mile per hour shock, but maybe yours is. But if you imagine that your house somehow does stay attached to the earth, then it's suddenly moving through the atmosphere at a thousand miles per hour. And a thousand miles per hour is a very strong wind, stronger than any hurricane. And it would basically just scour the earth smooth. At the equator, though. Only at the equator. Yes, at the equator. If you're at the north pole, then there's no wind, right?

Because at the north pole, you're not moving across the surface of the earth. You're spinning like, you know, atop. but if that stopped, there'd be no relative velocity to the air. What if I'm pretty far up north, like Norway or Canada? Do I have some good chances of survival there, there, or is it still pretty dramatic? Depends a little bit on how dependent you are in the rest of the Earth's economy. But, you know, I think the global devastation would be such that, like, society would collapse. You might immediately survive, you know, goes up, like, with some trig function of your latitude.

So Norway would definitely be more survivable than, you know, Equatorial Guinea. All right. So that's if the Earth suddenly stopped spinning. What else would happen? What if it wasn't sudden? I think it's much more interesting to consider like an actual physical scenario where the Earth stops spinning more gradually and to think about like what would life be like on an Earth that has like very gradually come to a screeching halt and not spinning.

I see. Where everything in it survives? technically, nothing gets destroyed immediately. Now what would life on Earth be like if we weren't spinning? Yeah. And there's some pretty interesting effects. Like, well, first is the obvious stuff. Like, well, there's no more day and night, right?

Your vision of the sun seeing it only 12 hours a day is because the Earth is spinning and it turns the sun behind the back of the Earth. But if the Earth is no longer spinning, then your days are not 12 hours. hours long, they're like six months long. Now, would that affect, like, temperatures? Like, would one side of the earth get roasted if it had a six-month day? And the other side would get frozen? Yeah, absolutely.

It's like having summer, but without a break, right? In the summer, it can get pretty hot because you're tilted towards the sun. But then you get a break when the earth rotates and you get nighttime for things to cool off. But in this scenario where the earth doesn't spin, you have, like, six months continuously of hot summer days. And so the temperature variations would be much more dramatic than they are now. So the seasons would get exaggerated.

Right. But would it get too hot for us to live in? Like would it just roast everything on the daytime side of the earth? Or would it just be like a long day and we would be okay? We just had to wear more sunblock. Well, on average, the same amount of energy would fall in the, Earth's surface. So you'd have colder winters and warmer summers. And so the peak temperatures would definitely be more extreme because it would be time for the temperature to build up day upon day

upon day. But you're not going to be like roasting humans when they go outside. It's just going to get more uncomfortable. And there will be portions of the Earth that may be unhabitable because they get too hot, practically speaking. Right. And I guess the biology would have to adapt too. Like plants would have to get used to only getting sun six months of the year. Yeah, it's incredible. how much of our ecosystems and how much of the biology on Earth is linked to this cycle of day and night. It tells you not only that it would be devastating that it stopped, but that it's been going on for a long, long time. You know, so much of life on Earth depends on this cycle, assumes this cycle,

which means it's probably never really been disrupted. Yeah, I guess what would happen? Would you need, like, would all the plants die six months of the year and then come back the other six months? Or would they just, do you think they would just adapt? Well, there are some plants, right, that do die every six months and just go back to their roots and then regrow. And so plants that can do that would survive. So, yeah, plants that need sun, you know, more than every six months would definitely die off. And we'd be left with a subset of plants that can survive this kind of weird environment.

And then they would, you know, evolve and grow to fill all those niches. So we'd have very different foliage on earth. If you stop the earth from spinning and then waited like a thousand years, you'd have a very different collection of plants. Some of them for sure would survive. Well, I certainly would look forward to not having to work six months out of the year. That sounds pretty good. Like being able to just taking for six months. That sounds pretty good right now.

But you might have to plan your vacations differently because the whole surface of the earth would look different if the earth wasn't spinning. Yeah. What do you mean? Like the continents would be different? Yeah, the continents would be different because the distribution of water would be different. water responds differently than land does to spin. Water is liquid, of course. It's much more deformable.

And so as you spin the earth, the water tends to bulge up near the equator. And so it's the spinning of the earth that keeps more water at the equator than at the poles. And if the earth stops spinning, then that water sort of resettles. And a lot of it moves from the equator out to the poles. What? So wait, are you saying that the water is deeper or taller? near the equator than near the poles? Distance from sea level to the center of the earth

is greater at the equator than it is at the poles. And so if you stopped spinning of the earth, that, of course, would equilibrate. And so a lot of water would flow to the poles. And what you get is basically two massive polar oceans, right? Huge, vast oceans near the poles and then like a big supercontinent at the equator. Whoa.

Meaning, forget about Norway. then in Canada, maybe. Like, they may have survived. The Earth, stop Earth hitting the brakes, but they're not going to survive the floods, maybe. Yeah, exactly. North Dakota now becomes, you know, ocean front property. Oh, and Panama becomes much bigger.

That's good. Exactly. Exactly. Panama becomes much bigger. Wow. So it would reshape the map. It would totally reshape the map. Exactly.

You know, when you look at the surface of the Earth, what you're seeing only, of course, is the land that peaks above the surface of the water. It's if you change the water level, you're going to change the edges of the continent since you're going to change really what the Earth looks like. So are there numbers for that? Like how much would the sea level change at the equator?

Is it like hundreds of feet or several feet? Well, the distance from the center of the Earth to sea level is 20 kilometers greater at the equator than at the poles. So it would definitely make a dramatic effect. All right. let's get into some other fond consequences of the Earth's stopping its spin and what might actually make it stop. But first, let's take another quick break.

December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys, Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal, glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism.

Law and order, criminal justice system is, Back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Oh, wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school. week on the OK Story Time podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone.

Now, hold up. Isn't that against school policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor, and they're the same age. And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them

both the meets. So do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast on the Iheart Radio app, Apple Podcasts, or wherever you get your podcast. I'm Dr. Scott Barry Kaufman, host of the psychology podcast. Here's a clip from an upcoming conversation about exploring human potential. I was going to schools to try to teach kids these skills and I get eye rolling from teachers or I get students who would be like, it's easier to punch someone in the face. When you think about, emotion regulation, like, you're not going to choose an adaptive strategy, which is more effortful to use unless you think there's a good outcome as a result of it, if it's going to be

beneficial to you. Because it's easy to say, like, go you, go blank yourself, right? It's easy. It's easy to just drink the extra beer. It's easy to ignore, to suppress, seeing a colleague who's bothering you and just, like, walk the other way. Avoidance is easier. Ignoring is easier, denial is easier, drinking is easier, yelling, screaming is easy. Complex problem solving, meditating, you know, takes effort. Listen to the psychology podcast on the IHartRadio app, Apple Podcasts, or wherever you get your podcasts. All right, Dinah, we're talking about the Earth stopping. It's spin. And so far, it's not good. I mean, longer naps, perhaps, you know, a new beachfront property

in North Dakota. But overall, it doesn't sound good. And that's not even the worst that can happen. That's not even the worst, exactly. The worst maybe is that you would all gain weight if the earth stopped spinning. That's the worst. Well, it depends on your personal priorities. But, you know, part of your weight is the Earth's gravity pulling down on you, but there's a counteracting force there. The spin of the earth helps gently push you away from the center of the earth, the same way that like the Earth's motion around the sun is what prevents it from falling into the sun. There's this centripetal force that pushes in the opposite direction. And the Earth's spin contributes to that. So if the Earth stops

spinning, then it would only be the force of gravity and you would feel it more. There'd be no counteracting force there. Wait, what? Are you saying that I weigh more in Panama than I do at the North Pole? No, I weigh less in Panama than I do in the North Pole. I weigh more in the North Pole. Yeah, that's right, because you are feeling the Earth spin more in Panama than you are at the North Pole.

So that's why you gain weight every time you go to Norway, right? It's not just the snacks. It's not just the colt fish and blubber. They keep feeding me there. Yeah, exactly. And if you did the opposite, if you spun the Earth faster, if you convinced Superman to spin the Earth much, much faster, if you got it to spin 18 times faster, so that it only took like an hour and a half for the Earth to spin all the way around, then you would be weightless on the surface of the Earth. We wouldn't just stop spinning. We might even lose our magnetic field.

Yeah. If you stop the Earth from spinning, you would really play unpleasant games with what's going on inside the Earth. We talked a minute ago about how some of the planets have differential rotation. like parts of them are rotating at different speeds. That's actually kind of key, because that might be what helps drive the magnetic field of the Earth. Remember, magnetic fields come from things moving in circles, usually like currents of charge,

or in this case, hot lava, or melted metals that are flowing in these big currents inside the Earth. And we think that the magnetic field might come from the fact that those currents don't flow at the same speed as the Earth. But it's vital that those things are spinning, and if the Earth stopped spinning, it might slow or change that rotation. Oh, but it might not too, right?

Like maybe we could stop spinning, but the stuff inside of the earth could keep churning. It could, right? It depends on what Superman's doing. If he's only pushing on the crust, right, and he lets the stuff inside keep spinning, but if he's got some like power to stop everything inside the earth from spinning,

if you like froze the earth so that nothing in it was moving and it wasn't spinning, then you would kill the magnetic fields, absolutely. And then we'd be toast. And then we'd be toast, yeah, because our magnetic field is really important. It's literally a force field that protects us from solar radiation. The sun is constantly shooting out an enormous stream of protons and electrons and other crazy stuff and bombarding us with it. And the magnetic field deflects all that stuff.

Yeah. All right. So it doesn't sound great. Let's hope we keep on spinning. Let's pay the ransom to the supervillain if they actually do the third. threaten to stop the Earth from 20. Yeah, I mean, a billion dollars sounds like a good value there. Yeah, everybody puts in 20 cents and hey, we can save the planet, right?

Yeah, there you go. Now, what are some of the things that might actually make the Earth stop? Could this actually happen? I mean, of course, Superman is not going to come and stop the Earth because, first of all, he's a good guy. And second of all, he doesn't exist. But is this a realistic scenario at all? Like, could the Earth stop spinning one day, eventually, maybe?

maybe eventually and if we look on really long time scales we do see that there are some processes there that are changing the way the earth spins so for example we have a moon that's rotating around the earth and those two things are not separate the moon is exerting a gravitational force on the earth just like the earth exerts a force on the moon and that causes some weird friction like the moon is squeezing the earth and that changes the shape of the oceans and that causes some friction with the surface of the earth. And so what's happening is that the moon is sort of stealing some of our rotational speed by doing this.

And it means that the moon is getting further and further out. So we're losing the moon, about a centimeter per year is getting further and further away. And to compensate for that, to conserve angular momentum, the earth is slowing down. Whoa. Meaning like a, like we're losing energy to the moon. Yeah, we're losing energy to the moon. It's called tidal friction. It's not happening very fast.

It's like every century, a day is two milliseconds longer. In one century, in a hundred years, it'll take two more milliseconds for the Earth to complete one rotation. So it's not something that's really going to change your life or my life or our kids' lives. I haven't been feeling a little more sluggish as I get older, Daniel. Could that be part of the effect of the moon? Yeah, I think you're slowing down the rotation of the Earth. But it means that, like, in 140 million years, our days will be 25 hours instead of 24 hours.

Wow. So you'll get that extra hour to get all your stuff done. Wow. Two milliseconds, that could make a big difference. It really adds up. So that's a real thing that's happening and is gradually slowing down the spin of the earth. And so, you know, 140 million years, you slow down by an hour. After a billion years, you slow down by 10 hours or something.

so or eight hours after that it doesn't really make sense to make predictions because at that point the sun is going to expand and absorb the earth anyway and so it doesn't really matter how fast we're spinning at that point it's going to be sunlight 24 hours no matter or 26 hours no matter what that's right but there are also other things that are happening here on earth that are changing the rate of the earth spin like uh like in real time like real time it turns out that if you just move stuff around on the earth you shift a chunks of earth around, you can change how fast the earth is spinning. Sort of like a figure skater on the ice, if she pulls her arms in, she spins faster.

If she moves her arms out, she spins more slowly. So if you rearrange chunks of earth, you can have the same effect. And this kind of stuff happens every time there's like a really big earthquake. Yeah, it happened recently, right? Like the Japan quake. Yeah, the 2011 quake in Japan moved enough earth towards the equator that it sped up our rotation by 1.8 microseconds. Wow. Because the Earth got less spread out or more spread out? Yeah, so to speed up something that's rotating, you need to move stuff closer to the axis of rotation

so that it would have to spin faster to have the same angular momentum. So I guess this means that it moved a bunch of Earth closer to the poles, which I guess would mean moving it away from the equator, actually. Wow. So does that mean, Daniel, that if everyone on Earth suddenly lay down at the same time, would that make the Earth spin faster? Or if we all jumped up at the same time, would that make the Earth slow down for a second? Yeah, actually, I think the Earth would spin faster if everybody would lay down or if everybody like went underground into the subway. Or if everyone went to the equator, right?

Yeah. If everyone went to the equator, that would slow the Earth down. Wow. Let's do it, Daniel. Let's start a movement. Jorge's paying for everybody to go to Panama. Make the day longer. It's all moved to Panama.

There you go. And at the same time, there are effects from the sun. Like the sun is having these tidal effects on Mercury and Venus, but we're also pretty close to the sun. And so the sun is sort of trying to do to us what we are doing to the moon. Remember that the rotation of the moon is not free. It's not just like doing whatever it likes. It's locked to the Earth because of these tidal forces.

Earth is like squeeze the moon. moon a little bit and it's tugging on the part of the moon that's closer to it so it keeps the moon from rotating freely which is why we always see one side of the moon when we look up well the sun is trying to do the same thing to us it's trying to lock the earth's rotation tugging on it so that the same surface always faces the sun and so if that happens far far in the future that would mean something crazy that would mean not just that the earth stops spinning but if there's like a dark side of the earth and a light side of the earth all right so it's It doesn't sound like it's happening anytime soon, Daniel. It's not something we have to worry about any time soon. Barring a Superman and maybe like a meteor hitting us, but then we'd have other things to worry about that. Yeah.

If there's some massive collision with enough energy to, like, hit the Earth and stop it spinning, then we're anyway going to get devastated and our atmosphere is going to be roasted. So the fact that our destroyed corpse of a planet is no longer spinning afterwards, it's not really going to be the issue. It's a leisure of our problems. how long our day is. All right, well, it's still it's sort of interesting to think about

you know, kind of what we take for granted. You know, the earth spinning. You know, we always think that there's going to be a tomorrow. But that's not necessarily true. No, exactly. And this kind of thing, the earth spinning, it's not necessarily something that's going to last forever. And it's sort of an artifact.

It just sort of depends on the original chunk of stuff that became the earth, how fast it was spinning. we could have lived on a planet with a 12-hour day or a 36-hour day. The 24 hours is not fundamental. It's really quite accidental. Yeah, so it sort of really makes you appreciate not just the day, but the idea of a day. All right. Well, we hope you enjoyed that.

Hope it got you to think a little bit about your place in the world and what's happening right underneath your feet. Thanks for joining us. See you next time. Thanks for listening and remember that Daniel and Jorge Explain the Universe is a production of iHeartRadio. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows. In 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys.

Then, everything changed. There's been a bombing at the TWA terminal. Just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged. Terrorism. Listen to the new season of Law and Order Criminal Justice System. On the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. I was diagnosed with cancer on Friday

and cancer free the next Friday. No chemo, no radiation, none of that. On a recent episode of Culture Raises Us podcast, I sat down with Warren Campbell, Grammy-winning producer, pastor, and music executive to talk about the beats, the business, and the legacy behind some of the biggest names in gospel, R&B, and hip-hop.

Professionally, I started at Deathwell Records. From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that drives it. Listen to Culture Raises us on the IHeart Radio app Apple Podcasts or wherever you get your podcasts. Why are TSA rules so confusing? You got a hood of you. I'll take it off. I'm Manny. I'm Noah.

This is Devin. And we're best friends and journalists with a new podcast called No Such Thing, where we get to the bottom of questions like that. Why are you screaming at me? I can't expect what to do. Now, if the rule was the same, go off on me. I deserve it. You know, lock him up. Listen to No Such Thing on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. No such thing.

This is an IHeart podcast.