Speaker 1: Hey, Daniel, how do you feel about skepticism. I don't know,
Speaker 1: I'm a little skeptical of it. Well, I mean, do
Speaker 1: you think it's always a good thing to be asking questions?
Speaker 1: I'm always in favor of questions. I mean, that's definitely
Speaker 1: how we got where we are, and that's how we
Speaker 1: learned so much about this incredible universe. But you know
Speaker 1: there are caveats. Okay, so I got a good one
Speaker 1: for you. Do you believe the Earth is round? Actually
Speaker 1: know that Earth is not round? What? Are you one
Speaker 1: of those flat earthers? No? No, No, those people are crazy.
Speaker 1: There are a lot of them out there. I know
Speaker 1: there are flat earthers all around the globe, all around
Speaker 1: the globe, not on top or below the globe exactly. Well,
Speaker 1: what's your take from a physicist? The official answer is
Speaker 1: Earth round or flat? It's a false choice. The answer
Speaker 1: is neither. Stay tuned and find out. Hi. I'm Jorge,
Speaker 1: I'm a cartoonists and the creator of PhD Comics. Hi,
Speaker 1: I'm Daniel Whiteson. I'm a particle physicist by day and
Speaker 1: a podcaster by any other time. And welcome to our podcast.
Speaker 1: Daniel and Jorge explain the Universe, a production of I
Speaker 1: Heart Radio, in which we try to explain crazy things
Speaker 1: about the universe, sometimes things really far away, sometimes things
Speaker 1: in our neighborhood, sometimes things right under our feet. I'm sorry.
Speaker 1: We try to tackle big questions, small questions, Questions you
Speaker 1: think you know the answer to, but maybe the universe
Speaker 1: has a way to surprise you. That's right. Round questions,
Speaker 1: flat questions, square questions, squiggly questions, and squishy questions. We
Speaker 1: love all the questions. Questions are our business. Who I
Speaker 1: like that as our company? Mottel, that's right. Do we
Speaker 1: have a company, Daniel, Um, we should make one. Yes,
Speaker 1: We're in a good company. All right. Well, so today
Speaker 1: we're tackling a question that obviously humans have been um
Speaker 1: had been struggling with for a long time, and I
Speaker 1: think for pretty much the last couple of centuries, people
Speaker 1: think we know that the answer to right. That's right.
Speaker 1: This is the kind of question people ask, and it's
Speaker 1: a kind of question it can be hard to answer
Speaker 1: immediately just by looking at what's around you. But it's
Speaker 1: a fun question because it's the kind of question that
Speaker 1: you know, sort of the beginning of cosmology. It's like,
Speaker 1: let's try to get a larger scale understanding. Let's try
Speaker 1: to understand not just the world I live in every
Speaker 1: day when I walk to my friend's house or go
Speaker 1: to the river and wash my food, but like the
Speaker 1: larger context where we find ourselves and how it all works.
Speaker 1: So the beginning of that intellectual struggle, yeah, kind of
Speaker 1: asking like what's beyond what we can see and touch? Right?
Speaker 1: That's right? How does it all fit in? Right? Like,
Speaker 1: you know the picture frame that my life lives in.
Speaker 1: Am I a tiny little dust mode in the corner?
Speaker 1: Am I in the center of it? Um? How big
Speaker 1: is that picture frame? You know? This? These are interesting questions,
Speaker 1: and I wonder sometimes like who were the first people
Speaker 1: to think of those questions? You know, as humanity emerge
Speaker 1: from you know, pre humans into an intelligence, Like when
Speaker 1: did people post humans? When did people first start to
Speaker 1: ask these kinds of questions? You know, how big is
Speaker 1: the earth? What is its shape? Um? You know, where
Speaker 1: is the sun? All these kind of questions about our
Speaker 1: basic cosmology? Yeah, Like who do you think was the
Speaker 1: first sentient being? That just kind of wondered, like if
Speaker 1: I keep going in that direction, what's going to happen?
Speaker 1: Or if I shoot straight up, what's going to happen?
Speaker 1: Or straight down? I don't know, but I think the
Speaker 1: answer would probably um make you happy, because I think
Speaker 1: that a lot of anthropologists imagine that humans have been
Speaker 1: intelligent for tens of thousands of years, and the major
Speaker 1: evidence of that is basically cartoons. Oh yeah, that's I
Speaker 1: always say, that's a sure sign of intelligence to draw them,
Speaker 1: to be able to draw them, or the sign of
Speaker 1: the society is about to crumble, that's right, and good
Speaker 1: extinct like those ancient civilizations. No, but it's cave paintings, right,
Speaker 1: I mean we can see which are basically cartoons like
Speaker 1: people doing symbolic thinking and describing dogs and buffalo and
Speaker 1: all sorts of things on the walls of caves describing them.
Speaker 1: I think that's the first sign of intelligence. So probably
Speaker 1: around then people started to have thoughts about, you know,
Speaker 1: their situation and how it works and what's the bigger
Speaker 1: what's the bigger situation that their life is in, and
Speaker 1: so I think that's what led them to ask this question.
Speaker 1: So yeah, that's kind of the question is, uh, you know,
Speaker 1: what did humans think about when they asked themselves? What
Speaker 1: happens if I keep going in one direction. And so
Speaker 1: today on the program, we'll be taggling the question is
Speaker 1: the Earth round? That's right? What shape is this crazy
Speaker 1: rock that we're living on? And you know, you can
Speaker 1: look at a lot of things that people describe early on,
Speaker 1: you know, drawings from hundreds or thousands of years ago,
Speaker 1: people trying to draw maps and what the Earth looked like,
Speaker 1: and there's some pretty crazy ideas out there. But if
Speaker 1: you just sort of look around you, or if you're
Speaker 1: just like born in the world and you look around,
Speaker 1: the world looks pretty flat, right, Like, as far as
Speaker 1: you can see, the ground is pretty flat. You think
Speaker 1: that we're sort of on a on a flat surface, right,
Speaker 1: because you your immediate surface around you is flat, and
Speaker 1: kind of you look out a little bit further, it's
Speaker 1: still flat. Yeah, And it seems simple, right, And if
Speaker 1: you're the goal is to understand around you, well, what's
Speaker 1: around you, then the first thing you're gonna do is
Speaker 1: think of the simplest thing. And the world looks kind
Speaker 1: of flat, and you can't see that far away, and
Speaker 1: you know, many surfaces, if you're only looking a small
Speaker 1: portion of them, look flat. I mean, the Earth could
Speaker 1: be all sorts of crazy shapes, and if you only
Speaker 1: look in your neighborhood, it might look flat in the vicinity. Yeah. So,
Speaker 1: and I imagine most of our listeners, um probably think
Speaker 1: or know that the Earth is not flat. But we're
Speaker 1: wondering if people actually know the real answer to the question,
Speaker 1: is the Earth round? Yeah? Or what is the shape
Speaker 1: of the Earth? That's a different Russian What shape is
Speaker 1: it in? That's right? What shape it is it? Politically
Speaker 1: fitness wise, I think we should not be judgmental the Earth.
Speaker 1: I think we should be Earth positive, you know, I think, um,
Speaker 1: this is the one only one we have. And he
Speaker 1: gets depressed and you know, decides to end itself and
Speaker 1: plumbing into the sun. You'll be sorry. That's right, the
Speaker 1: Earth is round and proud? That's right? Exactly. Who wants
Speaker 1: to be on a slender planet anyway? You know? All right? So,
Speaker 1: as usual, Dad, we were wondering what people how people
Speaker 1: out there in the street would answer this question. And
Speaker 1: so Daniel went out there into the street and accosted
Speaker 1: innocent bystanders and asked them a very basic question. That's right.
Speaker 1: And not only did I ask them if they believe
Speaker 1: the Earth was round, but I asked them how they knew,
Speaker 1: which I thought. Let's some of the more fascinating answers. Well,
Speaker 1: let's see what people had to say. Do you believe
Speaker 1: the Earth is round? Yes? Why what evidence do you
Speaker 1: have that the Earth is round? I think it is
Speaker 1: best answered by astronomy is like, of the Earth is round,
Speaker 1: we go. If the Earth is not round, you go.
Speaker 1: You start from a point and you keep going and
Speaker 1: you learn reach to this to your first place. Do
Speaker 1: you agree with me? Says one reason? And there are
Speaker 1: I'm pretty sure there are like lots of proofs about it. Yes.
Speaker 1: Why whateverence do you have the Earth is round? Because
Speaker 1: the idea that satellites are free fall and that they
Speaker 1: free fall around the Earth. So if you throw a ball,
Speaker 1: it goes, it has a curve, and so that kind
Speaker 1: of goes ahead improves that like we're falling innocence, and
Speaker 1: so that can go ahead and explain how satellites can
Speaker 1: fall around the Earth constantly cool orbits. Okay, good answers around, Yes,
Speaker 1: why what everything is do you found? Well, based on
Speaker 1: what everyone else has said, I don't know, there's some evidence,
Speaker 1: but I do believe the Earth is around. Do you
Speaker 1: believe that the Earth is round. What evidence do you
Speaker 1: have inund airplanes? I don't know, pictures of like from
Speaker 1: the I like that, all right, pictures from space other
Speaker 1: other astronomical objects are also around, so good point other
Speaker 1: points around. I do believe there is around. Why is that?
Speaker 1: Whatever you want? I believe this is around because just
Speaker 1: what I've learned in my education growing up middle school
Speaker 1: to high school to college, it's just what I'm familiar with.
Speaker 1: So yes, why whatever pictures NASA? Al right, pretty no
Speaker 1: flat earther is you couldn't find any flat earthers out
Speaker 1: there in Irvine. That's right, good job you see, irline.
Speaker 1: I was really relieved to not run into any flat earthers.
Speaker 1: I mean I was a tiny bit curious, like, what
Speaker 1: would I do if I met a flat earther, Would
Speaker 1: I like engage them in debate on the spot and
Speaker 1: be able to persuade them. Anybody who believes the Earth
Speaker 1: is flat is probably not really open to actual scientific
Speaker 1: dialogue on the subject um. But I was also sort
Speaker 1: of relieved that, like in this educational community, at least
Speaker 1: we've succeeded at that level that everybody understands the basics
Speaker 1: of the world around them. I think the flat earthers
Speaker 1: only exist on the Internet. Sometimes I wonder if the
Speaker 1: flat earthers are all just trolls, you know, if they're
Speaker 1: just being ridiculous to make everybody mad because they get
Speaker 1: their kicks by pissing people off. But I did some research,
Speaker 1: and there's a pretty hardcore group of people out there
Speaker 1: that really, honestly, sincerely believe the Earth is flat. So
Speaker 1: you got pretty much everyone said yes, uh, and they
Speaker 1: all had all pretty good reasons for believing that the
Speaker 1: Earth is around. Yeah, I'll be great. Some of the
Speaker 1: reasons as excellent, and some of the reasons is a
Speaker 1: little weak, like the weaker ones are like, well, everybody
Speaker 1: says so, you know, and that's okay. Like you, you know,
Speaker 1: you should be a skeptical person. You should try to
Speaker 1: think about these things for yourself. On the other hand,
Speaker 1: like if there's something that everybody is believing, probably it's true.
Speaker 1: I mean, there's probably a good reason why, you know,
Speaker 1: scientists and experts and everybody are saying X, y Z
Speaker 1: is true. So while you should be skeptical, you shouldn't
Speaker 1: just toss out everything that experts are saying just because
Speaker 1: you can't prove it yourself. Well, it gets a little
Speaker 1: bit philosophical, because I mean, it's impossible to know everything
Speaker 1: and to be aware of all the evidence for every
Speaker 1: single thing out there in the world, and so at
Speaker 1: some point you do sort of have to be like,
Speaker 1: all right, most scientists believe this. I guess it's probably true.
Speaker 1: That's right. Yes, sometimes you have to talk to an expert.
Speaker 1: And you know, what's the point of talking to experts
Speaker 1: if you're not going to believe what they say? Right?
Speaker 1: Like you ask me physics questions. You don't go off
Speaker 1: and double check every single thing I say? Or do
Speaker 1: you a triple check it? Daniel? Does that mean you
Speaker 1: have to other physicists on the line who are like
Speaker 1: giving the thumbs up of the thumbs down in your
Speaker 1: secret Daniels in my pocket? Man, I'd like some secret
Speaker 1: Daniels in my pocket. Do some of that work for me?
Speaker 1: That'd be awesome. I have a Daniel Grayson and a
Speaker 1: Daniel and defeat green Sun, different shades of Daniel, all
Speaker 1: the colors of Daniel, different fifty shades of Daniel. You
Speaker 1: know there's a fascilating book. I don't know what that
Speaker 1: book is about. I have to be the fan fiction
Speaker 1: version of this podcast, they're not safe for persion. Um.
Speaker 1: The other answer is that I really liked were the
Speaker 1: one people who have their own reasons, you know, who
Speaker 1: had thought about it. They're like, well, that's impossible, and
Speaker 1: here's why they could actually make an argument, you know, like, um,
Speaker 1: everything else out there is round, or we know that
Speaker 1: things are in orbit, right, these are good reasons, um.
Speaker 1: Or you know, people who don't think that the government
Speaker 1: is lying to them about everything. They believe the pictures.
Speaker 1: They believe that, they believe the you know, they believe
Speaker 1: the pictures of other I mean, and I guess you
Speaker 1: can see other planets, right, you can see the moon,
Speaker 1: and with the telescope you can see other planets. Yeah,
Speaker 1: you certainly can. You can see other planets, and they're
Speaker 1: all around. Pretty much everything out there in space above
Speaker 1: a certain size is round, and for good reason, right,
Speaker 1: it's or round dish at least. And the reason is
Speaker 1: just gravity. You know. Any if if you have a
Speaker 1: big enough object, it's gonna have a lot of gravity.
Speaker 1: And then if it's not around, that means that some
Speaker 1: part is further from the center than another part, and
Speaker 1: eventually it's just going to break and roll downhill like
Speaker 1: all mountains on Earth. All mountains on Earth will event
Speaker 1: actually crumble, right due to rain and gravity and other forces. Now,
Speaker 1: a quick word from our sponsor if we're going to
Speaker 1: answer this question, is the Earth round? Let's let's start
Speaker 1: kind of where humans started, right, And so let's start
Speaker 1: first of all with how do we know the Earth
Speaker 1: is not flat? Because that's kind of what your intuition
Speaker 1: would tell you if you never traveled or seen pictures
Speaker 1: from space. Right. Okay, so if you haven't seen pictures
Speaker 1: from space and you're like, you know, natural science kind
Speaker 1: of person a few thousand years ago, how might you
Speaker 1: figure out that the Earth is not flat? Well, the
Speaker 1: you know, the history of it is that people did
Speaker 1: things like they did experiments where they stuck sticks in
Speaker 1: the ground and they look to the shadows. Now, if
Speaker 1: the Earth is flat and the sun is just like
Speaker 1: above us, then every stick is going to have a
Speaker 1: shadow the same length. But if the Earth is round,
Speaker 1: then those shadows is going to be different lengths at
Speaker 1: different places. And so this is like what a Greek
Speaker 1: guy did. He put tall sticks in different towns in Greece,
Speaker 1: and he knew how far away those towns were from
Speaker 1: each other, and he measured the angles of those sticks
Speaker 1: and the length of the shadows, and from that he
Speaker 1: could estimate he could prove that the Earth was round
Speaker 1: and estimated size to pretty good accuracy. What is this
Speaker 1: a like a apocryphal story or for real? Hey? You
Speaker 1: know everything about ancient Greece could be apocryphal, right, The
Speaker 1: whole thing could just be invented as far as as
Speaker 1: far as we know. Um, But you know this is
Speaker 1: um as far as we understand it, This really happened,
Speaker 1: you agree, Greece. Let's talk about whether Greece really happened? Right?
Speaker 1: Is Grease just a conspiracy man? No? But you know,
Speaker 1: the thing about ancient Greece is that we know so
Speaker 1: little of what happened because the Dark Ages and so
Speaker 1: much of what they did was destroyed. And you know,
Speaker 1: we have like a tiny trickle of the vibrant intellectual
Speaker 1: product of that civilization. So we really don't know what
Speaker 1: was going on in ancient Greece. We know a tiny
Speaker 1: little slipper, which is such a tragedy. It breaks my
Speaker 1: heart to think about all those great ideas that were
Speaker 1: just like lost, you know. Um. But anyway, all those
Speaker 1: big wine parties. No, it's just to me. It's it
Speaker 1: breaks my heart when I when I think about you know, um,
Speaker 1: progress that's been made, Things have been figured out, mathematics
Speaker 1: has been developed, and then just just discarded or lost,
Speaker 1: you know, like in huge fires of ancient libraries and
Speaker 1: destructions of civilization. Anyway, we do have some clues about
Speaker 1: what happened in ancient Greece, and there are stories about
Speaker 1: the about folks measuring the size of the Earth using
Speaker 1: basically just two sticks in the ground. Okay, and so
Speaker 1: the ideas that he planted a stick in one town
Speaker 1: and then it's kind of like if you plant the
Speaker 1: stick in California and then you run over to Florida
Speaker 1: and plant another stick there. At any given time of
Speaker 1: the day, the shadows are might be different. Yeah, there
Speaker 1: will be different lengths, right, because those two sticks have
Speaker 1: a different angle with respect to the sun. They're seeing
Speaker 1: the sun at different points in the sky. Yeah, exactly.
Speaker 1: And if the earth, but if the Earth was flat,
Speaker 1: the shadows would be identical. That's right, that's right, Yeah,
Speaker 1: that's that's the point. Yeah. Um No, they wouldn't be
Speaker 1: the same, would they, But there would be the same
Speaker 1: length there might be a different angle, but there would
Speaker 1: be the same length. Pretty sure, Pretty sure. I mean
Speaker 1: it depends on your particular flat earth model, right, But
Speaker 1: on a sphere, it's definitely true that there are different
Speaker 1: lengths and angles and that you can use that to
Speaker 1: measure the size of the sphere. And another key element,
Speaker 1: of course, is knowing that the Sun is really really
Speaker 1: far away, so that the light that comes from it
Speaker 1: is basically always parallel, because otherwise you could try to
Speaker 1: explain the different angles that you get from sticks to
Speaker 1: different places and make it consistent with a flat earth.
Speaker 1: You could try to do that by saying, oh, well,
Speaker 1: maybe the Sun is really close to the Earth and
Speaker 1: that's why we get different angles right over a flat earth.
Speaker 1: But that's silly. We know the Sun is far away.
Speaker 1: If the Sun was that close to the Earth, you
Speaker 1: could see it's apparent size like change as you move
Speaker 1: around the Earth, and we don't see that. So that's
Speaker 1: an important part of the argument. Interesting, but wouldn't that
Speaker 1: require you to have like a walkie talkie between the
Speaker 1: two places, you know, to say, all right, right now,
Speaker 1: measure the length of the shadow. But if you don't
Speaker 1: have that instant communication, how would you like coordinated and
Speaker 1: know that it was measured at the same time. That's
Speaker 1: a good question. I don't know how they managed it.
Speaker 1: Maybe they had walkie talkies in ancient Greece increase, They
Speaker 1: definitely didn't. We don't know anything they could have burned
Speaker 1: with the labrary. I mean that the power of the
Speaker 1: test is greater the further the sticks are apart. But
Speaker 1: I don't know how far apart they have to be
Speaker 1: for you to have a measurable effect. It might not
Speaker 1: have to be very far, you know, so you might
Speaker 1: be able to say, like, all right, we'll both walk
Speaker 1: for an hour and then plant a stick and then
Speaker 1: measure the length, and it might be enough, Oh I see,
Speaker 1: or maybe like a smoke signals or something like if
Speaker 1: it's several miles and you can still do it, yeah,
Speaker 1: smoke signals exactly. Um, you'd be good at inventing physics
Speaker 1: experiments in ancient Greece. Yeah, I definitely want to around. Um.
Speaker 1: But there are also other ways. You don't have to
Speaker 1: do two sticks in the ground, Like, there are other
Speaker 1: ways to figure out that the Earth is round, even
Speaker 1: even without technology. All right, what are those ways? Well,
Speaker 1: you can just look at the stars. Right, travel the
Speaker 1: Earth and look at the stars. You see different stars
Speaker 1: from different parts of the Earth. Right. If the Earth
Speaker 1: is flat, then everybody should be seeing the same sky.
Speaker 1: I mean, you'll be seeing it from a slightly different
Speaker 1: point of view if you're in a different spot on
Speaker 1: the Earth. But some stars are blocked by the earth.
Speaker 1: Right you walk from you walk from North America to
Speaker 1: South America, you're gonna see different stars in the sky. Right,
Speaker 1: the northern stars you can't see them because the Earth's
Speaker 1: curvatures in the way. Oh I see. So if you
Speaker 1: assuming you can remember the sky right, or you can
Speaker 1: draw it for example, Yeah, you heard of that drawing
Speaker 1: only in caves. I only know that kind. And you
Speaker 1: can't see the stars when you're in a cave, so
Speaker 1: you can sort of you chisel along the side of
Speaker 1: you join on the side of the cave. You walk
Speaker 1: to South America, you draw another cave, and they're like, hmmmm,
Speaker 1: I should have brought my cave with me. That's how
Speaker 1: they invented the portable cave, probably otherwise known as the tent. Okay.
Speaker 1: So that's another way you would tell, right, is you
Speaker 1: would uh notice that the stars are different in different
Speaker 1: parts of the Earth, which means that the Earth can't
Speaker 1: be flat. That's right, that's another reason. Another way you
Speaker 1: can tell, again without really much technology, is just seasons.
Speaker 1: Like how do you get seasons on a flat earth? Right?
Speaker 1: I mean different parts of the earth have difference. You
Speaker 1: might say, okay, we can get north, we can get
Speaker 1: winter the sun goes further away, we can get summer
Speaker 1: when the sun gets closer. But we have different seasons
Speaker 1: and different part of the earth. Right, we have summer
Speaker 1: in the northern hemisphere when we have during the southern hemisphere.
Speaker 1: How do you account for that? Well, I mean if
Speaker 1: I if I live thousands of years ago, I mean
Speaker 1: I wouldn't know. I wouldn't know anything, right for all?
Speaker 1: For all I know there are gods and weird you know,
Speaker 1: magical beings that make it winter here, and some are there, yes, absolutely,
Speaker 1: And there is always another explanation that's like ridiculously complicated,
Speaker 1: involves magic and gods are like crazy trajectories that can
Speaker 1: explain all the data. But we prefer the simplest, right,
Speaker 1: If the simplest explanation is that the Earth is a
Speaker 1: body just like all the other ones we see, and
Speaker 1: it looks just like them, and it's also circular. It's
Speaker 1: also basically spherical, and that explains everything we see. And
Speaker 1: so it's like, by far the explanation we prefer to,
Speaker 1: there's some crazy magic aliens out there doing some crazy
Speaker 1: tricks on us, or here on Earth? Are you here
Speaker 1: on Earth? Exactly? Okay? Cool? And then what's the last
Speaker 1: last experiment you as a Greek scientist can do. Well?
Speaker 1: The simplest one is that you can see hints of
Speaker 1: the curvature. I mean you can look at ships, for example,
Speaker 1: coming over the horizon from far away, like what's blocking them? Right? Ships? Um?
Speaker 1: Coming over the horizon, You're seeing them come over the
Speaker 1: curvature of the Earth. Right, that's pretty direct right there. Um.
Speaker 1: And in a similar way, you can see further when
Speaker 1: you get higher up, Like if the Earth was flat,
Speaker 1: then you couldn't see any further by getting any higher up,
Speaker 1: or you can see at a different angle, right, but
Speaker 1: you couldn't see any further. But on a spherical Earth
Speaker 1: or nearly spherical earth, the higher you go, the less
Speaker 1: the Earth's curvature blocks you, the larger your field of view.
Speaker 1: And that's exactly what you experience. You go to a skyscraper.
Speaker 1: At the top of a mountain, you can see much further. Okay,
Speaker 1: so I guess the idea is that is that if
Speaker 1: the Earth was flat and you were standing at the
Speaker 1: beach and you saw a ship go off and away
Speaker 1: from you, it would just get smaller and smaller and
Speaker 1: smaller and smaller and smaller and smaller and smaller. It
Speaker 1: wouldn't ever disappear from view, that's right, and you could
Speaker 1: eventually see it like doc in Japan or something. Right,
Speaker 1: if you had a super duper telescope. Oh, it would
Speaker 1: just look really really really small. But you could technically
Speaker 1: see Japan if the Earth was flat, I mean, Japan
Speaker 1: is close. You'd be limited by basically the air, right,
Speaker 1: the air wiggles makes things fuzzy. But yeah, technically you'd
Speaker 1: be able to see all the way across the ocean.
Speaker 1: If the Earth was flat. Oh wow, that would be cool. Yeah,
Speaker 1: that would be pretty cool, wouldn't it. It would be
Speaker 1: cool was flat, But I guess it'd be nighttime in Japan.
Speaker 1: That would be awesome. Actually, you could like see different
Speaker 1: time zones. Oh, I see, but even if I take
Speaker 1: a telescope and I look out into the ocean with
Speaker 1: a telescope, I would just at some point see nothing
Speaker 1: because my line aside would just go off into space.
Speaker 1: That's right. And if you're on a boat in the
Speaker 1: middle of the ocean, all you can see is water
Speaker 1: because everything else is around the curve of the Earth, right, Okay,
Speaker 1: And then you have one more last um Greek experiment
Speaker 1: you can do right involving sunsets. Yeah. I mean there's
Speaker 1: a long list of reasons, some that we believe the
Speaker 1: Earth is round, but another one is, yeah, sunsets, Like
Speaker 1: how do you explain sunsets on a flat earth? You
Speaker 1: know the models I've seen a flat earth to have, Like,
Speaker 1: I mean, it's kind of ridiculous. But you have this
Speaker 1: flat plane and then you have the Sun which is
Speaker 1: really small compared to the Earth, and it's sort of
Speaker 1: moving around the circular Earth, right for the flat earth
Speaker 1: like a lamb, because like a lamb just going around
Speaker 1: around it. Yeah, and it's like shining like a spotlight,
Speaker 1: like it's directional or something. So you know, I don't
Speaker 1: understand how you get day or night because the Sun
Speaker 1: is a sphere. We can see that it's a sphere, right,
Speaker 1: It's definitely it would shine on the whole surface of
Speaker 1: the Earth all the time. I mean, if you had
Speaker 1: a flat Earth with the sun above it, then you
Speaker 1: would have never had night time unless the sun went
Speaker 1: below the flat Earth, in which case every part of
Speaker 1: the Earth would see sunset at the same time, which
Speaker 1: definitely doesn't happen. Okay. So I think the point is
Speaker 1: that even if you are super skeptical of scientists and
Speaker 1: you don't believe anything anyone ever tells you or believe
Speaker 1: any pictures you see, there are still ways that you
Speaker 1: could be convinced yourself that the Earth is not flat.
Speaker 1: That's right. And people did these things and they figured
Speaker 1: them out, and that's why people believe the Earth is round,
Speaker 1: even well before we had technology. But now that we
Speaker 1: have amazing technology, it's pretty easy to discover that the
Speaker 1: Earth is round. So the because you know, I grew
Speaker 1: up in um in Panama, and for us, you know,
Speaker 1: Christopher Columbus was like a big deal, and so you know,
Speaker 1: as a kid, you just like you always hear like, oh,
Speaker 1: he proved that the Earth was round. But that's um,
Speaker 1: that's a little bit of historical Bologna're right, Yeah, I
Speaker 1: think it was widely spread among anybody who had any education. Uh,
Speaker 1: the belief that the Earth was round was already widely
Speaker 1: spread by then, but I guess he was the first
Speaker 1: or one of the first to really kind of connected physically.
Speaker 1: I mean, I never really understood that argument because Christopher
Speaker 1: Columbus was trying to use the fact that the Earth
Speaker 1: was round to get to India, right, and so he
Speaker 1: thought he got to India. He's like, okay, look, I
Speaker 1: got to India, and therefore the Earth is round. But
Speaker 1: the problem is he didn't get to India, so he
Speaker 1: didn't prove anything, right. He just proved that if you
Speaker 1: get in the in the boat and sail, you get
Speaker 1: to some more land. He didn't really prove anything at all.
Speaker 1: I mean, Christopher Columbus, Like, there's so much trouble with
Speaker 1: Christopher Columbus, you know, on top of genocide and miss
Speaker 1: miss naming Americans as Indians and all that sort of stuff,
Speaker 1: but he didn't he didn't really prove the Earth is
Speaker 1: round at all. Okay, but I guess, um, I guess
Speaker 1: we won't get into the politics of it. It's pretty dark.
Speaker 1: But yeah, so alright, so then, um, that's how we
Speaker 1: know that Earth is not flat. And so let's let's
Speaker 1: get into whether the Earth is actually round or not.
Speaker 1: But first let's take a quick break. All right, So
Speaker 1: we talked about how if you were a Greek scientist
Speaker 1: back in the day, you might be able to figure
Speaker 1: out that the Earth is not flat. But yeah, how
Speaker 1: about today, like you know, we we as citizens have
Speaker 1: every day sittings, have access to a little bit more technology. Um,
Speaker 1: so how would how could a scientists today without if
Speaker 1: they didn't believe pictures or other scientists, how could we
Speaker 1: um find out? How can we be be scientists and
Speaker 1: conclude that the Earth is not flat? You mean without
Speaker 1: being Elon Musk and having our own spaceship company and
Speaker 1: going into space ourselves with that being billionaires, let's say
Speaker 1: you just have like, you know, a hundred dollars ten
Speaker 1: dollars in your pocket. Because the billionaire the billionaire demographic
Speaker 1: of our listeners is probably pretty small, right, but if
Speaker 1: we have one, hey, give us a call. Please send
Speaker 1: us an email. All the billionaires out there, please send
Speaker 1: us an email. We want to record an episode from
Speaker 1: space that's right, featuring you. Well, first I want to
Speaker 1: comment on like should you disbelieve other scientists? And again
Speaker 1: it's healthy to be skeptical. There are times when people
Speaker 1: everybody's wrong about something, But let's remember that everybody out
Speaker 1: there doing science is trying to be right, you know,
Speaker 1: they want to figure it out. They're not out there
Speaker 1: trying to convince people of things that are not true.
Speaker 1: Like NASA is not lying to people. There's no crazy agenda,
Speaker 1: and it's impossible for that to even be Um, it's
Speaker 1: not practical for that to happen because NASA is filled
Speaker 1: with a bunch of scientists who all want to figure
Speaker 1: out the right answer and share it. So if there
Speaker 1: was some absurd conspiracy to like lie to the public
Speaker 1: for ridiculous reasons about the shape of the Earth, somebody
Speaker 1: out there would just prove it. Somebody out there and
Speaker 1: be like ha ha, look I'm um, I have proof,
Speaker 1: and somebody would would get the credit for that. So
Speaker 1: science is filled with people who want the truth and
Speaker 1: want to share the truth, and sometimes they make honest mistakes.
Speaker 1: But it's it's impossible to imagine a widespread scientific conspiracy.
Speaker 1: I think also, even if you don't believe in the
Speaker 1: altruism of scientists, I always like to think and sit
Speaker 1: tell people that you know, like if you ever meet
Speaker 1: a scientist, each one of them, and maybe you can
Speaker 1: prove me wrong. But like I think, each one each
Speaker 1: scientists out there would love nothing more than to be
Speaker 1: the guy that disproves everybody else. Yeah, exactly, even from
Speaker 1: a cynical point of view, right, they all want the
Speaker 1: glory that I would love to reveal that all of
Speaker 1: science has misunderstood something. I mean, I think I've said
Speaker 1: that on this podcast before. That's my personal scientific fantasies
Speaker 1: to discover something which forces us to rethink foundational ideas. Right,
Speaker 1: that's fantastic. Everybody would love to be in that position.
Speaker 1: And so to prove that the Earth is a different
Speaker 1: shape than everybody thought, Wow, that would be fantastic. So, yeah,
Speaker 1: you're right, from a purely selfish point of view, if
Speaker 1: scientists say something and you know that they're all trying
Speaker 1: to prove each other wrong, you know the fact that
Speaker 1: they agree is like extra extra validity, exactly exactly. But
Speaker 1: imagine that, you know you want to check her for yourself.
Speaker 1: You want to be the scientist to disprove everybody. How
Speaker 1: could you do that? That was your question, And these
Speaker 1: days it's actually not that hard because of the ubiquity
Speaker 1: of basically high resolution cameras. Um, all you need to
Speaker 1: do is take a picture from high enough that you
Speaker 1: can see the curvature of the Earth. And to get
Speaker 1: high enough to like really see the curvature in an
Speaker 1: indisputable way, you need to be like thirty five forty
Speaker 1: forty feet up above the ground to see the curvature
Speaker 1: of the Earth. I guess, you know, um, it's not
Speaker 1: immediately clear what that means. So I guess if you
Speaker 1: go out really really far, like to the moon, you
Speaker 1: would definitely see the Earth is round, right, that's right,
Speaker 1: and but down here it looks flat. And so as
Speaker 1: you keep going up and out, you're going to see
Speaker 1: kind of more more of the rounded shape of the Earth. Exactly. So,
Speaker 1: as you imagine you're floating up from the Earth, right
Speaker 1: first it seems flat, and then you get higher and
Speaker 1: higher up, you're, like you know, at airplane levels, it
Speaker 1: still seems mostly flat. But as you zoom out you
Speaker 1: see it more as a planet, unless it's just a surface, right,
Speaker 1: You're zooming away from it to get more perspective on
Speaker 1: the overall shape of it, and then you can start
Speaker 1: to see the overall shape. You can see this curvature,
Speaker 1: and you know, above forty feet or so, it becomes
Speaker 1: pretty clear and you might be thinking, well, how do
Speaker 1: I get about forty feet? And the only way to
Speaker 1: do that through an airplane and those windows are weird
Speaker 1: and have curves and whatever, how do I really believe that? Well,
Speaker 1: all you need to do is send your phone up there,
Speaker 1: and folks have done this. You can. You can just
Speaker 1: build a weather balloon, which is basically just a big
Speaker 1: bag of helium or hydrogen, and attach a phone to
Speaker 1: it and it'll go up really really high, you know,
Speaker 1: eighty thou ft a hundred thousand feet basically up to
Speaker 1: near space. And high schoolers have done this. You know,
Speaker 1: you can google for pictures of it. Wait, what what
Speaker 1: do you do? Though? You do? You start like a
Speaker 1: FaceTime conversation and then send it up. There's no service
Speaker 1: up there, but you you know, you start recording and
Speaker 1: you send it up. And then the trick of course,
Speaker 1: is recovering it. Right where does it come down? So
Speaker 1: you just have it like take pictures. Every couple of
Speaker 1: seconds it goes up, the balloon, balloon pops, it falls down,
Speaker 1: and then you recover it and you get the pictures. Yeah, exactly.
Speaker 1: You have a little parachute, right, so it doesn't just
Speaker 1: plummet to earth and burn up and re entry and smash.
Speaker 1: And then you get the pictures and they're pretty fantastic
Speaker 1: pictures and it's very clear, and those pictures the curvature
Speaker 1: of the Earth, and they're gorgeous too. I mean, they're
Speaker 1: beautiful pictures. It wouldn't be like an effect of the
Speaker 1: fish eyelands or anything. No, absolutely not. I mean you
Speaker 1: can see it increasing with altitude, right, So it's not
Speaker 1: an artifact. So if you have an iPhone to spare
Speaker 1: and a weather balloon, you could you could discover that
Speaker 1: the Earth is round or or are they right? That's
Speaker 1: kind of the question that we post at the beginning, right,
Speaker 1: is the Earth actually round or not? That's right? And
Speaker 1: so we're pretty sure that is not flat. And if
Speaker 1: you look at pictures some space, you're like, okay, the
Speaker 1: Earth is round, right, it looks pretty round, But let's
Speaker 1: get precise, like do we really mean the Earth is
Speaker 1: like round? Is it a perfect sphere? Well, the key
Speaker 1: is that the Earth is spinning, right, and spinning things
Speaker 1: have extra complications, like if the Earth was not spinning
Speaker 1: it would, it would be perfectly round. You think, if
Speaker 1: the Earth is not spinning, would be much closer to
Speaker 1: perfectly round. Now, perfectly perfectly round is impossible. I mean,
Speaker 1: even if you like sanded the Earth down microscopically, there's
Speaker 1: no way to get all the atoms exactly the same
Speaker 1: distance from the center of the Earth, you know, and
Speaker 1: microscopic level level, perfectly round is impossible, even perfectly around
Speaker 1: it like the you know, the one mile level is
Speaker 1: pretty tough because you've got mountains, right, mountains and valleys
Speaker 1: and all sorts of stuff, um, and eventually those will
Speaker 1: you know, roll down into rubble. But then thanks to
Speaker 1: play technoics, you'll get new mountains. So the one two
Speaker 1: mile level, you know, the level even of like Mount Everest,
Speaker 1: it's pretty hard to have it be perfectly flat. But
Speaker 1: there's an even bigger effect, which is because the Earth
Speaker 1: is spinning, and so it's it's not perfectly symmetric anymore. Right,
Speaker 1: the Earth is round, it seems you might think like
Speaker 1: every direction should be the same, but it's not, because
Speaker 1: the Earth is spinning on a specific axis, and that
Speaker 1: spinning has this effect of pushing things away from that axis.
Speaker 1: The north, south axis. It's like if you're on a
Speaker 1: merry go round and somebody spins it, you feel this
Speaker 1: this effect that's trying to throw you off the merry
Speaker 1: go round, right, unless you're holding on. And so the
Speaker 1: same way if you if you spin up, if you
Speaker 1: take a planet that's not spinning and you spin it,
Speaker 1: it's gonna make it a little bit flatter and a
Speaker 1: little bit of sort of blobbier. Right, It's gonna make
Speaker 1: things further away from the center at the equator and
Speaker 1: a little closer in at the polls. Is it that
Speaker 1: it's pushing the stuff out in the on the equator
Speaker 1: outwards or is it that maybe the stuff on the
Speaker 1: equator doesn't feel as much gravity as the stuff in
Speaker 1: the north and South pole. No, it's an effect of
Speaker 1: the rotation. It's like if you take um, you know, pizza,
Speaker 1: you're spinning to take a pizza and you spin it, right,
Speaker 1: it gets bigger. Why does it get bigger? Right? Because
Speaker 1: it's the spinning. The spinning has this effective forces centrifugal
Speaker 1: force um that pushes things out and it's an artifact
Speaker 1: of the spinning. So like if if I'm feeling a
Speaker 1: little bit round and padded in my middle section here.
Speaker 1: It could be because I've been spinning too much. There
Speaker 1: are other explanations, but the has really simpler explanations. Too
Speaker 1: many banana cream pies, don't know. Yeah, but if you
Speaker 1: take something, you know, take like a ball of dough,
Speaker 1: and you spin it, then it will flatten, right, it
Speaker 1: will flatten, and it'll get um wider and in the
Speaker 1: middle and and uh and shorter on the top, oh,
Speaker 1: get shorter. And so that's what's happened to the Earth.
Speaker 1: That's what happened to Earth. Yeah, but you know, don't
Speaker 1: be alarmed as it formed or after it formed, do
Speaker 1: you know what I mean? Or like it's always been oblong,
Speaker 1: it's always been not round. That's a great question. It's
Speaker 1: definitely true as long as the Earth has been spinning.
Speaker 1: And I'm pretty sure the Earth has been spinning since
Speaker 1: it was formed, because it's been angular momentum um. But
Speaker 1: that must have changed, like for example, on the planet Uranus. Right,
Speaker 1: Urinus was hit by something really big that knocked it
Speaker 1: off at spinning in a different direction. That probably changed
Speaker 1: the shape of Urinus also, so that's a cool question. Yeah, yes,
Speaker 1: So if you change the spin of a planet, it
Speaker 1: will change its shape. And aren't their theories that say
Speaker 1: that our moon. We had a whole podcast about it,
Speaker 1: by the way, you guys can look at it, look
Speaker 1: for it in the arch in the archive. But it
Speaker 1: isn't there a theory that maybe we were hit by
Speaker 1: a giant rock and that's how the moon form, and
Speaker 1: so maybe our ax has also changed. Yeah, it could be.
Speaker 1: It could be we were spending a faster or slower
Speaker 1: before that massive collision and that would change the shape
Speaker 1: of the Earth. But you know, taking a moon size
Speaker 1: chunk also changes the shape of the Earth. So that
Speaker 1: was a big event in terms of shape of the Earth. Um.
Speaker 1: But people might be wondering out there, like how big
Speaker 1: an effect is this is, like, you know, because if
Speaker 1: you look at the pictures from the from space, the
Speaker 1: Earth looks pretty round. I mean maybe people haven't done
Speaker 1: like precise measurements of those photographs, but it does look
Speaker 1: pretty round, and it is pretty round. The answer is
Speaker 1: that the at the equator, the distance to the center
Speaker 1: is about thirteen miles more than it is at the polls.
Speaker 1: So the Earth is wider than it is taller by
Speaker 1: thirteen miles by thirteen miles and on one hand, that's
Speaker 1: a big difference in each direction. Each direction. Yeah, from radius.
Speaker 1: On one hand, that's a big difference because like some
Speaker 1: of the biggest features on Earth, like Mount Everest, are
Speaker 1: only a few miles high, so this is like two
Speaker 1: or three times bigger than that. Right. On the other hand,
Speaker 1: it's pretty tiny because you know, the radius of the
Speaker 1: Earth is thousands of miles, so it's a really pretty
Speaker 1: small effect. Like if you were holding the Earth in
Speaker 1: your hand, could you tell this difference if you like
Speaker 1: roll the Earth against a um along a smooth surface,
Speaker 1: when you notice it not rolling perfectly smoothly. I'm not sure.
Speaker 1: I think we would, we who live on the surface
Speaker 1: of Earth would notice it for sure. I'm trying to
Speaker 1: be that cosmic alien that's playing games with us, right,
Speaker 1: it's playing tricks. Imagine the galactus, your galactus just there.
Speaker 1: Um yeah, thanks. From from that point of view, I
Speaker 1: think it'd be pretty hard to tell. You know, I
Speaker 1: don't know. For example, like a very high quality poolball,
Speaker 1: you know, like billiard ball, Um, what's the level of
Speaker 1: sphericity of that and how does it compare to the Earth.
Speaker 1: That's a good question. Like a professional great billiard ball ball.
Speaker 1: Is it actually also even a sphere? Yeah, I don't
Speaker 1: even know. It might be more spherical mirath, or it
Speaker 1: might be spherical within the same tolerance, right, because thirteen
Speaker 1: miles is a small fraction of the radius of the Earth.
Speaker 1: And you're talking about kind of like the average distance
Speaker 1: to the center of the Earth, right, because there are
Speaker 1: sort of dips and valleys and oceans and stuff, but
Speaker 1: like the average that's right. Yeah, Well, I guess the
Speaker 1: question is why isn't it more oblong? You know what
Speaker 1: I mean? Like the Earth is speling pretty fast at
Speaker 1: least once a day that I know of, and that's
Speaker 1: a lot of earth to move around. Why is it
Speaker 1: it more like opal shaped? Yeah? Well that depends on
Speaker 1: sort of the internal strength of the earth. Right. If
Speaker 1: the Earth was made out of like, I don't know,
Speaker 1: cotton candy or something, and you spun it this fast,
Speaker 1: then probably a bunch of the cotton candy would get
Speaker 1: flung out in the space. Um, but it holds itself together, right,
Speaker 1: depends on the strength of the material. Like if the
Speaker 1: Earth was made out of pizza dough, we would be
Speaker 1: much flatter, that's right. And also there's gravity, right, Gravity
Speaker 1: does like to keep things together. So there's a bunch
Speaker 1: of things at play there. But you have the Earth
Speaker 1: is made out of pizza dough, it would have a
Speaker 1: different shape than it does today. Let's do that experience.
Speaker 1: Let's build a planet sized blob of pizza, just just
Speaker 1: to find out that's right. Let's make a piece of
Speaker 1: shop for the galactuses of the universe. Any listening billionaires,
Speaker 1: that's where you should send your funds, and then also
Speaker 1: send us into space to go eat some of this pizza.
Speaker 1: That's right. That's gonna take a lot of sauce. Al right. Well,
Speaker 1: so that that's the answer to the question. Is the
Speaker 1: Earth round? The answer is no, right, it's around dead right,
Speaker 1: round dish, but almost sort around. It's rounded, more rounded
Speaker 1: in the middle of the Earth is definitely not flat,
Speaker 1: but I mean it's definitely not flat, that's right, Like
Speaker 1: many of us, the Earth is definitely not flat. Definitely
Speaker 1: not flat. So not flat, oh my god, definitely not flat. Um,
Speaker 1: it's almost perfectly spherical. And that well. The other way
Speaker 1: you can just test that the Earth is round is
Speaker 1: just go off in one direction, right and just get
Speaker 1: on a plane and keep going. That's right, you know.
Speaker 1: The flat earthers have an answer to that. They say, well,
Speaker 1: the Earth is flat, um, and if you move in
Speaker 1: a circle, you're actually moving in a circle on that surface,
Speaker 1: which is crazy. It doesn't make any sense because if
Speaker 1: I see, there's an answer for you, well, but then
Speaker 1: you know, no, those answers make sense. Like if the
Speaker 1: Earth was flat, they put the north pole at the
Speaker 1: center and the South pole is like this wall of
Speaker 1: ice around the circular flat Earth. But if that were true,
Speaker 1: then that would really stretch out distances between stuff in
Speaker 1: the southern hemisphere because the sun the hemisphere would become huge.
Speaker 1: In the northern hemisphere would be compressed, and so you
Speaker 1: would definitely notice, like if you try to sail on
Speaker 1: a ship from you know, Chile to China, you would
Speaker 1: notice that it took you way longer than it should.
Speaker 1: Shipping captains and airplane pilots would definitely notice if the
Speaker 1: Earth was flat, all right, Well, and there's then then
Speaker 1: there's a whole totally different question, which is is space flat? Right?
Speaker 1: Like we could be a rounded Earth on a flat
Speaker 1: on flat space, right, or a rounded Earth on a
Speaker 1: round space. That's right, And I'm definitely a flat spacer.
Speaker 1: Were a round earther put a flat space. That's right,
Speaker 1: No space seems to be flat, and that's really weird, right,
Speaker 1: we don't understand why space is flat. For those of
Speaker 1: you who don't even know what that means, check out
Speaker 1: our podcast on the shape and size of space. Space
Speaker 1: is a weird, crazy thing and do all sorts of
Speaker 1: stuff you never imagined, including being curved or not being curved.
Speaker 1: And you might be able to send your iPhone out
Speaker 1: into the universe to find out that's right, leave the
Speaker 1: round Earth and go into flat space and learn some things. Um.
Speaker 1: But this is what I love about these questions, you know,
Speaker 1: they tell us so much about where we are in
Speaker 1: the world. And to discover that the Earth is round
Speaker 1: and it looks just like all those other planets must
Speaker 1: have been a huge shock to the people who discovered that, right,
Speaker 1: to understand something so deep about this, this situation we
Speaker 1: find ourselves in. Those are the wonderful moments in science,
Speaker 1: right when you get these flashes of insight and reveal
Speaker 1: something about the context of the human experience. Yeah, or
Speaker 1: like challenges everyday conceptions or ideas that you might have
Speaker 1: right exactly. The first guid figure out the Earth was round.
Speaker 1: Probably everybody scoffed at him and thought, oh, he's crazy.
Speaker 1: He's one of those round earthers. Right. The Internet, the
Speaker 1: Greek Internet, the Marble net, I think that a marble
Speaker 1: net back in Asian Greece. Yeah, they're all just talking
Speaker 1: under walkie talkies, posting trolling comments. It's too bad we lost.
Speaker 1: I mean, the Greeks developed the walkie talkie technology and
Speaker 1: then we lost in the Dark Ages. We had to
Speaker 1: reinvent it. Oh my gosh. Yeah, man, we had to
Speaker 1: reinvent the walkie talkie. Yeah, exactly. So much of human
Speaker 1: civilization was lost. Um no, but I think it's it's
Speaker 1: wonderful when we have those moments when we understand something
Speaker 1: deep about the human experience. All right, well, if you
Speaker 1: are a flat earther, um, we're sorry that this podcast
Speaker 1: disappointed you, And if you were around Earth, we're also sorry.
Speaker 1: Sorry that you're disappointed that the Earth is not round.
Speaker 1: But if you're a pizza ball earther, then congratulations, you're right,
Speaker 1: the Earth is a pizza ball. And if you were
Speaker 1: a flat there and you listen to this podcast and
Speaker 1: you were convinced link, congratulations for having an open mind.
Speaker 1: We'll hope you guys enjoyed that. Thank you for listening,
Speaker 1: See you next time. If you still have a question
Speaker 1: after listening to all these explanations, please drop us a line.
Speaker 1: We'd love to hear from you. You can find us
Speaker 1: at Facebook, Twitter, and Instagram at Daniel and Jorge That's
Speaker 1: one Word, or email us at Feedback at Daniel and
Speaker 1: Jorge dot com. Thanks for listening, and remember that Daniel
Speaker 1: and Jorge Explain the Universe is a production of I
Speaker 1: Heart Radio. For more podcast from my Heart Radio, visit
Speaker 1: the i heart Radio app, Apple Podcasts, or wherever you
Speaker 1: listen to your favorite shows.