StarTalk Radio

Things You Thought You Knew – The Color of the Sun

48 min
Dec 30, 20255 months ago
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Summary

Neil deGrasse Tyson and Chuck Nice explore three misconceptions: the sun's actual color is white (not yellow), the acoustic properties of lightning and weather phenomena, and why friction is essential rather than problematic for physics and everyday life.

Insights
  • The sun appears yellow only at sunrise/sunset due to atmospheric scattering of blue wavelengths; direct overhead sunlight is white, demonstrable by snow appearing white under daylight
  • Lightning thunder's distinctive crackling sound results from multiple shock waves generated by kinked lightning paths with constructive and destructive interference patterns
  • Friction is fundamental to all motion and transportation; without it, walking, driving, and steering would be impossible, and astronaut reentry depends on friction-generated heat dissipation
  • Atmospheric conditions directly affect acoustic properties: snow absorbs sound (making cities quieter after snowfall), and snow crunches only at temperatures below 20°F when frozen solid
  • High-frequency sound dissipates over distance, converting to lower frequencies, which is why distant lightning sounds like rumbling while nearby lightning sounds like sky-tearing cracks
Trends
Science communication through accessible explanations of counterintuitive physics conceptsDebunking childhood misconceptions using observable phenomena and experimental methodologyInterdisciplinary connections between physics, photography, art, and human perceptionAtmospheric science applications to everyday weather observation and predictionHistorical evolution of scientific method from Aristotle through Galileo to Newton
Topics
Solar Physics and Light WavelengthsAtmospheric Scattering and Rayleigh ScatteringAcoustic Physics and Sound PropagationLightning Formation and Thunder GenerationFriction and Mechanical PhysicsAstronaut Reentry and AerobrakingSnow Acoustics and Temperature EffectsColor Perception and Human VisionIncandescent Lighting and Color TemperatureShock Waves and Interference PatternsKinetic Energy and Heat DissipationNewton's Laws of MotionExperimental vs Theoretical PhysicsAurora Borealis Acoustic PhenomenaHail Formation and Atmospheric Instability
Companies
JP Morgan Payments
Sponsor providing automated payment solutions and financial technology services across multiple countries
Midnight Casino
Online gambling platform offering slots, roulette, and blackjack games with promotional offers
People
Neil deGrasse Tyson
Host of StarTalk Radio, astrophysicist explaining scientific concepts and misconceptions throughout episode
Chuck Nice
Co-host engaging in dialogue with Tyson, asking questions and providing comedic commentary on topics
Isaac Newton
Historical physicist referenced for demonstrating that white light comprises all colors of the spectrum
Galileo
Historical physicist credited with experimental methodology bridging Aristotle and Newton's understanding of friction
Aristotle
Ancient philosopher whose incorrect physics about motion and friction were later corrected by experimental science
Francis Bacon
Philosopher who advocated for experimental philosophy and conducted numerous documented experiments
Quotes
"The sun is white. Now, now, what's the man? Why you got to do that?"
Chuck NiceEarly in sun color discussion
"It's the atmosphere made of yellow. Okay? It's lying to you."
Neil deGrasse TysonExplaining sunset color misconception
"Without friction, life as we know it would not be possible."
Neil deGrasse TysonFriction segment introduction
"Friction is your friend. It is nice."
Neil deGrasse TysonFriction conclusion
"If everyone lined up and started running due-east, you will speed up the rotation of the earth."
Neil deGrasse TysonFriction and momentum discussion
Full Transcript
Join Midnight Casino and discover a whole new... WOOOOOOOW! With hot slots, jackpots, live casino roulette and blackjack at the ready. Come and play your way, get 103 spins when you spend 20 pounds on eligible games. Search Midnight Casino or download the Midnight app today. Midnight Casino Dunber, you decide. New customers only, restrictions and TNCs apply. 18 plus, BeGumbleware.org Hey everybody in the Start Talk of Versus. We've got yet another things you thought you knew episode. This time Chuck and I get into the color of the sun, whether acoustics and friction. Check it out. Welcome to Start Talk. Your place in the universe where science and pop culture collide. Start Talk. Begin right now. Welcome to the explainer zone. Yes! The explainer zone. Yeah, yeah, not the twilight zone. That's twilight zone. We're confused at the end. Explainer zone. Well you come out knowing more than you get when you will end some stuff. Right, and so I think there's no end to this just so you know. I will be calling you forever. So I want to talk about the sun, the color of the sun. Okay. All right. Well, and you know me, I don't see color. You don't see color. Sorry, we're already done here. So, so, so here's the thing. If you're a school child and you to draw a scene and you want to put the sun in the sky, what crayon do you reach for? Well, I was a very depressed child, so black. Okay, no, you knew about black holes, but yes, exactly. No, it's always a big yellow. It's yellow. It's always yellow. And this is this notion has been with us since childhood that the sun is yellow. Yes. And that's not true. It's not even close to being true. And so, yeah, I'm sorry. You know, I don't want to, well, you say, are there any kids watching? Please. You might want to leave the room right now because we're not sure if there's a crayola available for you to draw your little scenes with the house and the grass and the look. Okay. So here's the thing. The sun and broad daylight is too bright to look at. All right, without risking damaging your eyes. So no, unless of course, you have perfect eyes. So, so you don't do it. All right. So when is the time most people ever find themselves looking directly at the sun? When is that? Well, the only time I've ever done it is sunset and sunrise. The sun is sunrise. Exactly. Exactly. So not only do we have the yellow crayon in our crayon box from childhood, any time we actually ever find ourselves looking at the sun, either on purpose or by accident, it's low on the horizon. The sun is rising or setting. Right. It has a deep yellow color. Sometimes it's so deep it can be red, the amber into red. Yeah. So, and we know the sun isn't red. Of course, it's not red. We know that's a that's a. This isn't a Krypton. It's not Krypton. Exactly. It's a red. I had a red sun. So you know intuitively it's not red, but somehow you don't know intuitively that it's also not yellow. Okay. What color is the sun? It is white. Now, now, what's the man? Why you got to do that? What? See? What? What? Just like everything else. All of a sudden. Chup, not everything. We got a white commentary. You know what? Seriously, we got a... Must we whitewash all of history, including the sun? Really? So, yeah. So it's not yellow. Okay. It's not yellow. Now, I can give you evidence of this. If you need evidence, but I'm simply saying that as the sun gets... Let's look at Earth and there's the atmosphere wrapped around the Earth. If the sun is directly overhead or anywhere near directly overhead, it goes to sort of... Let's call that one thickness of atmosphere. Okay. Top to bottom. As the sun gets lower and lower in the sky, the path of light through the atmosphere is longer. Okay? Because now you got... There's that angle through it. And it's the lower the sun gets on the sky, the more and more atmosphere it has to pass through. And in fact, you can calculate how many equivalent atmospheres it went through. Okay? And you just need a little bit of trigonometry. It's a simple calculation. And if it's low on the horizon, it has goes through five, six, ten equivalent atmospheres. Gotcha. When it's low on the horizon. So whatever the atmosphere is doing to the sun when it's high up overhead, it's doing it ten times that. And more when it goes lower on the horizon. Okay. So let's see what the atmosphere is doing when the sun is overhead. Incomes white light. Okay. And white light is composed of colors as Isaac Newton demonstrated. All the colors of the rainbow, red, orange, yellow, green, blue, indigo if you must. Violet. Violet. Violet. Okay. So in it comes particles in our atmosphere that happen to be the same size as the wave length of light of the blue side of the spectrum, the blue indigo purple, a violet side of the spectrum. Those particles preferentially scatter the blue out of the sunlight. Preferentially scatters it. So it subtracts away a little bit, just a little bit. All right? The rest of the light makes it all the way to Earth's surface. But some of the blue gets scattered and that's why we have a blue sky. Nice. The blue sky is stolen sunlight that would have otherwise passed straight through. Look at that. Oh, great. Because this guy is really clear, right? Okay. So now watch. How beautiful is that though? Now let's have the sun get a little lower in the sky. Well, there'll be more of this going on. Okay. More of the sky. That's why on cloudless days into sunset, the sun gets deeper and deeper and deeper blue. The blueest sky, that's why sky blue is light blue. Right. All right? You want to talk about serious right home to mama blue is the blue sky that surrounds the twilight curtain of a sunset. Now you're talking blue, right? Okay. So so much blue is taken out that we now, Roy G. Biv, Red Orange, Yellow, Green, Blue, when it took out blue indigo violet, what's left? Red, orange, Yellow, Green. Okay. If you had those colors together, you're going to get an amber sun. And depending on how many particles there are, you'll get a red sun or you'll get a simple yellow sun on the horizon. And so you now look and so we have a yellow star. Look, it's yellow. No, it's the atmosphere made of yellow. Okay. It's lying to you. And if you say here's what you do, it broad daylight, if there's thin, serious clouds, okay, so it's safer to look up to the sun, look up the sun in middle of the day. Is it yellow? No, no. It is white. This is very disturbing. This is very, very disturbing. Because the clouds themselves don't change the color of the sun, it just dims it. So you look at a slightly dimmer sun behind the thin clouds as they pass. It's not yellow. Right. It's not yellow. Not only that, consider the following. All right. Now this takes a little extra thinking. Put your thinking cap on. Okay. And we, in another explainer, we address this, but now there's a different reason for it. If I have a sheet of paper and it's white, that means light reflected of it from it is an even mixture, an equal mixture of red, orange, yellow, green, blue, violet. All those colors together in optics makes white. Don't tell this to an artist. Right. It doesn't work on the easel. No, it's, they, they, they, it's just the opposite. And all right. It's the opposite. Yes, the opposite. You don't get black, but you'll get like sludge. You'll get sludge, right. All right. So the fact that the page is white means all of those colors of light are hitting that page. Correct. So that when they reflect off, you see white. Okay. So a white light illuminating a white piece of paper shows up to you as a white piece of paper. There you go. Okay. Now, white reflects all colors. Let me put a red gel in front of the light. Now look at the paper. What color is it? It's red. It's red. We kind of pinkish, but yeah. Yeah, that's right. So it reflects all colors. When now it's only getting red, it's going to reflect the red. It reflects all colors. The page is red. Right. You're right. Let's put a blue gel. What happens to the page? The page is blue. Same thing. Yeah. Okay. So if the sun were yellow, then snow would be yellow. It would be yellow. What's by the way, sometimes snow is yellow and it's not from the sun. And whatever you do, whatever you do, stay away. Don't keep the yellow snow. Stay away from that snow. The fact that snow looks white right is evidence that it's being illuminated by white light. Wow. That white light is either sunlight or a moon light. That's right, which is also reflection of sunlight. It's your reflected sunlight. There you go. This is so disturbing. So so so so. So I'm just trying to be honest. I'm just trying to put it out there. And just and by the way, let me take you want to go up a notch. No, you're ready to go up a notch on this. I don't know if I'm ready to go up a notch. I don't think you're ready. Okay. So um, white is the sun. Hate where this is going already. Relative to incandescent bulbs. Right. Okay. Your kids will have no memory of incandescent bulbs. But all timers, if you're over 25, you're an old timer. You remember bulbs that we get hot when you put them in. Okay. It was a bulb with a little piece of wiring. Okay. Why I used to light up. That sounds like a Ken Burns special. I'm a guy in the porch. Right. I remember the days when it had a bulb with a little piece of wiring. Now that wire would light up and get hot. I would probably put a switch. We put a switch in the game of life. Now first look like magic. Okay. We got put you on the list of the next Ken Burns special. The origin of the light bulbs. So all right. So we wasn't I forgot. We opened this thing. Incandescent bulbs. Okay. Incandescent bulbs. Incandescent bulbs when you turn them on. The temperature of the filament is not as high as the temperature of the surface of the sun. And so the higher the temperature, the more full that spectrum becomes. So if you look at the spectrum of a bulb in your house, or an incandescent bulb, it's very weak in the blue section. There's some blue there, which is why blue still looks blue under that light. But the blue is very weak under an incandescent light bulb. Okay. So if you bring out film that needs the full complement of blue, and you take a picture under incandescent lights, everything is going to be red. That film, if it needed, the blue is called daylight film. This is why there was a difference. Again, I'm only talking to old-timers here. There was indoor film and out tungsten film and outdoor film. And the outdoor film was color balance to get the entire spectrum of the sunlight. If you took indoor film and put it outside, that indoor film is too sensitive to blue because it's making up for the feeble blue coming out of a bulb. And it goes out and it's getting all the blue it ever wanted. If you have indoor film, it took a picture outside, everything looks blue. Because it was hypersensitive to blue. And the sun has plenty of it. But okay, so to a photographer, sunlight is blue. It's highly blue. And they have to correct for that if they're going from indoors to outdoors. They have to redo the color balance on a white sheet of paper to account for the difference between indoor lighting and outdoor lighting. Now, here's where they all got it wrong. But they're not going to change it because they're deep into it. You ready? Now, we have the blending of science and technology with art. You ready? Here it is. If an artist draws an arctic scene, what color is prevalent? White. And what color? Blue. Blue. Right. If an artist draws Dante's hell, what color is prevalent? Red and orange. Red and orange. Okay, so emotionally, we think of blue as cold. And red is hot. Photographers will tell you we need to reduce the temperature of the light, which means make it colder emotionally. But the only way to do that is to get more blue in it, which means upping the temperature of the tungsten that they have shining on you or to put more blue into it. And in the old days, that meant a hotter light bulb. So they said, we need a cooler scene. They had to have a hotter bulb. We need a warmer scene. They had to have a colder bulb to do that. Wow. And that language is still embedded in that entire profession. Yep. That is true. The opposites and they meet in the middle and they deal with it. Now, the opposite is art and technology and science and the physics of light. JP Morgan Payments JP Morgan Payments helps you drive efficiency with automated payments and intelligent algorithms across 200 countries and territories. That's automation driven finance. That's JP Morgan Payments. JP Morgan Internal Data 2024, copyright 2025, JP Morgan Chase & Company, all rights reserved. JP Morgan Chase Bank, and a member of FDIC. The positives held non-US branches are not FDIC insured, non-deposit products are not FDIC insured. This is not a legal commitment for credit or services. Availability varies. Eligibility determined by JP Morgan Chase. Visit jpmorgan.com slash payments disclosure for details. I am Olican Hemraj. And I support StarTalk on Patreon. This is StarTalk with Neil deGrasse Tyson. I got one for you. How about acoustic effects in climactic phenomenon? Really? Yeah, I just thought about that. Okay, it sounds like something that if somebody sets me at a cocktail party, I'd be like, I got to get a drink. I'll be right back. But they will come back because it's intriguing enough, but they got to get priced. They got to get prepped. They're chemically prepped for it. It's that. All right, so let's start out with thunder and lightning, for example. So lightning in its path between the ground and the clouds, or between a cloud and the cloud, never goes in a straight line, because it's finding the path of least resistance, the entire time unknown to you, this is what it's doing. And then when you see the lightning strike, it is already a predetermined path between one point and another. All right. Now, it turns out the sound of lightning is simply the shock wave of rapidly heated air by the bolt of electricity moving through the air, which is extremely hot. Right. Okay, it's thousands of degrees. But what matters is that it is the air is some other temperature, and then it is instantaneously made extremely hot. This creates an expanding shock wave that we hear as thunder. Okay. Now, because the path of the lightning is not straight, there kinks in the root. So each segment of that kinky lightning has its own generated shock wave. Okay. Right. So now you have multiple kinks generating their shock waves, and you can have constructive and destructive interference of competing shock waves. That makes so much sense. Which is, oh, go ahead. Okay. Okay. Oh, this is good. Okay. So our research has found the lightning 50,000 degrees Fahrenheit. Yes. Okay. That's hot. Okay. All right. I'll send it. So now watch. So with these different segments, that's why a single lightning bolt. And by the way, the lightning bolt is not all the same distance from you. Okay. The parts that are a little closer that are on the ground. If it's cloud-to-cloud, the part directly above you is closer than farther away. So the sound will hit you at different times. But it's the one generated event. Right. So that's why the lightning can go, and snap crackle, but it's, but it's, but it's, okay. That's why it's not just one acoustic experience. It is a, it is a highly, I love your thunder. I, okay. You like my thunder? We have to isolate. Oh no. What just happened? You, you, if I see that on a meme, I will call, kick you. My god, I am so, I'm going to kick that end. It's so going to be a meme. So, so here's the lightning, and it's because of the acoustical configuration of the lightning bolt itself. That is wonderful. I'm serious. That is so great because one of my favorite things in the world is to hear lightning. I'm to hear thunder, but not the rumbling thunder. The thunder that sounds as if it is tearing the sky. Yeah, because that, it's okay. I'm getting there. That's my next point. Okay. So, so that, so I'm just simply accounting for, by the way, constructive and destructive interference, if you're not familiar with that. So, so sound travels in waves, say, crests and troughs, and that's, this is a pressure wave through the air. It hits your ear drum, your ear drum vibrates, we interpret that as sound. So does your body, too. By the way, there's certain frequencies of sound that are longer, sorry, there's certain wavelengths of sound that are longer than what will fit in your ear drum. So your ear drum will have a hard time communicating it to your brain, but the length of the wavelength is about the size of your chest cavity. That's the low frequency long wavelength. And so there are some sounds that you feel more than you hear. Oh, it's the rhythm section of the beat. Well, what are they called the beat, the beat boppers? What are they called the beat bopters? Yes, yeah, yeah. But if I heard Lightning starting to do that, it was like, whoa, there is a God. God is a DJ. So here's what happens. The Lightning sound is a huge cacophony of frequencies of sound energy. Okay, high frequency, low frequency. But here's the problem. High frequency doesn't travel very far. It's easily disrupted. It can easily lose its energy, relative to the energy that it started with. And if high frequency sounds loses its energy, it becomes lower frequency sounds. So the farther away you are from a lightning strike, the lower is the total cacophony of frequencies that reach you. So lightning on the horizon is okay, if you have a pet dog, they hear that and they notice that. And they might start trembling and you don't even know why, because that frequency is below what you can hear, the dogs hear it. All right, as the storm gets closer and closer, the higher frequencies become more and more part of what you hear. And if you hear a lightning strike, with that sound like it's ripping the fabric of the space-time continuum, it hits your house. All right, so that's what's going on there. Sound moves through air at about 700 miles an hour, plus or minus depends on the density of the air. But I like easy math, so let's just declare that the sound is moving at 600 miles an hour. Okay, 600 miles an hour is the speed of sound in air. How far does sound go in a minute? Well, at 600 divided by 60. Well, that's how far. I don't know. Who's set up the verbal bath brawl of the night computer? Don't that's not allowed. I don't know, 120 miles. So if it's 600 miles an hour and you're allowed by 60 minutes, right, then sound will move 10 miles an hour. 10 miles in a minute in a minute, right? So sound moves 10 miles in a minute. How many seconds does it take the sound to move one mile? 10 seconds. Oh, six seconds, right? Second. So moves a mile, maybe six seconds so that after a minute, it moves 10 miles. And after an hour, it moves 600 miles. So basically, if you want to know how far away the rain is from you, time, get the time difference between when you see a lightning strike and when you hear it. So you see the flash and the account, one thousand, one thousand, one thousand, one thousand, two thousand, three. So if it's five seconds, let's say, that's almost six seconds. So the storm is about a mile away. A mile away. Yeah, about a mile away. And so, and the real number is 700 miles an hour. So it's, you know, you make a small adjustment, but you get the basic idea, okay? Sound moves a mile every six seconds. And so just for your habits, if you hear the thunder and it never gets closer than that, the rain is not headed towards you. Don't worry about it. Go home, go back to sleep. Nice. If that time delay keeps getting shorter and shorter and shorter. Watch out. Watch out. Yeah, one of these houses. Hit you. You're about to lose your house. Yeah, Dorothy, not in Kansas anymore. There you go. Nice. So a couple of other acoustic things. So for example, a snowflake is very, is highly variegated. Right? It's got six sides. It's got a lot of texture. And if you have snow that's descending, and it's just softly landing on blankets of the, on a surface, okay? Now you have sound. Generally, when you hear someone from a distance, you are relying on the fact that the sound is bouncing off the pavement, off the walls. We don't think often about this, but reflected sound is a big part of how we interact with our world around us. All right. If you have snow everywhere, the surface of the snow is not rigid. It's not highly reflective. In fact, it's highly absorbent. So, particularly for city people, know this. If all of a sudden, the city gets quiet, and you don't hear anything, look out the window. Chances are snowing. Because the sound of the cars, when all the normal sounds that reach you by reflecting off of steel and glass and concrete and cement is no longer reflecting, it's all muffled. Yeah. And so, so this song, the Christmas song Silent Night, Holy Night, whatever other reasons you want to think of it as a Silent Night, if it has just snowed, guaranteed to be more silent than it otherwise would have ever been. Snow, it's nature's soundproofing. And they are soundproofing. Now, when you're walking on snow, okay, as opposed to walking on sunshine. Okay. So, it's just snowed and you're walking on it, okay? And that will normally be a silent exercise, okay, because you're just pressing down snowflakes, because they landed softly, and now you're just sort of compressing them fine. If it's colder, I forgot the temperatures. If it's colder than like 25 degrees, 20, low 20s. If it's definitely, if it's in the teens or lower, if you then step on the snow, okay? The snow says, I will not yield under your boot print. I'm going to hold my shape, because it is cold enough that we are all solid and rigid. And what happens? Because snow crunches. Yeah. Then you crunch on snow. So, if you're filming a movie or if you're observing a scene, and you hear people crunching on the snow, guarantee the temperature of the low 20s are in the teens. Or... Boy, there's a guy in a booth with some cornflakes, and he's just matching the sound to the people walking. It's not correct. The sound studios have all those sweat, the sound effects, and they're... Right. So, that's why snow crunches at cold temperatures, and does not crunch at warmer temperatures. By the way, at the warmer temperatures, your pressure is enough to melt the snow, okay? To bring it immediately below the freezing point. That's a whole other start-talk explainers that we've done. What ice will do under pressure, under pressure. Yeah, so these are some interesting sort of sound things to look out for when this happens. Now, it has been rumored that Aurora, that you can hear Aurora, and I'm not convinced of that. Really? Yeah, yeah. Because it happens 50,000 feet up, in 10 miles away, and farther up in the atmosphere, where the atmosphere is really thin. It is electrical. So, it could be that it's creating other electrical phenomenon in your environment. But to say that you heard sound that comes from that high, I'm not convinced of that. I don't believe it. But people say it, so it's worth it. I best say it. It's things. Yeah. Yeah. It's worth investigating. I think so. Yeah, yeah. And so, let me think. Any other sounds you heard and whether that you wonder about? I mean, aside from the fact that my uncle used to like to make his own sounds and then blame it on me, while we were walking in the cold other than that. Here's another one. The sound of hail hitting. Right? And these are basically like marbles falling out of the sky. I know what that sound is. That is the sound of a call to the insurance that just... So, people say, you know, when do you get hailed most? You get it in the summertime. All right, that's weird. Ice falling out of the sky in the summertime. Well, it's a reminder that the sun is not heating the air. The air is transparent to sunlight. That's why you can see the sun from Earth's surface through the air. And so, the septinosanthulus. That's the azules and Beijing and Mexico City. Right. So, those are inversion layers that... So, they're climatically susceptible to trapping smog. Both of those three areas. He knows they're all in basins. All in Santiago, that's Chile as well. So, here's what happens. The sun heats the ground. The ground heats the air. All right. But if you go high above the ground, it gets very, very cold, very, very quickly, no matter the time of year. All right. But in the summertime, you have the most ground heating. And so, you have the most unstable air columns. So, the biggest, thickest, g-seist, cumulonimbus clouds, which we all learn about in elementary school. The big, puffy ones. Though, you find those in the summertime. And you look at them and you think the cloud is just sitting there. But if you look for long enough, you will see that it is roiling. And in the roiling, there is very highly unstable air rising within it. The more unstable the air is in the upwardly rising columns, the harder it is for whatever is hanging out in there to fall out of the cloud. Because it's kept buoyant by these upwardly moving air columns. Right. So, you first nucleate a little droplet of ice. It wants to fall out and say, no, you're not. And it comes back out and it nucleates with more moisture. Because what is a cloud? It's a big pocket of moisture. Okay. Ophlets. Droplets. Water drops. So, it gathers more moisture. And, ah, no, you're not. And it keeps still in this. It keeps still in this. Until the frozen ball says, you ain't holding me this time. Ah. And that's why all of hell is about the same size. Because it had to get to that size to overcome the highly unstable air columns that were supporting it. And so, so the more turbulent is the air, the louder they will be when they hit the ground. And then there it is. And we always reference the size of hell to some other object, which I find interesting. Notice this. That's a lot of ball size hell. It was baseball size hell. I've never seen anybody talk about hell size golf balls. Right. Maybe it's obvious why, but I don't know. But anyhow, so, Chuck, that's a little bit of the sound of weather. I love it. So, so very cool. Oh, and one other thing. One last thing. You haven't been driving the car and it's raining and it's raining, you know, the whole time you're driving. Yeah, then you come under an overpass. And it's silent. Yes. Okay. Just silent. That's an interesting follow-up because what your brain had done was create the sound of rain as the normal so that when you go under the underpass, it's the absence of rain that you take notice of. See, and that happens in my everyday life where the normal sound is a house full of noise, we're still drinking running around. And when you step out the house, you say, what was that? Oh, it's a fence. When you step out into silence, you wonder, you look around. So silent out here. Which relevant where happened? And oh, my God, did we move to the country? So, there's a word I've seen and it hasn't caught on, but I think it should. It's the sound of the absence of rain under an overpass. Okay. And it's called a downposs. Oh, instead of a downposs, it has downposs. Downposs. Oh, that's a love, I will leave you with that. JP Morgan Payments helps you drive efficiency with automated payments in intelligent algorithms across 200 countries and territories. That's automation driven finance. That's JP Morgan Payments. JP Morgan Internal Data 2024 Copyright 2025, JP Morgan Chase & Company, All Rights Reserve, JP Morgan Chase Bank, and a member FDIC. The positives held non-US branches are not FDIC insured, non-deposit products are not FDIC insured. This is not a legal commitment for credit or services. Availability varies, eligibility determined by JP Morgan Chase. Visit jpmorgan.com slash payments disclosure for details. Fiction. Oh, my goodness. Yes. Fiction. Now, friction usually when people talk about friction, it's bad. All right. You could bring out the WD-40, it's squeaking, it's friction, it's... I can't let it. Let it burn. Fiction burned. Right, right, right. But let me tell you, without friction, life is bad. Without friction, life is we know it would not be possible. Hmm. Fiction is your friend. See, I have lots of missing skin on my knees. Beep, beep, beep. That's a different. So, so friction, I mean, just think about it. If you just sort of put your elbow on the table, right, and you just rest it there. Yes. There's no friction, you would just slide. There'd be nothing keeping your elbow there. That's why I stopped wearing silk shirts. No. So, so, and let's say you wanted to drive your car. You need the friction between your tires and the road so that you will move forward. If there were zero friction between your car and the road, the wheels would just spin. And nothing would happen. Okay. You would go nowhere. You wouldn't be able to start the car, to move the car, slow down the car, stop the car, or even steer the car. All of that requires friction. To walk, to walk, you put a foot down, there is friction there, you press back and your next foot moves forward in advance of it. That required friction. This is why on slippery ice, where there is no friction, you can't walk, you can't run. And you say, oh, and you say, this is bad, put me back on regular ground, what you're really pleading for is, give me some friction. Right. You don't say that, because friction has a bad name. And what do you do when it's cold out and you're not wearing gloves? What do you do? Okay. So, you do that? Okay. Friction is your friend. It is nice. So, would do a whole other thing on friction becoming heat. That's a whole other explainer. That needs its own time for that. But a friction can help get you warm. All right. So, the only thing that really does not use friction is rockets. All other transportation requires friction. Bicycle, trains. Okay. Plains in order to take off. Okay. All of this requires friction. The planes needed to take off. Ah. So, with a rocket, however, by the way, it's why rockets work in space. With there's no air, there's nothing rubbing against anything else. It sends material out the back and it recoils forward. Right. So, all rockets that are accelerating are losing mass in order to do it in a recoil. Whereas, you don't have to lose mass to do it. You just have to press against the earth. Right. Well, Newton told us for every action is an equal and opposite reaction. So, if you are at standstill and you start moving forward, actually something has to start moving backwards. Hmm. And it's communicated that way through friction. So, what happens? You move forward with a certain momentum. What are you pushing against? The ground. The ground. The ground has to move backwards. And it does. So, the entire earth is responding to the fact that you move in one direction. Oh, man. Could we all get together every human being just in one group and start running in one direction? What we speed up the earth? Yes. We can blow it down, depending on which direction. And it has to be do-easter-do-est. Correctly do-est. Yes. So, if everyone lined up and started running do-est, okay? So, that will sort of spin, which way we turn it? Returning this way. So, you have to run and run do-est. And if everybody does that with their scurrying feet, you will speed up the rotation of the earth. What? That is the response of the earth to you propelling yourself forward by way of friction connecting you to the earth itself. The truth with cars, the truth everything. Now, I once did a calculation. And I said, let's get our most powerful rocket engines. Bench mouth them. At the equator where you have sort of maximum torque on the earth. And can we use that to either speed up or slow down the earth? And I did the math on that and it's hopeless. Okay. It's like a net flying full speed into the side of an elephant. And believing the elephant even took notice. Okay. Sorry, confident. Very confident. Very confident. It's a very confident net. In fact, it's less than that. But, by- momentum that we all gave each other by putting ourselves into motion, you can write down that number. Momentum is your mass times your velocity that you gave yourself. Earth's rotation increase or decrease will have changed by exactly that same amount of momentum so that they both cancel. Could you start it out both not moving relative to each other? So if one thing starts moving, the other thing has to recoil the other way so that they balance out. That's physics 101. So if you go forward, earth goes backwards by the exact same total momentum. But earth has so much mass relative to all the mass of the humans that your momentum, which is mass times velocity, that's the only quantity that has to be the same. All right. So all we humans run forward and add up all our mass and get our velocity's added all up. And we got this honkering earth with this really large mass. And it gets a teeny-litty-bitty velocity to balance us out. So if you don't notice it. But you can calculate what that effect is and it is real. It is real. Wow. Excellent. And it's friction. It's all friction. So I just want you to think of friction as a good thing. It's more good than bad. One thing friction does is it slows down things that were put into motion. And our stoddle, not really understanding friction. After all, I got most of his physics wrong, by the way. He's no hero in physics and astrophysics. Thank God he had philosophy. Philosophers like him. And he did important things. But this stuff he could have really checked and he didn't. And so it's before experimental philosophy kicked in. As opposed to thinking philosophy. And so the experimental philosophers Bacon had a whole book just on experiments. He said he conducted, but there's like a thousand experiments in it. And that's what he'd be doing every day for the rest of his life. So I don't think he did them all. But it's a book. We collected them. And so he did the Galileo. Do the experiment if you have an idea. Okay. So. Otherwise, and notice respect Aristotle. You just bullshit. You just, you just think and stuff up that you think should be true. It makes sense to you. We can all do that. In the armchair. So he said things in motion tend to come to rest. Okay. So. That's true. Right. All right. But Galileo said, wait a minute. If I wax the track. You know, I have a thing I roll it down the hill and it stops like here. Now I make it smoother. It stops a little farther away. Make it even smoother. It starts even farther away. And he said, wait a minute. What would happen if there was no friction on this track? Where will it stop? And he concluded that things in motion will tend to stay in. He fed Newton's things in motion tend to stay in motion. It's the opposite of Aristotle. On less act than on by an outsider. No, so I look at that. So Galileo was the bridge between Aristotle and Newton. And doing the experiments by waxing the track. Making it ever more smooth. Reducing the friction coming. That enabled him to establish a fundamental truth about nature. Going beyond just what your life experience is. Look at that. Galileo, the Mr. Miyagi of physics. Who knew? Wax on. Wax on. Wax on. Wax on. So I just want you to appreciate friction. You know, I will not. I know. I still can't get my head around liking friction. But it is necessary. Without friction, everything would just be floating. Would be gliding around. Sliding around. And then you can count through just slide back. By the way, you could push very heavy things. If there's a freight train, I don't care what it weighed. If it's on frictionless tracks. Let's say it's a mag-lab frictionless track. And you have a little handle. Just taking a start pulling. So you can put a force on it. And yes, it's way more mass than you are. So the velocity will be small. But it will have some velocity. So you can just start pushing it. And this is why those strong men and competitions, okay, where they pull with it in the old days. They pull the train with their teeth. Okay. It's because trains are on steel rolling wheels on steel tracks. Which has very low friction. Okay. If you took it off the tracks and let it sit there in the mud. And then I haven't tried to tug the train. That ain't happening. That's kind of funny though. You could pull things that have wheels on them. Because wheels have very low friction in the transmission of the movement of that object to the ground. Because you're not dragging it on the ground. Right. But the wheel itself still needs a little bit of friction in order to not spin. Spin out. That's all. That's so cool. Oh, you know, I have to say. I will never think of friction in the same way. One last thing. Okay. One last thing. When astronauts reenter the atmosphere and they have the burning phase, you know, yes. The flames and they say, all right, we say, oh my gosh, will they survive? This is bad. How could...no, you need that. The astronauts coming out of orbit are going 17,000 miles an hour and they didn't bring fuel to break. Oh. Okay, because all they would have to do, all they would have to do, we don't do this, but what they could do is bring enough fuel. What while you're in orbit at 17,000 miles an hour, because that's orbital speed, turn your ship around and fire it backwards. Right. That will slow you down. And you keep doing that until you have zero velocity, and then you just drop out of the sky. If you drop out of the sky, you're not going to be burning up. Because what's burning up is the kinetic energy of having gone 17,000 miles an hour in the first place. I saw a movie. I think it was one of these Mars movies, one of the earlier ones that became and went, where there's some happening on a platform, and the guy falls off the platform, but it's a stable platform up there above the ground. And as he falls, we see him just burn up. He's like, no, no, the act of falling through the atmosphere alone is not what burns you up. It's the fact that you are going from 17,000 miles an hour to zero, and wait as all the kinetic energy go. There is friction between you and the air molecules passing across your surface. There's also shock waves that communicate as you're going faster than the speed of sound. Shock waves take all this energy that you have and convert it into heat. And then the heat dissipates. And then you fall down out of the sky alive because you have special heat shields that protect you. Uh-huh. There you go. And before we perfected the tiles that we used on the shuttle, we know that the heat shield was astronauts. They weren't really shields. A shield is something that protects you. We call them shields, but that's not what they were. They were like onion layers of burnable material. Oh, so they just burned off exactly, but you had to go through enough of them to get to the, to the crispy center. Where the astronauts are. Where the astronauts are. So, so it turns out coming out of orbit, you need more of these layers than when you come back from the moon. So coming back from the moon, they just make that layer thicker. And then it it ablates and it heats it burns off and goes that takes the heat away. And each as these layers goes, it was a very blunt, effective heat shield. But it's really a shield that dissolves away in the heat. All of that, the friction, the shock waves, and that allows you to not have to take fuel in order to slow down using fuel because you're basically aerobraking. Sweet. That should reentry us. It's a form of aerobraking. That is fascinating. Friction is your friend. As long as I'm trying to tell you, Chuck. And we have to not love friction. Otherwise they can't come home. They can't come home. Or you need fuel to slow down. That's all I'm saying. You want to exploit what you got. And so you just say great. They're burning up their heat shields. That's a good thing. Sweet. All right. I like in it. Chuck. Friction is your friend. All right. I got a new friend to take. That makes one. One, one, one, one, one, one, one, one, one, one, Chuck. Chuck, and his one friend. I got my wife, wife, wife, wife, wife. All right. Neal the grass-ticing here. Your personal after-office is, keep working up. There used to be very little visibility visibility and control in treasury. Today, JP Morgan Payments delivers real-time dashboards and control at your fingertips. That's the power of clarity. That's JP Morgan Payments. Copyright, 2025, JP Morgan Chase & Company. All rights reserved. JP Morgan Chase Bank, NA Member, FDIC. 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