WEBVTT 00:00:15.000 --> 00:00:47.000 music 00:00:47.000 --> 00:00:52.000 Good afternoon. I want to welcome you to a plenary session. 00:00:52.000 --> 00:00:57.000 It's our first attempt to have a presidential plenary. My name is Rex Fuller, president here at Western Oregon University. 00:00:57.000 --> 00:00:63.000 So what's very cool about today's plenary is it's around the eclipse which is coming up. 00:01:03.000 --> 00:01:07.000 For me it really blends three of our pillars out of our planning process together. 00:01:07.000 --> 00:01:12.000 Student success which I've talked about, academic excellence, but also community engagement. 00:01:12.000 --> 00:01:17.000 Because it's an opportunity for the university to host guests from all over the country. 00:01:17.000 --> 00:01:19.000 We have literally filled out all of our residence halls. 00:01:19.000 --> 00:01:24.000 We're down to about 70 beds that haven't been rented. Otherwise the campus will be really bustling. 00:01:24.000 --> 00:01:29.000 So as we look to August 19th and 20th and then the eclipse on the 21st 00:01:29.000 --> 00:01:35.000 We're going to have hundreds and hundreds of people here on campus trying to enjoy that opportunity 00:01:35.000 --> 00:01:37.000 once in a lifetime in some cases. 00:01:37.000 --> 00:01:40.000 But as you know we are really ground zero for the eclipse path. 00:01:40.000 --> 00:01:45.000 Which makes it all the more important for us to host something like this 00:01:45.000 --> 00:01:51.000 as part of our academic showcase in advance of what we're doing this summer and I hope many of you will be here this summer. 00:01:51.000 --> 00:01:56.000 It's not quite like the Olympics where you rent out your house and leave town. 00:01:56.000 --> 00:01:60.000 But I think we'll have a full slate of guests throughout the region. 00:02:00.000 --> 00:02:02.000 And so we're looking forward to that as well. 00:02:02.000 --> 00:02:10.000 But without further ado this plenary is about all of the different ideas around the eclipse from humanities to science. 00:02:10.000 --> 00:02:15.000 It gives you a sense of what it means in terms of religion in terms of people's beliefs. 00:02:15.000 --> 00:02:20.000 And it also is a chance to understand why does it happen how does happen 00:02:20.000 --> 00:02:27.000 and the mathematics behind some of the trajectories and also the science behind the work itself. 00:02:27.000 --> 00:02:29.000 So with that and without further ado, again welcome. 00:02:29.000 --> 00:02:39.000 music 00:02:39.000 --> 00:02:45.000 I have been interested in this eclipse specifically for as long as I knew what astronomy was. 00:02:45.000 --> 00:02:49.000 I have loved the stars for as long as I can remember. 00:02:49.000 --> 00:02:55.000 And I made a promise when I was a little girl that I would road-trip to wherever this eclipse was taking place and I would be there. 00:02:55.000 --> 00:02:61.000 And now I'm living right at the heart of it so nice at my child self. 00:03:01.000 --> 00:03:06.000 And so this poem was really inspired by that desire to see this eclipse. 00:03:06.000 --> 00:03:12.000 Not only for this rare occurrence because it really is a once in a lifetime opportunity. 00:03:12.000 --> 00:03:16.000 But when you see this eclipse it's a moment of connection 00:03:16.000 --> 00:03:19.000 not just for everyone that you're watching it with 00:03:19.000 --> 00:03:24.000 but in that moment you're watching something that people have been watching and wondering about 00:03:24.000 --> 00:03:31.000 for thousands and thousands of years for as long as we've been people which is spectacular if I do say so myself. 00:03:31.000 --> 00:03:36.000 So I'm really excited to share this with you all today. It's called Total Solar Eclipse. 00:04:38.000 --> 00:04:40.000 Thank you very much. 00:04:40.000 --> 00:04:42.000 applause 00:04:42.000 --> 00:04:52.000 music 00:04:52.000 --> 00:04:55.000 I'm so excited to be presenting the keynote presentation 00:04:55.000 --> 00:04:60.000 of the first ever presidential plenary at Academic Excellence Showcase. 00:05:00.000 --> 00:05:02.000 No pressure, right? 00:05:02.000 --> 00:05:06.000 I am here today to share with you some information 00:05:06.000 --> 00:05:12.000 about the Great American Eclipse we will experience here in Oregon on August 21st of this year. 00:05:12.000 --> 00:05:15.000 Now I am a professor in the earth science department here. 00:05:15.000 --> 00:05:18.000 And that means I like to share science as a good story. 00:05:18.000 --> 00:05:21.000 But my focus is in GIS. 00:05:21.000 --> 00:05:28.000 Which means I spend a lot of time thinking about, talking about, making and teaching about maps. 00:05:28.000 --> 00:05:33.000 So we are going to start this eclipse story with some maps. 00:05:33.000 --> 00:05:36.000 First let's find ourselves. 00:05:36.000 --> 00:05:41.000 Here is a map that shows Western Oregon University and the towns of Monmouth and Independence. 00:05:41.000 --> 00:05:47.000 And just south of town about two and half miles south of us here on campus is an orange line. 00:05:47.000 --> 00:05:51.000 That line marks the center of the path the eclipse will take this summer. 00:05:51.000 --> 00:05:57.000 And everywhere you see in this picture is in exactly the right place to see this eclipse. 00:05:57.000 --> 00:05:65.000 Everywhere in this picture will experience about two minutes of darkness around 10:19 AM the morning of August 21st. 00:06:05.000 --> 00:06:09.000 I have never personally experienced an eclipse like this before. 00:06:09.000 --> 00:06:12.000 But I am told that when the eclipse happens 00:06:12.000 --> 00:06:15.000 it will be like twilight just before those two minutes of darkness. 00:06:15.000 --> 00:06:21.000 Animals may act like it is nighttime. The temperature will drop noticeably. 00:06:21.000 --> 00:06:29.000 And the stars will come out and be visible even though it is still midmorning. It should be quite a show. 00:06:29.000 --> 00:06:34.000 So let's zoom out a bit and see who else in Oregon will get to see this show. 00:06:34.000 --> 00:06:40.000 This map shows the path of the eclipse which will start near Depot Bay, Oregon on our coast 00:06:40.000 --> 00:06:46.000 and will travel quickly from west to east before leaving the state near Ontario, Oregon. 00:06:46.000 --> 00:06:50.000 You may notice that the path on this map does not cover the entire state. 00:06:50.000 --> 00:06:54.000 In fact the path is only about 70 miles wide 00:06:54.000 --> 00:06:62.000 and areas outside of that shadowed band cutting across the state will not experience the total darkness that I just described. 00:07:02.000 --> 00:07:07.000 The eclipse will happen differently in Portland, Roseburg, Bend, 00:07:07.000 --> 00:07:09.000 anywhere outside of that shadowed path. 00:07:09.000 --> 00:07:17.000 If we zoom out still further we can see why this eclipse is being called the Great American Eclipse. 00:07:17.000 --> 00:07:22.000 The path for this particular eclipse starts on our west coast and ends on our east coast 00:07:22.000 --> 00:07:27.000 cutting across the United States from sea to shining sea. 00:07:27.000 --> 00:07:32.000 Again anywhere along this shadowed path will experience the darkness I described earlier. 00:07:32.000 --> 00:07:36.000 And everywhere outside of this path will see something different. 00:07:36.000 --> 00:07:43.000 While everyone in the continental US will see something strange happening with our sun on August 21st 00:07:43.000 --> 00:07:48.000 only those along that narrow path get to experience total darkness during the day. 00:07:48.000 --> 00:07:57.000 Hopefully it's starting to seem pretty special that we are only 2.7 miles away from the center line of that path. 00:07:57.000 --> 00:07:60.000 To describe what the rest of the US gets to see that morning 00:08:00.000 --> 00:08:06.000 we need to talk about what exactly a solar eclipse is and the different types of solar eclipse. 00:08:06.000 --> 00:08:12.000 A solar eclipse happens when the shadow of the moon falls onto the earth. 00:08:12.000 --> 00:08:17.000 This can only happen when the moon comes between the earth and the sun. 00:08:17.000 --> 00:08:20.000 The shadow has two parts. 00:08:20.000 --> 00:08:22.000 The umbra and the penumbra. 00:08:22.000 --> 00:08:25.000 The umbra is the darkest part of the shadow. 00:08:25.000 --> 00:08:29.000 And when it falls on Earth it covers a very small area. 00:08:29.000 --> 00:08:33.000 The penumbra covers more area but it is not completely dark. 00:08:33.000 --> 00:08:37.000 Because some of the light from the sun is not blocked in those areas. 00:08:37.000 --> 00:08:42.000 So a solar eclipse happens when some part of the moon's shadow falls onto Earth. 00:08:42.000 --> 00:08:48.000 There are three main types of solar eclipse. Total, annular, and partial. 00:08:48.000 --> 00:08:53.000 In a total solar eclipse the moon and the sun line up perfectly in the sky. 00:08:53.000 --> 00:08:61.000 With the moon completely blocking the light from the sun for a brief period of time. About two minutes for us here in Oregon. 00:09:01.000 --> 00:09:08.000 This type of eclipse can only be seen if you are in the path of the umbra the darkest part of the moon's shadow. 00:09:08.000 --> 00:09:14.000 This is referred to as the path of totality and it's that shadowed band we saw on the previous maps. 00:09:14.000 --> 00:09:21.000 During that time we experience darkness and we can see the corona of the sun and the stars all around. 00:09:21.000 --> 00:09:25.000 The corona of the sun is the outermost atmosphere 00:09:25.000 --> 00:09:30.000 and it is usually too dim to see compared to the full brightness of the main body of the sun. 00:09:30.000 --> 00:09:35.000 It's always there we just can't see it until a total solar eclipse. 00:09:35.000 --> 00:09:41.000 In a partial solar eclipse the moon never lines up completely perfectly with the sun. 00:09:41.000 --> 00:09:46.000 So only part of the sun gets covered and it winds up looking a little bit like pac-man. 00:09:46.000 --> 00:09:53.000 While the light will seem odd and dim if you're in the path of the penumbra it won't go away completely. 00:09:53.000 --> 00:09:60.000 That's because in the case of a partial solar eclipse the light from the sun is still making it into part of that area. 00:10:00.000 --> 00:10:05.000 And this also means you can't see the corona or the stars. There's still just too much light from the sun. 00:10:05.000 --> 00:10:10.000 A partial solar eclipse is what most of the US will experience this summer. 00:10:10.000 --> 00:10:15.000 This picture was taken during a partial eclipse in Texas in 2015. 00:10:15.000 --> 00:10:22.000 So if you're in Portland this summer this is the type of eclipse you can expect to see. The best show will be here. 00:10:22.000 --> 00:10:26.000 To explain the third type of eclipse an annular solar eclipse 00:10:26.000 --> 00:10:30.000 we need to look at more than just the shadow. 00:10:30.000 --> 00:10:33.000 We need to look at the mechanics of why eclipses happen in the first place. 00:10:33.000 --> 00:10:41.000 If we look at how our earth, our moon, and the sun are related to each other in space then we can draw a picture like this one. 00:10:41.000 --> 00:10:49.000 Here the earth and the sun very much not to scale are on a flat surface or a plane. 00:10:49.000 --> 00:10:54.000 As the earth rotates around the sun it stays on that plane. 00:10:54.000 --> 00:10:60.000 The moon is tilted about five degrees off that sun-earth plane. 00:11:00.000 --> 00:11:06.000 This means that it spends about half of its time above the plane and about half of its time below the plane. 00:11:06.000 --> 00:11:11.000 A solar eclipse can only happen when the moon crosses this plane. 00:11:11.000 --> 00:11:16.000 And only if the moon crosses the plane during a new moon. 00:11:16.000 --> 00:11:24.000 It's during a new moon that the moon is in between the earth and the sun which allows the moon's shadow to fall onto the earth. 00:11:24.000 --> 00:11:27.000 This typically happens about twice a year. 00:11:27.000 --> 00:11:35.000 The rest of the time we don't have an eclipse because the shadow is either just above or just below the earth. 00:11:35.000 --> 00:11:40.000 The tilt of the moon's orbit helps explain why we don't see a solar eclipse every month. 00:11:40.000 --> 00:11:42.000 But we still haven't explained annular eclipses. 00:11:42.000 --> 00:11:48.000 It turns out the moon does not always stay a constant distance from Earth. 00:11:48.000 --> 00:11:53.000 As it orbits it sometimes is a little bit closer and sometimes a little bit further away. 00:11:53.000 --> 00:11:59.000 It wobbles in its orbit which is why I titled this talk Bamboleo. 00:11:59.000 --> 00:11:65.000 Bamboleo is Spanish for wobble and the name of a rather catchy song we heard the beginning of earlier here. 00:12:05.000 --> 00:12:10.000 This song is about two people who wobble into each other's lives and back out again. 00:12:10.000 --> 00:12:14.000 Just like the couple in the song it is the wobble of the moon's orbit 00:12:14.000 --> 00:12:21.000 both above and below the ecliptic plane and further and closer to earth that gives us the three types of solar eclipse. 00:12:21.000 --> 00:12:26.000 So if an eclipse happens when the moon is further away from Earth 00:12:26.000 --> 00:12:32.000 then it no longer actually appears large enough in our sky to completely block all of the sun. 00:12:32.000 --> 00:12:37.000 When this happens a small ring of the sun is still visible all the way around the moon. 00:12:37.000 --> 00:12:40.000 This is an annular solar eclipse. 00:12:40.000 --> 00:12:43.000 Now that we know about the three types of solar eclipse 00:12:43.000 --> 00:12:48.000 it might be a good time to talk about the difference between a solar eclipse and a lunar eclipse. 00:12:48.000 --> 00:12:52.000 In a solar eclipse the shadow of the moon falls on the earth. 00:12:52.000 --> 00:12:57.000 In a lunar eclipse the shadow of the earth falls on the moon. 00:12:57.000 --> 00:12:61.000 This means that lunar eclipses always happen during the full moon 00:13:01.000 --> 00:13:05.000 because that is when the moon is opposite of the earth from the sun. 00:13:05.000 --> 00:13:08.000 The earth's shadow has an umbra and a penumbra just like the moon's. 00:13:08.000 --> 00:13:14.000 Bu there's something different about Earth's umbra. Do you see the red wiggly lines? 00:13:14.000 --> 00:13:17.000 Even though the umbra is the darkest part of the shadow 00:13:17.000 --> 00:13:21.000 in the case of the earth's umbra not all of the light from the sun is blocked 00:13:21.000 --> 00:13:28.000 Our atmosphere scatters all but the longest wavelengths of light. That is to say all but the red light. 00:13:28.000 --> 00:13:35.000 So while most of the light is blocked, a small amount of red light still makes it through to shine on the moon. 00:13:35.000 --> 00:13:42.000 This is why during a lunar eclipse the moon appears dim and red as the shadow of the earth falls upon it. 00:13:42.000 --> 00:13:46.000 The shadow of the earth allows only red light to pass through the atmosphere and onto the moon. 00:13:46.000 --> 00:13:51.000 This picture was taken during a total lunar eclipse in Egypt. 00:13:51.000 --> 00:13:55.000 And the photographer set up the camera to take regular pictures as the moon progressed through the sky. 00:13:55.000 --> 00:13:60.000 And the shadow fell onto and came off of the moon. 00:14:00.000 --> 00:14:06.000 Now we've heard a few times already that total solar eclipses are once in a lifetime events. 00:14:06.000 --> 00:14:09.000 I've said as much in the abstract for this talk. 00:14:09.000 --> 00:14:15.000 But I just told you a few minutes ago that solar eclipses can happen about twice a year. How can both be true? 00:14:15.000 --> 00:14:18.000 Well even though eclipses happen about twice a year 00:14:18.000 --> 00:14:23.000 the path of each eclipse is quite different nearly every time. 00:14:23.000 --> 00:14:28.000 It usually takes a long time before another total eclipse will cross over the same part of the earth again. 00:14:28.000 --> 00:14:33.000 So even though eclipses happen roughly twice a year, for any given spot on Earth 00:14:33.000 --> 00:14:37.000 they typically happen once in a lifetime or even less often. 00:14:37.000 --> 00:14:41.000 The last eclipse in Oregon was nearly 40 years ago in 1979. 00:14:41.000 --> 00:14:45.000 Which is admittedly less than the current average human lifetime. 00:14:45.000 --> 00:14:51.000 The path of totality for that eclipse was slightly north of here and at a different angle. 00:14:51.000 --> 00:14:57.000 Meaning that in 1979 both Monmouth and Portland, Oregon experienced a total solar eclipse. 00:14:57.000 --> 00:14:61.000 In 1918 there was a different path still. 00:15:01.000 --> 00:15:07.000 This path missed Monmouth and Portland so we'd have seen a partial solar eclipse. 00:15:07.000 --> 00:15:10.000 But this path did go through Baker City, Oregon. 00:15:10.000 --> 00:15:15.000 A painter named Howard Russell Butler went to Baker City, Oregon to witness the eclipse 00:15:15.000 --> 00:15:19.000 and painted this picture of the corona after that event. 00:15:19.000 --> 00:15:27.000 If we take all of the paths of solar eclipses in North America from 2001 to 2050 so looking at a 50 year time window 00:15:27.000 --> 00:15:32.000 and put them all on the same map we get a map like this one. 00:15:32.000 --> 00:15:37.000 The yellow paths on this map are total solar eclipses like we'll see this summer. 00:15:37.000 --> 00:15:43.000 And the orange paths are annular solar eclipses. That's when the moon's a little bit too far away. 00:15:43.000 --> 00:15:50.000 The next eclipse in Oregon after this summer will be in October of 2023 and that will be an annular eclipse. 00:15:50.000 --> 00:15:55.000 The next total solar eclipse in Oregon won't be until 2108. 00:15:55.000 --> 00:15:59.000 Though that particular event will only touch a tiny portion of the coast. 00:15:59.000 --> 00:15:66.000 Portland will not get to experience another total solar eclipse until July of 2169. 00:16:06.000 --> 00:16:12.000 So while the total solar eclipses in 1979 and 2017 are pretty close together in time 00:16:12.000 --> 00:16:17.000 we will definitely have to wait more than 100 years for the next one. 00:16:17.000 --> 00:16:22.000 So let's talk more about the details of the Great American Eclipse happening this summer. 00:16:22.000 --> 00:16:28.000 First if you are interested in watching the eclipse you need to think about eye safety. 00:16:28.000 --> 00:16:35.000 It is not safe to stare directly at the sun at any time the main body of the sun is visible. 00:16:35.000 --> 00:16:38.000 This mean on a regular day like today 00:16:38.000 --> 00:16:43.000 or even during the beginning or end of an eclipse when part of the disc is still uncovered. 00:16:43.000 --> 00:16:48.000 The only way to look safely at the sun is to get some protective eyewear. 00:16:48.000 --> 00:16:54.000 These wonderful images are from the eclipse in Oregon in 1979. 00:16:54.000 --> 00:16:58.000 We have some more modern versions available today. 00:16:58.000 --> 00:16:62.000 The key to eclipse glasses is that they have a very dark filter on them. 00:17:02.000 --> 00:17:05.000 We can probably pass these around if people want to see. 00:17:05.000 --> 00:17:10.000 But they block out the most harmful rays of the sunlight and help protect your eye. 00:17:10.000 --> 00:17:16.000 If you are interested in getting some we have WOU branded ones that will be available on campus this summer. 00:17:16.000 --> 00:17:19.000 The cities of Monmouth and Independence have also ordered theirs. 00:17:19.000 --> 00:17:26.000 Or you can check Amazon and you can get the fancier plastic kind. They were 20 bucks when I looked. The price is probably going up. 00:17:26.000 --> 00:17:30.000 Alright. So eclipse glasses, very important. 00:17:30.000 --> 00:17:36.000 If you do look online to purchase your own glasses make sure that they are ISO certified. 00:17:36.000 --> 00:17:41.000 So you sill see that on the glasses themselves or in the description for the glasses. 00:17:41.000 --> 00:17:45.000 And no, regular sunglasses will not cut it. 00:17:45.000 --> 00:17:48.000 Because they don't block out the important light. 00:17:48.000 --> 00:17:52.000 You definitely want to wear your glasses because here's the thing 00:17:52.000 --> 00:17:59.000 if you don't and you do stare at the sun you will damage your eyes but you won't feel it. 00:17:59.000 --> 00:17:65.000 The retina that's the part of your eye near the back, the biologists tell me this is true, 00:18:05.000 --> 00:18:09.000 will develop scaring from the energy from the sun 00:18:09.000 --> 00:18:12.000 but the retina does not have any nerves to feel pain. 00:18:12.000 --> 00:18:15.000 So you won't feel the damage as it's happening. 00:18:15.000 --> 00:18:18.000 You can damage or lose your eyesight and never feel a thing. 00:18:18.000 --> 00:18:23.000 That's why it's especially important to watch children and make sure they wear their glasses as well. 00:18:23.000 --> 00:18:28.000 I'm sure that will be no problem at all. I have two. 00:18:28.000 --> 00:18:34.000 OK. Now that we've got our eyes protected let's look in detail at what to expect from this eclipse. 00:18:34.000 --> 00:18:40.000 The eclipse will first start in Depot Bay around 9:04 AM local time. 00:18:40.000 --> 00:18:44.000 As the first part of the shadow the penumbra falls onto your location 00:18:44.000 --> 00:18:47.000 you'll start to notice a clarity to the sunlight 00:18:47.000 --> 00:18:50.000 and if you're wearing your glasses 00:18:50.000 --> 00:18:54.000 you can look at the sun and see a small piece appears to be missing. 00:18:54.000 --> 00:18:58.000 That's the moon starting to cover the disc of the sun. 00:18:58.000 --> 00:18:63.000 As time passes you will start to see less and less of the sun and it will take on a crescent shape. 00:19:03.000 --> 00:19:10.000 If you are outside near trees you may see an interesting effect in the shadows below their branches. 00:19:10.000 --> 00:19:15.000 The space between the leaves acts like a pinhole camera, reflecting an image of the sun. 00:19:15.000 --> 00:19:19.000 Normally we see small circles or dapples in these shadows. 00:19:19.000 --> 00:19:25.000 But during this part of the eclipse you can see crescent shapes in the dapples of the shadows like this picture here. 00:19:25.000 --> 00:19:29.000 I saw this effect when I was in Arizona and a partial eclipse happened. 00:19:29.000 --> 00:19:34.000 When the light went through a small drain at the top of the apartment builiding 00:19:34.000 --> 00:19:38.000 and reflected the image of the sun on the opposite apartment building. It was pretty neat. 00:19:38.000 --> 00:19:44.000 The extent of the crescent you will see will depend on your location in terms of the path of totality. 00:19:44.000 --> 00:19:50.000 If you're outside that path the moon will not line up perfectly with the sun and the crescent shaped sun is the most you will see. 00:19:50.000 --> 00:19:55.000 But if you are in the path of totality as we are in Monmouth 00:19:55.000 --> 00:19:57.000 then things will get more interesting. 00:19:57.000 --> 00:19:61.000 Right before the moon completely covers the sun 00:20:01.000 --> 00:20:05.000 you'll see a flash that is called the diamond ring effect. 00:20:05.000 --> 00:20:09.000 This is when a small ring of light from the sun is still visible around the moon 00:20:09.000 --> 00:20:12.000 and there's a larger flash of light right on the edge. 00:20:12.000 --> 00:20:18.000 That flash of light is light from the sun visible through canyons on the edge of the moon. 00:20:18.000 --> 00:20:23.000 So the picture on the right is showing the canyons on the edge of the moon there. 00:20:23.000 --> 00:20:26.000 So because it's not a perfect sphere you get a little extra light. 00:20:26.000 --> 00:20:31.000 Finally we reach totality. You can take your glasses off. 00:20:31.000 --> 00:20:37.000 In fact you'll have to. It will be too dark to be able to see anything with the glasses on. 00:20:37.000 --> 00:20:41.000 How long totality lasts depends on where you are along the path. 00:20:41.000 --> 00:20:45.000 For most of Oregon totality will last right around two minutes. 00:20:45.000 --> 00:20:50.000 And it will start about an hour after the first contact between the moon and the sun. 00:20:50.000 --> 00:20:53.000 As I said before the world around you will be in darkness. 00:20:53.000 --> 00:20:58.000 It will be noticeably cooler and you can see the sun's corona and the stars in the sky around. 00:20:58.000 --> 00:20:65.000 This August you'll also be able to see the planets Mercury, Venus, Mars, and Jupiter on either side of the sun. 00:21:05.000 --> 00:21:10.000 As the moon and earth continue to rotate in their orbits the moon will begin to uncover the sun 00:21:10.000 --> 00:21:14.000 and you will see the same sequence of events but in reverse. 00:21:14.000 --> 00:21:18.000 The umbra has passed over us and now we're back in the penumbra. 00:21:18.000 --> 00:21:21.000 The opposite side of the sun will start to become uncovered. 00:21:21.000 --> 00:21:24.000 And you may see something called Bailey's Beads. 00:21:24.000 --> 00:21:31.000 This is a grouping of brighter flashes along the edge of the moon which is again light shining through the canyons on the moon. 00:21:31.000 --> 00:21:35.000 When you see these beads it's time to put your glasses back on. 00:21:35.000 --> 00:21:41.000 It will take about another hour for the moon to completely pass by and uncover the sun. 00:21:41.000 --> 00:21:43.000 As it does everything will return to normal. 00:21:43.000 --> 00:21:48.000 Animals will come back out, the temperature will rise, the sky will turn blue again. 00:21:48.000 --> 00:21:53.000 And the euphoria you feel from witnessing the eclipse will be tempered by dealing with the traffic 00:21:53.000 --> 00:21:59.000 of the expected one million visitors to the state of Oregon all suddenly wanting to get home. 00:21:59.000 --> 00:21:65.000 Well I expect most people will simply be planning to watch the eclipse as I am. 00:22:05.000 --> 00:22:10.000 There are 11 NASA-funded science experiments planned for the event. 00:22:10.000 --> 00:22:13.000 Six of the experiments are focused on learning about the sun. 00:22:13.000 --> 00:22:17.000 We currently have satellites that take pictures of the sun and help us monitor space weather. 00:22:17.000 --> 00:22:24.000 But those tools still have to deal with diffraction of the light that blurs the inner parts of the corona. 00:22:24.000 --> 00:22:28.000 This makes it very difficult to get reliable information about that part of our sun. 00:22:28.000 --> 00:22:34.000 It is only during total solar eclipses that scientists can get clear pictures of the corona. 00:22:34.000 --> 00:22:38.000 Making total solar eclipses a very exciting scientific opportunity. 00:22:38.000 --> 00:22:43.000 In the past during a total solar eclipse in 1868 00:22:43.000 --> 00:22:47.000 a scientist observed a never before seen element in our sun's corona. 00:22:47.000 --> 00:22:52.000 This element was ultimately named after the Greek name for our sun Helios. 00:22:52.000 --> 00:22:56.000 Which means the helium you use to fill your party balloons 00:22:56.000 --> 00:22:62.000 was first discovered from observations made during a total solar eclipse. 00:23:02.000 --> 00:23:07.000 There are also five experiments planned to study the earth under uncommon conditions. 00:23:07.000 --> 00:23:12.000 These studies are focused on the rapid changes to light and temperature on the ground 00:23:12.000 --> 00:23:16.000 and the impacts those changes have on weather, plants, and animals. 00:23:16.000 --> 00:23:21.000 No matter how you choose to watch the eclipse this summer it is sure to be a memorable event. 00:23:21.000 --> 00:23:23.000 Remember your safety glasses. 00:23:23.000 --> 00:23:27.000 Find a comfortable seat somewhere along the path of totality. 00:23:27.000 --> 00:23:33.000 And enjoy the spectacular show made possible by the wobble of the earth and the moon as they move through space. 00:23:33.000 --> 00:23:35.000 Thank you. 00:23:35.000 --> 00:23:37.000 applause 00:23:37.000 --> 00:23:55.000 music