StarTalk Radio - Things You Thought You Knew – Kicked into Orbit

Episode Date: June 23, 2023

How do bikes and motorcycles stay up? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly explain how to kick a ball into orbit, what’s going on with cricket, and the physics of bicycles. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.Thanks to our Patrons Shonuff Brown, Sam, Gary Gaskin, Rodney, james allen, and Daylon Burt for supporting us this week.Photo Credit: NASA/W. Liller, Public domain, via Wikimedia Commons Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Okay, so the high wire, the reason why they carry this big stick that's left and right, okay, it's not to balance them. No? That's not what it's doing. Really? No. Okay. No.

Now you've got me. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. Gary, what do you got lined up today? Right. So we've had some questions, and one of them landed right in my backyard. It's how hard would you have to kick a soccer ball, or if you want a football, to get it into orbit?

Now. Right? Okay. People are dreaming. People are dreaming superpowers on this one. Aren't they just? want football to get it into orbit. Now, right? Okay. People are dreaming. People are dreaming superpowers on this one. Aren't they just? So now, just so as you understand, here on planet Earth, the highest recorded kick in the professional game, and this might surprise people, 131 miles per hour.

So... Okay, I didn't see that coming. I didn't see that coming. I didn't see that. Neither did the goalkeeper. That's pretty high. Gone in an instant. And who did it kill? Nobody. This record is...

It was like a bowling ball, knocked everybody down. Yeah, no surprise. This is a Brazilian guy called Ronnie Heberson. And he's done it a couple of times. He wasn't a one and done on this sort of speed. So he's got previous for it.

So it's interesting that the design of the new balls has enabled them to travel faster, which is speeding the game up, which is exactly what everyone was after. What I wonder is, because I don't study soccer balls, I know it's a big deal, you know, before every World Cup, but the

amount that the ball compresses so that when it's coming off your foot, there's not only the speed of your foot that's translated to the ball, there's the recoil of the ball off your toe for you having compressed it. Yeah, there's the recoil of the ball off your toe for you having compressed it. Yeah, there's the

deformation and then the... But it's not just a deformation because you can deform something that doesn't bounce back and then it's no good, right? It's got to have that sort of... That's the Tempur-Pedic ball. Yes. Memory ball.

That would be a really slow game. Slow. Memory balls. That'd be a slow, really slow game. Slow, slow game. Very comfortable. Very comfortable, slow game. It wraps your toes and your toes don't want to leave.

Yeah, exactly. But no, it's interesting because you're now starting to roll this out. Is it an American football you want to kick

into orbit? Do you want to go away from inflated balls and then get, you know, what's it going to take to get a baseball into space, a golf ball into space? You know, where does your mind take you as to the sort of projectile aspect of it? But I was surprised because I didn't think the top speed of a soccer ball would be anywhere near 130 miles an hour. Yeah, neither did I. Plus, when I played Little League,

and I have to think about why this is true, but I could always hit a Spalding pink ball way farther than a baseball. Oh, yeah. And that's obviously an air-filled ball that responds quickly. But I also unraveled a baseball. Have you ever done that? Maybe not you, Gary.

No, not lately. No, American. Chuck, Have you ever done that? Maybe not you, Gary. No, not lately. No, American. Chuck, have you ever done that? Yeah, by mistake. I hit one so hard. You know, I think they call it tearing the cover off the back. I think that's what they refer to it as.

Then you woke up, and then what happened? This sounds an awful lot like a Robert Redford movie. Yeah, I saw that movie. Right. Yeah, so you unstitch it and remove the leather and then there's basically

rubber bands that are just, it's a continuous sort of rubber, it's like rubber bands. And you keep doing that and then there's this like little string.

Yeah, it's basically stringy rubber. And then there's a like little... String. Yeah, it's basically stringy rubber and then there's a little pink ball. Last I did this, I don't know if it's different today, little pink ball and my pink ball had liquid in it and I thought,

what? What's up with that? It's like the size of a marble, a little bigger than a marble. A mini planet in the middle. A little magma right in the center.

It's the core. It's the center. It's the core. It's the core. It's the core of the baseball. Okay, so here's the thing. So you want to know a cool fact? Please. It's a cool, stupid, geeky fact. All right.

The escape velocity for any object. So for Earth, it's 7 miles per second. Okay. That's a lot. That's a lot more than 131 miles per second. By the way, yeah. So he ain't kicking it in an orbit. Here. Yeah, I was going to say, maybe Superman could kick a ball that hard.

Okay. So here's... Oh, by the way, so it's not a matter of strength, okay? It's a matter of speed of your foot. So Superman is strong, but is he fast? Now, he can catch a speeding bullet. He can catch a bullet, I guess. Exactly.

That's pretty fast. He's very fast. He's not Flash fast. No, no, he's not. Right, right. He's probably the second thing after Flash. And he has super everything that's human, which we once discussed, Chuck. We discussed his flatulence.

Yes. We concluded he must also have super flatulence. But you have to dig that one out of our archives. That's on YouTube. Yes. Super flatulence. By the way, he wouldn't be the only one. No.

Okay. So. Not that I'm bragging. Here's an interesting fact. So you take the escape velocity for a planet, okay? Yeah. And divide it by the square root of two. Mm-hmm.

And that's the speed you need to get into orbit. Okay. It's kind of a cool fact. So, okay. Okay. So what is seven divided by square root of two? I'll do that right now. Please do.

Seven divided by square root of two. You get five. So, the space station and the space shuttle and Elon Musk and all these folks orbit the Earth at five miles per second. Right. all these folks orbit the Earth at five miles per second. Right. So that's lower than the escape velocity, obviously, because you're still in orbit.

But escape velocity and orbital speed, low orbital speed, are precisely related by that formula. In fact, the derivation of that was on my general exam for graduate school. You can derive how and why that's true. Straightforward, but you have to know that that's a thing, all right? And then figure out how to do it. Anyhow. Anyhow.

The point is, 130 miles an hour, it ain't happening on Earth. So where was it going to happen? So I take my ball and I go off, off world. Okay. And where am I going to go to get myself my jollies about kicking the ball into deep space? Okay. So Mars is not going to work. Okay.

You're not fast enough for Mars. You're not even fast enough for Pluto. Crushing my dreams here, Neil. You're not fast enough even for the largest asteroid is Ceres. In fact, Ceres is so large. C-E-R-E-S from the root of cereal comes from that, by the way. Ceres was the goddess of harvest, I think. One of these farm goddesses.

And we get cereal from that root word. So, point is, Ceres is so large as an asteroid that its own gravity shaped it into a sphere. Oh. And after the Pluto debacle… Oh, we're not going there again, are we? No, we're not. But round things too small to be planets are called dwarf planets.

Pluto got demoted from planet to dwarf planet status. And Ceres, which was in the ranks of asteroids, got promoted from asteroid to dwarf planet. Right. Right. So on Pluto and Ceres, the escape velocity is about, what did we get?

About a third of a mile an hour. I can do that. No, no, no. Sorry, sorry. Mile per second. Excuse me. Third of a mile per second? Yeah, you ain't getting it.

No, that's not happening. No, that's nowhere. You're not having it. Wow. Right, right. So, these are big objects. These are, you know. Yeah.

They're hundreds of miles across, these objects. Yes. Okay. So, the question is, what size object can we satisfy Gary's Superman urges? hundreds of miles across these objects. Yes. Okay. So the question is, what size object can we satisfy Gary's Superman urges? So let's look at big comets. So Halley's Comet,

not as big as they come, but it's, you know, we've all heard of it and it's visible. Okay. That one, it's like half a mile an hour. Really?

Yeah. Oh, we could do that. No, but then how are you going to play the game at all? Oh, no. I'm going to take some charms. I'm going to get some charms. We're all going to go up. We're going to kick balls from one asteroid to another.

Oh. Oh. I see. Just don't chase after the ball. No, it'd be like golf. You're going to land it on another asteroid. Oh, oh. Right. I see. But you better just don't chase after the ball. No, it'd be like golf. You're going to land it on another asteroid as it's going along. Okay, so we can all run at least one mile per hour. So if you run too fast, you can jump yourself into orbit and to escape velocity.

So you're right, Gary. You'd have to get a configuration of asteroids and comets. And again, all these are ten, you know, two dozen miles across around there. Practically anything we throw as humans or kick

would achieve escape velocity. So we need to wait for one of those meteor showers. We're going to get any joy out of that? Are they pursed? We can kick between them? No, no of those meteor showers. We're going to get any joy out of that? Are they pursed? Why? Because they're pursed, so we can kick between them. No, no, the meteor showers are tiny. Are they?

They're like the size of peas. Let's not do that. No, no, those aren't as... No, no, no. Excuse me. Excuse me. The comets we're talking about are 10, 20 miles across. The asteroid that took out the dinosaurs was six miles across.

Ow. Right. Yeah. Okay, you don't want these... This is not what's falling in a meteor shower. If comets and asteroids these large… Not even Bruce Willis could help us. Exactly.

If they were what were falling in a meteor shower, that's the end of all life on Earth. Yeah. Let's not do that. Yeah, let's not do that. Right. So, yeah. But it made for one hell of a soccer game.

Wouldn't it, Joss? So going from a few dozen miles up to like a few hundred miles is a very big difference in escape velocity for us. And you're right, Superman could do it at all times. Oh, and by the way, that old adage, what goes up must come down, you know, that grandma said or everybody else. That's only true if what you throw up

does not achieve escape velocity. If it goes higher than seven miles per second on Earth, it will never come back to Earth. Wow. It'll stay in the solar system, but it'll never come back to Earth. Now, if you wanted to leave the solar system, what you do is you say,

what's Earth's speed at our orbital speed at our distance from the sun? Right. Okay. If I take that speed, which is 30 kilometers a second, okay, about 18 miles per second, multiplied by the square root of two, I'll get the escape velocity from the sun at Earth's location. Ah. So, it works beautifully this way. So, if you want to

throw something that not only never comes back to Earth, but also never leaves the solar system. Leaves the solar system. You take the 30 kilometers a second multiplied

by square root of 2, which is 1.4. So, that's it's like 400, it's like 4, what is it? 30, 1.4,

45 kilometers per second. That comes out to be about 30 miles per second. If you get 30 miles per second like straight out, it's gone. You're gone. You're gone.

So we're going to need that equation. That's mathematics. When we decide that we're going to bug out of this particular solar system. Oh, you have plans. Yeah. Of course we have plans. So that's the only way I can help you here, Gary.

No, that's cool. Because we are not physically able to achieve this. Correct. Thank God. Thank God. Thank God. Because it'd be the worst damn soccer game you've ever seen. Can you imagine? If someone gets angry and they kick it into orbit.

Kick the ball and it's just, there you go. Can you imagine? It's gone. You go home and your father's sitting there saying, well, where's your ball? Well, John kicked it into space. The bully, the soccer bully. You go and get that ball right now.

I haven't spent my time. It would just be chaos. Oh, here's an interesting fact. If you... Okay, if you don't achieve escape velocity, the ball will want to return to the spot where you kicked it. In an orbit. Okay.

The problem is, Earth is in the way. Yes. So if you shrunk Earth down to a point, but you still floated up there and kicked the ball, and you didn't quite achieve escape velocity, it will make this huge elongated orbit come around

and then hit you upside to back it ahead. But right now, Earth is in the way. So it'll hit Earth on the other side of the Earth. So the interesting thing about orbits, the point you launch it is a permanent spot

of the orbital path of the object itself. Basically a boomerang. Suckerang. Yeah, suckerang. Suckerang. Yeah, and an hour and a half later, it'll hit you right upside the back of the head. Now that right there is a great prank.

Yeah. Where you kick the ball, and then you just go, stand right there. Don't move. Just wait. Just wait for it. Wait for it, bro. You're back. I'm going to need some patience, but it would be a giggle.

All right. So, Gary, that's all I can do for you here. That's more than enough, Neil. Thank you. Okay. You got it. Okay. So, what do you got?

All right. This, I suppose, really it's just human nature. Who's the better pop band, the Beatles or the Rolling Stones? Everyone has this kind of question and they want to sort of get them on together. Now, here we go, in a sporting reference. Is cricket, the sport of cricket, harder or easier than baseball? It doesn't make a difference. They both suck.

There's your answer. Chuck, for his nuanced point of view on the world. There you go. You know, I'm trying to be as subtle as possible. And you achieved it. You achieved your aim. Chuck, you got to admit that without Gary on the show, cricket would never come out of our mouths at all.

This is not true. You know, he rounds us. He completes us. This is true. All right. So let's back up. Let's back up here. All right.

Let me tell you, Gary, let me tell you the little bit of cricket that I know. Okay. All right. So I played Little League Baseball. Yes. I was catcher on the team. Our teams were the name after real teams. So I was on the Red Sox. And i was catcher on the team our teams were the name after real

teams so i was on the red socks and i was catching that go down with a boy from the bronx it was not a problem yeah the red socks hate the yankees but the yankees really don't care right yes and that's how you know the yankees are better exactly that's how you know the yankees are better than the red socks because you go you go up to a certain part of the Northeast and I don't care what happens. It's Yankees suck. I know. Yankees suck.

But you walk around New York and you never hear one word about the Red Sox ever. Do you remember when the Patriots won the Super Bowl and there's a Patriots parade? Yep. This is in February. That's right. This is in Boston,

and the crowd spontaneously started saying, Yankees suck. Yankees suck. At a completely different sport. At a completely different season. And they're celebrating the world champion win. But they couldn't resist saying Yankees suck. Right.

So I had no problems wearing a Red Sox uniform. I was also an all-star. Of course. Of course. I was all these things. Yes. Okay. I just happened to be all these things.

So I visit England for the first time, and I see them playing cricket. And I'm observing. Yeah. And I'm thinking, wait, the ball... Goddamn, boy, y'all played baseball wrong. The hell you doing out there? Now, why are there still damn sticks

in the middle of the field? Now, you know, somebody gonna fall. You got yourself a liability right there, son. That's what we're looking at. That's a wicket. That chuck, those three stumps in the ground with the little bits of wood on the top are the wickets. You have one at each end. They are 22 yards apart.

In America, we call that a lawsuit. That's what we call a lawsuit. Put that on the playground. Tell you right now, you're going to have four or five parents suing your ass in a minute. Okay. Okay. Anyway. I still don't get it.

Are the wickets, are the wickets like bases? Well, let me get there. Hold on. Yeah, yeah, yeah. It is, it is. So I'm there. And what am I?

I'm 14 or something, something. I also played stickball in the Bronx. All right. All right. So that's a game. That also played stickball in the Bronx. All right. All right. That's a game. That's a game. Now you're talking.

Okay. Got out the broomstick, and the rich kid had an actual stickball stick that he bought. And it looked a lot like my broomstick, but, you know, it just didn't have the threading at the bottom of the thing. You know what we did with that? We took it, and we beat that rich kid with it. Because how dare you actually bring anything other than a mop or a broomstick to this game? Chuck, I thought your anger management sessions were going well.

What has happened? We are the anger management sessions. Oh, we are. So I'm looking at it and I said, can I try? All right. And so, the bat is like twice the size of a baseball bat. And it's flat. On one side.

The face is flat, but it's got depth behind it. Okay, but I'm saying I'm hitting a ball bigger than a baseball. Yes. With a bat bigger than a baseball bat. It's at least twice the size. And it's flat. And I said. You know what we call that?

We call that cheating. Okay. So I get up there and they pitch the ball. Is that the right word? I don't know. Bowl. It's a bowl. Yeah.

And it comes off. They go into the ground and come off. And I swap the hell out of the ball. And the ball goes way... And I don't know the point of the game, but I knew if I had to hit it far, I hit that sucker far. And what I didn't do right was

I ran down to wherever I was supposed to run, but I dropped the bat. Ah. See? Wait, wait a minute. You've got to carry your bat, Chuck. You were not allowed to drop the bat in cricket? No, no, no.

You have to carry your bat, run to the other wicket, which, as I said, is 22 yards away. And if you've hit it far... I mean, you have to treat a cricket ball a bit like a baseball, as if you've got an allergy to leather. As soon as it comes near you, you smash it as far away as possible. Now, if you hit it over the boundary, you get six runs.

If you hit it and it bounces before the boundary and goes out, that's four runs. Now, that stops you having to run four times between the wickets. So it's just an easy way to get your runs. Wait, so I can stay at bat, correct? Yeah, if you hit it over the boundary. Which I did. I hit it over the outer thing,

but I just stayed there and I hit it again. And I had another time, I think this bounce, but then they caught it after the bounce. But then I run, right? That's when I ran. I'm trying to remember the details of this. If it bounces and someone catches it, you still have to then get your runs in.

Correct, correct. There's no way this game could be played in Philly. Because nobody is going to allow you to hold on to the bat while you run to any place. That is a recipe for disaster. Cops will pick you up, depending on your skin color. If you run in with a bat, as fast as you can, with a bat, in the streets of America. You're dressed all in white, right? Because cricket, the traditional uniform of a cricket player is all white.

So no forward face stealing, a base, right? No sliding. Oh, you do slide. You'll sully your clothes. The thing is, the elite bowlers, and there's all different types of, just like in baseball, you'll have someone who's a specialist as a slider, curveball, someone's got three-digit speed. And cricket has the same, although what they're doing

is they're bowling into the ground. And a certain length of bowl allows the batsman to work or not work. So the top speed will be just over 100 miles per hour. So they're spinning the ball. So it hits the ground, then the friction between the spinning and the ground will have it veer. Exactly, but then the condition of the ground is a big difference because if it's grassy, you've got moisture in the grass,

and therefore it's going to have less abrasion, less friction. Yeah, it's going to eat some of the momentum of the ball. And then the slower bowlers will hold the ball in a certain way. They'll walk, because the seam on a cricket ball is a, if you imagine two semicircles brought together,

is a raised seam. So it's the equator. Thank you. It's an equator. It's an equator, but it's raised. So you work across the seam, the seam changes angle, and the bowler will, if they're really talented spin bowlers, they will bowl it out the back of their hand, not forward down the

seam. So there really is a talent. And the slower spin bowlers, it will come to you coming from right to left. And then when it hits the ground, it will almost do a 45-degree cut across you and confuse the hell out of you. If they spin it really, really fast. And there are some real spin demons out there.

They're so talented. Okay, let me just say, none of them confused me. Whatever they were doing, I was... Neil, you're an all-star. Maybe they're not skilled bowlers. They were not skilled bowlers, maybe, but... I am confused as to how anybody can watch this. Because what the hell are we talking about?

I've got something that's going to fascinate you. If you have an international game, say, for instance, India played England at cricket. Okay. That would be an international game. I know it's the number one sport in India. It is absolutely

off the chart when you see how they absorbed the game. Plus, if I were from India, remembering the history with England, I'd want to beat your ass every single time. And by the way, by the way, speaking of the history of England and India, there's no way I would play a game where an Indian guy could run at me with a bat.

I'm sorry. If you're British. No, it's not the bat. It's not the bat. It's all of a sudden someone who has the ability to bowl at you at 100 miles an hour. And if they bowl at a certain length and they bowl short, that ball hits the ground, obviously, but comes up round about head high. It could hit you. Yeah. Okay. Oh, so you're allowed to hit somebody.

Yeah. Well, they're not going to wear a helmet, but you get body line techniques. So they'll aim and it'll pitch up around here and you find batsmen will duck and all the rest of it. So the amazing thing is what goes on in the science of how they will shine one side of the ball, leaving the other side of the ball in a matte. So that then enhances Magnus effect. Well, that makes sense. There's all sorts of things going on within the game.

I would say the Magnus effect in that case, because the ball is not even symmetric in what is smooth and what is not, then it could end up corkscrewing, perhaps, depending on which way it's spinning. So it's not always curving in one direction, but it could actually take on another kind of path that you can't foresee

unless you have really good vision watching the thing spin. So, let me ask you, with the bat, I use the flat side, but can you use the other side, which is angled? They do. So, when you get a really, really clever spin bowler, that ball's

coming in maybe 40 miles an hour, maybe even slightly slower. And what they do is they reverse sweep. So they go from, say, from their right-hand side, and as they know that ball is going to cut across them going left, they will reverse sweep that out away. So they'll use the backside of the bat. I've seen that.

Yeah. Okay. So, Chuck, as I was saying, with an international game, say India versus England, it's a test match. That's what they're called. And this will turn you off cricket for life. It can take four days to complete. A game?

Yes. Yeah. Okay. Because it was slower than baseball. Yeah. So the thing, this is so, it's where kind of baseball gets all the statistical, patient, deep thinking.

This is where cricket has such an audience for some people around the world that absolutely adore it. Plus the fact they get to bowl balls at England at 100 miles an hour. Perfect. Yeah, yeah. Yeah. So the audacity of England to play any sport against a former colony. I just want to put that out there.

I know. There's a lot of scratching of head and thinking, oh, gosh. I'm just putting it out there. You know what? See, the thing is, when you face a pace bowler, someone who has got triple-digit speed, it's not just your ability to be a good batsman. It's a test of your courage.

This thing is coming at you at a rate of knots that is frightening. All right, so thank you, Gary. I didn't know about all the spinning of the ball. Oh, no, it's a really fascinating sport. And I didn't pay close enough attention to know that half was shiny, the other half wasn't.

So I was good at hitting it. After that, they could probably figure me out and just pitch around me or something. You know, there's some finessing with carrying the bat and getting used to that. But when you get a good bowler, they'll work out because they won't just do one type of bowl at you. They'll come at you with a

whole variety just to keep you going. And they'll find out what your kryptonite is and then they'll hit the stumps. Okay. Hey, listen, I don't want to offend anybody who loves cricket, but any sport that makes baseball look exciting might want to be reconsidered, is all I'm saying.

But you don't want to offend anybody, right? No, I don't. Anytime someone says, I don't want to offend anybody, they're going to offend somebody. Okay, so the test matches can take four days long. I don't mean to sound racist, but... I don't mean to sound sexist. There are different formats

of cricket, like T20 or the IPL, the Indian Premier League, which are short format, 20 overs each, and each over is six bowls. And they're done in a couple of hours.

And it is along the lines of baseball. There's loads of razzmatazz. There's loads of coloured uniforms. And, there's loads of colored uniforms, and the game is all about hitting that ball as far away as possible. Gary, you mentioned something about motorcycles the other day. What was your issue there? Why motorcycles can stand up?

They're transformers. That's why. Next question. Okay, we're done here. So when you say stand up, not after you put up the kickstand. You mean it can just roll on its own without anybody on it. Or a person can stand on the seat while the thing is rolling.

For example, I've seen that. Yeah, the display bike teams, they're fantastic. Yeah. So for the longest while, and I count myself among those who would give the answer that you have spinning wheels that are basically gyroscopes and that they gyroscopically stabilize the motorcycle. By the way, the same would apply to bicycles, of course.

Yes, right. Because, in fact, there was a famous scene and famous because people talked about it. because people talked about it. I thought it was clear and present, but I didn't realize how many people didn't know that if you set a bicycle moving down a hill with nobody on it, it'll just keep rolling. It'll keep going until it hits something.

Until it hits something. For a long time. Longer than you would expect. And that was revealed in the movie Butch Cassidy and the Sundance Kid. Yes. In one of the romantic scenes with Robert Redford

and Catherine Ross, I think it was. It was also revealed in my driveway as a kid, and I got into a hell of a lot of trouble because, boy, do you know how much that bike cost? I cannot believe that you were throwing that bike down. What? That's what you see. You run, and you just let the bike go.

Yeah. Then it becomes a ghost bike. Yeah, yeah, yeah. Yeah. So that was a common explanation. And I've even given that explanation. But I recently read that someone did an experiment where they added wheels that spin the opposite way of the wheels.

They're not connected to the ground or anything, but they spin in the opposite direction, which cancels out the physical angular momentum of the rotating wheel. So that the whole system no longer has a net gyroscopic force operating on it. Interesting. And it still stayed up as it went down. So it's like,

it's rolling down the hill, but then let's say you have like a balancing pole with two wheels on it, and then they're spinning in the opposite direction. Correct. And they figured out a way

to do this so that then there's no net gyroscopic stabilizing force because it's been canceled out just through the laws of physics. So it's still maintained its course. And so here's what's going on. And it's fascinating. It's more complicated with a bicycle than in other examples I could give.

But a system is stable in whatever it's doing if its center of mass is as low as it could be, okay? Within a range of… Which is the whole deal with motorsport, where they're always trying to get the center of mass as low as possible. Yes, and electric cars put their batteries not on the roof, but as low as possible. On the bottom. So that you have the low, because watch what happened.

If the center of mass is so low that anything you do to that object raises the center of mass, it doesn't want to do it. It always wants to bring the center of mass as close to the center of mass, it doesn't want to do it. It always wants to bring the center of mass as close to the center of the earth as possible. That's why, you guys remember Weebles? Chuck, you remember Weebles?

Weebles wobble, but they don't fall down. All together now. Okay. So there they go. So you push them, and then it writes itself back up. Well, what's happening?

Because in its righted position, the center of mass is as low as it possibly can be. And if you do anything else with a Weeble, you are raising the center of mass. And that's not what the Weeble wants to do relative to Earth. So once you've raised the center of mass, it says, I'm going back to where I was. And the center of mass drops down. It gets closer to the center of the earth. In that case, only by a few inches, but it'll do it. It's the same reason why boxes of cereal boxes need that caution.

It says, when you open it, notice there might be some settling of contents. We call it settling of contents, but what's actually happening is every cereal flake wants to get as close to the center of the earth as it can. That's this job in life. And so that's why if you jiggle it, it doesn't puff up. If you jiggle it, everybody's jockeying to get as low as it can inside the box. To get as close to the center of mass as possible. So it turns out the design of a bicycle where the center of mass of the front section and the back and the chair is that if you set the thing rolling down the hill and it begins to lean, what will happen is the front wheel will turn into that lean.

Correct itself. Okay? And right itself. Okay, so the bike won't necessarily go in a straight line, but if it curves, its tendency will be to right itself. So, Neil,

I'm on a higher wire on my bike because I'm a bit like that, and I've got this enormous big pole. Okay, wait a minute. Now you want to ride a bicycle. Why, why, why? You want to ride a bicycle on a high wire?

Let's just do the high wire first, and then we can stick you on a bike if you want. Please. Okay, so the high wire, the reason why they carry this big stick that's left and right, okay, it's not to balance them. No? That's not what it's doing. Really?

No. Okay. No. Now you've got me. It's not, okay. That balance pole is floppy. Have you noticed that? It's not a rigid pole. Chuck, I so thought you were going to drop a gag there.

Yeah. I was going to say it happens to a lot of high wire washers, but it's okay. But I'm not going to do that. Of course not, no. I'm going to leave it alone. Okay, so it's not a rigid pole because you could say you can use that to balance. No, because they're not using it to balance. They get a floppy pole

so that the side on the left flops downward and the side on the right flops downward. Okay? And the system, the high wire walker plus the pole, has a center of mass now that is so low that if he starts tipping to the left, the center of mass is raised because the pole is out there counterbalancing him. Okay?

So, yes, I'll use the word balance in that context, but it's all about the center of mass. If he tips, the center of mass raises, and it wants to lower the center of mass once again. So he can easily, I mean, if you still have the talent to do this, stay on the pole, on the wire, because the pole plus the wire, him on the wire, is the lowest center of mass of the system that you can get. And you don't see him walking with this up over his head, do you? You don't see that. Okay?

He's holding it down low. It's always held pretty low right down by the waist. Right by the waistline. Correct. So that's the whole thing. The whole thing is that we're talking center of mass always to keep this thing upright, to keep it in a good place. So, Gary, now you want to have the high wire act on a motorcycle.

Okay. Not a bike. Let's not go too bad. Okay. Not a bike. Let's not go too bad. Okay. So there's probably some kind of groove in the tire for it to stay on the wire. Well, you may take the tire off and use the rim. Oh, that would work.

Oh, for sure. Because the rim is concave, right? So that's an interesting way to make that work. But if you are up above the wire relative to the tires, you'd want the floppy stick, what do they call it? You'd want that to go even wider out to the sides and be even more droopy. And that would give you tremendous stability

in doing this exercise. So, Gary, I don't know. Did I go where I had to go in that answer for you? I think you did, yeah. I mean, just thinking about would it work then for electric motorbikes? Because there's no engine, and generally the engine is the lower part of the whole thing. Oh, oh.

How would that then work in the same way? Because I've seen motorbikes where the batteries go up one of the two. Yeah, I was going to say, the difference is that the weight of an engine on a bike is pretty evenly distributed so that it makes the bike balanced to ride. So once you just have batteries… It's between the rear wheel and where your feet go. It's not up in the front wheel. Right. It's between the rear wheel and where your feet go. It's not in the front wheel. Right. Right.

So that's normally the way they position engines. But for a battery, you can see it like they sit right under the front fork sometimes. And then sometimes at the bottom of the bike. So it's interesting. I don't. So I'd have to conclude, Gary, that if they're putting batteries up the down tube and up the tubes, then that's changing where the center of mass of the system is. And it can only be less stable for that reason.

Yes. Yeah. Perfectly. What we need is delivery riders on less stable bikes doing 30-odd miles an hour down the street the wrong way with our food. Perfect. Because in the city, Uber Eats are people on motorized bicycles. It's not people in cars and all the other delivery systems. So that's all I can tell you on that, Gary.

Were you good to go on that? Yeah, so just remember Weebles. I'm fascinated by the balancing pole because that is something I'm thinking, well, that's for balance. But it's not. It's a different thing altogether. It's a different, I mean, there's some, yes.

For what you said, the center of mass. It's for center of mass. It's to keep the center of mass as low as possible. And in some cases, the center of mass is, in fact, I think it's in every case, the center of mass is below the wire, I think it's in every case, the center of mass is below the wire. Oh. So that as you tip, the center of mass says,

I want to get as low, again, I want to get as close to the center of Earth as possible. And that's directly below the wire. And you're on top of the wire, so everybody's stable. There it is. Interesting. So it's not as dangerous and you can make out then i think most things are not that's correct if you boost the odds in your favor by training by

practice by physics then anyone else looking at what you do is imagining themselves in that situation and how dangerous it would be for them. They're not imagining you in that situation, imagining how non-dangerous it otherwise is for those who are trained. All right, that's all we got time for. This has been another installment of Things You Thought You Knew.

This time, a StarTalk Sports Edition. Neil deGrasse Tyson here, your personal astrophysicist. And I've been with Gary O'Reilly and Chuck Nice. As always, I bid you keep looking up.