Things You Thought You Knew - Earth’s Spinning Core

What happens if Earth’s core is slowing? Neil deGrasse Tyson and comedian Chuck Nice explore the spinning of Earth’s core, the physics of tire pressure, and the science of toast.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Neil deGrasse Tyson?

  This is StarTalk, a Things You Thought You Knew edition. We have three segments, ready to roll. One of them is on Earth's core. We're gonna follow that with tire pressure. And we're gonna round this out with something we've all done before, but I don't know how much thinking you've ever put into it. And it's the art of making toast. No, it's the physics of making toast on StarTalk.

• 0:32Neil deGrasse Tyson?

  Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:46Neil deGrasse Tyson?

  Chuck.

• 0:47Chuck Nice?

  Yes.

• 0:48Neil deGrasse Tyson?

  Hey, man. People have been talking about Earth's core lately. It's been in the news.

• 0:51Chuck Nice?

  It's been in the news.

• 0:52Neil deGrasse Tyson?

  Yeah.

• 0:53Chuck Nice?

  Clearly, it's slowing down or something. And now we all have, we have to wait for scientists to get into a machine that will burrow to the center of the Earth.

• 1:04Neil deGrasse Tyson?

  And... Where the machine gets stronger as the temperature goes up.

• 1:07Chuck Nice?

  As the temperature goes up, right? You know.

• 1:10Neil deGrasse Tyson?

  Okay, okay.

• 1:11Chuck Nice?

  And they might as well have, uh, they, um, they might as well have found, uh, what's the Wakanda metal? Because it's the same.

• 1:22Neil deGrasse Tyson?

  Vibranium?

• 1:23Chuck Nice?

  Vibranium, yeah.

• 1:24Neil deGrasse Tyson?

  Gets stronger.

• 1:25Chuck Nice?

  And might as well, might as well just be vibranium, because...

• 1:28Neil deGrasse Tyson?

  Okay, so Chuck, do you never leave your couch and watch movies?

• 1:31Chuck Nice?

  Believe it or not, I don't even watch a lot of movies.

• 1:33Neil deGrasse Tyson?

  Yeah, but you're good. You've got some good fluency there.

• 1:36Chuck Nice?

  Yeah, I get to, I remember them all, though. That's why I don't watch a lot. I can never get them out of my head.

• 1:42Neil deGrasse Tyson?

  What's fun is, yes, the latest news is that the core is slowing down.

• 1:47Chuck Nice?

  Right.

• 1:47Neil deGrasse Tyson?

  And so that means we're gonna have to go there and speed it back.

• 1:49Chuck Nice?

  Yeah, exactly.

• 1:53Neil deGrasse Tyson?

  So, let me just back up. I don't claim to be a geologist. Okay. And maybe we should do a whole show on this, I think, and bring in one of my geology colleagues, geophysicist colleagues. But I know Earth is a planet, so let me speak of Earth the way an astrophysicist would speak of Earth. Okay. All right. So when planets form, they are not solid initially. Right. All right. They're first gaseous, and then with enough pressure, they might become liquid. But in any case, once a gravitational field is set up, then heavy things fall to the middle. Right. Because it's not solid yet. Right. Okay? Heavy things fall to the middle. And of all the available ingredients that are just hanging around in the formation of a star system,

• 2:38Neil deGrasse Tyson?

  you get things like, you know, hydrogen and oxygen and silicon and nitrogen and carbon. Right. And you keep going. And as you get to the heavier elements in the periodic table, iron is very common in the universe, and nickel. These ingredients are heavier than silicon and oxygen and carbon. So they fall to the middle. Okay. And what floats on the top are light things like rocks. Okay, there you go. We don't think of SiO2, silicon dioxide, that's a major active ingredient in rocks. We don't think of them as light. We think of rocks as heavy. Right.

• 3:21Neil deGrasse Tyson?

  But they're the lightest thing going on Earth when Earth is forming. And they all float to the top. So our crust is made of light, solid ingredients, and everything below it is made of heavier ingredients. Like a delicious metal pie. Metal pie, exactly. So nature presifts the ingredients.

• 3:46Neil deGrasse Tyson?

  And what's interesting is protoplanets that did this and then solidified, protoplanets might get slammed later on and their bits and pieces break into asteroids. Mm hmm. So some asteroids are made of crustal material, others are made of core material. Got you. So asteroids made of core material are pre-sifted heavy elements. Got you. Such as, like I said, iron and nickel and gold, silver. All these heavy elements are pre-sorted for you if you select a metallic asteroid versus a rocky asteroid. Okay, now there's more of the rocky stuff than of the metallic stuff.

• 4:31Neil deGrasse Tyson?

  So most asteroids are rocky, some asteroids are metallic, and that's what we have out there. So now we have Earth, which was thankfully not broken apart. It has retained its integrity, okay? Oh, but by the way, there are transition zones where the metals are trying to descend and the rocky stuff is trying to ascend, and by then the Earth froze, solidified, froze for its whatever the ingredients are, solidified, and it's stuck in place. And this is how you get like these, or what do you call these? Deposits? These loads, these deposits, okay? They can be trapped in places, frozen out from whatever was going on previously, all right?

• 5:15Neil deGrasse Tyson?

  But the bulk of those materials have separated, just to make that clear. Okay, so now, Earth has retained heat from its past, okay? And so from the formation heat, it is still trying to cool down. Right. All right, Mars is smaller than we are, and so it has more surface compared to its volume, you do the math on that, it turns out to be correct. And the more surface you have, the more you can radiate away your heat. Got you. That's why small animals.

• 5:50Neil deGrasse Tyson?

  Mammals have to eat way more food than larger mammals relative to their body weight because they're radiating away their heat much faster. Right. Because if you look at their surface area compared to their volume, alright? This is why babies need extra protection for their body temperature to protect it. Uh huh. So it's all, we did a whole surface area thing. I remember, I was about to say. Right, it relates to that, okay. So we have, we have less surface area for our volume, it'll take us longer to cool. The consequences of this leftover heat is that we, on the crust, which is cooled solid because it's touching the outer air,

• 6:32Neil deGrasse Tyson?

  we are floating on this sort of plastic liquid mantle. Oh, the lake of fire! Okay, and so we are floating and that's how you get continental drift. And occasionally, that mantle can punch through and you get a volcano. Nice. Okay, so you get earthquakes and volcanoes from a lot of this leftover heat. But let's keep going down. Okay. Down, and now the mixture in the earth is changing. Mm-hmm. And it is so hot, the iron has liquefied. So the outer core of earth is liquid iron. Damn. Okay, that's how hot it is. That's gotta be hot! It's hot, it's about as hot as the sun's surface, basically.

• 7:17Neil deGrasse Tyson?

  Yeah, about 10,000 degrees, you'll melt iron, okay? Take that, Dante!

• 7:25Neil deGrasse Tyson?

  Hell hath no fury like earth's core, how about that? That's right! Alright, so yeah, Dante, you're referring to Inferno, which describes the descent into hell. That's right. Which if you read that and believe it, you would never commit a sin for the rest of your life. It's been pretty devastating. Yes, exactly. Alright, so where are we? So now we have this liquid outer layer, okay. Well, why isn't it liquid all the way through? Because as you keep going further down, the pressure is so high.

• 8:00Neil deGrasse Tyson?

  That it's compactified into a solid.

• 8:03Chuck Nice?

  Look at that.

• 8:03Neil deGrasse Tyson?

  Yes.

• 8:04Chuck Nice?

  So it's just as hot, but the pressure is so great. It will not allow it to melt.

• 8:09Neil deGrasse Tyson?

  Yes.

• 8:10Chuck Nice?

  Oh my God.

• 8:11Neil deGrasse Tyson?

  Yes.

• 8:12Chuck Nice?

  So you have a solid iron core center. That's surrounded by a liquid core outer.

• 8:18Neil deGrasse Tyson?

  This means the solid core is kinda independent of the rest of the planet.

• 8:26Chuck Nice?

  Yes.

• 8:27Neil deGrasse Tyson?

  Because it's only a liquid, it's like lubrication even.

• 8:30Chuck Nice?

  Yes.

• 8:31Neil deGrasse Tyson?

  Think about it that way.

• 8:33Chuck Nice?

  Oh my God, it's like a lava lamp.

• 8:39Neil deGrasse Tyson?

  Yes Chuck, it's exactly like a lava lamp. No, I don't, I forgot what lava, they have these blobs.

• 8:44Chuck Nice?

  Yeah, they got the blobs in there, yeah, yeah.

• 8:45Neil deGrasse Tyson?

  Right, right, right.

• 8:46Chuck Nice?

  Exactly, but go ahead.

• 8:47Neil deGrasse Tyson?

  Okay, so by the way, how do we know all this? You can say, have you been there? How do you know?

• 8:52Chuck Nice?

  Right, exactly.

• 8:52Neil deGrasse Tyson?

  Let me hear it.

• 8:53Chuck Nice?

  So how do you know all this? Like you've been to the center of the Earth?

• 8:56Neil deGrasse Tyson?

  Kind of with our pressure waves, yes.

• 8:59Chuck Nice?

  Oh.

• 9:00Neil deGrasse Tyson?

  For every earthquake.

• 9:01Chuck Nice?

  Uh huh.

• 9:02Neil deGrasse Tyson?

  Once you find the epicenter.

• 9:03Chuck Nice?

  Mm hmm.

• 9:04Neil deGrasse Tyson?

  Which is not too hard, you can triangulate on it. As long as you have earthquake sensors scattered around the world. You can time how long it takes that signal to reach you.

• 9:16Neil deGrasse Tyson?

  In so doing, you can infer the interior structure of the Earth. Because different materials will transmit those waves at different rates than other materials.

• 9:28Chuck Nice?

  So the interior becomes the medium.

• 9:30Neil deGrasse Tyson?

  Correct.

• 9:31Chuck Nice?

  And then you're measuring the wave as it moves through the medium. And that allows you to get the information.

• 9:36Neil deGrasse Tyson?

  You can learn if there are edges between sharp boundaries between one medium and another.

• 9:41Chuck Nice?

  Right.

• 9:41Neil deGrasse Tyson?

  Occasionally, you can have a wave that reflects off of a surface. It's a very complex map that you make from all of these signals when they're done. And it's not just earthquakes. You know what else gives you these data? Underground nuclear tests.

• 9:56Chuck Nice?

  Oh, wow.

• 9:58Neil deGrasse Tyson?

  And those are especially valuable.

• 10:00Chuck Nice?

  Right.

• 10:01Neil deGrasse Tyson?

  Geophysically, because you know exactly where the test occurred.

• 10:05Chuck Nice?

  Right.

• 10:05Neil deGrasse Tyson?

  So there's no, there's less uncertainty in where, where the epicenter is.

• 10:11Chuck Nice?

  You hear that, North Korea? We're on to you.

• 10:15Neil deGrasse Tyson?

  So, so, so you add up all these data and you can reconstruct what the center of the earth, what the entire structure of the earth would be like.

• 10:26Chuck Nice?

  Wow.

• 10:26Neil deGrasse Tyson?

  Okay, without ever having gone there.

• 10:28Chuck Nice?

  That's amazing.

• 10:29Neil deGrasse Tyson?

  Yeah, and these are pressure, basically, sound waves as they go through.

• 10:31Chuck Nice?

  Yeah, exactly. That's crazy.

• 10:33Neil deGrasse Tyson?

  Yeah, so it's pretty cool.

• 10:34Chuck Nice?

  Yeah, it is.

• 10:35Neil deGrasse Tyson?

  It's pretty cool. And by the way, it doesn't reflect too often could forever because it, it slowly damps out and then you have no signal at all.

• 10:43Chuck Nice?

  Right.

• 10:43Neil deGrasse Tyson?

  But there's enough, these things are huge deposits of energy when they occur and the earthquakes and the like. And so it's enough energy to make it through earth and back so that you can, but again, you need sensors. Otherwise, it's a waste, right?

• 10:57Chuck Nice?

  Yeah, exactly.

• 10:58Neil deGrasse Tyson?

  Okay, seismometers, basically, is what you need. Okay. So, another thing, we know from physics that moving electrical charges create magnetic fields.

• 11:13Chuck Nice?

  Right.

• 11:14Neil deGrasse Tyson?

  Okay, Faraday first, notice this.

• 11:19Chuck Nice?

  Mm-hmm.

• 11:20Neil deGrasse Tyson?

  Okay, he, and vice versa, okay? So, so, so you can move a charge, there's a magnetic field that's created around it. You can take a, take a charge, um, move it in a magnetic field and the magnetic field will induce a current in the wire. So, so Faraday did this. So he had a magnetic field, took a wire, moved the wire through the magnetic field and, and an ammeter moved, a needle moved because current. was introduced into the wire. That's how electricity is made today. Exactly. That's what a turbine is, alright? You're moving wires through a magnetic field, creating a current. Wow. And with, uh, with power plants?

• 12:03Neil deGrasse Tyson?

  Everything about a power plant is so that you can sit there and move wires through a magnetic field. So, that's so amazing. It's, it's such a simple, simple concept. It's a simple concept. And that's just been scaled up to this huge form. It's amazing. Feeds the civilization. When Faraday first demonstrated this, and there's just a little meter. It's like, that's cute, Michael. Okay, what's Michael been doing today? Alright, there's a little meter, that's a nice toy. And there's a famous quote, maybe apocryphal, when asked, uh, when he asked for more funding, and he says, "What value is this to the British Crown and, and the British Empire?" And he said, "I don't know, sir, but one day, you will tax it."

• 12:49Neil deGrasse Tyson?

  Wow. That's how you make electricity. Alright, let's get back to the earth. That is also how you talk to any government anywhere. Yes, yes, if you're a scientist and an inventor. Yes. You have this liquid layer, if you have a liquid layer, then the iron can move within that liquid. And iron is an electrical conductor, as we've known since childhood, with the iron filings on the, on the, On the magnets. On the magnets. Yeah. So, when you have elec-, uh, uh, these, um, electrons provided by the iron moving, it creates a magnetic field, and that is the origin of Earth's magnetic field. There you go. That's the origin. That's super cool.

• 13:34Neil deGrasse Tyson?

  Okay, and it's something called a dynamo phenomenon, where you have this circulation, and this continues. And by the way, as is true for the sun, and in many astrophysical objects, the dynamo runs a course of life, where it gets stronger, then it gets weaker, and then it gets stronger again, but with the opposite polarity. Oh, I'm like a phoenix baby. Oh, so we have evidence. From iron that has been spewed forth from volcanoes, that then solidified in place, capturing the magnetic field at the time that the iron, that the field was laid. And we see evidence, every several hundred thousand years of the,

• 14:19Neil deGrasse Tyson?

  of the magnetic field of Earth flipping back and forth.

• 14:24Chuck Nice?

  Oh, look at that.

• 14:25Neil deGrasse Tyson?

  So that's on a cycle, okay? The Sun's magnetic field flips on an 11-year cycle.

• 14:32Chuck Nice?

  Look at that.

• 14:33Neil deGrasse Tyson?

  Okay, Sun has an 11-year cycle and every 11 years it gets strong, uh, uh, hot, more luminosity and less luminosity. But every 11 years it'll do the same thing, but with the, with the poles reversed.

• 14:43Chuck Nice?

  Okay.

• 14:44Neil deGrasse Tyson?

  Okay, so now, let's get back to this. The core basically rotates with the surface of the Earth.

• 14:52Chuck Nice?

  Okay.

• 14:52Neil deGrasse Tyson?

  But occasionally will rotate a little faster.

• 14:55Chuck Nice?

  Alrighty.

• 14:56Neil deGrasse Tyson?

  Slow down, slow, and then a little slower.

• 14:59Chuck Nice?

  Okay.

• 15:00Neil deGrasse Tyson?

  Alright, so we're all comparing it relative to we on the surface. And the recent measurements showed that the solid core of the Earth was trailing behind Earth's surface.

• 15:13Chuck Nice?

  Earth, wait up!

• 15:14Neil deGrasse Tyson?

  Right up, right here! So presumably, this has always been happening. It's not like it's something new. But there's a, there's a periodicity of this that they're estimating to be about 70 years, where it'll slow down, uh, uh, catch up again, overtake us, slow, and, and, and then return. So, so these measurements are affirmations that the core has its own sort of rhythms inside the liquid iron within the rest of the Earth that's rotating around it.

• 15:44Chuck Nice?

  All I know is, this whole thing was worth it just to hear the word "periodicity."

• 15:51Neil deGrasse Tyson?

  Oh, oh.

• 15:52Chuck Nice?

  I mean, I don't know where you pulled that one from.

• 15:54Neil deGrasse Tyson?

  We use that word all the time.

• 15:56Chuck Nice?

  Oh my God.

• 15:57Neil deGrasse Tyson?

  Yeah, the rhythms of the universe. Uh, it, to find them, we track their periodicity.

• 16:03Chuck Nice?

  Oh, look at, let me tell you something. If you gave that to like, um, you know, the people like "always" and "stay free" and all, they, they would love you, because that is, that's a beautiful word.

• 16:17Neil deGrasse Tyson?

  Oh, don't, what's?

• 16:19Chuck Nice?

  I'll tell you right now.

• 16:22Chuck Nice?

  You were

• 16:22Neil deGrasse Tyson?

  You're talking about feminine products?

• 16:24Chuck Nice?

  Yes, I'm saying like, you know

• 16:25Neil deGrasse Tyson?

  That's what you're talking about?

• 16:26Chuck Nice?

  There's so much, there's so much like stigma unnecessarily attached to those Right, right, but instead it's just like, um, hi, yes, I'm, I'm gonna need, um, some periodicity products. Thank you. And I'm, I'm totally cool with that.

• 16:41Neil deGrasse Tyson?

  Okay, alright, thank you.

• 16:42Chuck Nice?

  Mom, send me to the store to get your periodicity stuff.

• 16:45Neil deGrasse Tyson?

  Okay. Alright, so anyway, so we're still trying to figure out what it means that we have this 70-year cycle uh, in the center of the earth.

• 16:53Chuck Nice?

  Right.

• 16:53Neil deGrasse Tyson?

  But right now, earth's magnetic field is weakening.

• 16:56Chuck Nice?

  Okay.

• 16:57Neil deGrasse Tyson?

  And, but we still, it's not, it's not gonna go away in anybody's lifetime, so nothing, uh, would worry about it.

• 17:02Chuck Nice?

  Right.

• 17:03Neil deGrasse Tyson?

  And by the way, there's no, there's no evidence of extinction when the, the, the magnetic field went to zero and then went back up when it flips. There's no, so, because people say, well, the, the magnetic field's protecting us from the dangerous rays of the sun.

• 17:17Chuck Nice?

  Right.

• 17:18Neil deGrasse Tyson?

  And, and maybe, but whatever damage it caused, there's, it's not even a blip in the, in the fossil record, so.

• 17:25Chuck Nice?

  Everybody's gonna be okay.

• 17:27Neil deGrasse Tyson?

  The fish are underwater, they don't, the particles don't hit them ever, right? So fish don't give a c- they don't care.

• 17:33Chuck Nice?

  Everybody's fine, except Harold. He was in the wrong place at the wrong time. Harold, we're sorry.

• 17:41Neil deGrasse Tyson?

  What? That is totally a fish name.

• 17:46Neil deGrasse Tyson?

  The clueless fish named Harold. That is so, the name of the clueless fish.

• 17:51Chuck Nice?

  Who got fried when the poles flipped.

• 17:56Neil deGrasse Tyson?

  That's what you get for trying to use those legs that you should, you should have stayed in the ocean.

• 18:00Chuck Nice?

  Should have stayed in the ocean, Hal.

• 18:02Neil deGrasse Tyson?

  Any time we evolve yet? Alright, we gotta end it there, Chuck.

• 18:06Chuck Nice?

  Alright.

• 18:06Neil deGrasse Tyson?

  So that's my little bit, but we, I'd like to hear this all from the, the mind and the, the brain of a, of a geologist. So we'll try to do a whole show on that.

• 18:14Chuck Nice?

  Yeah, it's all fascinating, I love it.

• 18:15Neil deGrasse Tyson?

  You got it. We gotta take a quick break, but when we come back, more things you thought you knew. We're gonna be talking about tire pressure.

• 18:32Speaker 02

  Hey, I'm Roy Hill Percival and I support StarTalk on Patreon. Bringing the universe down to earth. This is StarTalk with Neil deGrasse Tyson.

• 18:48Neil deGrasse Tyson?

  Welcome back to StarTalk, Things You Thought You Knew, Segment Two. Chuck, we're going to talk about tire pressure. All right, are you, are you, are you ready for tire pressure?

• 19:00Chuck Nice?

  I'm really not.

• 19:03Chuck Nice?

  But this is, you know, where, hey, listen, I feel like this. At this point, you know, we done paddled out. It's time to ride the wave. That's the way I feel.

• 19:15Neil deGrasse Tyson?

  We're out there, just let's do it. Bring it on.

• 19:18Chuck Nice?

  We're out here. You say tire pressure, I'm like, you gotta be zen enough to go ahead and jump up. It's time to get up and surf this wave.

• 19:26Neil deGrasse Tyson?

  All right, let's do it. So tire pressure, first of all, if you have a tire with, quote, no air in it, of course, there's air in it because the atmospheric air is in it. Okay? And atmosphere has its own pressure. And this is the weight of a column of air from Earth's surface all the way up to the edge of the atmosphere. If you had found a way to weigh this, I think we might have talked about this in another explainer. But if you, if you have like one square inch or one square anything, but one square inch and have weighed that column of air, it will weigh 14.7 pounds. Okay? And the way air works, fluids work, is that pressure, I would say, yes, it's sitting on the scale,

• 20:08Neil deGrasse Tyson?

  but that pressure manifests in every direction because the molecules are vibrating in every direction. So, so right now, I have 14.7 pounds per square inch on one side of my hand and on the other, above, bottom, and so everything's all equaled out. So I don't even notice it.

• 20:26Chuck Nice?

  That's why you're not getting crushed by your 14-pound air. Just doesn't make a difference because it's pushing down on you and pushing up. It's even.

• 20:36Neil deGrasse Tyson?

  Whereas if I have a suction cup and I press out the air that would otherwise be balancing it, if I press it out.

• 20:48Chuck Nice?

  Yeah.

• 20:48Neil deGrasse Tyson?

  So now I say, lift up the suction cup. You say, I can't, it's sucking me down. No, it's not. Why can't you pick up the suction?

• 20:54Chuck Nice?

  14.7 pounds.

• 20:56Neil deGrasse Tyson?

  Per square inch pressing down.

• 20:58Chuck Nice?

  Per square inch is pushing it down. It's really not sucking anything.

• 21:03Neil deGrasse Tyson?

  Suction cups don't suck.

• 21:04Chuck Nice?

  They don't suck. They got a bad rap for so long.

• 21:08Neil deGrasse Tyson?

  They don't suck.

• 21:10Chuck Nice?

  They don't suck.

• 21:11Neil deGrasse Tyson?

  So if you had 10 square inches of area on this, on the suction cup, I can ask you how much force would it take to pull the suction cup off the surface?

• 21:22Chuck Nice?

  So I gotta go 10 square inches times 14.7 pounds per and then push back in that opposite direction?

• 21:28Neil deGrasse Tyson?

  That gets you 147 pounds. So if you can pull 147 pounds or more, it pops right up. Or you could cheat and pop open a little curl in the edge.

• 21:39Chuck Nice?

  And then let nature.

• 21:40Neil deGrasse Tyson?

  Air slips in and then it just comes off.

• 21:42Chuck Nice?

  Right.

• 21:43Neil deGrasse Tyson?

  Letting nature help you out. Okay, so the point is, if you fill a tire to what we call 10 pounds per square inch, that's 10 pounds on top of the air pressure that's already in there. That's all I'm saying.

• 21:57Chuck Nice?

  Right.

• 21:58Neil deGrasse Tyson?

  All right, so first of all, just lay that out. All right, so now, have you noticed, or perhaps not, that on bicycle tires, the thinner, the skinnier the tube?

• 22:13Chuck Nice?

  Yes.

• 22:14Neil deGrasse Tyson?

  The what?

• 22:16Chuck Nice?

  The less air you should keep putting in it once it gets hard, because it will pop.

• 22:22Neil deGrasse Tyson?

  Okay.

• 22:23Chuck Nice?

  I'm telling you.

• 22:24Neil deGrasse Tyson?

  From experience, okay?

• 22:27Neil deGrasse Tyson?

  Okay, if you look at the ratings of thin tires, in essentially every case, depending what they're made of, but in every case, they have a higher pounds per square inch rating than the bigger tires. Okay? Higher.

• 22:43Chuck Nice?

  Okay.

• 22:43Neil deGrasse Tyson?

  Period.

• 22:44Chuck Nice?

  I don't, I didn't know that, to be honest.

• 22:45Neil deGrasse Tyson?

  Okay, so now watch.

• 22:46Chuck Nice?

  This is, this is the first I'm ever hearing.

• 22:48Neil deGrasse Tyson?

  Because you never, you gotta pay attention, okay?

• 22:51Chuck Nice?

  Well, no, I'm gonna tell you why. Because I come from the times when you would fill your tire and then you just push down on it. And if you can actually push it and flatten it, you're like, now put some more air.

• 23:05Neil deGrasse Tyson?

  Oh, that was how you measured.

• 23:07Chuck Nice?

  Yeah. And then once you couldn't do that, you'd be like, all right, it's time to go.

• 23:11Neil deGrasse Tyson?

  Yeah, you want to use a gauge, okay?

• 23:13Chuck Nice?

  Right, exactly, all right.

• 23:15Neil deGrasse Tyson?

  So, and the gauge is calibrated to not count air pressure. All right, so that's how they work. All right, so now watch. Here you go. So, um, the pounds per square inch

• 23:31Neil deGrasse Tyson?

  equals

• 23:35Neil deGrasse Tyson?

  the pounds per square inch of your tires in contact with the road, okay? You sitting on your bicycle and the bicycle has tires and the tires are in contact with the road. Obviously, the heavier you are, the flatter the tire is gonna look, okay? True. Okay, you know this. Well, yeah. Why does the tire flatten? If you're heavier, why, why does it do that? I'm gonna tell you why. Because at all times, the pressure inside the tire per square inch times the square inches of tire in contact with the road

• 24:22Neil deGrasse Tyson?

  has to equal your weight plus the weight of the bicycle.

• 24:26Neil deGrasse Tyson?

  At all times. Wow. At all times. Okay.

• 24:31Neil deGrasse Tyson?

  Okay? So. So, alright, so if I have a big tire, like a kid's tire, okay? If I have one of those kind of tires and it's huge, it might take thirty pounds per square inch, that's not uncommon, okay? Thirty, twenty to thirty pounds per square inch. And there's a square inch of it in contact in the back and a square inch in contact with the front. Add those up, it is holding up sixty pounds. That could be the weight of the bicycle plus the weight of the kid. Okay, you put a heavy kid on there, the bicycle has to hold up more weight against the air pressure in the tires. So the tires flatten a little more, adding more surface area.

• 25:16Neil deGrasse Tyson?

  Okay? Adding more area, so that now you go, go the air pressure times the, the, the square inches in touch with the ground and now that'll equal the weight of the heavier kid. Okay, so I, I'm heavy, alright? I'm two hundred and sixty pounds right now, okay? Alright, so now, I ride a bicycle with very narrow tires.

• 25:42Neil deGrasse Tyson?

  The air pressure in those tires is 130 pounds per square inch. 130 pounds, okay, per tire. So watch what happens. I deflate it to that amount and those tires will flatten to slightly more than a square inch per tire.

• 26:01Neil deGrasse Tyson?

  Because it's my weight plus the weight of the 22 pound bicycle. It's got to hold up 280 pounds. So it's going to flatten slightly more than a square inch on each. And that is my, that is my tire. Okay.

• 26:16Chuck Nice?

  Okay.

• 26:18Neil deGrasse Tyson?

  So farm tractors have huge tires.

• 26:24Chuck Nice?

  Right.

• 26:25Neil deGrasse Tyson?

  Huge tires. In that way, they put relatively low air pressure in them. That way, when the tires roll over the crops, it does minimal damage.

• 26:38Chuck Nice?

  Right, because you're not digging in.

• 26:42Neil deGrasse Tyson?

  It's spread out. The pressure, okay?

• 26:47Chuck Nice?

  Brilliant.

• 26:47Neil deGrasse Tyson?

  You can still hold up the tractor. If you, if you get enough area coming down. Otherwise, you'd be leaving deep tracks in the road and you can't have that, not in your farm.

• 26:57Chuck Nice?

  Ah, it's like dune buggies. They all have big, giant, wide, like balloon tires.

• 27:02Neil deGrasse Tyson?

  So, so, well, that one is to increase traction on sand, okay?

• 27:07Chuck Nice?

  Yeah, but they don't dig into the sand.

• 27:09Neil deGrasse Tyson?

  But they don't dig into the sand, correct. And so, so tire pressure is all about how much weight are you holding up? And they will tell you in your car, if you're going to carry a heavy load, increase the air pressure in your tires so that your tires don't flatten out.

• 27:27Chuck Nice?

  Right.

• 27:27Neil deGrasse Tyson?

  If you increase the pressure from, let's say, you know, 35 pounds to 45 pounds per square inch, that gets you extra support in all of your tires. In a typical car, you know, how wide is a, is a tire? You know, it might be a foot, you know, nine inches.

• 27:45Chuck Nice?

  20, 18 inches is a typical tire.

• 27:47Neil deGrasse Tyson?

  No, no, not across.

• 27:50Chuck Nice?

  Yeah.

• 27:50Neil deGrasse Tyson?

  What are you, riding the Indy 500?

• 27:53Chuck Nice?

  Eighteen inches?

• 27:54Neil deGrasse Tyson?

  Are you s- yeah, okay. All right. I'll give it to you. I don't know. I mean, we're both city people, so I don't, you know.

• 28:01Chuck Nice?

  Uh, well, yeah, I mean, I, I drive an SUV, though.

• 28:03Neil deGrasse Tyson?

  Oh, okay, fine.

• 28:05Chuck Nice?

  They're sitting on eighteens. It's an SUV. So, you said car, and I'm really not thinking car.

• 28:11Neil deGrasse Tyson?

  Fine. I said, so a car might be that-

• 28:14Chuck Nice?

  And it's not electric, and I'm, I'm very ashamed, but I'm buying an electric car, so. I know you already have one.

• 28:19Neil deGrasse Tyson?

  Eventually.

• 28:20Chuck Nice?

  But I'm, I'm late to the game.

• 28:22Neil deGrasse Tyson?

  You can do this experiment at home. Go look at how much of your tire is touching the ground. Measure that, okay? Front to back and then across the width. So you'll get two measurements. It might be like five inches, uh, front to back, flattening on the ground, and then measure the, the width of the tire. Multiply those numbers by each other. That's the square inches per tire. Multiply that by four, and that's gonna give you the weight of your car.

• 28:51Chuck Nice?

  Get out of here. That's pretty wild. I mean, that makes sense, just from what you just said. Uh, there's only one problem. I do not give a damn how much my car weighs.

• 29:04Neil deGrasse Tyson?

  Chuck, do it for science, okay?

• 29:07Chuck Nice?

  Oh, I will do it for science.

• 29:09Neil deGrasse Tyson?

  You should get somewhere between, you're in SUV, somewhere between fifteen hundred pounds and a ton, two thousand, something like that.

• 29:16Chuck Nice?

  Okay.

• 29:16Neil deGrasse Tyson?

  But all, just by measuring the square inches. So, well, sorry, you have to know what your tire pressure is first, okay?

• 29:23Chuck Nice?

  Right.

• 29:23Neil deGrasse Tyson?

  And then get your square inch in the sidewall. Or, or maybe if you're a modern car, it tells you on the, on the-

• 29:30Chuck Nice?

  Yeah, they can tell you on the dashboard.

• 29:32Neil deGrasse Tyson?

  And so, you got four tires and get the area. So it's front to back in contact and then the width. Multiply those two numbers, then multiply by four. There you, and multiply by your air pressure. That's the weight of your car.

• 29:45Chuck Nice?

  And that's the weight of your car.

• 29:47Neil deGrasse Tyson?

  It's a way to weigh your car without going to a scale. Cause your, your tires are doing it all by themselves.

• 29:53Chuck Nice?

  And now, all I need to do is figure out the calculation to put Aunt Gail and Uncle Daryl in the backseat.

• 30:02Neil deGrasse Tyson?

  That's a different calculation. So it'll either flatten the tires some more, so then the car is giving itself away to hold them up, or you increase the air pressure so that at the same area in contact with the ground, it holds them up. Okay?

• 30:16Chuck Nice?

  That's where, yeah.

• 30:16Neil deGrasse Tyson?

  And generally, they tell you to increase the air pressure, because it's better for gas mileage and things.

• 30:20Chuck Nice?

  Yeah, right on.

• 30:22Neil deGrasse Tyson?

  All right, you got it, dude.

• 30:23Chuck Nice?

  I love it. That's cool. There's math in everything in the world. It really is. I gotta tell you, I was worried when you said tire pressure. I really was. I was worried, man.

• 30:37Neil deGrasse Tyson?

  We gotta take a quick break, but when we come back, Chuck and I are gonna talk about the physics of toast on StarTalk.

• 30:57Neil deGrasse Tyson?

  We're back, StarTalk, Things You Thought You Knew Edition, Segment 3. Chuck, we're gonna talk about the physics of making toast.

• 31:07Chuck Nice?

  Okay. All right.

• 31:12Chuck Nice?

  I'm just saying. You know, sometimes when you bring these up, man, I feel like you're just, like you're punking me, you know what I mean? Because I'm like, I'm just like, let me just see if I, what I can get Chuck to go along with.

• 31:25Neil deGrasse Tyson?

  Astrophysics of making toast.

• 31:26Chuck Nice?

  It's like, because you know, it's like Neil deGrasse Tyson, right? World-renowned scientist and science communicator. Chuck, I'd love to talk to you about something scientifically relevant. Oh, Neil, please do tell. Let's talk toast. What?

• 31:42Neil deGrasse Tyson?

  All right, so, here's the deal.

• 31:43Chuck Nice?

  Okay.

• 31:44Neil deGrasse Tyson?

  All right, and I don't know if you ever paid attention to what's going on inside a toaster.

• 31:48Chuck Nice?

  Okay.

• 31:48Neil deGrasse Tyson?

  All right?

• 31:49Chuck Nice?

  Listen.

• 31:49Neil deGrasse Tyson?

  But it's fascinating.

• 31:51Chuck Nice?

  I have smoked a lot of weed. I have been high out of my mind. I have never looked at the toaster and went, I wonder what's going on in there.

• 32:03Neil deGrasse Tyson?

  All right, here's the thing.

• 32:05Chuck Nice?

  Okay.

• 32:06Neil deGrasse Tyson?

  Here's the thing. A toast, if you're gonna toast fresh bread.

• 32:09Chuck Nice?

  Okay.

• 32:10Neil deGrasse Tyson?

  Okay? It will spend most of its time in the toaster, most of the time not browning.

• 32:19Chuck Nice?

  Okay, and is this fresh white bread? Because that would make sense.

• 32:27Neil deGrasse Tyson?

  Yes, it's easier to see the browning of white bread. So this is a white bread example.

• 32:31Chuck Nice?

  But can you blame it? Because let's be honest, in bread society, you know, white bread hasn't the best.

• 32:38Neil deGrasse Tyson?

  They got the best. But the seven grain blended model is coming along, okay? So here's the thing.

• 32:45Chuck Nice?

  And let me tell you something. Pumpernickel, there goes some property values in the bread box.

• 32:52Neil deGrasse Tyson?

  I forgot all about Pumpernickel. That's some dark ass bread right there.

• 32:56Chuck Nice?

  Tell me right now.

• 33:00Neil deGrasse Tyson?

  Okay.

• 33:01Chuck Nice?

  Oh, go ahead. Never mind. I'm about to get us in trouble. I'm gonna stop.

• 33:04Neil deGrasse Tyson?

  All right. So if you if you observe the bread.

• 33:08Chuck Nice?

  Yes.

• 33:08Neil deGrasse Tyson?

  Most of the time, 90% of the time, I didn't know exactly, but it's very high percent of the time it's in the toaster, it doesn't change color at all.

• 33:16Chuck Nice?

  Oh, my God.

• 33:18Neil deGrasse Tyson?

  Okay. Because it can't change color as long as it's moist.

• 33:27Chuck Nice?

  Okay.

• 33:28Neil deGrasse Tyson?

  Because the highest temperature you can heat the bread is 212 degrees, and that's not hot enough to toast the bread.

• 33:36Chuck Nice?

  I got you. I mean, that really does make sense. It's like it's like trying to start a fire with green kindling.

• 33:43Neil deGrasse Tyson?

  You can't.

• 33:44Chuck Nice?

  Right.

• 33:44Neil deGrasse Tyson?

  You can't.

• 33:45Chuck Nice?

  Can't do it.

• 33:45Neil deGrasse Tyson?

  In fact, if you put a green log on an already established fire, the log is not going to ignite. You know what's gonna happen? It's gonna hiss out all the moisture for the next hour.

• 33:55Chuck Nice?

  Yep.

• 33:56Neil deGrasse Tyson?

  All right? Because the log can't get hotter than the highest temperature that water can get. And the water that's in the log tops out at 212 degrees. So you're gonna have a 212 degree log until there's no water left.

• 34:08Chuck Nice?

  That's cool.

• 34:08Neil deGrasse Tyson?

  And then it'll ignite.

• 34:10Chuck Nice?

  That's right. Oh, wow.

• 34:12Neil deGrasse Tyson?

  Okay. So your toast in the toaster, if you keep looking at it, it's gonna be your white toast. It's gonna be white and white and white. And what the heat is doing, it's like, get out of there, you water molecules.

• 34:23Chuck Nice?

  Right.

• 34:23Neil deGrasse Tyson?

  Get out, get out. And it's only doing it to the top edge, not to the middle, because the heat is only hitting the top, the outer edges, right?

• 34:29Chuck Nice?

  Right.

• 34:30Neil deGrasse Tyson?

  So.

• 34:30Chuck Nice?

  So the heat is like the Black Toast Matters movement. Yeah.

• 34:38Neil deGrasse Tyson?

  Chuck, you you need race counseling, okay?

• 34:43Neil deGrasse Tyson?

  All right.

• 34:44Chuck Nice?

  So go ahead.

• 34:45Neil deGrasse Tyson?

  All right, so, once all of the moisture on that outer edge of the bread has evaporated.

• 34:52Chuck Nice?

  Right.

• 34:53Neil deGrasse Tyson?

  It can now toast the bread. By by breaking apart the the the the bread molecules, the proteins and the and the carbohydrates, revealing the carbon, the carbon is black, okay? If you leave the bread in too long, it's completely black, all right? But you have all this golden tip. That all happens in like the last minute that your toaster's in there. Because it took all the rest of that time to heat up the water and evaporate it.

• 35:21Chuck Nice?

  That is pretty doggone cool, to be honest, and I I got a little excited when you said that, because I've never considered it. However, I don't have a toaster. I have a um, a toaster oven. I don't use.

• 35:39Neil deGrasse Tyson?

  Okay, so, okay, so in in the oven, any oven, if you're gonna use a broiler.

• 35:43Chuck Nice?

  Right.

• 35:43Neil deGrasse Tyson?

  The same thing.

• 35:44Chuck Nice?

  Same thing.

• 35:45Neil deGrasse Tyson?

  You you layer the bread.

• 35:46Chuck Nice?

  Exactly.

• 35:47Neil deGrasse Tyson?

  And you check and you're checking it.

• 35:48Chuck Nice?

  That's right.

• 35:48Neil deGrasse Tyson?

  And you keep checking it, and you say, it's not making progress. Let me go away for five minutes. No, because the moment the moisture's gone, that sucker browns in instance. Okay? So it's not a linear, it's not a linear phenomenon.

• 36:03Chuck Nice?

  No, it's kind of like, if if it were a graph, it would bump along the bottom, and then all of a sudden it shoots straight up, almost.

• 36:09Neil deGrasse Tyson?

  Yeah, almost straight up.

• 36:10Chuck Nice?

  Almost straight up. So, and I know this because, just the other day, when you, it's so weird now, I can't believe that I'm recalling this, I said, what's taking this toast so damn low?

• 36:26Chuck Nice?

  And then I turned, I went into the refrigerator, I pulled out some butter and um, fig spread. And I went back, and the toast was brown.

• 36:41Neil deGrasse Tyson?

  There it is.

• 36:42Chuck Nice?

  So, that is so wild.

• 36:44Neil deGrasse Tyson?

  You you lived this experience.

• 36:45Chuck Nice?

  I lived this experience.

• 36:46Neil deGrasse Tyson?

  It's it's it's also why you can boil water in a paper cup.

• 36:52Chuck Nice?

  Okay.

• 36:54Neil deGrasse Tyson?

  Okay, and I've done this experiment many times, so.

• 36:56Chuck Nice?

  So wait, you, yeah, I mean, yeah, you just drop the paper cup inside the pot of boiling water, okay?

• 37:01Neil deGrasse Tyson?

  And you now. No, no, no, that's, that's not what it, no, so you can, you can take a paper cup. And you have to be careful about this because some paper cups have rims on the bottom.

• 37:10Chuck Nice?

  Yes.

• 37:10Neil deGrasse Tyson?

  That are not actively touching the water on the inside. That will burn, okay? But if you have a wide enough bottom and you have like a Bunsen burner, remember these?

• 37:19Chuck Nice?

  I remember.

• 37:20Neil deGrasse Tyson?

  You put the flame on the paper cup in the bottom. If the paper cup has water in it, what is the hottest temperature the paper can get? The temperature of water. Okay, and so it'll sit there and boil the water. And it'll keep boiling the water until all the water evaporates. Then your paper cup burns. This is why it's so hard to burn someone at the stake. You think, oh, let me just ignite you, this is very medieval here.

• 37:44Chuck Nice?

  I was about to.

• 37:44Neil deGrasse Tyson?

  Let's put you on the stake and just ignite you. You can't just ignite, okay? You have all this liquid in you.

• 37:50Chuck Nice?

  Right, the real, the real reason why this is very difficult to do is because we have laws against that now.

• 37:55Neil deGrasse Tyson?

  That's why.

• 37:56Chuck Nice?

  That's the real reason.

• 37:58Neil deGrasse Tyson?

  That's the actual reason, it's difficult. Thank you, let me get out of my medieval.

• 38:05Neil deGrasse Tyson?

  So what they would do, especially the Catholic Church, to make sure you would burn, that sometimes they would burn you upside down. And that way, um, will control the blood. Or the blood would drain, and as the blood drains, then you have no liquid left in you and you burn faster.

• 38:21Chuck Nice?

  Oh.

• 38:21Neil deGrasse Tyson?

  Or you can burn in other directions where you retain the blood. Because if you don't want the blood come out, there's some other religious ritual where the, the whole person has to be burned, including their blood, but then the blood has to still evaporate.

• 38:35Chuck Nice?

  Oh.

• 38:35Neil deGrasse Tyson?

  Before any, though you'll die before that happens, of course. But in terms of igniting the body.

• 38:40Chuck Nice?

  Yeah.

• 38:40Neil deGrasse Tyson?

  Thing, it just doesn't simply happen that way. And this is sped up if you have fast moving air, hot air across the, the food.

• 38:49Chuck Nice?

  Yes.

• 38:50Neil deGrasse Tyson?

  This, this is like a wind heat factor.

• 38:52Chuck Nice?

  Mm hmm.

• 38:53Neil deGrasse Tyson?

  The op, we have a, we have a, a, an explainer on wind chill factor and wind heat factor.

• 38:58Chuck Nice?

  Yes.

• 38:58Neil deGrasse Tyson?

  Okay? Because if it's cold and the wind is blowing, you feel colder.

• 39:02Chuck Nice?

  Colder, right.

• 39:03Neil deGrasse Tyson?

  If it's hot and the air that's blowing is hotter than your skin temperature, you'll feel hotter.

• 39:08Chuck Nice?

  Right.

• 39:09Neil deGrasse Tyson?

  Okay, so if you put food in, let's say, an air fryer.

• 39:13Chuck Nice?

  Yes.

• 39:14Neil deGrasse Tyson?

  What does that mean, okay? So they are gonna brown your food. Fast because they're moving hot air across and they're evaporating any possible moisture on that surface. And the faster the wind goes, the faster you'll evaporate it. And the faster you can get to the browning.

• 39:32Chuck Nice?

  Can't live without an air fryer, I'm sorry. It's amazing. They're wonderful.

• 39:36Neil deGrasse Tyson?

  Yeah, they they're really air toasters.

• 39:38Chuck Nice?

  Yes.

• 39:38Neil deGrasse Tyson?

  Because, uh, you know, unless the the the surface is sprinkled with oil. And then the oil will fry the, you know, you can heat the oil. So you're you're still oil frying. But you're using air to heat the oil to fry the food.

• 39:55Chuck Nice?

  Right.

• 39:56Neil deGrasse Tyson?

  But if it didn't have any oil, it's just a fast toaster.

• 39:58Chuck Nice?

  Yeah, exactly.

• 40:01Chuck Nice?

  You mean I spent $400 on a toaster? Yes, you did. Yes, you did. You did indeed.

• 40:11Neil deGrasse Tyson?

  So that's everything you wanted to know about toast and why it's not a linear process.

• 40:15Chuck Nice?

  Well, that was fun.

• 40:17Neil deGrasse Tyson?

  I'm. Oh, and what don't you do? Ooh, ooh, ooh. Dude, you can do this experiment.

• 40:20Chuck Nice?

  Okay.

• 40:20Neil deGrasse Tyson?

  Take a take a slice of bread.

• 40:22Chuck Nice?

  Okay.

• 40:22Neil deGrasse Tyson?

  Let leave it out until it just gets hard.

• 40:25Chuck Nice?

  A little crusty.

• 40:26Neil deGrasse Tyson?

  Okay.

• 40:26Chuck Nice?

  Right.

• 40:26Neil deGrasse Tyson?

  Cr- just leave it out.

• 40:28Chuck Nice?

  Just leave it out.

• 40:28Neil deGrasse Tyson?

  Okay, we'll get crusty, it'll just get get hard.

• 40:30Chuck Nice?

  Yeah.

• 40:31Neil deGrasse Tyson?

  It's no longer squishy. And then you have another one that's squishy that you just took out of the bag.

• 40:35Chuck Nice?

  Okay.

• 40:36Neil deGrasse Tyson?

  They're both at the same temperature.

• 40:39Chuck Nice?

  Right.

• 40:40Neil deGrasse Tyson?

  Okay, now put them both in the in your in your toaster oven. We're both in the toaster and the one that had the the lost moisture will toast 10 times faster.

• 40:50Chuck Nice?

  Okay.

• 40:51Neil deGrasse Tyson?

  Oh, yeah.

• 40:52Chuck Nice?

  Oh, there you go. So, yeah, and it's it's already on its way to being toast.

• 40:57Neil deGrasse Tyson?

  That's right.

• 40:58Chuck Nice?

  Yeah. You leave it out. Well, why you keep leaving the bread out? I'm toasting the bread, man.

• 41:03Neil deGrasse Tyson?

  I'm toasting the bread.

• 41:04Chuck Nice?

  I'm toasting the bread.

• 41:05Neil deGrasse Tyson?

  Pretoasting.

• 41:07Chuck Nice?

  It's a pretoast.

• 41:08Neil deGrasse Tyson?

  And one other thing, a reminder of how surface deep the color is.

• 41:14Chuck Nice?

  Okay.

• 41:14Neil deGrasse Tyson?

  Because it's only what that sort of radio of energy can touch. And anything's behind anything else is not seen in your toaster thing, all right? So a reminder of that is if you happen to burn the toast.

• 41:25Chuck Nice?

  Right.

• 41:26Neil deGrasse Tyson?

  You just take a bread knife or or a knife, not, you know, a knife and scrape off

• 41:30Chuck Nice?

  Mm hmm.

• 41:31Neil deGrasse Tyson?

  the black.

• 41:31Chuck Nice?

  Right.

• 41:33Neil deGrasse Tyson?

  And then there's like, and you can salvage many a burnt toast that way.

• 41:37Chuck Nice?

  Or you could just accept the fact that it is black and enjoy it for its beautiful blackness. You could do that as well.

• 41:51Neil deGrasse Tyson?

  Yeah, Chuck totally, definitely needs race therapy.

• 41:53Chuck Nice?

  I know, I can't help it.

• 41:59Neil deGrasse Tyson?

  So, so maybe there's more than you ever cared to know about making toast.

• 42:02Chuck Nice?

  No.

• 42:02Neil deGrasse Tyson?

  I just thought I'd put that, the thermodynamics of toasting.

• 42:06Chuck Nice?

  That is awesome. We got a title just that, the thermodynamics of toasting.

• 42:11Neil deGrasse Tyson?

  Okay, of toast. Yeah, and so, and the takeaway here is, however long you're staring at the unbrowned toast, let that not be the measure of how much longer you have to wait.

• 42:23Chuck Nice?

  Yes. I know this firsthand, absolutely.

• 42:27Neil deGrasse Tyson?

  Yeah, yeah, you got it. All right, that's all we had time for, Chuck.

• 42:30Chuck Nice?

  Oh, that was great, that was great, that was great.

• 42:32Neil deGrasse Tyson?

  That was yet another edition of Things You Thought You Knew from StarTalk. Chuck, always good to have you. I'm Neil deGrasse Tyson, your personal astrophysicist. As always, bidding you to keep looking up.