The Most Famous Eclipse in History with Joe Rao

What is going on with eclipses? Neil deGrasse Tyson and comedian Chuck Nice learn about some upcoming eclipses and famous eclipses of the past with meteorologist and eclipse chaser, Joe Rao.

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

• 0:00Chuck Nice?

  Today's episode is brought to you by Vayanas. Want a chance to win a free telescope? Then you'll want to keep listening to this episode. Let's start the show.

• 0:08Speaker 01

  And everything is changing moment by moment as the shadow is passing over you. You see everything shifting and changing and it just, it's just an incredible and an amazing sight to see.

• 0:18Chuck Nice?

  Yes, but Joe, Joe, tell us how you really feel about this.

• 0:21Speaker 01

  That's what I'm saying.

• 0:25Neil deGrasse Tyson?

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

• 0:38Neil deGrasse Tyson?

  This is StarTalk. Neil deGrasse Tyson, your personal astrophysicist. Guy with me Chuck Nice. Chuck, how you doing, man? Hey, hey, hey Neil, what's happening? So today, we're going to talk about eclipses. Solar eclipses to be precise. Wow, look at that. Nobody doesn't love a good solar eclipse. Yeah. And the press is all over them when they occur. Boy, oh, boy. Yeah, they, they can't get enough of them. And you know, there's some interesting history of science behind solar eclipses. Yeah. I thought I'd tell you about that. Okay. I'm always, always down for that. So first of all, eclipses, these eclipses happen every couple of years. They're not rare in spite of what newspapers tell you. Yeah, yeah. Okay. Everybody likes to make a scene, yeah.

• 1:22Neil deGrasse Tyson?

  Okay, people want to think something happens in the sky and you're special because you're alive to see it. And they'll say, then it won't repeat for another, okay? Yeah. And it repeats in a couple of years, right? But those, it won't repeat for your location for another 500 years. Right. So get in a car. There you go. Right. Yeah, basically. All right. So in 1905. Okay. We'll go back. Albert Einstein publishes the general theory of relativity. Yes. Which allows us to think about space and time in the presence of accelerations.

• 2:05Neil deGrasse Tyson?

  Alright, the, the original special theory of relativity was for constant velocity.

• 2:09Chuck Nice?

  Right.

• 2:10Neil deGrasse Tyson?

  You're not changing your speed or direction. So it was a simplified case, and there's a whole set of equations that go with it. But, what it needed was the general case. Suppose you're accelerating.

• 2:21Chuck Nice?

  Right.

• 2:21Neil deGrasse Tyson?

  Suppose you're in a strong gravitational field. Do these equations help you with that? No. It took Einstein another ten years to figure out how to extend the special relativity into the general case.

• 2:35Chuck Nice?

  Hmm.

• 2:36Neil deGrasse Tyson?

  1915, he publishes The General Theory of Relativity. Alright. And what it said was that the fabric of space and time is warped in the vicinity of strong fields of gravity. In fact, it's warped in the vicinity of any source of gravity, but you only really begin to notice it for strong sources of gravity, especially black holes, which weren't discovered yet or invented yet. But, in a modern example, that's the extreme case of this going on. Alright. So, what do we have? Oh, by the way, before this, the planet Mercury, its orbit around the sun was not following Newton's laws.

• 3:22Chuck Nice?

  Hmm.

• 3:23Neil deGrasse Tyson?

  Something's wrong. Are Newton's laws, do they fail? Or, maybe there's another planet that you can't see, that's tugging on it that we're not including in our equations. Well, why can't you see it? Oh, cuz, well, maybe it's just orbiting too close to the sun, and it's always lost in its glare. Okay? So astronomers were perfectly content explaining away Mercury's anomaly by invoking a planet whose gravity was affecting it. We were perfectly happy with that. We even named the planet. We called it Vulcan.

• 3:57Chuck Nice?

  Oh, I didn't know it was right here, right here in our own solar system.

• 4:02Neil deGrasse Tyson?

  We got one, right. Alright, alright, alright. So, during a total solar eclipse, the sun is blotted out by the moon.

• 4:11Chuck Nice?

  Right.

• 4:12Neil deGrasse Tyson?

  If there's a planet orbiting close to the sun... You ought to be able to see it. Right. When you wouldn't otherwise be able to see it under normal conditions. Right. So, ever since we learned that Mercury's orbit was misbehaving, we waited for solar eclipses to look for the planet Vulcan, and we never found it. Well, it must be behind the sun, or maybe exactly in front of that's why. It's rather dodgy Vulcan. It's a dodgy planet, alright, so we, so we were happy to sort of keep making excuses for it. Okay. Hmm. Let's keep going. So now Einstein's general theory of relativity gets published,

• 4:56Neil deGrasse Tyson?

  and it predicts that light passing by the sun will feel the gravity of the sun and its path will be bent as it goes by. Right. Because of the curvature of space and time. Now I have two things to look for. Vulcan. Vulcan. What, whether we're gonna bend the light around the sun. Alright, so this all happened in 1915. Sir Arthur Eddington, probably the world's first astrophysicist, if you wanted to. We had astronomers up until him, and after that, he, my boy, had some physics growing with inside him. Okay? So, he said, "I'm gonna test this."

• 5:40Neil deGrasse Tyson?

  You say the sun has such a strong gravity, it's gonna bend the light of us, I'm gonna test it. So he's gonna use a solar eclipse to test it. So you wanna take a picture of the star field when the sun is nowhere to be found. Right. Then wait six months. Now the sun is exactly in the middle of that star field during a total solar eclipse. And now, you take an image of all those stars again and see if their positions have shifted. Hmm. This is brilliant. It is. Okay? Well, there's an eclipse in 1916. Did he do the experiment then? No. There was an eclipse in 1918. Did you do the experiment then? No.

• 6:25Neil deGrasse Tyson?

  Why not? Um, 16 and 18, cuz, cuz it's like wine, an odd year is better.

• 6:35Neil deGrasse Tyson?

  Chuck, how soon we forget. The world was at war. Oh, damn, that's right. To resources and boats and chips and tools and food. The world was at war. Wow, that's right. So, World War I, back then, the Great War, as they called it. The war to end all wars. Right, right, right. We see how that turned out. Right, so he had to wait for the war to end. So, the next eclipse after that was 1919. So, May 29th, 1919. He mounts an expedition to observe the eclipse. And he does so. And he makes the measurement of the positions of the stars.

• 7:17Neil deGrasse Tyson?

  And he discovers, yes, the positions of the stars are, have shifted from where you expected them to be because they are curving in the presence of the fabric of spacetime being distorted because of the sun. Look at that. And people said, holy cow, if Einstein's general theory of relativity is true, then let's recalculate Mercury's orbit. And when you do that, you find out that general relativity is what's messing up Mercury's orbit.

• 7:53Neil deGrasse Tyson?

  You don't need to, Vulcan evaporated overnight. Right. With the confirmed Einstein's general theory of relativity. So, we lose Vulcan, we gain the confidence in the general theory of relativity. It's all because of Sir Arthur Eddington, a brilliant physicist. I think he was from Cambridge, Cambridge, England, University of Cambridge. And he's the one who said, before he knew anything about thermonuclear fusion, he's the one who said, when people asked him, well, where do we get these heavy elements? He said, maybe they happen in the centers of stars. Well, we don't think it's hot enough in the centers of stars. And he said,

• 8:35Neil deGrasse Tyson?

  Maybe so, but if this is gonna happen anywhere in the universe.

• 8:40Chuck Nice?

  It would have to happen. Yeah, I mean, let's, and then listen, and no disrespect to Sir Eddington, okay? It's not a hard stretch to make, I mean.

• 8:51Neil deGrasse Tyson?

  Well, I, because we calculated the temperatures of the centers of stars.

• 8:55Chuck Nice?

  Right.

• 8:55Neil deGrasse Tyson?

  And it was not hot enough to, to fuse. What, you know, we needed, we needed quantum physics.

• 9:00Chuck Nice?

  Right.

• 9:01Neil deGrasse Tyson?

  Which was the decade that followed, the 1920s.

• 9:04Chuck Nice?

  Right.

• 9:04Neil deGrasse Tyson?

  By the way, Chuck, we are living in the centennial decade. Centennial decade of a watershed decade in the history of physics.

• 9:13Chuck Nice?

  Right.

• 9:13Neil deGrasse Tyson?

  The 1920s, where quantum physics was developed, where Hubble discovered that the Milky Way is not alone in the universe. There are other galaxies, and when Hubble discovered that the universe is expanding.

• 9:25Chuck Nice?

  Right.

• 9:25Neil deGrasse Tyson?

  All of that happened in the 1920s.

• 9:27Chuck Nice?

  Wow.

• 9:28Neil deGrasse Tyson?

  Just thought I'd put it out there.

• 9:29Chuck Nice?

  That and a bunch of drinking and partying.

• 9:32Neil deGrasse Tyson?

  Ah, the roaring twenties.

• 9:34Chuck Nice?

  Roaring twenties, look at that.

• 9:36Neil deGrasse Tyson?

  Yeah, not everybody was roaring, you know, at the speakeasies, right?

• 9:39Chuck Nice?

  Right.

• 9:40Neil deGrasse Tyson?

  So, that's the just bit of the background physics on that particular, for that reason, it's the most famous eclipse in physics.

• 9:47Chuck Nice?

  Right, yeah.

• 9:48Neil deGrasse Tyson?

  The 1919 eclipse.

• 9:49Chuck Nice?

  Super cool.

• 9:50Neil deGrasse Tyson?

  Yeah, yeah, so, all right, that's all I gotta tell you.

• 9:53Chuck Nice?

  That's amazing, I love it.

• 9:55Neil deGrasse Tyson?

  So Chuck, you noticed that there was an eclipse in 1916 and 1918?

• 10:01Chuck Nice?

  Yep.

• 10:01Neil deGrasse Tyson?

  And he got the one in 1919.

• 10:03Chuck Nice?

  Right.

• 10:03Neil deGrasse Tyson?

  Right, so, like I said, eclipses aren't rare.

• 10:06Chuck Nice?

  Not rare.

• 10:07Neil deGrasse Tyson?

  Okay.

• 10:08Chuck Nice?

  Not a big deal.

• 10:08Neil deGrasse Tyson?

  And we're having this conver- we're having this conver-

• 10:10Chuck Nice?

  Cosmologically, it's a bus schedule, like, let's not, let's not get crazy, let's not get crazy. Okay. Oh my God, we missed the bus! Ah, what are we gonna do? We're stuck here forever, we missed it! Like, nah, man, there's another one coming, don't worry, it's all good.

• 10:29Neil deGrasse Tyson?

  We got this.

• 10:32Neil deGrasse Tyson?

  Bus schedule, so, we're recording bits of this coming on to the beginning of October, the next eclipse is October 14th.

• 10:39Chuck Nice?

  Look at that.

• 10:40Neil deGrasse Tyson?

  Look at that, and check your bus schedule after that.

• 10:43Chuck Nice?

  Right.

• 10:43Neil deGrasse Tyson?

  Go out there, look at it right now, look at it right now.

• 10:45Chuck Nice?

  All right.

• 10:46Neil deGrasse Tyson?

  There it is, okay, next one, April.

• 10:49Chuck Nice?

  Oh, okay, mine said 4/20.

• 10:56Neil deGrasse Tyson?

  What notes are around you, Jeff?

• 10:57Chuck Nice?

  I don't know.

• 10:58Neil deGrasse Tyson?

  Okay.

• 10:59Chuck Nice?

  Yeah. Wow, so look at that, yeah.

• 11:01Neil deGrasse Tyson?

  Yeah, so we got eclipses coming and going. And so, well, I know a thing or two about eclipses. I have a friend and a colleague who knows more about eclipses than perhaps anyone else in the world.

• 11:16Chuck Nice?

  Okay.

• 11:17Neil deGrasse Tyson?

  Now, how do you get to that list? I think he may be the person of all living people on Earth

• 11:25Chuck Nice?

  Uh oh.

• 11:26Neil deGrasse Tyson?

  who has seen more eclipses than anybody else.

• 11:28Chuck Nice?

  That is... Oh, I'm wondering if anybody has attempted to quantify that record.

• 11:36Neil deGrasse Tyson?

  Yeah, that's a way to quantify. So, add up how many minutes in the moon shadow you have lived.

• 11:42Chuck Nice?

  Ooh, that's the title of his book!

• 11:45Neil deGrasse Tyson?

  Ah, no! I guess that is a book title, isn't it?

• 11:48Chuck Nice?

  Minutes in the Shadow of the Moon.

• 11:50Neil deGrasse Tyson?

  Ooh.

• 11:51Chuck Nice?

  That's a great title. Minutes in the Shadow of the Moon.

• 11:54Neil deGrasse Tyson?

  We'll tell him that when we bring him on.

• 11:56Chuck Nice?

  Yeah.

• 11:56Neil deGrasse Tyson?

  That's right. So, yeah, so he's a friend and a colleague. His name is Joe Raum. And he's a meteorologist. He's an associate at the Hayden Planetarium at the American Museum of Natural History. And meteorologist, he actually delivered the weather. He was like the TV weatherman for multiple places in the region, but News 12, in Long Island and I think in Westchester. But, so, by the way, when you're an astronomer, you also have to be really good at knowing the weather.

• 12:25Chuck Nice?

  Yes.

• 12:25Neil deGrasse Tyson?

  Because it's not just whether it'll rain, it's whether or not there are clouds, right? We care if there are clouds.

• 12:32Chuck Nice?

  Right.

• 12:32Neil deGrasse Tyson?

  Whereas you can still hold your picnic under the clouds, right? So, our standards for the weather that we need are much higher than that of basically everybody else.

• 12:41Chuck Nice?

  Right.

• 12:42Neil deGrasse Tyson?

  I put that out there, yeah. So, there it is. Eclipses here, eclipses there, eclipses everywhere.

• 13:02Chuck Nice?

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• 13:44Chuck Nice?

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• 14:21Chuck Nice?

  free. That's Vayanas.com/StarTalk, V-A-O-N-I-S.com/StarTalk. Winners will be notified by November 3rd, 2023.

• 14:43Neil deGrasse Tyson?

  So Joe, Chuck and I were in conversation before we brought you on, and weren't you at one point, one of the world's leaders in how many minutes of totality you have experienced? How many minutes in the moon shadow? That you've lived?

• 14:58Speaker 01

  I've been in the uh in the moon shadow for just over thirty minutes. I've seen I've been to thirteen total eclipses, which sounds like a lot, and for many people it is. And it would have me it would have put me at the very top of the list fifty years ago, but I must tell you, Neil, uh that now in the year twenty twenty-three, I'm just a piker. There are some folks out there who have traveled to twenty-five, thirty, even thirty-five total eclipses. So I'm way, way behind the head of the pack. But still, I've I've seen a decent number and I've experienced totality enough so that as I've always told people, when you see your very first one, watch out because you instantly become addicted and you want to go see another one. And I've I've done that. I've I've seen, again, more than my fair share.

• 15:43Neil deGrasse Tyson?

  Did you ever cheat and go on? Do you remember they used to have the SSTs, the supersonic transport that would chase the the the shadow? And you'd be like in the shadow for an hour or something back when the SST was running? Were you ever lucky enough to do one of those?

• 15:58Speaker 01

  No, unfortunately. Well, I have been on aircraft, which we have attempted to outraise the shadow, which of course we never really did, but we were able to extend the time of the total eclipse by a little bit. The Concorde did, in fact, race the shadow of the moon back in nineteen seventy-three and stayed in the shadow for an incredible seventy-three minutes over Africa. But of course, now we don't have the Concorde anymore, and I am not sure whether or not any supersonic transports are being uh developed so that we could do that again sometime down the road. But seventy-three minutes, that's that's that's one heck of a long extension of totality.

• 16:35Neil deGrasse Tyson?

  Yeah. Who who paid that gas bill?

• 16:37Speaker 01

  I know.

• 16:37Neil deGrasse Tyson?

  God, God.

• 16:41Neil deGrasse Tyson?

  That was one expensive flight, man. So so just to put some numerics on this, so the moon's shadow, correct me if I'm wrong, Joe, is what's dragging across Earth's surface, but Earth is also rotating in that same direction. So there's the speed of the shadow and there's the speed of the shadow. On the turning earth. And I always get those numbers mixed. It's about eight hundred miles an hour or something. Does that feel about right to you?

• 17:05Speaker 01

  Well, the the moon and its shadow are moving through space at about its diameter of the moon, about twenty one hundred miles an hour. And you're right. When we have that moon shadow interact with the turning earth, right around the equator is where the the earth can keep up with the shadow. The at the equator, the earth is turning at about a thousand miles per hour. So the longest total eclipses, the ones that last five, six, seven minutes or more, those are the ones that occur near the tropics. As you have eclipses that occur further north up in the temperate latitudes or up toward the polar regions, the eclipses tend to be shorter because the earth just doesn't move fast enough to keep in touch or keep in the same path as the as the shadow of the moon.

• 17:48Neil deGrasse Tyson?

  Okay, so our location at New York, we're going, we're having this conversation in New York City. At our latitude, we're going east about eight hundred miles an hour. So that you would subtract that away from the moon speed, and that would be the effective speed of the moon shadow as it crossed over my head. That's that's the calculation you would do, right?

• 18:07Speaker 01

  Absolutely. Correct. A little bit of spherical geometry coming into play here. But at the latitude of New York, there was once, back in the eighteen hundreds, I think eighteen oh six, there was a total eclipse of the sun that passed over central New York, passed over Cooperstown, by the way, the baseball Hall of Fame capitol of of the United States. And that eclipse lasted about five minutes. So that's about as long as you could hope for at these latitudes, at the latitude of New York, forty or forty one degrees north, is a five minute eclipse as opposed to being down near the tropical areas, near the equator, where you can have as long as a seven and a half minute total solar eclipse.

• 18:47Neil deGrasse Tyson?

  Hmm. In fact, I, the longest eclipse eclipse I ever saw was the nineteen seventy three eclipse. And I saw it on board the SS Canberra. At sea, which was a very good place to be because you can say, oh, it's going to be cloudy where we originally targeted. Turn on the engines, let's go somewhere else. But if you pitch tents on the ground and the overcast goes over, you're kind of stuck. So where did you see the 1973 eclipse?

• 19:13Speaker 01

  Believe it or not, I was not in the totality path. I was in Madrid, Spain. So I had, I had a, I, I, I saw a partial eclipse, but I did not get a view of the total eclipse of the sun.

• 19:24Chuck Nice?

  Yes, but you, but you were in Spain. So you, you, you know, it's kind of a wash there. It balances it out. It balances out, you know?

• 19:34Speaker 01

  By the way, by the way, in, in 2026, only a few years from now, a total eclipse of the sun will be passing over Spain. So that'll be a good place to see that, that totality. I did, think of it this way, I was about 50, 52 or 53 years too early when I went to Spain in 1973.

• 19:52Neil deGrasse Tyson?

  So for that 1973 eclipse, I was, we were close enough to the equator for this effect to matter, Joe, and my, I saw six minutes and 19 seconds of totality. And which was less than had I gone further, closer to the equator along its path, deep into Africa, where they got, I think, seven minutes and 20 seconds, something like that. Let me tell you how long it was. I finished a roll of film in my camera, rewound it, removed it and reloaded and finished a second roll of film.

• 20:22Speaker 01

  Wow.

• 20:23Neil deGrasse Tyson?

  Back when film was a thing, for the youngins out there.

• 20:26Chuck Nice?

  Yeah, I was about to say, what, no, what is this film?

• 20:30Neil deGrasse Tyson?

  So Joe.

• 20:31Chuck Nice?

  What is that?

• 20:31Neil deGrasse Tyson?

  So Joe, there are different kinds of eclipses. Tell me about, well, we know a total eclipse, the moon completely blocks the sun. But then, you know, in October 2023, there's an annular eclipse. And nobody knows what these are. Could you just tell people what it is?

• 20:49Speaker 01

  First of all, it's an annular, not an annual eclipse. Annular is from the Greek ring shaped, and that's exactly what the sun is going to morph into at the middle part of the eclipse. It's kind of like a penny on a nickel effect. If you think of the sun as the nickel and the moon as a penny. The moon on October 14th, a Saturday, by the way, is going to be just a little bit too far from the earth for it to completely cover the disk of the sun. And so, when they are all aligned, the moon is exactly aligned with the sun. You will see a ring of sunlight shining around the silhouette of the moon. And that's interesting. In fact, it's rather unique if you've never seen one before. But it pales, it really does.

• 21:34Speaker 01

  It pales in comparison to seeing a total eclipse. Because during a total eclipse, when you knock out all of the sun's light, it really is comparing an annular to a total eclipse is like comparing night to day. It is that different.

• 21:47Chuck Nice?

  So the annular eclipse is kind of mood lighting.

• 21:54Chuck Nice?

  Just kind of let's dim the lights, maybe. Put on some Barry White or some soft music and.

• 22:01Speaker 01

  You are absolutely right, Chuck.

• 22:03Neil deGrasse Tyson?

  Yeah, so it's still technically a partial eclipse.

• 22:07Speaker 01

  Now, I call, you know, I call annular eclipses, you know, unique partial eclipses. It is, it is a partial eclipse. It's nothing else. Uh, because you're still going to have a portion of the sun visible. And by the way, during the peak phase, when you have that ring in the sky, you can't look at the ring unless you have either one of those special eclipse glasses or welder's glass, or you can project the image of the sun because it's dangerous.

• 22:33Neil deGrasse Tyson?

  It's still the sun you're looking at.

• 22:35Speaker 01

  Absolutely.

• 22:36Neil deGrasse Tyson?

  Whereas in a total eclipse, in the time the sun is totally covered, there's no sun there, you remove the eye protection and there it is. Right.

• 22:45Speaker 01

  Absolutely.

• 22:46Neil deGrasse Tyson?

  So Joe, you know, we got questions from our Patreon supporters. And I would like to go to those. They knew that you were coming on and knew about your expertise. And so Chuck gathered them. So what do you have for us, Chuck?

• 22:59Chuck Nice?

  Well, let's go for it. Hi Neil, hi Joe, hi Chuck. I'm Steven asking from Newark, Ohio. What is the most interesting thing you know about eclipses? Mine is the fact that we exist in a timeline that eclipses can occur. I appreciate it and thanks to all of you for all you do.

• 23:19Neil deGrasse Tyson?

  Love that question.

• 23:20Chuck Nice?

  So what's your most interesting eclipse?

• 23:24Speaker 01

  Well, you know, when you've seen thirteen of them, each one, and it's that they're kind of like, for me, they're kind of like snowflakes. No total eclipse is alike or similar to any other. The most dramatic eclipse, I think, for me, was one I saw in nineteen seventy-nine in Montana, where we saw the shadow of the moon, two to three minutes before totality. It looked like a tidal wave of darkness. And believe me, if you have never seen or experienced a total eclipse before, and all of a sudden, you're looking toward the western sky, and you're looking at what appears to be a time lapse of a severe thunderstorm. Of course, over, you know, maybe twenty, thirty minutes, you see the sky gradually darken as the thunderstorm approaches. But imagine now squeezing that into a timeline

• 24:07Speaker 01

  of just a couple of minutes. The darkness just charging towards you, and really, there's nothing that you could do about it. You can't stop it, obviously. And here comes this shadow, which suddenly just engulfs you. It's like throwing a gigantic blanket over your head. And really, in the final thirty seconds before totality, it's kind of like, you know, you turn down a dimmer switch. All of a sudden, the sky is dimming, and all of a sudden, you begin to see the planets pop out into view, brighter stars popping out. And when that last little bit of the sun disappears, and of course, the moon is a rugged surface, and so just before totality, you see these little beads that are called Bailey's beads. And then, one final solitaire of light, if you will, and with the corona of the sun

• 24:52Speaker 01

  beginning to appear, it looks like a diamond ring in the sky. How dramatic an effect that is. And then that goes away, you have the corona, you're suddenly enveloped in the weirdest light that you have ever experienced in your entire life. I can't even tell you. You know, you may have seen beautiful sunrises and sunsets, and unusual sky colors, but there really is nothing to compare to having totality sweep over you. All around the horizon, the sky appears like a saffron color, high above your head, kind of a navy blue in color. And everything is changing, moment by moment, as the shadow is passing over you, you see everything shifting and changing, and it just, it's just an incredible and an amazing sight to see.

• 25:36Chuck Nice?

  Yes, but Joe, Joe, tell us how you really feel about this.

• 25:41Neil deGrasse Tyson?

  Joe's got it real bad. He's got it bad on that one. Amazing. That was amazing. So I was in Idaho, in the mountains of Idaho in 2017. And I looked for the shadow approaching. And it is scary, frightening and exhilarating all at the same time. But I have to tell you, Joe, just for others to know. Only when you've seen eclipses before, do you have the luxury to not look up 30 seconds before totality. You know that there's other stuff to notice. And so you look down and around. Most people in their first time, they can't possibly notice that, Joe, right?

• 26:24Speaker 01

  Well, there's so many different things that are happening. You're absolutely right, Neil. About 30 seconds to a minute before, there are people who have spread a white sheet on the ground because there are weird looking shadows called shadow bands that are flickering across that sheet. And the reason why we see them just before totality and right after totality is that the sun just before totality is suddenly a thin filament of light. Now, you know that when you look up at the sky at night and you see the stars, they appear to twinkle. They twinkle because the light, the little light beams coming from the stars are passing through our atmosphere and are being distorted by our turbulent atmosphere. So that gives the effect of a twinkling effect. Now, the sun does not appear to twinkle when it's when it's out in full view because it's a full disk.

• 27:09Speaker 01

  But when we have it narrowed to a thin, very thin, narrow sliver of light, then the atmosphere, the turbulence of the atmosphere allows that to kind of interfere with that thin sliver. And what you see there on the ground are, again, really waves of light and dark that are racing across the sheet or racing across the ground. And that's, that's an effect which, you know, really is kind of a, there was a total eclipse of the sun in India back in 1980. And people, the uninitiated, who were looking down on the ground during the moment just before totality, they were screaming, "The ground is on fire. The ground is on fire. Look at what's happening to the ground." It's just another one of these amazing things and amazing effects that happen

• 27:52Speaker 01

  right around the time when the sun is getting ready to. Go away for a relatively short interval of time.

• 27:58Neil deGrasse Tyson?

  Yeah, so the luxury of knowing what to look for rather than just staring up at the at the night sky.

• 28:03Speaker 01

  Yes.

• 28:03Neil deGrasse Tyson?

  Uh, yeah, totally true. And so for me, what I like is, what's that, can that, do I get to answer that question too, Chuck, do you think?

• 28:11Chuck Nice?

  Yeah.

• 28:13Neil deGrasse Tyson?

  Say it like that. Say it like that. Uh, just that when you're in a lightly treed area, like you have the shade from a couple of trees, and you see these sort of dots of light, this modeling on the sidewalk, I'm in the city, so the sidewalk, the light is on the sidewalk. You say, that's just light, that's just sunlight peering through. There's more than that. It's actual images of the round sun on the sky that are being projected through a pinhole effect onto the ground. And you know this because if there's an eclipse going on, and you look back at that light, it all have these little crescents.

• 28:53Neil deGrasse Tyson?

  And you can watch the eclipse unfold on the ground. And, and Joe, I saw someone in Sky and Telescope, they took a colander from the kitchen, which has hundreds of holes on it, right?

• 29:04Speaker 01

  Right.

• 29:04Neil deGrasse Tyson?

  And then they held that up in the eclipse, and you see all these hundreds of little eclipselets. Did I say that? Eclipselet? Is that allowed?

• 29:11Chuck Nice?

  Nice.

• 29:11Neil deGrasse Tyson?

  Okay. So that's what my favorite part is seeing the, the multiple images of eclipses on the ground made by things that are just otherwise shadows of leaves that you wouldn't otherwise know to think about.

• 29:23Speaker 01

  My wife and I had dinner at a diner just about a week ago, and I had chicken noodle soup, and they brought it along with some saltine crackers. And I took the crackers and I put it in my pocket. She says, what are you doing? I said, I'm saving this for the eclipse that's coming up. Because, because you can use-

• 29:40Neil deGrasse Tyson?

  Joe, can't take you anywhere. Can't take you anywhere, Joe.

• 29:43Speaker 01

  You could use, you could use a saltine cracker, which has these little holes in it, use that and project the image of the sun through the holes, and you can, there, you have, you know, a little eclipse projector using a saltine cracker.

• 29:57Chuck Nice?

  Yeah, yeah. Doesn't work with a Ritz, though.

• 30:01Neil deGrasse Tyson?

  But Ritz, well, do Ritz have holes? They, they, yeah.

• 30:03Chuck Nice?

  Yeah, they do.

• 30:04Neil deGrasse Tyson?

  They do have holes.

• 30:04Chuck Nice?

  But they don't go all the way through.

• 30:06Neil deGrasse Tyson?

  Yeah. Oh, okay.

• 30:06Chuck Nice?

  Saltines, saltines are pierced all the way through.

• 30:08Speaker 01

  I didn't know that Chuck was, Chuck was a cracker expert here.

• 30:13Chuck Nice?

  More, more than, more than you know, Joe.

• 30:19Chuck Nice?

  Let's move on to the next thread real fast. Okay, yeah, there you go. By the way, let me just say, Neil, you just answered Justin from Ontario, Canada's question without even knowing it. And he asked the exact question of why is the image on the ground when it's projected through leaves? And he ended, Justin from Ontario, Canada, ended by saying, Neil, you are like the stars to me, I look up to you. Oh, thank you. Just wanted to give him credit for his question that wasn't even asked, but was answered. Okay, all right, you got it. Fantastic. Keep it going.

• 31:01Chuck Nice?

  Okay, so this is Liam from Rhode Island. He says, do you know if there's any effect of solar eclipses on wildlife? I am wondering if there have been any interesting behaviors that have been documented when the sun goes dark in the middle of the day. All right, Joe, what do you got for that?

• 31:19Speaker 01

  Well, we have had indeed studies on that very subject. In fact, in 1925, when there was a total eclipse of the sun right here in little old New York, there were people at the Bronx Zoo who observed the animals who took note, the deer, for example, raced around in panic just before the sun get totality in the cage where they kept the chimpanzees and monkeys. They were, you know, having all kinds of fun, jumping around, everything else. But then, just as totality was about to approach, they got very, very quiet and they looked around and then they almost looked like they had a scared look on their face. They said, what's going on here? It's getting, it's getting dark. But the most interesting thing was that there was a very rare bird called the bird

• 32:04Speaker 01

  of paradise. And the effect of the eclipse on that bird was such that during the timeframe during totality, the bird actually stuck out its neck real far and extended its wings out and just was going up and down, up and down. And the people who study these birds. Never saw anything like this before. It does have an effect. Chickens go to roost. In fact, probably the most famous story about this involves Thomas Edison, the great inventor. He saw a total eclipse of the sun in Wyoming, just as you went to Wyoming, Neil, back in 1879. And he had a device that he was going to use to measure the temperature of the corona that he had just invented called the tazimeter.

• 32:47Speaker 01

  And he was looking around for a place where he could set up, and he saw an old barn house. And he looked around, there's nothing in there, and he says, oh, this is great. And it'll protect me from the wind and provide me with shelter. So he set his instrument up, and here's totality coming. It's only a few seconds away, and all of a sudden, from all directions, Edison got bowled over by chickens. Chickens that were coming from all directions and going back into the barn house or the hen house to go to roost because they thought that nighttime was coming. And so all of a sudden, that was one of the world's great chicken stories, I might add.

• 33:25Neil deGrasse Tyson?

  There was also an eclipse that went across near South Africa and went over the Kruger Game Reserve. And so there are people who were, I don't know what results came out of that, but the Kruger Game Reserve where, you know, there's hippos and giraffes and, you know, the things that are in half the dioramas of the American Museum of Natural History, the watering holes. So I knew people were going there to see what the effect is. I would say the animal that behaves the weirdest of them all is humans. We spend scads of money to go into the shadow, take boats, trains, planes, and automobiles, and we've got to be the weirdest behaving creature out there.

• 34:05Speaker 01

  The first 30 seconds of totality, as long as the totality lasts at least 30 seconds, but the first 20 or 30 seconds, people just scream their heads off. And then, then after the initial shock and the initial screaming and yelling of, look at that, look at that. Everybody quiets down, and if they have an experiment they're conducting, looking at temperature sensors or whatever, or taking pictures, everything gets very quiet. And then, just as you approach the end of totality, you know, you start seeing... The interesting thing about the end of totality, there's like a red flag that comes out that warns you that totality is about to end. The chromosphere, which is the... The innermost part of the sun's atmosphere, which glows kind of a beautiful reddish or electric pink color,

• 34:50Speaker 01

  first begins to emerge. And that emerges maybe about five or 10 seconds before the actual chromosphere, the first part of the sun's surface emerges and comes back out. And of course, then you have to put your glasses or your protective devices back on your eyes. It is an amazing, an amazing spectacle, literally from start to finish.

• 35:32Chuck Nice?

  Chuck, give me some more. OK, here we go. This is Will. And Will says, greetings, Joe, Neil, Chuck. What is the earliest record of an eclipse? And what might have prehistoric humans thought was going on? Thank you all so much for what you do. Will from Lexington, Kentucky. Hmm. Any speculations there, Joe?

• 35:54Speaker 01

  October 22nd in the year 2137 B.C., believe it or not. We have records of, of an eclipse that occurred over China. And the interesting thing about that eclipse, Chuck and Neil, was that back then, in those days, they actually had court astronomers. Now, back in 2137, they, B.C., they could not do any specific calculations. But the court astronomer's job was to constantly watch the sky, day and night, for anything unusual. And in the case of an eclipse, if you saw that there was an eclipse taking place, you immediately alerted the emperor, who in turn alerted the people, who would then beat drums or shoot rockets up into the sky to try to frighten the dragon.

• 36:36Speaker 01

  They thought that that was what an eclipse was, was taking place, an invisible dragon eating away at the sun. And in 2137, in 2137, in 2137 B.C., unfortunately, the court astronomers apparently were asleep. Either they got drunk the night before and didn't quite wake up in time, but didn't alert anybody that an eclipse is in progress. And here comes the eclipse, and here it's getting dark, and everybody is screaming and yelling and running around. Shooting rockets, they, they, and believe it or not, they did actually scare away the dragon. That methodology always worked.

• 37:13Neil deGrasse Tyson?

  It works every time.

• 37:14Speaker 01

  It worked every time.

• 37:15Neil deGrasse Tyson?

  Yeah.

• 37:15Speaker 01

  But after the eclipse was over, the emperor brought the court astronomers to him and said, "You have sinned an awful sin. You did not warn us about this event. You didn't tell us that the dragon was coming and eating the sun, and so you must face the ultimate price." And they were, they were beheaded. That, that was it. And that presumably is the earliest record of a total eclipse of the sun over China, again, uh, before the Christian era, 2137 B.C.

• 37:47Neil deGrasse Tyson?

  And, and of course, China kept very good records of the nights of the sky. And that's some of the best records we have.

• 37:52Speaker 01

  Absolutely.

• 37:53Neil deGrasse Tyson?

  Around the world, going, going, going far back. I have a, I have a case where I, someone called me at my office, and they found a diary in the attic of her grandfather who had just died. And that diary was of his grandfather, who was a pastor. And if I, my timing is right on this, I, I have to recheck my numbers. But, so apparently, it describes that they are moving through Massachusetts in some kind of wagon train, okay? And the, all of a sudden, the sky got dark. And this is, by the way, described in, in Revelations. The sky gets dark.

• 38:36Neil deGrasse Tyson?

  And the pastor was certain the end of the world was near. He stopped the wagon train, got everybody off, and said, "Repent. The end of the world is near. Pray for forgiveness." Everybody got off, prayed, then it got light again, and then they felt that their prayers were answered.

• 38:51Speaker 01

  It worked!

• 38:52Neil deGrasse Tyson?

  So she asked me, "Could this have been an eclipse?" And I said... Even deeply religious pastors would have known what an eclipse was because they're educated people. An eclipse is not a new weird thing in the sky. They would see it and say that's an eclipse. Okay, so I had to conclude. Well, at first I went to verify that it was real. So I checked. I said, when would you? She said between 1760 and 1790 Massachusetts. So I went to my tables and went to my computer, found, yes, indeed, there was a total solar eclipse across New England, in whatever year it was, but I had the correct year, and that tightly localized that trip. Okay, because eclipsers are not rare, but when they do

• 39:37Neil deGrasse Tyson?

  happen consecutively, they're all around the world. So I nailed that. So I said, yes, they experienced an eclipse. But if he didn't know it was an eclipse, it must have been overcast.

• 39:47Speaker 01

  It

• 39:48Neil deGrasse Tyson?

  Because if it's an overcast

• 39:50Speaker 01

  Ah, he couldn't see, couldn't see the sun and everything just got dark.

• 39:54Neil deGrasse Tyson?

  Everything just got dark.

• 39:55Speaker 01

  I, I experienced that a couple of years ago. I went all, I went all the way down to Antarctica to see a total eclipse of the sun and down there, it's almost 24 hours of daylight in December, which is the month that I went, and we had total overcast, complete total overcast, and came the moment of totality. All of a sudden, the sky got very dark for about 90 seconds or so, and then just as quickly, it got bright again. We had a gray sky, but that was the shadow passing, passing overhead.

• 40:25Neil deGrasse Tyson?

  You froze your buns off for no reason.

• 40:27Speaker 01

  Actually, I, when I was offered the trip, I said, no, because I knew that the weather prospects for clear weather was, was lousy. But the people who put the tour together said, you're missing the point. The eclipse is the icing on the cake, but the trip itself is the cake. How many times are you going to get offered a chance to go to Antarctica? And so, so we went, my wife and I, we went, we spent two weeks down there. And I got to tell you, it was interesting. I mean, cavorting around with, we went to a place called Paulette Island, a one mile slab of rock, 200,000 penguins on that island. I mean, where, and the funny thing is, they, they, they told us, stay at least five meters away from the penguins. Do not go near the penguins. Somebody forgot to tell the penguins

• 41:12Speaker 01

  that. And in fact, if you go down to Paulette Island, they waddle up to you like a pigeon will waddle up to you in Central Park, you know, just looking like.

• 41:20Neil deGrasse Tyson?

  Wow.

• 41:22Speaker 01

  So I didn't see, I didn't see the eclipse, but I saw a lot of penguins.

• 41:26Neil deGrasse Tyson?

  Okay, alright.

• 41:28Chuck Nice?

  Yeah, that doesn't sound like a good vacation, Joe.

• 41:32Speaker 01

  It was interesting.

• 41:34Chuck Nice?

  I'm just gonna be honest.

• 41:36Neil deGrasse Tyson?

  And by the way, penguins don't poop less than pigeons do, right? So there was surely penguins poop everywhere. Alright, we got time for just maybe one or two more questions. Chuck?

• 41:47Chuck Nice?

  Okay. Hey Neil, hey Joe, hi Chuck, from the world of falsifiable hypotheses. How does a flat-earther explain a lunar eclipse? From Backwoods Oregon, expiring minds want to know.

• 42:05Neil deGrasse Tyson?

  So Joe, take a stab at that. I got something to say too, but I want to hear what you, I want you to lead off.

• 42:09Speaker 01

  A lunar, a lunar eclipse is different from a solar in that the, the moon, the sunlight provides the light that we, that allows us to see the moon, reflected sunlight. When we take away that sunlight, then the moon disappears. And the only way we could take away that sunlight is if the moon were to move into a shadow, our shadow. The earth, of course, if we, if you believe that the earth is a globe.

• 42:33Chuck Nice?

  Blasphemy!

• 42:35Speaker 01

  And a globe will cast a shadow out into space, a circular shadow. So when the moon starts moving into the shadow of the earth, you see a curved shadow moving across its face. So if this is a flat earth that we all live on, how is that possible? That we get a curved shadow moving across the disk of the moon? And so that's the best way I know to describe or to prove that we live on a, on a sphere, on a, on a circular planet.

• 43:00Neil deGrasse Tyson?

  But you, you left out an important point there, Joe, which is, it is a curved shadow no matter where the moon and the sun is on the sky during that eclipse. And so you have to ask, what is the only shape that will always give a circular shadow?

• 43:19Chuck Nice?

  A circular shadow.

• 43:20Neil deGrasse Tyson?

  And that's a sphere. Whereas a disk can give a circular shadow, but at other orientations, horizontal, then it's a straight line. So that's what we would tell flat-earthers, but they, they're not gonna listen.

• 43:35Chuck Nice?

  There you go. That's the truest lesson there, which is don't waste your time. That's the, that's the real lesson.

• 43:43Neil deGrasse Tyson?

  One more, one more. What else you got?

• 43:45Chuck Nice?

  Okay, here we go.

• 43:49Chuck Nice?

  Let's find, since we only have time for one more. Okay, here we go. G'day, Dr. Tyson, Joe and Chuck.

• 43:59Neil deGrasse Tyson?

  Okay.

• 44:00Chuck Nice?

  That's the way he says it. So anyway, but then he says Andy C here from Vancouver, British Columbia. So maybe he's just an Aussie in Vancouver.

• 44:11Neil deGrasse Tyson?

  Because only Aussies say g'day, I'm pretty sure.

• 44:13Chuck Nice?

  Yeah, that's right. And he spelled it g'day.

• 44:15Neil deGrasse Tyson?

  G'day, yeah, yeah, all right.

• 44:16Chuck Nice?

  Yeah, g'day. Anyway, a historical question here. What do we know about how ancient and early culture civilizations conceived, interpreted, and understood these rare events? Did they actually mean something? What stories and legends and myths revolved around them? What is the most interesting myth or magical moment associated with an eclipse that you would know of?

• 44:36Neil deGrasse Tyson?

  So other than the dragons eating the sun, what else is floating around there, Joe, before the era of science?

• 44:43Speaker 01

  Well, back in the year 585 A.D., there were two warring factions in the Middle East, the Lydians and the Medes. They were, they were going at each other for many, many years. And then all of a sudden, right in the middle of a battle, the sun suddenly darkened. Total eclipse of the sun took place. And both factions were so frightened at what they saw, they thought that a message was being sent to them from high above. They immediately called a truce, shook hands with each other, and never war it again. It's too bad that that can't happen today.

• 45:16Chuck Nice?

  That's a great story.

• 45:17Speaker 01

  That would be wonderful if we can, if in next, next year, if it's 2024.

• 45:22Neil deGrasse Tyson?

  Peace descends over the earth, yeah.

• 45:25Chuck Nice?

  Oh, man, that's so cool. I mean, I just love the idea that they're on the battlefield going at it, just like, I'm gonna kill you. And then the sky goes dark, they're like, hold me, hold me.

• 45:35Neil deGrasse Tyson?

  Hold me, please, hold me.

• 45:38Speaker 01

  It's kind of like a football game, playoff, playoff football game where both teams are going at each other and then trying to, you know, kill each other. And then one of the players gets hurt very seriously. And both, and then both teams come together. And they both had their heads in, they even said, I've even seen cases where both teams pray together as the guy's being carted off the field or it's maybe something like that that happened during that total eclipse back in 585 AD.

• 46:04Chuck Nice?

  Maybe they should try that prayer before the game and they would prevent something.

• 46:08Neil deGrasse Tyson?

  So Joe, in your eclipse that took place over that battle, I think there's an addendum to that eclipse, which is, we know exactly where that battle was being conducted at the time.

• 46:25Speaker 01

  Right.

• 46:26Neil deGrasse Tyson?

  And if you take modern eclipse tables and go backwards to postdict that eclipse, the eclipse lands in the wrong part of Earth. And so you say, well, could they be wrong about where they held their battle? Rarely do you not know where you're fighting other people and laying bloodshed. So they had to correct for the slowing down of Earth's rotation to properly land the eclipse in the right spot. So that is one of the longest baselines of evidence that Earth's rotation is slowing down. The eclipse stopping that battle in that moment at that location on Earth.

• 47:08Neil deGrasse Tyson?

  And so that's the moon sloshing tides on our continental shelves, been doing that forever. And you have to factor that in if you're gonna back predict eclipses into the calendar.

• 47:19Chuck Nice?

  Look at that.

• 47:21Neil deGrasse Tyson?

  Yeah.

• 47:22Chuck Nice?

  Cool.

• 47:23Neil deGrasse Tyson?

  So Joe, you carry so much eclipse expertise, and we're doing what we can to share it here, but I understand you offer virtual presentations on eclipses to libraries, civics groups, organizations, and you are available to do that before the April eclipse of next year. And from my notes here, I say it's an hour plus, of course, Q and A. So what kind of things do you do in that hour?

• 47:50Speaker 01

  I'm offering actually two different presentations. One of them is called "The Sun Will Darken" on April the 8th. We know why, there's a total eclipse, but I get into an-

• 48:01Neil deGrasse Tyson?

  With a title like that, though, you sound like you're trying to get to superstitious people.

• 48:07Speaker 01

  Well, you know, there are a lot of people, even to this day, get frightened by total eclipses. But we get into the mechanics of why we have total eclipses of the sun. And then I get into also the proper way of observing eclipses, especially the partial phases where you need some special device like welder's glass or special eclipse glasses. Or if you want to project it through a saltine cracker or through trees, leafy trees. The other, the other presentation is I call Adventures of an Eclipse, Jason. I talk about not all, but some of the crazy things that I've done in order to see a total eclipse of the sun. For example, just one example, a few years ago, I convinced a major airline to change their,

• 48:51Speaker 01

  the path of a commercial airline flight from Anchorage, Alaska to Honolulu. Delay the flight by about 30 minutes so that we could be in the proper position over the Pacific Ocean. So that everybody onboard the flight would be able to see a total eclipse. We would encounter the shadow of the moon as it passed over the Pacific Ocean. And this is just one of the many different things that I've done. I'll do anything to see a total eclipse. And that was one of the crazy.

• 49:15Neil deGrasse Tyson?

  That's a version of hijacking the airplane.

• 49:17Speaker 01

  I was about to say, you hijacked the plane.

• 49:20Neil deGrasse Tyson?

  Just say it.

• 49:20Speaker 01

  With the permission of the airline.

• 49:25Neil deGrasse Tyson?

  So we can find you at, so RAO is R A O. So we can find you at joeraowether@gmail. They can just send you an email, is that right?

• 49:33Speaker 01

  [email protected]. Just send me an email and I'll send you back all the information about how your library or how your civic group can get hold of me and have me give a presentation. And I gotta, I think I'm going to become a very busy person as we get closer and closer to that big total eclipse coming up in the spring of next year.

• 49:54Neil deGrasse Tyson?

  And when eclipses come, I hide, okay? So it's all you, you got it. It's one day, others can take over and I can rest for a day. That's how, that's how I think about it. So at joerao, R A O, joeraowether, as in weatherman, [email protected]. Joe, I'd be delighted to catch more of you through those channels. So was that everything you'd never wanted to know about an eclipse? We never knew you could know about an eclipse. Chuck, are you, are you, how are you feeling eclipse fluent now?

• 50:28Chuck Nice?

  I, you know, uh, yeah, I'm gonna say no, I still don't, there's not enough, I could do more of this.

• 50:35Neil deGrasse Tyson?

  Yeah, okay.

• 50:36Chuck Nice?

  You know, eclipses, is there anything they can't do? I mean, they, they, they, they stop battles, you know, they, they get weathermen to hijack planes. They, you know, they behead Chinese court watchers, I mean.

• 50:52Neil deGrasse Tyson?

  High and ho.

• 50:53Chuck Nice?

  Eclipses.

• 50:53Neil deGrasse Tyson?

  High and ho lost their heads.

• 50:55Chuck Nice?

  High and ho lost their heads over eclipses.

• 50:59Neil deGrasse Tyson?

  All right, Joe, great to see you again.

• 51:01Speaker 01

  Great to see you, Neil. I have a feeling we're gonna be seeing a lot more of each other as we get closer to the, uh, the big day next year.

• 51:07Neil deGrasse Tyson?

  We will totally find reasons to make that happen. All right. This has been another episode of StarTalk, a hybrid interview and cosmic queries. I love them. Chuck, always good to have you, man.

• 51:19Chuck Nice?

  Always a pleasure.

• 51:20Neil deGrasse Tyson?

  This has been StarTalk. Bill deGrasse Tyson here. As always, keep looking up.