Why The Sun is Bigger Than You Think

Here is a brief summary of the key points from the transcript: - The diameter of Earth is about 8,000 miles. Using the circumference formula, the circumference of Earth is around 25,000 miles. - The sun's diameter is around 864,000 miles, making it about 100 times wider than Earth. - The sun is not a perfect sphere - it is an oblate spheroid, slightly flattened at the poles. Its diameter differs slightly between the equator and poles. - The sun's visible "edge" is called the photosphere, the layer where light can escape directly. But the sun has outer layers like the corona beyond this. - The sun's diameter depends on what wavelength of light you use - it appears different in X-rays compared to visible light. - If the sun were hollow, about a million Earths could fit inside it. - The transcript emphasizes that the sun is enormously larger than Earth, contrary to ancient beliefs that put Earth at the center of the solar system.

Speaker A: Chuck out another explainer.

Speaker B: Awesome.

Speaker A: The diameter of the sun.

Speaker B: Okay, this sounds boring.

Speaker A: The diameter of the earth is about 8000 miles. And. Thank you.

Speaker B: And that's it. Did not know that. So I'm already good.

Speaker A: It's about 8000 miles.

Speaker B: 8000 miles.

Speaker A: Okay. And from that, you can know their circumference, if you remembered PI. Okay. The circumference equals PI times the diameter.

Speaker B: Okay.

Speaker A: And how much is PI?

Speaker B: 3.14 or something.

Speaker A: Exactly. So a little over three. So you multiply 8000 miles times three and a little bit, you get at least 24,000 miles around and some change. It's about 25,000 miles circumference. Right. Fine. And we did, I think we did on a separate explainer that the diameter of Earth, pole to pole, is less than the diameter of Earth in the equator. We talked about that. Earth is slightly flat spheroid. That's what an oblate spheroid is. That's flattened top to bottom.

Speaker B: Okay. Yeah.

Speaker A: The sun is also shorter top to bottom than across its equator.

Speaker B: Interesting.

Speaker A: Not by much, but it's measurable. Okay, so when someone asks what's the diameter of the sun, what answer are you gonna give them? Are you gonna give them pole to pole? You gonna give them across the diameter? You gonna take the average of those two? I just want you to appreciate that when you look up a numerical answer to a question, right. Depending on what it's answering, the question might not have an actual answer. We just have to sort of set the rule. The diameters are gonna be across the equator for everybody.

Speaker B: What's the diameter?

Speaker A: Oh, that's, you know, you need the high frequency.

Speaker B: Right. You need, you know, that lets them know that it's not exact.

Speaker A: Okay?

Speaker B: Yeah.

Speaker A: So now you say, all right, let's say we do equator. Now you look up at the sun with filters. Then you see this sharp edge. Right? The edge of the sun has an edge. Right. Okay, but wait.

Speaker B: Uh oh.

Speaker A: The sun is made of what?

Speaker B: Plasma.

Speaker A: Plasma. It's gas, basically. Okay. Plasma gas. When was the last time you saw gas have a sharp edge to it?

Speaker B: That'd be my uncle Darryl.

Speaker A: When that smell moved across the room, it had sharp edge, sharp edge. You either in it or out.

Speaker B: Good man. You know, it's time to go.

Speaker A: Yeah. The spherical ball that is the sun oblate spheroid, that is the sun. We speak of an edge, but that's an edge made of gas.

Speaker B: Right.

Speaker A: Okay.

Speaker B: How do you even have that?

Speaker A: That's my point. It's like Earth's atmosphere, right? Where's the edge of Earth's atmosphere? No, there is no edge. It's gas that becomes sort of thinner.

Speaker B: Thinner and thinner. You know, you reached it when you're like.

Speaker A: So when we see the sharp edge of the sun, in practice, we were referring to what's called the photosphere. Oh. The photosphere is a layer of the sun's atmosphere, which is the last point of contact with the photon trying to get out of the sun. Ooh.

Speaker B: Okay.

Speaker A: Okay. And now the photon can move at the speed of light in a straight line. Until that point, it was bouncing back and forth among other molecules and other atoms and other particles. By the way, had that photon been moving in straight lines, you'd be able to see deep inside the sun. Oh, that's what light moving in straight lines means, right?

Speaker B: Yes.

Speaker A: Why is a window transparent to you? Because the light moved in a straight line through the window.

Speaker B: Right.

Speaker A: But then I smoked the window. You know, what do you do when you frost it? I frost the window.

Speaker B: Right.

Speaker A: And now the light, I can't get through. I gotta jiggle a little bit. I'll still come through, but I'm not in a straight line.

Speaker B: Right.

Speaker A: You cannot see through the window.

Speaker B: No. Yeah. The window's lit up, but you can't see what's on the other side.

Speaker A: The light's coming through, but it's not a straight line.

Speaker B: It's not a straight line.

Speaker A: Okay. All right. So the photon gets to this place, an edge where it can now escape for free. There's not enough above it to keep bouncing around.

Speaker B: Right.

Speaker A: That edge is the photosphere, and that is our definition of the edge of the sun. That's only using visible light.

Speaker B: Oh, God.

Speaker A: Okay.

Speaker B: I knew there had to be a twist to this.

Speaker A: So we are visible light biased.

Speaker B: Right.

Speaker A: I don't mind that. But don't declare that this be the diameter of the sun. If the diameter of the sun is simply what your own damn eyeball can see.

Speaker B: Right. Oh, my.

Speaker A: Right. So if you look at the sun in x rays, okay, it has a different diameter.

Speaker B: Really?

Speaker A: X ray photons are coming from a different place. Okay. A different surface. So we are biased. And I think we need the occasional reminder that we are eyeball biased. Diameter of the sun is where the visible light comes from, and specifically yellow light right in the middle of the spectrum. Red, orange, yellow, green, blue, violet. Right in the middle. Let me keep going.

Speaker B: Go ahead.

Speaker A: There's a layer of sun's atmosphere on top of that.

Speaker B: On top of this photosphere.

Speaker A: Yes. You know what that's called? Mm mm. The corona.

Speaker B: Oh, yeah. Okay.

Speaker A: That's part of the sun.

Speaker B: That's part of the sun.

Speaker A: Why is your diameter not including that?

Speaker B: Right.

Speaker A: That's part of the sun. The corona, depending on where the sun is in its cycle, can be really big or really small. So that changes on an eleven year cycle. But wait. The sun has a magnetic field that extends beyond the corona, right? That's called the magnetosphere. Shouldn't that be part of the diameter of the sun?

Speaker B: It's part of it.

Speaker A: Part of the son?

Speaker B: It's part of it.

Speaker A: All right. All I'm saying is, if you seek the truth, my son be aware that the truth has many faces. One face may deceive you into thinking that it is the face of the answer to that question. Let you not be blinded by how authentic its truth may seem because others will be speaking their truth quietly and clearly. And you must listen to them as well.

Speaker B: Do I have to snatch a pebble from your hand now?

Speaker A: Go ahead, snatch the pebble from my.

Speaker B: Wow. You got some quick reflexes, man. All right, I.

Speaker A: You can do it. You can do it.

Speaker B: Oh, snap. You have some really, like, uncannily fast reflexes. Like there shouldn't be.

Speaker A: Whoa. You are not ready, my son. Come back another time. Okay, one last fun fact about the son.

Speaker B: Okay.

Speaker A: All right. If we're about 8000 miles across, right? If you look up the diameter of the sun it'll give you something like 864,000 miles. Something like that.

Speaker B: Jesus.

Speaker A: Okay. All right. So now let's round that down just so the numbers come out fun. Pull it 800,000 miles across.

Speaker B: 100 times bigger.

Speaker A: It's 100 times. 100 times across. So you can take earth and position it 100 times back to back, belly to belly. And you'll span the width of the sun.

Speaker B: Wow.

Speaker A: Okay, 100 times. Now, by the way, that's about the size of sunspots. So the sun has blemishes larger than earth, and the earth, just so you know.

Speaker B: Jeez.

Speaker A: All right. So now, if it's 100 times across, that means it's also 100 times deep.

Speaker B: Deep, yeah.

Speaker A: It would be a hundred times top to bottom. So how many earths could fit into a hollow?

Speaker B: Into the sun.

Speaker A: Into the sun.

Speaker B: That's 100 times. 100 times 100.

Speaker A: Give me what that number is.

Speaker B: 100 cubed.

Speaker A: Thank you, judge, for that precise response. 100 times 100 is 10,000.

Speaker B: Right.

Speaker A: And 100 times 10,000 million. And then that's it. I did it three times already. Okay, so the sun were hollow. You could pour a million earths into it.

Speaker B: Wow.

Speaker A: And still have room left over.

Speaker B: Damn.

Speaker A: Yep. Yet for millennia, people were walking around saying the sun and the moon were like the same thing on the sky, and we're the center of the universe. If you read Genesis, literally, the earth was created before the sun and the moon. And when we came to these realizations over the millennia, over the centuries, it was like, no, we're not making Earth first and then assembling something a million times larger and have it orbit the earth.

Speaker B: Right?

Speaker A: That ain't how the universe works.

Speaker B: We're not that special.

Speaker A: All right, Chuck, that's it.

Speaker B: There you go.

Speaker A: That's all I got for you.

Speaker B: Well, the most impressive thing about this explainer is your freakishly fast reflexes. I have to say, it makes no sense at all.

Speaker A: All right, there's been another explainer for startalk. This one, what is the diameter of the sun? Until next time, keep looking up.