Solar Eclipse 101

SciCafe: When Black Holes Collide - Transcript

NEIL DEGRASSE TYSON (Frederick P. Rose Director, Hayden Planetarium):

Ladies and gentlemen, welcome to the Cullman Hall of the Universe of the American Museum of Natural History.

[APPLAUSE]

All right. I'm Neil deGrasse Tyson, the Frederick P. Rose director of the Hayden Planetarium, and this is a press conference, a literal press conference, where it's open to whatever passerby wants to eavesdrop, where we are cluing the press into what will be happening on August 21st as the moon passes between Earth and the sun, and does so only for Americans.

Only residents of the continental United States will get to experience totality. We will have more information about this with my two special guests this evening. One is Joe Rao, an associate of the Hayden Planetarium. And we have Jackie Faherty, one of the resident astrophysicists here, to describe to you not only what the eclipse is about, but what programs we'll be running here as well.

We also have time for questions and answers after these presentations are done. So let's not waste any further time. Jackie, come on up. Join me in welcoming Jackie Faherty.

[APPLAUSE]

JACQUELINE FAHERTY (Senior Scientist, Division of Earth and Planetary Sciences, American Museum of Natural History):

Neil's taller than I am. I have the privilege of following Neil in this presentation, which I can tell already we have a lot of Neil fans in the audience here. But it's OK because I get to present to you one of the most exciting events that has happened across the soil of the United States in recent memory.

So I'm going to take a couple of minutes and describe what you're going to get to see, and the things that will be going on here at the American Museum of Natural History during the eclipse. So just by a show of hands, how many people have ever seen a partial or a total solar eclipse? Got lots of hands.

Now how many people have ever seen a total solar eclipse? A lot less hands. How about anybody that's ever seen a total solar eclipse on US soil? I don't see anybody's hands. OK.

So you can see how that was eliminating, and that it's been quite some time since we've had this event. So let me go over first what's actually happening. Neither the sun or the moon know what's up right now. Right now, it's just us sitting here talking about it. They don't know what's about to happen.

What's about to happen is that the moon goes around the Earth. The Earth goes around the sun. And I'll show you a video of this in just a second. We've got a screenshot of this really beautiful simulation that we've made for you of the event by the software that we have here at the museum.

So moon's going around the Earth. Earth's going around the sun. They're not perfect with each other though. The moon's orbit around the Earth is off by a couple of degrees from how the moon and the Earth system is going around the sun. So as a result, this is a fairly non-frequent occasion. It happens every 18 months or so that we get this total solar eclipse that's going to happen.

So let's start the video and start explaining what's going to happen here. So first, this is the Uniview software that we have here at the museum. We use this all the time in our planetarium dome.

And as they start the video, what you're going to see is a picture of what it looks like. Say if we were able to fly out off the surface of the Earth, and have a look at the moon, and the sun, and the Earth together. And during this period of time, during a total solar eclipse, you get the moon lined up perfectly between the Earth and the sun.

So how many people have ever looked at your own shadow? Let's see a raise of hands of shadows. You guys feel familiar with your shadow? You feel comfortable with it? Well on the day of August 21st, we are hosting the shadow of the moon across the United States.

So here's a little pullout where we're orbiting around. You saw the Earth-moon-sun system there. The sun, by the way, is about 93 million miles away, plus or minus. The moon is far less than that-- 250,000, 280,000 miles away or so.

That means that the moon is about 400 times closer to the Earth than the sun is. And as it happens, the sun is also about 400 times larger than the moon is. That's why you can walk outside, and they'll look about the same size in the sky, if you've ever noticed that.

So on the day, I had mentioned that the orbits are off by about 5 degrees, they are actually crossing the node of the moon going around the Earth and the Earth going around the sun. So we've done this little simulation where you can see this dark shadow that's passing.

The red dots are showing you cities as it crosses. We'll run the simulation one more time. So it's going to start in Oregon, and it's going to make its way across towards South Carolina. It's going to take about 90 minutes to go from coast to coast.

And the total amount of time that it takes from when you first see the shadow of the moon passing in front of the sun to when it's going to leave will change a bit depending on where you are on the earth. These are little simulations of what it might look in different areas.

So for the majority of people across the United States, you're going to see a partial. You're going to see the moon getting pretty close, or depending on how far north or south you are, some percentage of the sun will be blocked by the moon. If you're in this lucky path of totality, you're going to see the moon completely cover the sun, out pops the corona, which is this plasma that surrounds the sun that we get highly energetic particles that get tossed towards the Earth from there.

Let's just run it one more time. And I want to talk about what New York is going to get to see. So if you're lucky enough to go to the path of totality, your skies will go dark, stars will come out, planets will start to become visible that are bright. You'll probably be blown away. And I highly suggest going to see it.

How many people are planning on going to totality? OK, a bunch of people. How many people are not planning on going? So you guys will see a partial. And now, I want to speak to all of you for a second, because a partial is nothing to turn your nose at. And a lot of people have been poo-pooing, you could say, the partials.

New York City is going to get a partial. Though as we go through, it's going to actually take you through what the partial is going to look like in New York. You're going to get about 70 so percentage of the sun blocked.

As it begins here in New York, which is going to happen around 12:30 or so, depending on where you're all going to be, it starts to look-- and this is the best way I can think to describe it-- like the Death Star is moving in front of the sun. There is something wholly unnatural about watching something move in front of the sun.

So partials, while it's true you don't get that sensation of total blockage, seeing the corona come out, twilight appearing, stars coming out, which is epic, partials are still an amazing experience. Those you have to definitely protect your eyes and. I want to tell you one story about this that runs through what partials look like, as a warning and also as a note to all the kids in the audience.

The last time we had probably the best partial was in May of 1994. How many people saw that one? Hands up. Nice. It was a partial. If you were here in New York, it covered about 84% of the sun.

I was a kid, and I was in school. And the partial, the best part happened around 2:00 or so. And the school did its due diligence and taught us all about the eclipse-- what was happening, moon, the orbits, the whole thing.

The time that the eclipse was going to happen-- as a budding astronomer, I got really excited-- walking through the school, I noticed the windows were shut and the doors were locked. The school was really afraid that we were going to hurt our eyes, and they probably didn't have enough time to get eclipse glasses.

But me, I decided I was going to sneak outside, because this seemed really unfair. So right around the time of the maximum, I walked outside. And who did I see standing out there? All the science teachers. With their glasses, and their pinhole cameras, and their filtered little astrolabe telescopes. And they tried to get me to go back inside, and I said no.

So for any kids, I said, give me your glasses. It's only fair that we all get to have this experience. This is a solar eclipse for everybody-- partial, total, whichever you're going to get to see. It's hosted, we're hosting the shadow of the moon across the United States, a really exciting experience.

If you make it to totality, it will be magical. If you don't, and all you get, all you get, is this partial where you get to see the sun start to disappear-- you won't get the full disappearance, but it will get about 70% gone-- there is something wholly unnatural about that.

The sun is our life source. Watching it go away should be something we all want to try and look at. It won't happen that often in your lifetime that you could walk outside of your own house and watch even the partial happen.

So I encourage you, all of you, if you weren't planning on attending, attend. Get the proper eyewear. Don't stop your kids from going outside and looking at it. Just make sure you have proper either eclipse glasses, pinhole cameras, you can get tiny little filters for telescopes or binoculars if you have them.

For those interested in coming here, we will have a number of science educators here. We won't have a lot of astronomers here, unfortunately, because many of us are going to totality.

But we will have eclipse-viewing glasses. We will have a live feed of totality as it goes on across the United States. And we will have joyous, fun people. And also, we'll just have a radiant atmosphere for you to attend. So hopefully, that would draw all of you in.

Mentioning here for anybody that's from the press that this video we're releasing today for you, which will take you through a lot of the science. There's captions that will help your readers, or your online readers, or your digital readers, or however you have your readers, watch our video here.

And I'm going to turn it over to my colleague, Joe Rao, who's also going to take you through a number of slides on this total solar eclipse and partial solar eclipse. So Joe Rao.

[APPLAUSE]

JOE RAO (Hayden Planetarium Associate):

Thank you very much, Jackie. And good morning to all of you. Welcome again to the Hayden Planetarium. And I don't know about any of you, but for somebody like myself who has been interested in astronomy, and especially eclipses, since I was a very, very young boy, this upcoming week is going to be difficult for me to sleep.

And in fact, next Sunday night, for me, the night before the eclipse, it's going to be like Christmas Eve and New Year's Eve all rolled into one. It's going to be very difficult for me because I'm that excited. And I'm going to try to get some of you excited as well about what we're going to see.

Now should I hit this button here and forward it to-- there we go. So we have ourselves an eclipse. And Jackie mentioned the mechanics of the eclipse. The moon is going to pass between the sun and the Earth on that particular day, and cast a shadow. You notice, if you will, that the shadow is cone-shaped, and it gets to a point on to the Earth's surface.

In fact, this view that you see here was taken by the now-defunct Russian Mir space station back in 1999, when the Mir space station was passing over Europe, and there was a total eclipse of the sun taking place over Europe. That's what that black blotch is. That is where you want to be. That is the shadow of the moon, the umbral shadow of the moon, which, again, only narrows to a point.

In the case coming up next week, that shadow is going to taper off to a point about 70 miles wide. And that dark blotch will come in to the Oregon coast, and as Jackie mentioned, will go all the way across the country, exiting at South Carolina, Charleston, South Carolina, just 90 minutes later.

How many of you would like to take a plane flight from Salem, Oregon, to Charleston, South Carolina, and take only 90 minutes? That shadow's going to be moving at an average speed of about 1,600 miles per hour.

Now Jackie already did this with you, but I didn't get a good view. How many here in this audience right now have seen a total eclipse of the sun? OK, a few hands. Question-- are you sure? Really?

I've asked that question many times over the years of people. Have you ever seen a total eclipse? Here is Rao's litmus test as to whether or not you really did see a total eclipse. If, for example, you answered no, reality says, no, you didn't see a total eclipse.

Some people, when I ask that question, say, I think so. If you answer it that way, no, you didn't see a total eclipse of the sun. Others will ask, I'm pretty sure I did. No, you didn't see a total eclipse of the sun, I'm sorry, if you answer it that way.

How about this? Yeah. Yeah? Probably not, you didn't see one. Or, almost. Maybe some of you remember when you were younger, a lot younger, back in 1970, on a Saturday afternoon, there was a total eclipse of the sun that went right immediately adjacent to the Eastern Seaboard. And here in New York, we had 96% coverage, almost a total eclipse.

When I ask that question about, did you ever see a total eclipse? They say, almost, or, I did, but I-- no, you didn't see one. Probably not. But, but if I ask you, have you ever seen a total solar eclipse? And you say, oh my god! Let me tell you, we were there, and all of a sudden, it started getting dark, just like a theater when they dim the lights.

And all of a sudden, all of the birds go flying every which way. And up in the sky, all of a sudden, it looked like a glowing eyeball in the sky. And the stars came out. It's unbelievable. And in two minutes, it was all over. And it was the most amazing thing. I'll always remember that.

If you go that way, yeah. Yeah, then you did see a total eclipse of the sun. Because you see, ladies and gentlemen, a total solar eclipse is not just something that you see. A total eclipse of the sun is more than that. It's an experience. Every fiber of you gets involved during those few precious moments of totality.

This is a painting rendered of the January 24, 1925, eclipse by Howard Russell Butler. He did several eclipse paintings, and they're property of the American Museum of Natural History. And this is what the sun looked like on that particular morning here in New York City. A beautiful, beautiful sight indeed.

This is what people wait years and years to see-- a total eclipse of the sun. And again, the beautiful diamond ring effects that grace our skies, either just as totality is about to begin or just as totality comes to an end, they remain indelibly implanted into our memories, and they remain a lifetime once you have been there to see a total eclipse of the sun, sitting in the shadow of the moon.

Now how long have we been waiting? How long have scientists been waiting to see this eclipse? In August of 1932, there was a total eclipse of the sun that passed across the Northeastern United States. It went from Montreal, Canada, to Cape Cod. One of the foremost eclipse experts of that day, of that time, Samuel Alfred Mitchell, pointed out that this probably, that particular eclipse in 1932, would be the last good eclipse, logistically speaking, to get to until August 21, 2017.

Ladies and gentlemen, this is The New York Times from August 1932. That's the headline. It seems very strange and weird to see a day so close, just a week away, appearing in a newspaper 85 years ago. And here we are, all these years later, and it's almost here.

And here, you see the shadow moving across North America. That little dot that you see right in the middle of the shadow, that is the place that you want to be. Underneath that little dot is where a total eclipse is going to take place. And look at the size of that penumbral shadow. Everywhere within that big, circular shadow, we'll see at least a partial eclipse next week.

Here's another view of the total eclipse as it crosses the United States. And whereas we have here the path of totality-- that's the totality path, that's where you want to be-- on either side, we have the increments of the partial eclipse. For example, along this line, people will see 80% coverage, 60% coverage, 40%.

If any of you plan to be up in far northern Canada near the Arctic, 20% coverage up here. Greenland will get about 10%. Northern South America will see some of it. Even Africa and, at sunset, London, England, will see a part of the eclipse.

Interestingly, however, between this line and this line-- this darker shade right here-- there are 12 million people who live in the totality path. Between these two lines here and here, 220 million people are within a one day drive of totality.

And I can tell you, the Federal Department of Transportation has sent out advisories to all the states that are in the eclipse zone, advising them to be prepared for history-making traffic jams late Sunday night into eclipse day next Monday, as they expect a lot of people to try and get into the totality path to see the total eclipse.

It runs, again, from the coast of Oregon, where it will last two minutes, right here, from about Northwestern Missouri to eastern Tennessee. That's where the eclipse will last the longest-- 2 minutes and 40 seconds of darkness. So come by car, come by train, or you can even come by plane.

Alaska Airlines is going to fly an aircraft into the totality path about 1,000 miles to the west of the Oregon coast. And I had a hand in this, believe it or not. Last year, there was a total eclipse of the sun over Indonesia. Who wants to go to-- I mean, it's a lovely place to go to if you're interested in exotic places, Indonesia. I didn't feel like going.

But when I looked at the eclipse path last year, I noticed it was passing 700 miles north of Hawaii. Hawaii is a nice place to go, huh? And I wrote to the airline and said, hey, there's a flight that comes out of Anchorage, Alaska. And if you delay that flight and change the path a little bit, you might be able to get the folks on that aircraft to see a total eclipse of the sun.

It took about a half a year, but I finally did convince them. As my grandmother used to call me when I was very young, a scutch. I was a scutch to Alaska Airlines. So finally, they said, all right, we'll do it. And they did.

The people onboard a 737-900 aircraft, all 200 of us, got a chance to see the shadow of the moon, got a chance to see the solar corona, got a chance to see a thrill of a lifetime. They got such tremendous publicity afterward-- Good Morning America, Scott Pelley, Lester Holt, AP, UPI. The publicity for them was tremendous.

Well, out of the blue, this past May, I got a phone call from Alaska Airlines. Hey, we want to do that thing that we did last year with the eclipse. Would you be interested in going onboard with us and showing us how to do it again? And I said, well, you've got a problem. What's the problem?

Well, you see, if you try to fly a plane over the United States, the sun's going to be way, way up here, not like it was last year when it was down near the horizon. You can't see the eclipse if it's way, way up here unless you saw a hole in the top of the airplane. They didn't want to do that. So what we did was we decided we were going to go 1,000 miles to the west of Oregon, where the sun will be a lot lower.

And next Monday, if everything goes according to schedule, we will fly into the shadow of the moon-- myself, some avid, assiduous stargazers, and eclipse watchers, and the news media-- where we will be seeing a total eclipse of the sun, lasting all of 103 seconds. So much preparation for 103 seconds of darkness. OK, you can go now. Zoop.

Besides being an associate here at the Hayden Planetarium, I also work at Verizon FiOS1 News as their weatherman or their on-camera meteorologist. And you better believe I've been telling all of our viewers about the upcoming partial eclipse here in the New York area.

This, as Jackie mentioned, this is what we're going to see. It'll start at 1:23. The moon will begin moving in on the sun. There will be a little bit of a bite taken out of the sun. The maximum eclipse, about 3/4 of the sun will be covered. Next Monday, weather permitting, 2:44 PM, with the cusps, or horns of the crescent, pointing downward. That will be the peak of the eclipse here in New York. And then it will come to an end as the moon moves off the sun's face at 4 o'clock.

Question-- and people have asked me this a lot-- so you get this much at 2:44. What are we going to see here in New York? Are there going to be any kind of effects? And interestingly, doing a little bit of studying here, a very famous amateur astronomer by the name of Leslie Peltier, he discovered 12 comets.

He was the first to cite a couple of nova that appeared in the sky, exploding stars. And he lived in the early and mid 20th century. He lived in Delphos, Ohio. And in 1918, there was a partial eclipse over Delphos. And guess what? 3/4 of the sun was covered. It's exactly what we're going to see here next Monday.

And Mr. Peltier wrote in his log at the peak of the eclipse, "At mid eclipse, I turned away and looked about. Everything I saw, the nearby fields, the distant vistas, all seemed wrapped in some strange, unearthly, early twilight. The sky seemed darker, shadows sharp and distinct. A cool wind, almost chilly, had sprung up from the west."

So if we're lucky enough to have clear weather here in New York, at 2:44 next Monday afternoon, I have a feeling that pretty much is what we're going to see here from the New York metropolitan area. It's like, let me use another analogy, when you get a flashlight, and you put new batteries in the flashlight, the light glows what? Brilliant white.

But if you run the batteries down to about 30%, so you still have 70% of the energy, but 30% is down, you turn on the light. The light doesn't glow quite as bright. In fact, it looks almost yellowish in color. And that's kind of like what it's going to be next week at the midpoint of the eclipse. There's going to be a certain amount of yellowness in the air along with that dimming or diminishing of twilight for a few minutes around the peak.

Of course, we don't want to advise anybody to look directly at the sun, especially if you have a binocular or a telescope. You could wreck your eyes if that happens. People are saying the best way to watch it is on television. Although even here, sometimes, people get a little leery. You see the person with the bag over her head.

In the 1950s, there was a very famous TV show, a kid show, called Howdy Doody. How many of you remember Howdy Doody, right? Once, during the Howdy Doody show, there was a small partial eclipse of the sun. So NBC, who televised Howdy Doody, figured, hey, why don't we put a camera on top of the RCA building, put a filter over the camera, and we'll show the kids the eclipse? And they did just that.

But somebody who wrote a book, an extensive book, about the Howdy Doody show, the history of the Howdy Doody show, said, that was the one and only time his mother would not allow him to watch the Howdy Doody show because she was afraid that if he looked at the TV screen, he'd go blind, believe it or not.

Best way to look at it-- go to your local hardware store or a welding supply store and get a piece of welder's glass. Number 13 or number 14, that's the welder's glass to get, 13 or 14. If you get anything less than 13, that's too bright, dangerous. You get anything more than 14, too dim, not a very good view of the sun. So that's what you could use to look at the eclipse, is welder's glass.

And of course, these eclipse glasses have been flying off the shelves. They're all over. I've seen 7-Eleven offer this. I've seen Lowe's hardware stores offer them. There are millions, millions, that have been made up for this event.

Be careful, however, there are some cheap knock offs where the sun might appear too bright through them and dangerous to look at. Make sure that the eyewear has an ISO number and has been certified to be safe to look at.

And if you don't have a welder's glass, if you don't have eclipse glasses, then all you need is a tree. I have a feeling Central Park, if it's sunny next week, is going to be very popular place to be. Put a white sheet on the ground and let the sunlight shine through the spaces of the leaves.

Just like pinhole cameras, every single one of those little spaces will produce an exact image of the eclipse as it appears in the sky. On the side of your house, or on the floor, or on the sheet, you could do it that way. And let me tell you, also, if it's a little breezy that day, the shadows, the crescents will appear to twinkle, which makes for an even neater effect.

Lastly, I just want to say this-- social media, wonderful. Everybody out there has their iPhone. Everybody there carries their camera. But social media, sometimes, can be a detriment in producing news, fake news. And this is fake news, folks.

All over the internet-- the world is going to come to an end when the eclipse occurs next week. America's day of darkness. We're going to have the end of days. That's all over.

You don't believe me? Just go on the internet, google the eclipse next week. Google "eclipse," "end of world." you'll see this all over the place-- the end is near. How many times in your lifetime have we heard this?

Remember, about six years ago, there was some pastor who said, I did special calculations. The world is going to come to an end on a Saturday in May in 2011. You remember that. Some of the newspapers had fun with that, printing end of the world editions.

"Buy This Paper." I like the top here. "Mets play like there's no tomorrow." And look at the weather for that day. "Fire and brimstone, 76." So don't believe it. If you hear anybody say the world is going to come to an end, there's something dangerous going to happen with the eclipse, it ain't happening, folks.

But I do want to tell you this again-- this is one of the great moments, one of the great spectacles of nature. And I was talking with Dr. Tyson a while back, and we both agree-- this belongs on everybody's bucket list. You have to see a total eclipse of the sun before you die. It is one of the great spectacles of nature.

And all of these years, we have not had a total eclipse of the sun here in the United States since 1979. One or two generations have passed since the last one. And in the last 38 years, eclipses have happened over China, over Russia, over Australia, over South America, even, for goodness sake, over Easter Island, but not here in the United States. Finally, one is coming to us.

Now you have your chance to see one of the great spectacles, a total solar eclipse, next week. And I hope all of you get a chance-- partial will be interesting here in New York-- but I hope all of you get a chance to see this, because you will take it to your grave. It is one of the great spectacles that you'll ever see in your lifetime. And I thank you very, very much for listening.

[APPLAUSE]

TYSON: If I can ask Jackie and Joe to come back up on stage. Joe.

RAO: Thank you.

TYSON: So, Joe, you showed the Boston Prudential Center in your slide of the tri-state area. How did that get in there?

RAO: Unfortunately, I was not able to dig up, at the last minute, a view of the New York skyline.

TYSON: So it's A generic city.

RAO: It's a generic-type city. I'll tell you what, when I use the Boston Prudential Center, sometimes, it looks very much like White Plains.

TYSON: Oh, OK.

RAO: That works in Westchester.

[LAUGH]

TYSON: So let me ask a couple of questions here, and we'll go to the audience. So, Joe, some might ask, is the partially eclipsed sun more dangerous than at any other time to look at the sun, or is it just the general fact you shouldn't look at the sun no matter what's going on?

RAO: Absolutely. People think that when the eclipse is happening, that the sun is suddenly emitting some strange, dangerous rays that you're not supposed to be exposed to.

TYSON: Eclipse rays.

RAO: Eclipse rays. But that's not the case. The sun is dangerous to look at all the time. The problem is, normally, on a typical day, how many of you just stand out on a street corner and look up at the sun? No, you don't do that. And you know you don't look at the sun because it hurts if you look at the sun with bare eyes, so to speak.

But when they mention an eclipse in the newspaper, or on radio, or television, then all of a sudden, the curiosity factor goes up. And while this case, curiosity won't necessarily kill the cat, curiosity will, if you look at this the wrong way, could very well kill your eyesight. So you have to be very, very cautious as to how you do look at the partial phases of an eclipse.

TYSON: And one thing I like to emphasize-- Joe had spent just a few minutes on it-- maybe it's the luxury of seeing more than one total solar eclipse, but when you do have that luxury, then you can take time away from the eclipse and watch everything else that's going on around you-- the eclipse shadow coming, the images on the ground, the wind changes, the temperature changes. So is that something you would encourage people to do, even if it's their first time?

RAO: Yes, I would encourage you to. Because during a total eclipse-- if this is your first, and you're with a bunch of people, like we have here-- what usually happens is about a minute or two before totality, people start to murmur. And the murmur gets louder and louder. And people start yelling at each other, saying, this is amazing. Look what's happening, look what's happening.

And at the moment when we have totality, for the first 30 seconds or so, people start screaming their heads off. In fact, we had one guy on the plane last year who must have said, "oh my god," 36 times in the span of only about a minute or a minute and a half.

TYSON: I think I heard that recording.

RAO: Yeah.

TYSON: Yeah, yeah.

RAO: It's almost like a life-changing event. I'm not too much into religion, but you can understand when you see this, especially for the first time, why ancient people beat hard on the drums, shot rockets up toward the sun to try to chase away the dragon to release the sun. It is nothing like you have ever experienced in your entire lifetime.

And that's why I urge people to make the trip and travel to see a total eclipse. And as you just mentioned, Neil, to observe not just the sky, and the stars, and the sun coming out, and everything else, but also observe nature, because it's an amazing sight.

And please, please-- and I'll let you talk about this-- if you're going to see it for the first time, totality, don't stand outside with your iPhone and look at the eclipse like this. Please don't do that. Soak it up. Enjoy it.

If you want pictures, get somebody nearby to you to send you the pictures of the event. This is something to enjoy and take every single second in, because, again, every single second is precious during the short time that the eclipse is in totality.

TYSON: Jackie, one of the things that people notice, without understanding explicitly what's going on, is that shadows look different. They take on an eerie sense. That would surely happen even in New York City where we have 72% coverage. Could you comment on what's going on with the shadows?

FAHERTY: Well, during a partial eclipse, you have less of the sun that's coming. The sun is being eclipsed by part of the moon. So for those that get to come to totality, you'll see major differences in your shadows as you're essentially going to a twilight night sky as the event proceeds.

For those in New York, I would encourage you to examine your shadows, because they will also change because the light that you're getting from the sun is changing. You'll notice differences in your shadows on a cloudy day as well. So at any point during when the sun's light is changing, you would see differences in the kind of shadow that you cast on the ground.

TYSON: And I'll add just to Joe Rao's point, anyone below a certain age has to experience amazing phenomenon by looking at the video image on their smartphone as the smartphone takes in the actual image. I get it. You want to then look at it later.

But then you would not have experienced it in the moment with your own eyes, looking at the real event. And maybe just, like I said, put down your smartphone and experience this one emotionally, psychologically, physically, rather than just through the screen.

RAO: Absolutely.

FAHERTY: I, being the youngest on this stage, I think, don't leave your cell phone at home though. You can be there, and then I think this is going to be one of these things that shuts down Twitter, or Instagram, or social media after.

TYSON: It might not because it's at a different time across the country. That spreads out the load.

FAHERTY: So I think that it's going to be in your feed, and maybe, if you're not going to be at totality, you could watch totality happen over the 90 minutes by following it on social media.

TYSON: Yeah. So let's go to the press, if you have any questions based on what you've seen or even not. And just give me your name and what your outlet will be. Microphones will be coming to you.

QUESTION: Yeah, Ken Gale, WBAI FM. I wonder if you could elaborate on how animals and plants react to an eclipse. What should we be looking for?

FAHERTY: I can give my opinion, and Joe, who's actually been at a lot of solar eclipses, can say. I want to reiterate that the sun disappearing, as I mentioned, is wholly unnatural to occur. Even the human body will have a reaction to this, mentally, as you watch the sun disappear from the sky as the sky gets dark.

TYSON: Just to be clear-- unnatural not to mean that solar eclipses are not natural. They happen all the time. But in our life experience, it is sufficiently uncommon that you end up reacting in ways unfamiliar. I just want to clarify that.

FAHERTY: Thank you. Right. It is a natural occurrence to be occurring. However, how many times are you ever going to really get to see a total solar eclipse? Let your body feel it.

Animals certainly have the same and perhaps more raw reaction to it, because they don't actually have the context that we do that we know what's going to happen. So animals react to it, and the sun is gone. And you will see the animals react the way, maybe internally, you are reacting, which is wholly feeling like this shouldn't be happening.

TYSON: So typically, what goes on is they'll think the day is ending. So there are certain rituals that animals go through-- going to roost, returning home to their nests. You'll see this behavior as the sky darkens. And then it brightens up again, and they just freak out.

In Kruger Park in Southern Africa, there was a total solar eclipse that was right over-- do you remember this one? And there were all manner of animal behaviorists went to Kruger Park to observe what the rhinoceros and all the famous large mammals would be doing. But I didn't follow up on what they found. Did you know anything about that, Joe?

RAO: Yeah. The deer raced in panic. Various birds started twittering loudly just before totality, then they went silent.

TYSON: They were on Twitter? No, I'm just kidding.

RAO: Well, tweeted.

TYSON: Tweeting, Twitter, uh-huh.

RAO: So the shadow does have an impact. And even, for example, as it passes over the United States next week, in certain areas where, let's say, I live up in the country, up in Putnam County. And if you live in an area where the night critters start chattering right after sundown-- cho-choo, cho-choo. It's quite likely that's going to happen for the couple of minutes of totality. They're going to just say, hey, it got dark all of a sudden. They just react to that. They think that it's dark.

TYSON: Another question on the front row here. Wait for the mic. Your name and who you represent.

QUESTION: My name is Vicki Cobb. I write science books for children, and I'm a contributor to The Huffington Post.

TYSON: Excellent.

QUESTION: Just curious, what if there's cloud cover? What will we experience? How important is that?

RAO: Here in the New York metropolitan area, if there's a heavy cloud cover--

TYSON: He's a meteorologist speaking right now, so get ready to blame him if this doesn't work out. Go.

RAO: I'm hoping that it'll be clear next week. They think we will have at least some views of the sun. If it's a heavy cloud cover though, I don't think you're going to notice very much. If there's a cloud cover, and you happen to be in the zone of totality, however, even with the cloud cover, it's an amazing experience.

I was in Canada, my very first eclipse in 1972. It was like 98% of the sky was covered by clouds. We just happened to be lucky, and the corona shone through the remaining 2%.

But the rest of the cloud cover went from battleship gray to a saffron, salmon, iodine color. It was an amazing color. There were colors I didn't even know had a name. And it all happened during the two minutes or so of totality. And also, you got to see better the shadow of the moon, the front edge coming in.

It's like that soap opera that was on television many years ago, The Edge of Night. You see the edge of night going across the skyline. You actually do see the edge of the shadow on the clouds, rolling past you. You're in totality. And then the back edge of the sun moves by, and the sky brightens up.

So if you're in the total zone during the eclipse, and it happens to be cloudy, it's still something to see. You'll lose a lot because the main spectacle is under a clear sky. And here in New York, again, I don't think you'll be able to notice very much if we do have quite a bit of cloud cover, unfortunately.

TYSON: Yeah, so one of the challenges here is when the sun is half covered, so half the light is reaching you, that's not any different from if you had cloud cover. So when the clouds are up, and it's a little dark, you just think the clouds are a little thicker in that moment unless you already know what's going on.

I was privileged to read a diary of a migrating family in New England from the 1700s. And this was found in the attic of some-- well, it was the attic or the collection of someone who had just died-- From the family members. And they were reading, and it was handwritten notes. And they were on some kind of wagon train, whatever the counterpart is to that in New England.

And in there, there was an account. So apparently, it describes, "The sky began to darken. None of us knew why. And I decided to stop the wagon, tell everyone to get out, and get on their knees, and pray for forgiveness, because surely, the end was near. Our prayers were heard, because several minutes later, things were bright again."

Now in the 1700s, that's late enough that people understood eclipses. So if there was an actual total eclipse, they would have seen it. But I concluded, once I looked to find out which eclipse that was, because she had a sense of the date-- I found the exact eclipse track.

So we knew where the wagon was at the time. I had to conclude it must have been completely overcast, because otherwise, they would have known that it was an eclipse. And so it just got dark. But their prayers were answered because the sun came back.

RAO: Well, that's why the story about chasing away the dragon in China and Japan, because that was their legend or theory.

TYSON: The dragon was biting the sun.

RAO: Was biting into the sun. And guess what? Every time they shot a rocket off, or screamed and yelled, and beat the drums, the dragon always went away. So it always worked.

TYSON: Yeah, so keep doing it. Other questions. Yes. Front row.

QUESTION: Hi, my name's Tony Merevick, and I'm with Thrillist. My question is for all three of you. What is your strongest response to someone who may be on the fence about watching the eclipse on Monday? And similarly, what are your top three reasons, personally, for watching it, besides it's basically your job?

FAHERTY: I can go first on this. I've been thinking about this a lot. I actually have never seen a total. I've only seen partials in my life. And like Neil mentioned, or Joe mentioned, that they discussed, putting it on your bucket list should really be there.

In part, I say, I come to two different reasons. One is that, as it's happening, you get the opportunity to stand in the shadow of the moon. Now the last time we went to the moon was decades ago. And I can say with some definitiveness, I don't think I'm ever going to have the opportunity to go to the moon, this object that's out there most nights, depending on which phase it's in. And I'd like that connection to the moon.

So I don't just want to see partials. Partials are exciting. I want to stand in the darkest part of the moon as the closest connection I'm going to have to that object that's so important to the nighttime sky. As an astronomer, I think about the moon a lot.

And not just that. So standing in the shadow of the moon is one thing. But this idea, which Joe did a great job of emphasizing, and like I was trying to mention, this unnatural idea-- we've got a sun that is the source of where this planet came from. We formed around that sun. So the moon was a part of it. We're all a part of it.

And then on that day, we're going to watch it, if you're in totality, you watch you go away. As the human species which relies on it so much, that seems like such an enormous thing to watch. I want to feel that moment.

I want to know what that's like, to watch the thing that gave us life, the thing that is the reason that we're here, I want to watch it disappear. Maybe that's morbid, now that I say it like that, but I want to watch it disappear, and then I want to watch it come back.

Because it's also a wonderful affirmation of how astronomers are good at their jobs. We predicted when it was going to happen, and we gave you the times it was going to happen, and we've been doing this for some time now. And it happens. I want to be there for when it happens.

TYSON: Joe.

RAO: Well, as Jackie just mentioned, you look up at the moon at night, and you almost wish-- you want to touch it. It's so interesting. You've seen it all of our lives. A total eclipse of the sun is the one and only chance. Maybe you can't touch the moon, but the shadow is going to touch you.

The moon goes around the Earth at a speed of about 2,300 miles per hour, a tremendous speed when you think about it. And yet, here, that shadow is going to extend all the way down from the moon to the Earth. And for a few precious moments, that shadow's going to come racing right towards you, through you, and past you. And you will be experiencing it as a tangible sort of thing in the strangest way.

It's not like a sunset or sunrise. It's not like an approaching thunderstorm. It's just something different, something really, really awe-inspiring, to keep using a hackneyed phrase. And that's what I think about when I see a total eclipse. This, by the way, will be my 12th coming up.

TYSON: Show off.

[LAUGH]

RAO: I may be a meteorologist, but I'm not a storm chaser. Chasing eclipses is a lot safer than chasing a tornado. So that's my thing. And it never gets old. It never gets old. I get blown away every time it happens.

I went through a period from 2008 to 2015 without getting my fix. So in 2015, when I saw it after a seven-year interval, I'm looking at it, and I'm saying to myself, my god, I almost forgot how beautiful and spectacular this is. And the only way you're going to understand what I'm saying is if you see it yourself.

TYSON: I'll just say that when I think of the solar system, and the objects in orbit, and their appointed paths, I think of them as pirouetting dancers in a cosmic ballet, choreographed by the forces of gravity.

RAO: A pas de trois.

TYSON: It's what?

RAO: A pas de trois. I'm not French.

TYSON: Oh. And so knowing this, as an astrophysicist, to recognize that occasionally, things line up in ways that are uncommon or unusual, either in your life experience or for the Earth itself, to deny yourself of that opportunity would be to not live as full a life as you could have, experiencing the natural world around you.

So for those who raised their hand and said, we're not going to the eclipse, there is no excuse. There's nothing you can say to justify not going to the eclipse. I don't even want to hear what you-- just talk to the hand. There's nothing you can tell me.

We live in a day when everyone can travel. It's not like 400 years ago when nobody had a car, nobody had an airplane. Today, everyone has access to mobility. And so there is no excuse. Time for just a couple more questions. Yes.

QUESTION: I'll make it quick. Hi, I'm Elise Finch. I'm with WCBS Channel 2. So my question is this. For a lot of New Yorkers, some of them have certainly ignored the eclipse up until now. Now we're a week out. One of science's biggest stars is talking about it and saying there's no excuse to miss it.

So for the person, for the New Yorker who can't leave the city for a variety of reasons, they'll be here, tell me, what should they do? What is your personal checklist to them? If you wouldn't mind to speak directly to our viewers, what should they do to get ready for it? And then what should they do in those few, precious minutes?

TYSON: They should come to the American Museum of Natural History, where Jackie is running the program.

FAHERTY: I'm not going to be here. I'm going to be in Wyoming. However--

TYSON: Oh, you-- well, who's running the program?

FAHERTY: We have some awesome science educators that will be here, graduate students.

TYSON: You'll be in Wyoming?

FAHERTY: I'm going to be in Wyoming.

TYSON: You're skipping town?

FAHERTY: I am going to totality since I haven't been to totality yet. However, we will have here, as Neil's pushing on being here, we'll have eclipse glasses, we'll have science educators, we'll have streaming live here.

TYSON: Oh, for the person who can't come here. OK, here's what you do. I'm going to tell you something nobody else is going to tell you. You ready? If you can't come here, you can't go to totality, and you don't have eclipse classes, here's what you do.

Go into your kitchen and get a spaghetti strainer or colander. Not the mesh, the kind with holes in it. Go outside and hold that up over the ground. Each one of those holes will act as a pinhole camera, and you'll see hundreds of images of the crescent sun on the ground, and you can watch the eclipse unfold safely.

And I assume they eat and maybe have had spaghetti sometime in their life, so they'll have a spaghetti strainer for just this purpose. And that's the urban version of watching the pinhole camera images through the mottled light of sunlight passing through the leaves of a tree. It'll just be fun, just watching that happen. OK. Let's take one more question.

QUESTION: Hi, so I know that--

TYSON: You are from?

QUESTION: Oh, sorry. [INAUDIBLE] with space.com. So I know Jackie's going to be here. Joe Rao's going to be up in the sky somewhere. But, Neil, where are you going to be for the eclipse?

TYSON: I will be in a place that is not disclosed. I'm going to a media blackout during the eclipse. It's an event that can, and will, and is selling itself. So I am not necessary in support of it.

It will force local press and national press to dig deeper in their Rolodex and find professors at community colleges, heads of local planetarium clubs, and tons of thousands of people who have sufficient expertise to tell the media anything they want about this eclipse. And I will not be found. I will be in totality somewhere on Earth or above it, I assure you.

RAO: Actually, Alaska Airlines asked me to give an invitation to Neil to be onboard the flight. They were going to give him the best seat in the house on the plane. And Neil said, I'm blacking out on this with the media, Joe. I'm not going to be on that plane. Enjoy the eclipse at 38,000 feet, but I'm going to be somewhere else.

TYSON: Somewhere else.

RAO: Most people would have said, yeah, that'd be great to see an eclipse of the sun from the-- Neil, Neil's going to be where he's going to be.

TYSON: Yeah, I'm there for other events that maybe requires some extra interpretive efforts of an explainer. The eclipse doesn't require that. It might bring thousands of other people up into the media. I think we're overdue for that. So thank you all for coming.

Jackie and Joe will be available through this gentleman here, Roberto, for further one-on-ones. Thank you all for coming, the press, and for those who were just chilling, walking through the Hall of the Universe. We are signing off. Enjoy the eclipse next week, everyone of you. Take care.

[APPLAUSE]

RAO: Thank you.

[end of audio]