Jason Kendall's Introductory Astronomy Course

Adjunct faculty in Astronomy at CUNY Hunter (2015-2018) and William Paterson University (2011-2020)
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What is a Solar Eclipse?

In this video, I share my experience with the Total Solar eclipse of August 21, 2017. It was a special time for me for a lot of reasons. Watch this video to learn what you can see, and what to expect if you are in the path of totality for an eclipse. Also, I have a bunch of advice on how to watch the upcoming April 8, 2024 eclipse.

Lecture Notes for This Video

Module 1: Foundations of Observational Astronomy: The Moon, the Seasons, and Mapping the Sky

  1. Navigating the Night Sky
  2. Angular Measurements and the Celestial Sphere
  3. The Celestial Sphere
  4. What Causes the Seasons?
  5. Lunar Phases and Months
  6. Lunar Eclipses
  7. What is a Solar Eclipse?
  8. Watching the Total Solar Eclipse of August 21, 2017
  9. Cosmic Distances using Parallax
  10. How do we know that the Earth is Round?
  11. How Big are the Sun and Moon?
  12. Geocentrism is False

Video Transcript

00:00:00:00 - 00:00:24:14
Now let's take a look at some images that occurred during the August 21st, 2017 total solar eclipse that I went to in Glendo, Wyoming. We were all situated outside of a football field in in a small high school, and it took a long time to get there. And it was a big, big, big trip that was associated with a wonderful, wonderful travel agency that I worked with.

00:00:24:17 - 00:01:00:11
But I met a lot of nice people on the way. In any event, these images were taken by a person that I met there. Vishnu Reddy at this started off the first contact is what it is called when the when the disk of the moon starts to occult the sun that is called first contact and that is roughly at about four 1024 in the morning at the time at this at at Glendo, Wyoming, at the time, the sequence up to totality took about an hour and 22 minutes for the moon to move across the sun, which is really fascinating.

00:01:00:14 - 00:01:31:01
So let's see how long this took and watch the progression of images that occurred one after the other all the way up to totality. I paused it here because look at those things. They're called Bayley's beads and the beading is because the moon is not perfectly round. It has very tall mountains. So what we're looking at is sunlight that's coming through the between the mountains and those.

00:01:31:03 - 00:01:50:21
And that's why there's a little gap in there. And it's a little darker spots because there are tall mountains that are cutting off the sun as it's on the moon that are as it's as the passing in front. We also start to see this pinkish glow that I'll describe in a little bit later. And then we get closer and closer to totality.

00:01:50:28 - 00:02:25:07
And finally, here we are at totality at roughly 1142 in the in the morning, this presence of totality lasted about 2 minutes and 29 seconds. Only two and a half minutes of totality. So everybody was like staring at who are just amazing because you can see this in the sky. You will see the corona using sunglass, using the using, got using the special glasses, the glasses as per se, but just a filter.

00:02:25:11 - 00:02:48:05
A solar filter allows you to look straight at the sun. We you see off to the side at about almost 3:00, maybe 230 on the sun and 4:00 on the sun. Those little pinkish loops, those are prominences. Those prominences are huge loops of gas, of hydrogen gas. That's why the pink and I discussed this in the video on the Sun.

00:02:48:07 - 00:03:13:22
I those things are huge. By huge, I mean, each of those little tiny pink loops is much bigger than the entire planet Earth. But the more prominent thing you see is called the corona, which are these wispy gaseous elements that are being there streaming away from the sun. They're extraordinarily hot. The surface of the sun is about 6000 degrees kelvin, but the corona is millions of degrees kelvin.

00:03:13:24 - 00:03:38:03
And so they glow on by the heat. They're so incredibly hot that they glow mostly in x rays, but we see them invisible light as well as atomic transitions in the visible light regions. So these are this is a solar wind and these particles are being ejected from the sun at extraordinarily high speeds. And they invite you to go look at my video on the sun.

00:03:38:05 - 00:04:09:17
But what's really important in here is that we had 2 minutes and 29 seconds of totality in Glendo, Wyoming, And you do see this in the sky. This is a photograph, but you also see it in the sky and you can see it with those glasses. It's just an amazing view. So let's continue on. And then we get to this fascinating part where the sun is just coming up from behind the moon and we see more of the pink chromosphere of the sun.

00:04:09:17 - 00:04:35:15
We see more of that Paul prominence at about 230 or almost 3:00 on the sun. Start on the sun's face, and we're reducing the amount of the corona that we can see simply because the corona is very dim with respect to even the chromosphere. So as it came out from behind the moon, or more specifically as the moon passed further and quicker, it went on its merry way in its orbit.

00:04:35:18 - 00:04:57:09
The sun's now reappearing, so the sun keeps more appearing. More and more and more we see the beads again. And then finally there's the Bailey's beads again. On the other side of the moon, we see that there is one tall mountain in there that's blocking it completely. But then we are still able to see the corona, the chromosphere, the pink chromosphere.

00:04:57:16 - 00:05:30:20
And this is a great image because you have the the chromosphere and the growing photosphere of the sun, which is the bright spot that would be the photosphere of the sun. But we're still able to catch just a bit of the other chromosphere in the same image, which is an amazing image actually. So this is right after 1145 in the morning and by 1:00 in the afternoon, 110 109 in the afternoon, the moon will have passed completely across the face of the sun, ending the entire eclipse event.

00:05:30:23 - 00:05:48:29
It was an amazing event. There is no question I would do it again and then planning to do it again for the April the 2024 one. And I'm going to try to do them again later in the coming decades and go to other countries. It's just an amazing experience. And if you do not get the chance to see a total solar eclipse in your lifetime, you've missed out.

00:05:49:04 - 00:06:07:20
It's an amazing experience and you should really try to get in the path of totality, not just see a partial get in the path of totality. It's a very narrow band, but you've got to try to do it. It might cost you a bit. It's going to be very expensive and it's only happened last for like a couple of minutes.

00:06:07:22 - 00:06:32:01
But it's an astonishing feeling that you get. There's this primal sense and I'll show you why in a second. Vishnu Reddy collected this data and this is a fascinating set of data. It shows the temperature of the air, the temperature really does drop a drop almost 25 degrees between the first contact and during totality, which is those two orange bars in the middle.

00:06:32:01 - 00:06:50:02
That's totality. And of course, it takes a moment for the atmosphere to catch up. But yeah, it dropped in temperature and you could feel it. You did want to put on a coat as time went on. I did want to put on a sweater, but nobody dared do that because it was it was going to last for such a short period of time.

00:06:50:02 - 00:07:17:29
You didn't want to miss any of the action that was happening, but it was amazing to actually see the two feel the temperature difference. So what did it look like at Glendon, Wyoming, during totality in the path of totality? This picture, again also by Vishnu Reddy, was is about halfway to totality. And we see that it actually does kind of look at giver the grass has a different hue to it as well as you start to see a purplish hue to the sky.

00:07:17:29 - 00:07:38:19
And that is true. You do start to see that dimmer thing. It's like you have a sunset, but the sunset is in the sky. That's what it feels like. And it's very strange. You have a sunset happening in the sky. It's the only way to describe it and it's very strange. Birds start to go to sleep. They really do.

00:07:38:19 - 00:08:03:27
They think it's sunset. It's amazing what happens during totality. Let me just show you a series of images that go from that moment, not halfway through totality, all the way through totality. And here it is totality. This is what it looks like in totality. You're in full darkness. You're in the shadow of the sun and you're ringed by a sunset.

00:08:03:29 - 00:08:24:27
Eerie, strange. The sunset is all around you in every direction because you're in the middle of a shadow. And yeah, you do see, I believe that's Planet Venus up there. That's what that white dot is. That's not a marker on the image. That's Venus in the sky. You do see that stars come out. You can see stars. It's absolutely amazing.

00:08:24:29 - 00:08:48:01
And it was an incredibly special time for me for another reason. My parents are seated here, so I'm off to the left and my mother is in the middle and my father's to the right and he's got a balloon in the background. It was great. These balloonists were trying to trying to keep up with the shadows. Wonderful to watch them scoot across the horizon as they tried to race the shadow.

00:08:48:03 - 00:09:13:05
I do not know how they did that, but they were having a great time. And this was an amazing thing because my my father did pass away in 2021. So he passed away four years later. And this was such an amazing opportunity for me to be able to take them on this on this tour of Wyoming and Colorado.

00:09:13:08 - 00:09:41:11
My father had been the the president of Power of Northwest Community College in Powell, Wyoming. So Glencoe was familiar territory to him. And he was a man of the Southwest. He grew up in Arizona and he loved you. He loved all that stuff. So the desert southwest is part of the family. And I was out there also doing covering the eclipse for W NYC and 1010 winds and AM New York.

00:09:41:13 - 00:10:04:04
I gave a live broadcast a couple of interviews with Salon. It was just an amazing time. I was trying to give a live broadcast to 1010 Winds radio. Right During that my intention was to be able to broadcast what it was like inside of totality, but unfortunately it was just so sad. My battery ran out like 10 minutes before totality.

00:10:04:04 - 00:10:43:09
So there I was just standing, enjoying it for myself and not giving it to viewers. But it was an amazing, amazing time. I had a wonderful time with that and it was completely special to be able to to be able to take my parents with me. And it was it was great. Besides, this for them was also wonderful as well, because part of the tour that I just described as the beginning of this was that it went through Trail Ridge Road in Estes Park, Colorado, and the last time they'd been on that road, they were driving from Boston to Los Angeles in 1955.

00:10:43:11 - 00:11:08:03
He was 20 and she was 18. And can you tell can you tell there was a there's a bit of a wonderful memory that's going on there. It was it was incredibly special to be able to take that with me on this wonderful, wonderful tour. Well, after it was all done, we tried to get home from Glencoe back to Cheyenne to our to our to our hotel.

00:11:08:06 - 00:11:32:16
And this happened. There were so many cars that it took hours to get back. I think it took we stayed at the football field until totality was complete, and I think we packed up pretty quickly. I seem to remember we kind of got on the road about 130 or so and the bus driver really wanted to get us going, but we didn't get back to the hotel till 6 p.m. or seven.

00:11:32:20 - 00:11:55:20
It took a long time and there were a couple of people that thought they'd be funny and ride on the grass to go south and get off the highway. But state troopers weren't having any of that and I got people back on the road. I was really surprised they didn't close that other the the northbound road over there and get people off these highways as fast as possible.

00:11:55:23 - 00:12:26:04
But there weren't any incidents of of note. There was that guy who who did run out of it who whose radiator did overheat and there was a really big problem in Wyoming with gasoline. And they ran out of gas, I believe, and saw a lot of gas stations across Wyoming. So when you do go to see a total solar eclipse anywhere, you have to be prepared for running out of gas in your car because everybody and their cat, their dog, their hamster is going to go and they will use up all the gasoline there.

00:12:26:04 - 00:12:50:26
So perhaps an electric car with a solar panel would be a really good idea with this time. So do be prepared for anything if you do go to a total solar eclipse. And so that was an amazing view. And here again is the the corona around the sun during totality. That two and a half minutes of totality on August 21st, 2017.

00:12:50:28 - 00:13:18:03
Now, you really should mark your calendar for Monday, April 8th of 2024. The path stretches from Mexico to Canada. Where shall you plan your rendezvous with the moon's shadow? And a lot of the eclipse aficionados go where the weather prospects are the best. And as you can see in this, the best weather prospects are from Dallas Fort Worth down through Mexico.

00:13:18:05 - 00:13:37:26
Wherever it's red on this image, that's probably going to be cloudy because the median cloud fraction is a measurement of how cloudy it is over a large period of time. I forget how meteorological it's typically this is, I think they usually do a measurement of a hundred years or something and kind of skew the most recent to being heavier.

00:13:37:29 - 00:14:11:20
But anyway, the median cloud fraction tells you whether or not it's probably going to be cloudy there. So it's probably going to be cloudy anywhere north of Memphis. So I, I would strongly suggest getting down to Dallas, Fort Worth, Austin and San Antonio and Nuevo Laredo. However, I happen to know that at this time, which is November of 2023, all hotels in Dallas, Fort Worth, Austin and San Antonio and surrounding areas have already been booked.

00:14:11:22 - 00:14:39:24
A buddy of mine said he could only find thing through a timeshare and through Airbnb. So that's amazing. Luckily, I have a friend in Mexico, so I'm probably going to be going down to Mexico during that time. So we'll see how that flies and I'm going to give an update in the future. But if you can get down to Texas now, if you do get over to the Rio Grande north of Nuevo Laredo, just know that that is really empty place.

00:14:39:24 - 00:15:09:02
And there's almost no gas stations in that area. Those roads are empty. There's very few facilities. And it's it's rugged terrain and it's hot and it can get extreme hot even in April. Be really careful if you choose to try to get in the path close to the Rio Grande in Texas. And if it's smart just to try to stay in Austin or San Antonio, that will probably be your best, best, best bet in the United States in that area than the most facilities, because you're not going to get a hotel at this time.

00:15:09:06 - 00:15:32:01
You might have to get a hotel up maybe 50 to 100 miles outside of the path of totality and then get up extremely early and try to drive there maybe 6 to 7 hours prior to totality. If you do not drive and get on the road up to six, maybe 12 hours before you won't get into the path of totality in Texas.

00:15:32:07 - 00:15:57:06
Texas has an extremely extensive road system, but it's mostly two laners away from the path of totality up there. And that highway that goes through in a wave over Laredo will eventually curve north through Marfa and go up north of the Big Bend. If you wish to try to go, say, 250 miles east of El Paso, there is a small sort of place called Fort Stockton, Texas.

00:15:57:06 - 00:16:23:25
I drove through. They've got a number of a number of really good motels. So if you fly into, say, Albuquerque or El Paso and then drive and stay the nights over in Fort Stockton, it's approximately from Fort Stockton to where you see in Nuevo Laredo, maybe a 4 to 5 hour drive. That's a long drive. I've driven from Matamoros or Brownsville, Texas, right down there, which is in the southernmost tip all the way to El Paso.

00:16:23:27 - 00:16:45:21
And that will take about 14 hours to drive that. And I've done that all in one sitting too long. Drive travels 900 miles from Matamoros for Brownsville, which is on the Texas side of of of the Rio Grande right there up to El Paso is not is 840 miles directly 860 an additional 40 miles goes to Las Cruces, New Mexico, which is where I went to grad school.

00:16:45:23 - 00:17:11:01
And my parents at the time were living in Brownsville, Texas, is automotive, so I've driven that area many times. I strongly advise that you try to eat your base yourself out of Austin or San Antonio or base yourself east or I'm sorry, west of that. And Fort Stockton would probably be a good chance. But you're going to be driving 302 miles or maybe 400 miles just to get to some place in the path of totality.

00:17:11:03 - 00:17:25:22
But it might be easier coming from the west into it than from the east. All right. So there's something if you do it, you will not regret it. But you must plan you must plan very far in advance.