WEBVTT - Path of Totality: See the Eclipse! 0:00:03.040 --> 0:00:05.840 Welcome to Stuff to Blow your Mind from how Stuff 0:00:05.880 --> 0:00:14.200 Works dot com. Hey you welcome to Stuff to Blow 0:00:14.240 --> 0:00:17.239 your Mind. My name is Robert Lamb and I'm Joe McCormick. 0:00:17.239 --> 0:00:20.279 And in case you haven't heard, there is a big 0:00:20.320 --> 0:00:23.680 thing coming up for our US listeners. That's right on 0:00:24.040 --> 0:00:31.120 August one, a giant crab monster from another galaxy is 0:00:31.160 --> 0:00:34.240 going to swim into the sky and devour our son 0:00:34.600 --> 0:00:37.240 and we were all going to die. No, not our son. 0:00:37.360 --> 0:00:40.920 That's where we get our light and stuff. Uh, not quite. 0:00:40.960 --> 0:00:44.680 There is going to be a total solar eclipse sweeping 0:00:44.760 --> 0:00:48.640 across the center of the United States on Monday, August. 0:00:49.880 --> 0:00:51.920 Some people have asked us about it. I have asked 0:00:51.960 --> 0:00:54.480 us on social media and said, hey, are you gonna 0:00:54.480 --> 0:00:56.280 do anything about the eclipse? So we thought as a 0:00:56.320 --> 0:00:59.480 special treat we would discuss the solar eclipse. Now, we've 0:00:59.480 --> 0:01:03.000 talked about eclipses before in episodes like Gazing into the 0:01:03.040 --> 0:01:05.679 Eclipse from May. I think that was one of the 0:01:05.720 --> 0:01:08.840 first episodes of the show I ever did um, but 0:01:08.959 --> 0:01:13.200 today we wanted to go deep on the total solar eclipse. Now, 0:01:13.319 --> 0:01:16.440 this episode will have some practical tips for viewing a 0:01:16.480 --> 0:01:18.800 solar eclipse if you're planning on trying to make it 0:01:18.840 --> 0:01:22.320 to the line of totality for for this upcoming one. 0:01:22.440 --> 0:01:24.760 But we'll also try to do our best to keep 0:01:24.800 --> 0:01:26.440 it interesting for those of you who aren't going to 0:01:26.520 --> 0:01:28.120 be able to view this one. Maybe you'll get to 0:01:28.160 --> 0:01:31.720 view a solar eclipse wherever you are sometime in the future. Yeah, 0:01:31.800 --> 0:01:33.680 So our hope is that this is an episode. Maybe 0:01:33.680 --> 0:01:36.400 you'll play it in the car while driving up or 0:01:36.520 --> 0:01:39.640 or while you're stuck in traffic driving up to UH 0:01:39.640 --> 0:01:42.360 to the line of totality, or perhaps you'll play it 0:01:42.360 --> 0:01:44.560 on the way back to make you better sense of 0:01:44.600 --> 0:01:47.760 what you saw. You just saw a total solar eclipse. 0:01:48.000 --> 0:01:51.080 Now let's talk about the you know, the celestial mechanics 0:01:51.080 --> 0:01:54.520 of what was happening there. Alright, So a solar eclipse 0:01:55.200 --> 0:01:58.080 or any eclipse really is an example of what's known 0:01:58.120 --> 0:02:00.480 as a scissor gy. I think I used to pronounce 0:02:00.520 --> 0:02:02.080 that word wrong. I think I was calling it like 0:02:02.200 --> 0:02:05.280 sizzygi or well it's a word that's spelled s y 0:02:05.520 --> 0:02:12.600 z y g y. So it really the dictionary factory. Yes, yes, 0:02:12.720 --> 0:02:15.000 sissy gy is a word that comes from the Greek 0:02:15.320 --> 0:02:19.519 susa Joss or susy goos and scissor giant meaning yoked together, 0:02:20.120 --> 0:02:22.400 and of course a yoke. You've probably seen one of these, 0:02:22.520 --> 0:02:25.080 especially if you've ever played organ trail. It's a solid 0:02:25.160 --> 0:02:28.800 cross beam that attaches two animals by the neck. So 0:02:28.880 --> 0:02:32.120 if you need two oxen to pull your plow to 0:02:32.280 --> 0:02:34.560 turn the soil in the field where you're growing your 0:02:34.600 --> 0:02:37.960 first crop of alien pod people, you yoke the oxen 0:02:38.000 --> 0:02:41.639 together and they'll pull you together. But in astronomy, yoking 0:02:41.760 --> 0:02:45.760 implies gravitational binding. Of course, we all know the Moon 0:02:45.960 --> 0:02:48.880 is gravitationally bound to the Earth and the Earth is 0:02:48.880 --> 0:02:52.360 gravitationally bound to the Sun. And since the orbits of 0:02:52.400 --> 0:02:54.600 the Earth and the Moon are on pretty close to 0:02:54.639 --> 0:02:57.200 the same plane, but not exactly the same plane, we 0:02:57.280 --> 0:03:03.079 get infrequent solar eclipses across different sections of the Earth's surface. 0:03:03.639 --> 0:03:06.600 And what happens there is pretty straightforward. A total solar 0:03:06.639 --> 0:03:10.880 eclipse occurs when the Moon passes between the Earth and 0:03:10.919 --> 0:03:15.240 the Sun, blocking the Sun's light. Yeah, it just kind 0:03:15.280 --> 0:03:17.400 of it works out just kind of perfectly there, right, 0:03:17.480 --> 0:03:21.080 because the Moon is just the right size to to 0:03:21.240 --> 0:03:25.200 completely block out the Sun as visible from Earth. Yeah, 0:03:25.240 --> 0:03:27.720 and you might wonder why is it such a perfect fit. 0:03:27.840 --> 0:03:30.760 Is there some feature of orbital mechanics that makes it 0:03:30.800 --> 0:03:33.760 that way. No, it's actually a complete coincidence. We just 0:03:33.800 --> 0:03:37.720 got really lucky that our moon is almost exactly the 0:03:37.800 --> 0:03:41.280 same size as our apparent Sun. If Earth's moon were 0:03:41.280 --> 0:03:44.120 smaller in diameter, or if it were farther away from 0:03:44.160 --> 0:03:46.680 the Earth, which it will be further along in Earth's 0:03:46.720 --> 0:03:49.360 history and millions of years, the Moon's going to be 0:03:49.480 --> 0:03:52.680 further out in its orbit, and thus it will it 0:03:52.720 --> 0:03:55.360 will alter the way we have eclipses on Earth's surface. 0:03:55.760 --> 0:03:58.440 But but if the Moon were smaller, if it were 0:03:58.480 --> 0:04:01.280 farther away, it would be apparently smaller than the Sun. 0:04:01.600 --> 0:04:04.840 So instead of covering the Sun completely, it would pass 0:04:04.960 --> 0:04:08.800 across the face of the Sun as a large black dot. 0:04:09.120 --> 0:04:12.240 And you can observe other planets like Venus and Mercury 0:04:12.320 --> 0:04:14.840 already doing this if you have the right kind of telescope. 0:04:14.880 --> 0:04:17.880 For example, if you've never looked up images of the 0:04:17.920 --> 0:04:21.000 transit of Venus, you should check it out. It's really cool. 0:04:21.080 --> 0:04:23.480 You can see that this black dot is the planet 0:04:23.560 --> 0:04:27.640 passes in front of the sun disk. Another way you 0:04:27.640 --> 0:04:31.279 can observe this difference is if you observe moons doing 0:04:31.320 --> 0:04:33.400 this as they line up in sissy g e on 0:04:33.480 --> 0:04:36.760 the surface of other planets. For example, you get the 0:04:36.800 --> 0:04:41.240 Curiosity rover and you turn its camera up so it 0:04:41.320 --> 0:04:45.360 looks towards the Sun. You can observe solar eclipses on 0:04:45.520 --> 0:04:49.560 Mars as the Martian moon Phobos passes in front of 0:04:49.600 --> 0:04:52.719 the Sun. Except it's not really a total eclipse, and 0:04:52.760 --> 0:04:56.119 it never could be because even when Phobos passes dead 0:04:56.200 --> 0:04:59.320 center across the Sun, it's too small to cover up 0:04:59.360 --> 0:05:02.120 the Sun. So in said, it's like a big black 0:05:02.240 --> 0:05:04.680 pupil in the middle of the Sun. As an eye, 0:05:04.760 --> 0:05:08.120 it looks like a big Google eye. I've seen it 0:05:08.160 --> 0:05:09.680 does look like a big Google eye. It's like one 0:05:09.720 --> 0:05:11.920 of those things that did you ever like make those 0:05:12.000 --> 0:05:14.200 little Google eyed toys when you were a kid. You 0:05:14.200 --> 0:05:16.280 can buy old Google eyes at the When I was 0:05:16.360 --> 0:05:20.320 a kid, I've I've never stopped making. For a while, 0:05:20.600 --> 0:05:23.359 I was daring enough to carry around a pack of 0:05:23.400 --> 0:05:26.840 Google eyes and stick them to various signs on our 0:05:26.920 --> 0:05:30.560 local transportation uh, this public transportation system here in Atlanta. 0:05:30.640 --> 0:05:32.600 But but then I got a little scared and stop 0:05:32.680 --> 0:05:34.599 doing it. Why do you get scared and I was 0:05:34.640 --> 0:05:36.919 just a friend like this, I just decided this is 0:05:36.920 --> 0:05:39.320 a silly thing to get in legal trouble for like 0:05:39.680 --> 0:05:42.159 I would hate to be the guy who's arrested for 0:05:42.200 --> 0:05:46.080 putting Google eyes on a on an advertisement, Like is 0:05:46.120 --> 0:05:48.839 this worth the hilarity? And it it was. It was 0:05:48.880 --> 0:05:51.240 a tough decision, but I ultimately decided it was not. 0:05:51.520 --> 0:05:54.599 You know the name of Phobos, the Martian moon, Phobos 0:05:54.640 --> 0:05:57.080 means fear, but it apparently is not afraid of the 0:05:57.120 --> 0:06:00.800 same thing you were becauause up Google eyes the periodically 0:06:00.920 --> 0:06:03.760 make a Google I right on its parent star. Now, 0:06:04.279 --> 0:06:08.160 if you know the right equations to calculate angular diameter 0:06:08.279 --> 0:06:11.240 by distance, that's by saying, okay, if I know how 0:06:11.240 --> 0:06:13.919 big something is and how far away it is, I 0:06:13.920 --> 0:06:16.520 can calculate how many degrees of my view it's going 0:06:16.560 --> 0:06:18.960 to take up. Or if you just have a handy 0:06:19.000 --> 0:06:21.560 online calculator that does this and I came across a 0:06:21.600 --> 0:06:24.400 few you can actually go back and resolve this to 0:06:24.440 --> 0:06:26.600 find out how much of your field of view. Various 0:06:26.600 --> 0:06:30.760 planetary objects will take up at different distances. For example, 0:06:30.800 --> 0:06:33.240 the average distance from the Earth to the Sun is 0:06:33.240 --> 0:06:36.560 about a hundred and fifty million kilometers, and the diameter 0:06:36.720 --> 0:06:39.800 of the Sun is about one point four million kilometers. 0:06:40.080 --> 0:06:42.479 It works out too that the Sun takes up about 0:06:42.560 --> 0:06:46.560 zero point five three degrees of view. Meanwhile, the average 0:06:46.600 --> 0:06:48.720 distance from the Earth to the Moon is about three 0:06:48.920 --> 0:06:52.120 d and eight four thousand, four hundred kilometers, and the 0:06:52.160 --> 0:06:55.960 average diameter and not the average, the equatorial diameter of 0:06:56.000 --> 0:06:59.680 the Moon is three thousand, four hundred and seventy six kilometers. 0:07:00.000 --> 0:07:02.440 If you calculate that, it also takes up just a 0:07:02.480 --> 0:07:05.200 little over half of a degree of view, about zero 0:07:05.240 --> 0:07:08.080 point five one eight and so on. Average both are 0:07:08.120 --> 0:07:11.000 about half a degree, and since degrees are usually broken 0:07:11.000 --> 0:07:13.280 down into units of sixty, argument, it's both are just 0:07:13.440 --> 0:07:16.640 over thirty arc minutes in the sky, so they can 0:07:16.720 --> 0:07:19.880 line up so that the Moon just perfectly blocks out 0:07:19.880 --> 0:07:22.600 the Sun. It's a beautiful fact about Earth that makes 0:07:22.680 --> 0:07:26.240 us special. Now here's the question, Joe, that I imagine 0:07:26.280 --> 0:07:29.360 a number of people have have pondered, is uh, like 0:07:29.560 --> 0:07:33.480 the rarity of a solar eclipse? Because like for me, 0:07:33.600 --> 0:07:38.080 I have never witnessed a total solar eclipse, and therefore 0:07:38.160 --> 0:07:39.800 I'm very excited, like this is the first time in 0:07:39.840 --> 0:07:42.040 my life it'll be the first time in my my 0:07:42.120 --> 0:07:45.880 son's young life. And you know, I'm not sure when 0:07:45.880 --> 0:07:49.120 my next opportunity will will truly come, so I'm gonna 0:07:49.240 --> 0:07:51.480 pounce on it. But but why is it so rare 0:07:51.560 --> 0:07:55.120 if it's just tied up with the very predictable movements 0:07:55.320 --> 0:07:58.520 of of our celestial bodies. Yeah, this is an interesting question. 0:07:58.560 --> 0:08:01.520 So if the Earth orbits the Sun onneon and the 0:08:01.560 --> 0:08:04.920 Moon makes a full orbit around the Earth roughly once 0:08:04.960 --> 0:08:08.240 a month, how come there is not a solar eclipse 0:08:08.480 --> 0:08:11.720 every single month? Think about it, right, So, if it's 0:08:11.720 --> 0:08:14.480 going around the Earth once a month, shouldn't it pass 0:08:14.560 --> 0:08:18.120 directly between the Earth and the Sun once a month. Well, 0:08:18.160 --> 0:08:21.600 it actually does this from one direction, but it doesn't 0:08:21.640 --> 0:08:24.800 from the other direction. So the reason this doesn't happen 0:08:24.840 --> 0:08:26.960 every month is that the orbit of the Moon is 0:08:27.000 --> 0:08:31.240 not exactly flat with respect to Earth's orbit around the Sun. 0:08:31.280 --> 0:08:33.560 And we can call Earth's orbit around the Sun the 0:08:33.640 --> 0:08:35.960 solar plane. Think of that is taking place on a 0:08:35.960 --> 0:08:39.319 flat table. Now, if you're looking top down on this 0:08:39.400 --> 0:08:41.640 flat table at the Earth and the Sun, the Moon 0:08:41.760 --> 0:08:45.040 goes in an oval shaped elliptical orbit around the Earth. 0:08:45.280 --> 0:08:47.480 But if you get down and look across that table 0:08:47.520 --> 0:08:49.800 across the plane. So that the Earth's orbit around the 0:08:49.800 --> 0:08:53.000 Sun is flat, the Moon's orbit around the Earth is 0:08:53.040 --> 0:08:56.640 going to be slightly tipped to the side, tilted just 0:08:56.720 --> 0:08:59.319 about five degrees off. So think of it like a 0:08:59.360 --> 0:09:03.400 wide brim hat, just slightly cocked to the side. And 0:09:03.440 --> 0:09:06.000 so what that means is most of the time, the 0:09:06.000 --> 0:09:09.760 Moon is not directly on that flat plane between the 0:09:09.800 --> 0:09:13.600 Earth and the Sun and just intersects that plane twice 0:09:13.640 --> 0:09:16.920 every month, once going up and once coming down north 0:09:16.960 --> 0:09:20.040 to south ooh, and south to north. So the only 0:09:20.080 --> 0:09:22.440 time you get a solar eclipse is when these two 0:09:22.480 --> 0:09:27.360 intersections happen at the same time, you know, by coincidence. 0:09:27.600 --> 0:09:30.280 So when the Moon passes between the Earth and the 0:09:30.320 --> 0:09:34.080 Sun on the east west axis and when it just 0:09:34.200 --> 0:09:38.679 happens to be simultaneously crossing the solar plane across the 0:09:38.720 --> 0:09:42.000 north south axis, that's when you get a solar eclipse. 0:09:43.080 --> 0:09:46.800 Now that being said, obviously every solar eclipse is not 0:09:46.920 --> 0:09:50.440 a total solar eclipse. We have a few different varieties here, right, 0:09:50.480 --> 0:09:52.840 So you've got the partial solar eclipse. This is the 0:09:52.880 --> 0:09:56.320 pac Man eclipse. Uh, the Moon partially blocks out the 0:09:56.320 --> 0:09:58.720 Sun it'll some people would say it takes a bite 0:09:58.720 --> 0:10:00.360 out of the Sun and giving it a press and 0:10:00.440 --> 0:10:04.800 appearance and a brief, sometimes undetectable dip and luminosity depending 0:10:04.800 --> 0:10:06.480 on how much of it, how much of the Moon 0:10:06.880 --> 0:10:09.800 is crossing the Sun, based on your vantage point. And 0:10:09.800 --> 0:10:12.720 in this type of eclipse, the Moon never completely blocks 0:10:12.720 --> 0:10:15.560 out the Sun. So these happen fairly often and they're 0:10:15.600 --> 0:10:18.600 not as startling or as you know, attention getting as 0:10:18.640 --> 0:10:22.240 a total solar eclipse. A total solar eclipse is when 0:10:22.280 --> 0:10:25.880 the Moon completely blocks out the Sun, causing darkness at 0:10:25.960 --> 0:10:28.360 day and the ability to look up at the sun 0:10:28.480 --> 0:10:32.280 disk blocked with the naked eye and see the corona 0:10:32.360 --> 0:10:35.360 around the Sun. Now, I want to modify naked eye 0:10:35.360 --> 0:10:38.240 in a minute, because there are some important precautions you'll 0:10:38.240 --> 0:10:40.120 need to take if you're going to be viewing the 0:10:40.160 --> 0:10:42.240 solar eclipse this year. Now, I do want to throw 0:10:42.280 --> 0:10:44.640 in real quick, we're not really talking about lunar eclipses 0:10:45.000 --> 0:10:48.840 in this episode. But what's occurring there is you're seeing 0:10:49.000 --> 0:10:52.480 um that the shadow of the Earth cast upon the Moon, right, 0:10:52.520 --> 0:10:55.040 So it's going to be the opposite side effect of 0:10:55.080 --> 0:10:57.600 the solar eclipse. It's when the Moon happens to be 0:10:57.679 --> 0:11:01.040 crossing the solar plane at the same time that it's 0:11:01.080 --> 0:11:04.960 directly behind the Earth on the east west axis. Alright, 0:11:05.000 --> 0:11:07.920 so solar eclipse that we have partial, we have total. 0:11:08.080 --> 0:11:10.800 What else do we have. We've also got the annular eclipse, 0:11:10.800 --> 0:11:12.880 and this one is kind of interesting. So this is 0:11:12.920 --> 0:11:15.960 when you would have a total eclipse. It's when the 0:11:16.000 --> 0:11:19.160 Moon does pass directly in front of the Sun from 0:11:19.200 --> 0:11:23.280 your point of view, but it never completely blocks the Sun. Instead, 0:11:23.360 --> 0:11:27.160 what happens is it leaves an always visible ring of 0:11:27.280 --> 0:11:31.000 sunlight around it. If one of these is happening, you 0:11:31.040 --> 0:11:33.679 should not look at the annular eclipse of the naked 0:11:33.679 --> 0:11:35.440 eye because a lot of the sunlight is still going 0:11:35.480 --> 0:11:38.120 to be getting through. Now you might be thinking, wait 0:11:38.120 --> 0:11:40.280 a minute, how can that happen, because didn't we just 0:11:40.360 --> 0:11:43.040 talk about how from our perspective, the Moon and the 0:11:43.040 --> 0:11:46.160 Sun are the same size. Well, they they're about the 0:11:46.200 --> 0:11:50.679 same size on average, But those averages are just averages. 0:11:50.760 --> 0:11:53.560 So the apparent size of the Sun and the Moon 0:11:53.960 --> 0:11:57.200 can both vary depending on where they are in their orbits. 0:11:58.000 --> 0:12:00.080 In both cases, I was calculating on the base of 0:12:00.120 --> 0:12:03.400 average distances. Uh, and so the Earth and the Moon 0:12:03.559 --> 0:12:08.040 both have elliptical orbits around their their gravitational parents rather 0:12:08.080 --> 0:12:11.520 than perfectly circular ones. When the Moon is closest to 0:12:11.559 --> 0:12:15.320 the Earth, this is called the parage, it looks bigger, 0:12:15.720 --> 0:12:18.079 and when the Moon is farthest from the Earth, of course, 0:12:18.080 --> 0:12:20.880 this is called the apoge it looks smaller. Likewise, there's 0:12:20.920 --> 0:12:24.280 a tiny amount of variation in how big the Sun looks, 0:12:24.280 --> 0:12:27.120 given whether the Earth is closest in its orbit or 0:12:27.160 --> 0:12:30.320 farther away in its orbit. So if the Moon is 0:12:30.360 --> 0:12:33.360 at a lower apparent diameter and the Sun's at a 0:12:33.400 --> 0:12:37.199 greater apparent diameter, the Moon could fall directly in the 0:12:37.240 --> 0:12:40.040 middle of the Sun and still not block the whole thing. 0:12:40.160 --> 0:12:42.040 So you get a ring of light in the sky, 0:12:42.440 --> 0:12:45.840 and this is what's known as the annular eclipse. There's 0:12:45.880 --> 0:12:48.640 also another rare type of eclipse called the hybrid eclipse, 0:12:48.679 --> 0:12:51.760 and this this happens when the apparent diameters of the 0:12:51.800 --> 0:12:53.480 Sun and the Moon are sort of right on the 0:12:53.520 --> 0:12:56.959 boundary of going from annular to total. So some people 0:12:57.000 --> 0:12:59.600 on the Earth will see an annular eclipse, and people 0:12:59.640 --> 0:13:02.440 in other locations we'll see a total solar eclipse. And 0:13:02.440 --> 0:13:04.440 this is when we have werewolves, right, because there, of 0:13:04.440 --> 0:13:07.320 course the hybrid of man and wolf. I mean, when 0:13:07.320 --> 0:13:10.600 else would we have werewolves. It's the prime opportunity. It's 0:13:10.640 --> 0:13:13.560 important that you point out that the solar eclipse has 0:13:13.640 --> 0:13:16.800 these kind of supernatural connotations. We we talked in our 0:13:16.840 --> 0:13:20.080 other eclipse episode about many of the myths associated with eclipses, 0:13:20.320 --> 0:13:23.880 but there are particular myths associated with the total solar eclipses, right. 0:13:24.280 --> 0:13:26.800 Oh yeah, I mean it makes sense right that you 0:13:26.800 --> 0:13:30.240 have this this cosmic event. You know, early early people 0:13:30.240 --> 0:13:33.320 are looking up into the uh at the stars, at 0:13:33.360 --> 0:13:35.360 the sun and the moon and trying to make sense 0:13:35.400 --> 0:13:39.360 of what's occurring there. They have myths that are that 0:13:39.480 --> 0:13:42.359 in some cases have been created to explain natural phenomena, 0:13:42.559 --> 0:13:44.800 but in other cases, you know, kind of exist on 0:13:44.840 --> 0:13:48.640 their own but then get reinterpreted in the light of 0:13:48.760 --> 0:13:51.360 natural phenomena. We've talked about this sort of interplay and 0:13:51.520 --> 0:13:56.000 varying theories of of of natural phenomena and mythology before. 0:13:57.160 --> 0:13:59.079 But the result is, yeah, you have a number of 0:14:00.280 --> 0:14:04.880 a number of monsters and monstrous creatures that are said 0:14:04.960 --> 0:14:08.160 to eat the sun or the moon, or attempt to 0:14:08.200 --> 0:14:10.959 eat the sun or the moon. Uh. For instance, in 0:14:11.000 --> 0:14:15.840 the case of the the Indian UH entity Raju Uh, 0:14:15.880 --> 0:14:18.560 he's this decapitated head and it has said that he 0:14:18.600 --> 0:14:20.720 eats the sun, but then the sun falls back out 0:14:20.720 --> 0:14:23.320 of his next jump because he has has no body. 0:14:23.640 --> 0:14:26.280 And we talk about that myth in detail in our 0:14:26.320 --> 0:14:28.440 our Past eclipse episode, which will be linked to on 0:14:28.480 --> 0:14:30.280 the landing page for this episode is stuff to blow 0:14:30.320 --> 0:14:32.840 your mind dot com. That is such a visceral and 0:14:32.960 --> 0:14:35.880 wonderful myth. It's like it's like something you'd see in 0:14:35.880 --> 0:14:38.680 an itchy and scratchy cartoon. Yes, I don't mean to denigrated. 0:14:38.760 --> 0:14:42.000 I mean it's just like so it's so gory. Oh yeah. 0:14:42.000 --> 0:14:43.440 And I didn't even get into the details of the 0:14:43.520 --> 0:14:48.480 decapitation where he's decapitated with this divine weapon that's kind 0:14:48.480 --> 0:14:51.800 of like the spinning weapon and crawl. So it's it's 0:14:51.840 --> 0:14:54.240 it's a pretty delightful episode. It's one of my favorite 0:14:54.400 --> 0:14:58.320 UH eclipse myths for sure. Well, it's not a surprise 0:14:58.480 --> 0:15:01.960 that the eclipse call as people to think of the supernatural, 0:15:02.000 --> 0:15:05.040 because it's one of the most awe inspiring sites in nature. 0:15:05.080 --> 0:15:08.200 It's hard to think of something that without the aid 0:15:08.240 --> 0:15:12.800 of technology, humans can see that is so unbelievable and 0:15:12.880 --> 0:15:15.400 so alien to our day to day experience. And we're 0:15:15.400 --> 0:15:18.880 talking about the sun going dark. Uh it this is 0:15:18.920 --> 0:15:20.880 the kind of thing that ties into at least two 0:15:20.880 --> 0:15:25.160 different apocalypse smiths, both the Christian Apocalypse as well as 0:15:25.640 --> 0:15:29.480 North Ragnarok. Yeah, it seems like a literal challenge to 0:15:29.560 --> 0:15:33.440 the established order of the cosmos night and day light 0:15:33.520 --> 0:15:37.080 and dark sun in the moon. It's completely destabilizing. So 0:15:37.120 --> 0:15:39.520 it's just no wonder that many people throughout history have 0:15:39.640 --> 0:15:43.120 reacted to it with sheer terror. Now, apart from the 0:15:43.160 --> 0:15:45.720 traffic that you may expect, we hope you will not 0:15:45.840 --> 0:15:48.680 react to this eclipse with sheer terror, but with all 0:15:48.720 --> 0:15:52.600 the wonder that's due to this fantastic demonstration of physics 0:15:52.600 --> 0:15:55.720 and nature at work. So maybe when we come back 0:15:55.760 --> 0:15:58.520 from a quick break, we will talk about this upcoming 0:15:58.560 --> 0:16:06.960 eclipse in August of only seventeen. All right, we're back. So, Joe, 0:16:06.960 --> 0:16:08.960 I don't know do you have plans yet for the eclipse. 0:16:09.120 --> 0:16:11.680 I'm still trying to make up my mind about what 0:16:11.720 --> 0:16:16.080 I'm gonna do. I've got several options, and I'm I'm 0:16:16.240 --> 0:16:19.520 so disclosure here. Robert and I we live in Atlanta here, 0:16:19.600 --> 0:16:23.760 so we're pretty close to the line of totality, and 0:16:23.840 --> 0:16:26.840 so Robert, I know you have some plans. Yeah, the 0:16:26.880 --> 0:16:29.000 family and I are going to drive up to the 0:16:29.040 --> 0:16:33.840 mountains and uh and seek the total eclipse. Nice. So 0:16:34.000 --> 0:16:36.800 if you live almost anywhere in the United States, you 0:16:36.880 --> 0:16:40.040 will be able to see a partial solar eclipse, which 0:16:40.120 --> 0:16:43.040 is the Moon's shadow passing over part of the Sun. 0:16:44.040 --> 0:16:46.840 But there are other chances that people are going to 0:16:46.920 --> 0:16:49.920 have to see that. Impartial solar eclipses are much easier 0:16:49.960 --> 0:16:52.760 to see because they just affect a much larger portion 0:16:52.840 --> 0:16:55.880 of the Earth's surface. If you were within what's called 0:16:56.000 --> 0:16:59.200 the line of totality, you will get to see a 0:16:59.240 --> 0:17:04.040 total soul eclipse on Monday, August one, and that's the 0:17:04.080 --> 0:17:07.520 Moon passing straight in front of the Sun and completely 0:17:07.560 --> 0:17:10.680 blocking it out. So the line of totality is about 0:17:10.760 --> 0:17:14.000 seventy miles or about a hundred and ten kilometers wide. 0:17:14.400 --> 0:17:17.359 If you're within that line, that's where the total solar 0:17:17.400 --> 0:17:20.600 eclipse will happen. And the total eclipse will start in 0:17:20.760 --> 0:17:24.480 northern central Oregon um at about ten fifteen am. I 0:17:24.480 --> 0:17:27.400 think they say first contact, which is when the sun 0:17:27.560 --> 0:17:31.040 very first touches the Moon. That's going to happen sometime 0:17:31.040 --> 0:17:34.560 closer to nine am Pacific time over there, but first 0:17:34.600 --> 0:17:37.680 will happen about ten fifteen am Pacific time, and it's 0:17:37.680 --> 0:17:40.159 slowly going to pass over the United States, and a 0:17:40.240 --> 0:17:47.960 line running southeast from Oregon through Idaho, Wyoming, Nebraska, Missouri, Kentucky, Tennessee, Georgia, 0:17:48.000 --> 0:17:50.960 and South Carolina, also touching small parts of a few 0:17:50.960 --> 0:17:53.280 other states. You can look up a map online. There 0:17:53.280 --> 0:17:55.879 are a bunch of them. NASA has done one all right. Now, 0:17:55.880 --> 0:17:59.000 we've already talked about the rarity of solar eclipse, but 0:17:59.080 --> 0:18:02.440 just just how rare are they really? Well, there's sort 0:18:02.480 --> 0:18:06.160 of a misconception actually that solar eclipses are extremely rare 0:18:06.400 --> 0:18:10.840 on principle, and actually solar eclipses and lunar eclipses happen 0:18:10.920 --> 0:18:13.360 it pretty close to the same rate, if I think, 0:18:13.400 --> 0:18:16.359 if you count pennumber lunar eclipses, lunar eclipses are a 0:18:16.359 --> 0:18:20.480 little bit more common. According to the Belgian astronomers gen Mayas, 0:18:20.480 --> 0:18:23.160 in the twentieth century, there were two hundred and twenty 0:18:23.200 --> 0:18:26.280 eight solar eclipses and two d and twenty nine lunar eclipses, 0:18:26.480 --> 0:18:30.720 So they're not actually a rare phenomenon in themselves. But 0:18:30.800 --> 0:18:34.200 what's rare is for a total solar eclipse to pass 0:18:34.280 --> 0:18:38.280 over wherever you happen to be. So, as as we 0:18:38.320 --> 0:18:41.359 discussed a minute ago, not all solar eclipses are total eclipses. 0:18:41.359 --> 0:18:44.600 Some are partial or annular. And solar eclipses happen all 0:18:44.600 --> 0:18:47.320 the time, but you probably won't get many chances in 0:18:47.320 --> 0:18:50.080 your life to see one unless you have the resources 0:18:50.119 --> 0:18:53.000 to travel around the globe and chase these lines of 0:18:53.040 --> 0:18:57.359 totality wherever they happen to be falling. All right, so 0:18:57.680 --> 0:19:00.560 let's get let's get down to brass tacks here. Okay, 0:19:01.080 --> 0:19:03.600 driving up to uh, you know, the line of totality 0:19:03.680 --> 0:19:06.240 is one thing, right, you know, maybe you're close to it, 0:19:06.280 --> 0:19:08.680 maybe you're far away, but with enough planning you can 0:19:08.720 --> 0:19:11.840 get there staring at the sun the whole way. Because 0:19:11.880 --> 0:19:15.119 that's the thing that what does one need to protect 0:19:15.359 --> 0:19:19.240 themselves while staring at the sign, while staring up even 0:19:19.240 --> 0:19:22.480 at a sun that is about to be obscured, uh 0:19:22.520 --> 0:19:25.520 by the moon. Uh? You know what, we have all 0:19:25.560 --> 0:19:28.000 these special glasses that are suddenly on the market. I mean, 0:19:28.160 --> 0:19:31.080 you can even buy them. I saw them at lows. Uh, 0:19:31.200 --> 0:19:33.720 why are these necessary? I was talking to a good 0:19:33.720 --> 0:19:36.320 friend of ours and and he was like, I mean 0:19:36.560 --> 0:19:39.000 he's he's a cautious dude. But he was like, yeah, 0:19:39.000 --> 0:19:40.919 I think you think you can probably look at the 0:19:40.920 --> 0:19:44.119 eclipse and you'll be all right. Just the same as 0:19:44.160 --> 0:19:47.040 you should never look directly at the sun without proper 0:19:47.080 --> 0:19:49.800 eye protection. You should never look directly at part of 0:19:49.840 --> 0:19:52.920 the sun without proper eye protection. And if you're thinking, 0:19:53.640 --> 0:19:57.399 says you, you know you big buzz kill. Uh maybe 0:19:57.400 --> 0:19:59.680 you think people have been looking at eclipses for thousands 0:19:59.720 --> 0:20:03.000 of years it is, without special goggles. And they were fine, No, really, 0:20:03.640 --> 0:20:06.480 I've been reading about this. Don't look at the sun 0:20:06.720 --> 0:20:10.720 or even part of the sun. Here's what could happen. Uh. 0:20:10.760 --> 0:20:13.240 First of all, there if you want to hear it 0:20:13.280 --> 0:20:16.080 directly from an expert, there's a very quick interview that 0:20:16.119 --> 0:20:19.680 news Week did with Dr Christopher Quinn, who's the president 0:20:19.680 --> 0:20:23.240 of the American Optimetric Association, about what kinds of injuries 0:20:23.280 --> 0:20:25.359 result from looking at the sun without protection. You can 0:20:25.359 --> 0:20:27.560 go check that out if you want, but I'll give 0:20:27.600 --> 0:20:33.600 you the basic rundown. One possibility is photocarrotitis. So photocarrotitis 0:20:33.640 --> 0:20:36.920 is usually described as a sunburn of the eye. It's 0:20:36.920 --> 0:20:40.400 not pleasant sounding at all. Yeah yeah, and you can't 0:20:40.400 --> 0:20:43.680 really rub alo on your eye volcan now. So it's 0:20:43.720 --> 0:20:47.919 when UV radiation ultra violet radiation causes damage to the 0:20:48.040 --> 0:20:51.639 cornea and the conjunctiva, which are the outer surfaces of 0:20:51.680 --> 0:20:56.280 the eyeball, and symptoms include pain, a feeling of having 0:20:56.400 --> 0:20:59.920 grit or another foreign body in the eye. Red eye 0:21:00.080 --> 0:21:05.359 is swelling, sensitivity to light, excessive tearing, and sometimes temporary 0:21:05.440 --> 0:21:09.800 loss of vision. So welding arcs produce UV radiation, and 0:21:09.800 --> 0:21:11.720 this is what can happen to a lot of welders 0:21:11.760 --> 0:21:14.479 if they don't use safety goggles or welding glass when 0:21:14.480 --> 0:21:18.680 they're doing their work. Uh. The photocarrotitis is also sometimes 0:21:18.840 --> 0:21:21.240 referred to as snow blindness. I know you've heard of 0:21:21.280 --> 0:21:24.439 snowboy in this. The reason it's linked to snow is 0:21:24.480 --> 0:21:27.160 that snow covered ground tends to reflect a much greater 0:21:27.280 --> 0:21:31.520 percent of UV radiation than most other natural surfaces like 0:21:31.640 --> 0:21:34.760 grass or soil usually reflect only about ten percent of 0:21:34.800 --> 0:21:38.440