Path of Totality: See the Eclipse!

There is going to be a total solar eclipse sweeping across the center of the United States on Monday, August. Some people have asked us about it. I have asked us on social media and said, hey, are you gonna do anything about the eclipse? So we thought as a special treat we would discuss the solar eclipse. Now, we've talked about eclipses before in episodes like Gazing into the Eclipse from May. I think that was one of the first episodes of the show I ever did um, but

today we wanted to go deep on the total solar eclipse. Now, this episode will have some practical tips for viewing a solar eclipse if you're planning on trying to make it to the line of totality for for this upcoming one. But we'll also try to do our best to keep it interesting for those of you who aren't going to be able to view this one. Maybe you'll get to view a solar eclipse wherever you are sometime in the future. Yeah,

So our hope is that this is an episode. Maybe you'll play it in the car while driving up or or while you're stuck in traffic driving up to UH to the line of totality, or perhaps you'll play it on the way back to make you better sense of what you saw. You just saw a total solar eclipse. Now let's talk about the you know, the celestial mechanics of what was happening there. Alright, So a solar eclipse or any eclipse really is an example of what's known as a scissor gy. I think I used to pronounce

that word wrong. I think I was calling it like sizzygi or well it's a word that's spelled s y z y g y. So it really the dictionary factory. Yes, yes, sissy gy is a word that comes from the Greek susa Joss or susy goos and scissor giant meaning yoked together, and of course a yoke. You've probably seen one of these, especially if you've ever played organ trail. It's a solid

cross beam that attaches two animals by the neck. So if you need two oxen to pull your plow to turn the soil in the field where you're growing your first crop of alien pod people, you yoke the oxen together and they'll pull you together. But in astronomy, yoking

implies gravitational binding. Of course, we all know the Moon is gravitationally bound to the Earth and the Earth is gravitationally bound to the Sun. And since the orbits of the Earth and the Moon are on pretty close to the same plane, but not exactly the same plane, we get infrequent solar eclipses across different sections of the Earth's surface. And what happens there is pretty straightforward. A total solar eclipse occurs when the Moon passes between the Earth and

the Sun, blocking the Sun's light. Yeah, it just kind of it works out just kind of perfectly there, right, because the Moon is just the right size to to completely block out the Sun as visible from Earth. Yeah, and you might wonder why is it such a perfect fit. Is there some feature of orbital mechanics that makes it

that way. No, it's actually a complete coincidence. We just got really lucky that our moon is almost exactly the same size as our apparent Sun. If Earth's moon were smaller in diameter, or if it were farther away from the Earth, which it will be further along in Earth's history and millions of years, the Moon's going to be further out in its orbit, and thus it will it will alter the way we have eclipses on Earth's surface.

But but if the Moon were smaller, if it were farther away, it would be apparently smaller than the Sun. So instead of covering the Sun completely, it would pass across the face of the Sun as a large black dot. And you can observe other planets like Venus and Mercury already doing this if you have the right kind of telescope. For example, if you've never looked up images of the transit of Venus, you should check it out. It's really cool. You can see that this black dot is the planet

passes in front of the sun disk. Another way you can observe this difference is if you observe moons doing this as they line up in sissy g e on

the surface of other planets. For example, you get the Curiosity rover and you turn its camera up so it looks towards the Sun. You can observe solar eclipses on Mars as the Martian moon Phobos passes in front of the Sun. Except it's not really a total eclipse, and it never could be because even when Phobos passes dead center across the Sun, it's too small to cover up the Sun. So in said, it's like a big black pupil in the middle of the Sun. As an eye, it looks like a big Google eye. I've seen it

does look like a big Google eye. It's like one of those things that did you ever like make those little Google eyed toys when you were a kid. You can buy old Google eyes at the When I was a kid, I've I've never stopped making. For a while, I was daring enough to carry around a pack of Google eyes and stick them to various signs on our local transportation uh, this public transportation system here in Atlanta. But but then I got a little scared and stop

doing it. Why do you get scared and I was just a friend like this, I just decided this is a silly thing to get in legal trouble for like I would hate to be the guy who's arrested for putting Google eyes on a on an advertisement, Like is this worth the hilarity? And it it was. It was a tough decision, but I ultimately decided it was not.

You know the name of Phobos, the Martian moon, Phobos means fear, but it apparently is not afraid of the same thing you were becauause up Google eyes the periodically make a Google I right on its parent star. Now, if you know the right equations to calculate angular diameter by distance, that's by saying, okay, if I know how big something is and how far away it is, I can calculate how many degrees of my view it's going

to take up. Or if you just have a handy online calculator that does this and I came across a few you can actually go back and resolve this to find out how much of your field of view. Various planetary objects will take up at different distances. For example, the average distance from the Earth to the Sun is about a hundred and fifty million kilometers, and the diameter of the Sun is about one point four million kilometers. It works out too that the Sun takes up about

zero point five three degrees of view. Meanwhile, the average distance from the Earth to the Moon is about three d and eight four thousand, four hundred kilometers, and the average diameter and not the average, the equatorial diameter of the Moon is three thousand, four hundred and seventy six kilometers. If you calculate that, it also takes up just a little over half of a degree of view, about zero

point five one eight and so on. Average both are about half a degree, and since degrees are usually broken down into units of sixty, argument, it's both are just over thirty arc minutes in the sky, so they can line up so that the Moon just perfectly blocks out the Sun. It's a beautiful fact about Earth that makes us special. Now here's the question, Joe, that I imagine a number of people have have pondered, is uh, like

the rarity of a solar eclipse? Because like for me, I have never witnessed a total solar eclipse, and therefore I'm very excited, like this is the first time in my life it'll be the first time in my my son's young life. And you know, I'm not sure when my next opportunity will will truly come, so I'm gonna pounce on it. But but why is it so rare if it's just tied up with the very predictable movements of of our celestial bodies. Yeah, this is an interesting question.

So if the Earth orbits the Sun onneon and the Moon makes a full orbit around the Earth roughly once a month, how come there is not a solar eclipse every single month? Think about it, right, So, if it's going around the Earth once a month, shouldn't it pass directly between the Earth and the Sun once a month. Well, it actually does this from one direction, but it doesn't

from the other direction. So the reason this doesn't happen every month is that the orbit of the Moon is not exactly flat with respect to Earth's orbit around the Sun. And we can call Earth's orbit around the Sun the solar plane. Think of that is taking place on a flat table. Now, if you're looking top down on this flat table at the Earth and the Sun, the Moon goes in an oval shaped elliptical orbit around the Earth. But if you get down and look across that table

across the plane. So that the Earth's orbit around the Sun is flat, the Moon's orbit around the Earth is going to be slightly tipped to the side, tilted just about five degrees off. So think of it like a wide brim hat, just slightly cocked to the side. And so what that means is most of the time, the Moon is not directly on that flat plane between the Earth and the Sun and just intersects that plane twice every month, once going up and once coming down north

to south ooh, and south to north. So the only time you get a solar eclipse is when these two intersections happen at the same time, you know, by coincidence. So when the Moon passes between the Earth and the Sun on the east west axis and when it just happens to be simultaneously crossing the solar plane across the north south axis, that's when you get a solar eclipse. Now that being said, obviously every solar eclipse is not a total solar eclipse. We have a few different varieties here, right,

So you've got the partial solar eclipse. This is the pac Man eclipse. Uh, the Moon partially blocks out the Sun it'll some people would say it takes a bite out of the Sun and giving it a press and appearance and a brief, sometimes undetectable dip and luminosity depending on how much of it, how much of the Moon

is crossing the Sun, based on your vantage point. And in this type of eclipse, the Moon never completely blocks out the Sun. So these happen fairly often and they're not as startling or as you know, attention getting as

a total solar eclipse. A total solar eclipse is when the Moon completely blocks out the Sun, causing darkness at day and the ability to look up at the sun disk blocked with the naked eye and see the corona around the Sun. Now, I want to modify naked eye in a minute, because there are some important precautions you'll need to take if you're going to be viewing the solar eclipse this year. Now, I do want to throw in real quick, we're not really talking about lunar eclipses

in this episode. But what's occurring there is you're seeing um that the shadow of the Earth cast upon the Moon, right, So it's going to be the opposite side effect of the solar eclipse. It's when the Moon happens to be crossing the solar plane at the same time that it's directly behind the Earth on the east west axis. Alright, so solar eclipse that we have partial, we have total. What else do we have. We've also got the annular eclipse, and this one is kind of interesting. So this is

when you would have a total eclipse. It's when the Moon does pass directly in front of the Sun from your point of view, but it never completely blocks the Sun. Instead, what happens is it leaves an always visible ring of sunlight around it. If one of these is happening, you should not look at the annular eclipse of the naked eye because a lot of the sunlight is still going

to be getting through. Now you might be thinking, wait a minute, how can that happen, because didn't we just talk about how from our perspective, the Moon and the Sun are the same size. Well, they they're about the same size on average, But those averages are just averages. So the apparent size of the Sun and the Moon can both vary depending on where they are in their orbits. In both cases, I was calculating on the base of

average distances. Uh, and so the Earth and the Moon both have elliptical orbits around their their gravitational parents rather than perfectly circular ones. When the Moon is closest to the Earth, this is called the parage, it looks bigger, and when the Moon is farthest from the Earth, of course, this is called the apoge it looks smaller. Likewise, there's a tiny amount of variation in how big the Sun looks, given whether the Earth is closest in its orbit or

farther away in its orbit. So if the Moon is at a lower apparent diameter and the Sun's at a greater apparent diameter, the Moon could fall directly in the middle of the Sun and still not block the whole thing. So you get a ring of light in the sky, and this is what's known as the annular eclipse. There's also another rare type of eclipse called the hybrid eclipse, and this this happens when the apparent diameters of the Sun and the Moon are sort of right on the

boundary of going from annular to total. So some people on the Earth will see an annular eclipse, and people in other locations we'll see a total solar eclipse. And this is when we have werewolves, right, because there, of course the hybrid of man and wolf. I mean, when else would we have werewolves. It's the prime opportunity. It's important that you point out that the solar eclipse has

these kind of supernatural connotations. We we talked in our other eclipse episode about many of the myths associated with eclipses, but there are particular myths associated with the total solar eclipses, right. Oh yeah, I mean it makes sense right that you have this this cosmic event. You know, early early people are looking up into the uh at the stars, at the sun and the moon and trying to make sense

of what's occurring there. They have myths that are that in some cases have been created to explain natural phenomena, but in other cases, you know, kind of exist on their own but then get reinterpreted in the light of natural phenomena. We've talked about this sort of interplay and varying theories of of of natural phenomena and mythology before. But the result is, yeah, you have a number of a number of monsters and monstrous creatures that are said to eat the sun or the moon, or attempt to

eat the sun or the moon. Uh. For instance, in the case of the the Indian UH entity Raju Uh, he's this decapitated head and it has said that he eats the sun, but then the sun falls back out of his next jump because he has has no body. And we talk about that myth in detail in our our Past eclipse episode, which will be linked to on the landing page for this episode is stuff to blow your mind dot com. That is such a visceral and wonderful myth. It's like it's like something you'd see in

an itchy and scratchy cartoon. Yes, I don't mean to denigrated. I mean it's just like so it's so gory. Oh yeah. And I didn't even get into the details of the decapitation where he's decapitated with this divine weapon that's kind of like the spinning weapon and crawl. So it's it's it's a pretty delightful episode. It's one of my favorite

UH eclipse myths for sure. Well, it's not a surprise that the eclipse call as people to think of the supernatural, because it's one of the most awe inspiring sites in nature. It's hard to think of something that without the aid of technology, humans can see that is so unbelievable and so alien to our day to day experience. And we're talking about the sun going dark. Uh it this is the kind of thing that ties into at least two different apocalypse smiths, both the Christian Apocalypse as well as

North Ragnarok. Yeah, it seems like a literal challenge to the established order of the cosmos night and day light and dark sun in the moon. It's completely destabilizing. So it's just no wonder that many people throughout history have reacted to it with sheer terror. Now, apart from the traffic that you may expect, we hope you will not react to this eclipse with sheer terror, but with all the wonder that's due to this fantastic demonstration of physics

and nature at work. So maybe when we come back from a quick break, we will talk about this upcoming eclipse in August of only seventeen. All right, we're back. So, Joe, I don't know do you have plans yet for the eclipse. I'm still trying to make up my mind about what I'm gonna do. I've got several options, and I'm I'm so disclosure here. Robert and I we live in Atlanta here, so we're pretty close to the line of totality, and

so Robert, I know you have some plans. Yeah, the family and I are going to drive up to the mountains and uh and seek the total eclipse. Nice. So if you live almost anywhere in the United States, you will be able to see a partial solar eclipse, which is the Moon's shadow passing over part of the Sun. But there are other chances that people are going to have to see that. Impartial solar eclipses are much easier to see because they just affect a much larger portion

of the Earth's surface. If you were within what's called the line of totality, you will get to see a total soul eclipse on Monday, August one, and that's the Moon passing straight in front of the Sun and completely blocking it out. So the line of totality is about seventy miles or about a hundred and ten kilometers wide. If you're within that line, that's where the total solar eclipse will happen. And the total eclipse will start in

northern central Oregon um at about ten fifteen am. I think they say first contact, which is when the sun very first touches the Moon. That's going to happen sometime closer to nine am Pacific time over there, but first will happen about ten fifteen am Pacific time, and it's slowly going to pass over the United States, and a line running southeast from Oregon through Idaho, Wyoming, Nebraska, Missouri, Kentucky, Tennessee, Georgia, and South Carolina, also touching small parts of a few

other states. You can look up a map online. There are a bunch of them. NASA has done one all right. Now, we've already talked about the rarity of solar eclipse, but just just how rare are they really? Well, there's sort of a misconception actually that solar eclipses are extremely rare on principle, and actually solar eclipses and lunar eclipses happen it pretty close to the same rate, if I think, if you count pennumber lunar eclipses, lunar eclipses are a

little bit more common. According to the Belgian astronomers gen Mayas, in the twentieth century, there were two hundred and twenty eight solar eclipses and two d and twenty nine lunar eclipses, So they're not actually a rare phenomenon in themselves. But what's rare is for a total solar eclipse to pass over wherever you happen to be. So, as as we discussed a minute ago, not all solar eclipses are total eclipses.

Some are partial or annular. And solar eclipses happen all the time, but you probably won't get many chances in your life to see one unless you have the resources to travel around the globe and chase these lines of totality wherever they happen to be falling. All right, so let's get let's get down to brass tacks here. Okay, driving up to uh, you know, the line of totality is one thing, right, you know, maybe you're close to it, maybe you're far away, but with enough planning you can

get there staring at the sun the whole way. Because that's the thing that what does one need to protect themselves while staring at the sign, while staring up even at a sun that is about to be obscured, uh by the moon. Uh? You know what, we have all these special glasses that are suddenly on the market. I mean, you can even buy them. I saw them at lows. Uh, why are these necessary? I was talking to a good friend of ours and and he was like, I mean

he's he's a cautious dude. But he was like, yeah, I think you think you can probably look at the eclipse and you'll be all right. Just the same as you should never look directly at the sun without proper eye protection. You should never look directly at part of the sun without proper eye protection. And if you're thinking, says you, you know you big buzz kill. Uh maybe you think people have been looking at eclipses for thousands

of years it is, without special goggles. And they were fine, No, really, I've been reading about this. Don't look at the sun or even part of the sun. Here's what could happen. Uh. First of all, there if you want to hear it directly from an expert, there's a very quick interview that news Week did with Dr Christopher Quinn, who's the president of the American Optimetric Association, about what kinds of injuries

result from looking at the sun without protection. You can go check that out if you want, but I'll give you the basic rundown. One possibility is photocarrotitis. So photocarrotitis is usually described as a sunburn of the eye. It's not pleasant sounding at all. Yeah yeah, and you can't

really rub alo on your eye volcan now. So it's when UV radiation ultra violet radiation causes damage to the cornea and the conjunctiva, which are the outer surfaces of the eyeball, and symptoms include pain, a feeling of having grit or another foreign body in the eye. Red eye is swelling, sensitivity to light, excessive tearing, and sometimes temporary

loss of vision. So welding arcs produce UV radiation, and this is what can happen to a lot of welders if they don't use safety goggles or welding glass when they're doing their work. Uh. The photocarrotitis is also sometimes referred to as snow blindness. I know you've heard of

snowboy in this. The reason it's linked to snow is that snow covered ground tends to reflect a much greater percent of UV radiation than most other natural surfaces like grass or soil usually reflect only about ten percent of the UV rays coming from above. Snow can reflect almost all of it, nearly doubling your UV exposure, So in snowy environments it's important to wear eye protection. But hey, here we're only talking about the reflected or ambient rays.

If you're looking at an eclipse, you're looking directly at the sun, and if you do that, even for a very short time, you are inviting sunburn of the eye. So if you think you've got photocarreti is you should probably see a doctor. But the good news is this will usually heal on its own in a few days if you remove the source of injury and give your eyes some rest. However, there are other possible injuries that are more serious. How about photic retina pathy. I'm not

sure I've heard of this one. This sounds painful as well well. This occurs when exposure to direct intense light, such as sunlight, lasers, or welding arc light causes phototoxic damage to the retina itself. And this is not going to be on the outer layer of the eye. Like we mentioned with photocaratitis. The retina is the projector screen

of the eye. It's the It's the layer of the rods and cones, the light sensitive cells that detect incoming information and transmit it to the brain, and exposure to intense light in these cells can cause injury through two main mechanisms. A minor mechanism is going to be thermal burn,

like heat burn burn through the heating of tissue. And this generally only happens when you're looking at the sun through a telescope or a magnifying lens of some kind that concentrates the radiation, sort of like you know, you knew the kid who burned dance with a magnifying glass, except the answer your own eyes. So we're talking about it, uh, in our first case, we're talking about outer eye damage. Now we're talking about inner eye damage, right, But that

that's the minor cause. The major cause of photic retina pathy would actually be photochemical toxicity, and this happens when exposure to excess light causes chemical reactions in the retinal receptor cells that damage the retina and reduce its ability to detect a light. This damage can be permanent or temporary, It just depends on the case. So you might be wondering how often does this kind of thing happen to

eclipse viewers. A report in the British Medical Journal assess the aftermath of a recent solar eclipse that was just visible in the UK, and so the author seemed to think that the campaign of public safety warnings ahead of the eclipse mostly succeeded in preventing people from looking at it with the naked eye. About a week after the eclipse, he could find fourteen reported cases of retinal injury in

British hospitals. Many more people called emergency helplines are presented at hospitals with fear of injury, but most were false alarms. And I got to read one quote quote one overseas tourists who sought help in Glasgow said that she was worried because she had not been exposed to the Scottish before. Another Glasgow patient was concerned that her face had been turned yellow by the eclipse, but was told that her

longstanding liver problem was the culprit. Oh man, let's get both of those cases are interesting insights into the like the self analyzing, self diagnosing a tendencies that we have. Right, So, not that many people had permanent eye damage, but he's attributing that to the fact that they had had a massive public information campaign saying don't look at this thing without eye protection. So and eye protection, by the way,

does not mean sunglasses. This is crucial. Now before we get into health safety information, we do have to do the disclaimer right. We are not optimologists or any other kind of physicians or I safety experts. Will do our best to brief you on eclipse viewing safety, but you should check with other sources, including the American Astronomical Society, NASA and the American Academy of Ophthalmology and other experts of course, And if you interpret anything we say to

be in conflict with what they say, obviously go with them. Also, if there's any ambiguity about when and under what circumstances you can or should look at the sun, just don't

look at the sun. So here's the rundown. If you are within the line of totality where the Sun is completely blocked out by the Moon, it is safe to look at the eclipse with the naked eye, but only for the brief time when the Sun is completely blocked and this is only gonna last a couple of minutes or so, depending on where you are along the line.

If you are not directly within the line of totality, if you're in one of those partial eclipse areas, or if you want to look directly at the eclipse during its partial phases, while the Moon is covering up the Sun, or while the Moon is moving away from the Sun. Uh, anytime the disc is partially covered, you need to look through a verified safety filter. Regular sunglasses are no good and not safe. NASA has actually issued guidelines on what

is safe. So you've got a few options here. One is what you mentioned, Robert, eclipse glasses, right, do you already have yours? We have ordered them. Okay, you've got to get eclipse glasses from a reputable manufacturer. These look like regular three D glasses sort of there like a cardboard frame with a partially reflective surface over the lenses. If you have these, one way you can test them out and make sure they're legit is just put them on without looking at the sun or anything, and just

look around. You shouldn't be able to see any thing. Should be completely opaque pretty much. But if you look up at the sun, you you'll be able to see that, but pretty much anything else is going to be blocked out. But anyway, you should make sure you get your eclipse glasses from a reputable vendor who is not trying to sell you actual three D glasses. They're going to burn your eyes out. I got mine from a company called

American Paper Optics. The official safety standard is i S O one to three one two dash two and a good eclipse glasses will have this code on them if you're buying from another company. Actually, the American Astronomical Society has a web page where they list known manufacturers of safe, legitimate solar viewing glasses, and we will link to that page that lists legitimate companies on the landing page for

this episode. Another thing is maybe you have some eclipse glasses that you bought for like I don't know, and eclipse ten years ago or something, and you've got them lying around the house and you want to pull them out and say I'll use these again. Check them. Damaged to eclipse glass can hurt you. So you've got to make sure that there are no holes, no terrors in your glasses or anything like that before looking at the sun. You probably just want to invest in some new ones,

but also a few other options. Uh. You of course can use an indirect method like a pinhole camera or something like that that's probably gonna be a little bit less spectacular. But if you want to see how the movement of the Moon across the sun disc is progressing.

You can, for example, look at shadows on the ground, or you can use a pinhole camera or something like that that doesn't have you looking directly at the Sun. Another option, if you or anyone you know is a welder, a mask or goggles with industry standard welding glass will be safe, but NASA specifies that it should be a number fourteen welding glass or darker. And if you don't know whether your welding glass is dark enough, don't risk

your eyes to find out by some eclipse glasses. Finally, there are also telescopes with built in solar filters like they're made specially for looking at the Sun and solar astronomy. You can look these up online. They're they're pretty interesting. One thing, though, is don't try to just wear regular eclipse classes when looking through a regular telescope, because the telescope may well concentrate what you're looking at and then project that and make it too strong for your eclipse

glasses to filter properly. All right, now, if I have none of these things, and I and I wait till the last minute, and I go to the store and they're out of eclipse glasses, and everybody who has eclipse glasses you're planning to wear them. H what's what's my and I don't want to go with the with any of these other techniques. What are my options? Well, you can also check with your local library. That's a good bet. A lot of libraries I've seen have eclipse viewing glasses

that they will give you. They they've had programs to distribute these around the country. So if you you're you're down to the wire and you still need some check with the library. They may have them. All right, Well, that note, we're gonna take one more break, and when we come back, we're gonna point out some things to to look for during the eclipse, and if you have already seen it and you're listening to this after the fact,

these will be things you can reminisce on. And we'll also have some sort of a frequently asked questions section here with some some additional concerns you might have about the eclipse, and we'll try to answer those as well. All Right, we're back. Okay, So, assuming you have the correct eye protection, assuming you're in the correct geographical location, within the line of tortality and assuming the weather is

being cooperative. Um, what is one going to see? Well, the first thing you'll probably see is what's known as first contact, and this is when the moon very first begins to cross in front of the Sun, partially casting its pennumberal shadow. And again at this stage, if you're looking at the Sun, you need to be looking through a safe filter. So everything I'm gonna say going forward, unless I indicate otherwise, you need to have your your

safety filters on. Over the next hour or so, the moon is just going to very slowly continue to cover more and more of the Sun. It will go slow so you can hang out, you can look at it occasionally and see what it's doing. But this is another reason for the eye protection, because there's gonna be if you did not have eye protection, this would be a lot of looking up at the Sun. Like even in quick gazes, it's going to quick glances, it's going to

add up. I mean, I'm not an eyehealth expert. Based on I've I've taken my solar eclipse glasses and looked at the sun. Um, I probably wouldn't recommend even if you have the safety glasses on just staring at the sun for hours. I don't know. Maybe they'd be okay, but it just it doesn't seem like a great idea. I mean, it probably probably confine it to uh to as much as you need to look at the sun for the eclipse purposes. Okay, when is it going to

actually start, like changing the way that our world is illuminated? Yeah, about maybe three quarters into the covering of the sun. Once about three quarters of the way there, you're probably gonna notice lights start to change colors, and you will notice differences in shadow depth. So you should not just look up, but look down and look around the world. Notice that you may be casting a different kind of shadow. Some contrast may be heightened in the shadow you cast

versus the general atmosphere. Um, you you may notice some strange colors along the horizon and in the sky. So this is a time to check out what's going on all around you, not just up in the sun. Now. Also you can pay attention to how the world feels. So as the moon moves in for its final approach to totality, you're probably gonna start to notice changes in temperature. Right, the temperature can drop, so winds may be affected as a rapidly cooling strip of land will cause sudden pressure

differentials that could draw winds here and there. Yeah, because the cycle of night and day has a tremendous effect on the movement of air in our atmosphere. Absolutely, and then the shadow comes. So here's what they say is one of the coolest parts. As the totality approaches, look to the west. Figure out this is a good thing to do. As soon as you get to wherever you're going to be to view the eclipse. Get your bearings.

So nowhere north, south, east, and west are and as the eclipse is approaching, pay attention to the westerly direction, so look to the west, especially if you have a good vantage point, you may be able to see the moon's shadow slowly sweeping across the land like this tide of evil magic. Also, look at any clouds in the sky to the west of you. You should be able to watch the Umbrell shadow of the moon pouring over

the clouds as it travels west to east. Now, the Umbrell shadow, I should have mentioned earlier, but you generally have. You've got the Pinnumbrell shadow and the Umbrell shadow. The Pinnumbrell shadow is is very wide but not nearly as dark,

and the Umbrell shadow is the center shadow line. It is the very much smaller but much darker center show at oh now, the Sun is going to continue to shrink more and more behind the Moon's shadow, until almost all that's left is this tiny crescent on one side and the visible corona, which is going to be the whispy, dancing outer atmosphere of the Sun, and that will be on the other side from the crescent. In the last few seconds before totality, you still got your filters on,

but you'll get to see something really cool called Bailey's beads. Now. This is named after the English astronomer Francis Bailey, who described the cause of this in a letter to the Royal Astronomical Society in eighty six. And what it will be is you'll see the Sun, the bright sun disk behind the Moon, and these beads will appear as sort of bright jewels of light dotting the edges of the

black moon disc. What are they? Their topography In places where the Moon's surface right along the visible edge of the Moon dips into valleys um, the last rays of light are going to shine through those valleys and low topographical areas before the sun is completely covered. Uh. And according to so, a lot of what I've been describing here came from some really helpful materials prepared by the American Astronomical Society. They recommend that when you see the

very last Bailey bead, the very only one remains. Uh, this is the diamond ring, which is when it's it's about time to get ready to take your filters off. So the last diamond ring is there, the Bailey's beads are down to one, and then you can take your filters off and it's totality. The sun will be completely

hidden and only the corona is there. Uh. So you can watch this part with the naked eye, but always be conscious while this is going on that you will need to replace your filters as soon as the moon moves back out on the other side and the totality is over. Depending on where you are, it's probably only going to be between one in three minutes. Yeah, and

now they daunting. Part of the for me as a parent is that I've I've got to take care of my own glasses hearing all this, but I also have to make sure my son is putting his back on or and or taking them off at the right moment. So, um, I feel for anyone who's you know, handling a number of children, particularly small children, during this encounter. Yeah, I'm not sure what the best way to do that is.

Maybe one thing would be to research ahead of time, because their NASA has maps that can help you figure

this out. Uh, there are maps that will show you about how long totality will last given where you are viewing from, and you can use that to maybe set a timer ahead of time, if you bring a little kitchen timer with you or something like that to set it, I don't know, fifteen seconds short of when totality is over so you can start getting the filters back on, or just I'm thinking I'll just throw a heavy blanket over its head at that point, like it's done, it's over,

go under here. Well, I mean, if you've seen, if you've seen the approach with your filters on, and then you've seen the the toe total eclipse with the naked eye, maybe I don't know, maybe it's less important to see

the recession of the moon. I don't know. Well, you know, sometimes there's an after credit sequence, right, but you know, I think a lot of these details are are key, especially you know about how the topography of the moon coming into play, because it's easy to think of this as it's a solar eclipse, it's a solar affair, but it's really just as much about the moon, if not more about you know, so, uh so, don't forget the

Moon while you're observing this. Well, it's it's fascinating about the Moon in the same way that the lunar eclipse is really about the Earth. Yeah, and the Earth gets virtually no credit. Right. Well, I mean, here's a cool fact about lunar eclipse. I know this is a solar solar eclipse episode. When you think about a lunar eclipse, what happens generally is that you go in for a total lunar eclipse and the moon turns red. Why does the moon turn red? How come it doesn't just get

completely blackened? Because what's happening when you go in for a lunar eclipse and the Earth blocks the sunlight from hitting the Moon is that you still have some sunlight hitting the moon, and it's the sunlight that filters diagonally through the Earth's atmosphere. And what happens is that when you you know, you notice when you see a sunset, the sun is going down, that's when you start to

see red colors in the sky. And that's generally the one of the rare moments when you can look towards the sun and view it without because you're you're ultimately viewing it through multiple atmospheres where the sun is directly above you in the new sky. That's there's like one atmosphere is worth of filtration taking place. Even when the

sun is setting. You should not look to me, don't don't look at it, but it's more visible, it's more bearable, right kind of you know, glancing way, it's easier to do what you shouldn't do at sunset. But you see all those red colors because yeah, it's the red wavelengths, the longer wavelengths of red light that can travel farther through that greater distance in the atmosphere that gets scattered

less um, and so they travel farther. You see those red colors at sunset, and it's for the same reason that sun traveling. I think earlier I said diagonally, I guess I should have said laterally. Maybe sun traveling laterally through the Earth's atmosphere and still splashing on the Moon. That you see those red colors. That's the red light that survives earth atmosphere to still shine through and around onto the Moon. But hey, let's get back to the

solar eclipse. So the solar eclipse is going on. You've hit totality. This is where you are. So the Sun is now completely hidden and only the corona remains, and the corona is going to be the visible outer atmosphere of the Sun. The Sun has an atmosphere like the

Earth does. It's a layer of plasma, hot gas, and magnetic fields extending out into space from the surface of the Sun. If you can see it, especially through an appropriate telescope, you'll probably notice feathery wisps reaching out into space. You might also see some loop shaped structures peeling off of the solar limb. That's gonna be the edge of

the solar silhouette. And these are gigantic tracts of charged particles flowing in loop shape magnetic fields projected by the Sun. The Sun's corona is actually an interesting subject that astronomers are still learning about. So the heated matter in the corona is millions of times less dense than the surface of the Sun, but it's also hundreds of times hotter. A counterintuitive mystery of solar behavior, but that we really

don't fully understand. The explanation for yet another fact. As the plasma in the corona is ejected out into space, where does it go. It becomes the solar wind, which you've probably heard about in other context, maybe powering our future solar sales, or stripping away the ancient atmosphere of Mars off into space and leaving it the cold, dry

rocket is today. So when you look at the eclipse, whether through an appropriate telescope or with the naked eye, look around the edges and pay attention to what you see. What's what's the shape of the corona? What are the contours? Can you see any interesting prominences or ejections? And also, don't just look at the sun. Look at the world around you, look at what's going on on Earth when the Sun is hidden. You might you might notice some other strange changes in color and temperature. I bet it

would be cool. If you're a photographer. It's obviously going to be really cool to get as many pictures of the sky as you can, but you might also want to get a picture of what everybody around you is doing. Yeah, well yes, uh, I mean you don't want to miss the eclipse because you were taking pictures of everybody. But maybe that's the way you should set it on a tripod and put a time or there. I guess so.

But then again, uh, photographers, and I'm married to a photographer, so I can I can say that they do have a tendency to take photos during pivotal events. You know, I I am not a photographer person. And what I mean not just that I'm not a professional photographer, but I noticed there are basically two groups of people. People who, when they're experiencing something they anticipate as being memorable, immediately want to take pictures of it, and the people who

don't wanted to take pictures of it. I'm in the latter camp, but I totally appreciate the people who are in the former camp. I think it's just different ways of participating with the anticipation of memory. Well, I look at it this way, Like with me, I do try to focus more on just experiencing the thing, but not being a photographer. My art form is not about capturing the moment like that. Like, if I'm going to write something about about a really cool event, well then it

depends on me experiencing it. Whereas a photographer like that, their craft, their art is capturing what is happening, So of course they have to be there. They have to they have to be the one taking pictures during the wedding ceremony because because they are capturing it, it's the it's dependent upon them not experiencing it. You know, the photographer wants to wants to make a record of the truth. The writer prepares themselves to lie in the future. That's true.

That's true. Though I guess you could say that the photographer is preparing to lie depending on how many filters and how much editing is going on afterwards. That's a good point. Well, anyway, I shouldn't tell you what to look at. Hey, when the when the eclipse is going on, you look at whatever you want to look at. Joe's not gonna tell you how what's a look at. He's just gonna tell you how exactly to look at it,

what precautions to say? Which is responsible? Now, like I said, it might be helpful to have some kind of timer or just to be cognizant of about how long you've been looking at the eclipse. Though I've read reports from people who have viewed total solar eclipses that you can kind of have a lost time experience, like you've been looking at this thing for two and a half minutes and it felt like a few seconds. It's just gone

before you realize. But anyway, if you do have some way of anticipating that it needs to be time to get get your solar filters ready again. Once you see the diamond ring quote emerge on the opposite side of the sun, once the Bailey's beads start to come back, totality is over. And if you want to keep watching,

that's when you need your filters back on immediately. Uh, And you should try to get them on very fast because one of the things I was looking at in in you know, these optical injuries from sunlight is the length of exposure is not necessarily like you don't have to be staring at the sun for a long time

to get injured. Now. Of course, at this point you're gonna end up watching the reverse, right, You're gonna watch the the moon reveal the Sun. And I think it's it's important to to think about this not as like the end of the eclipse so much is like the rebirth of the sun. Right that you're still watching something amazing.

You're watching, You're watching the type of sunrise that that only occurs, uh, right after a solar eclipse, right after a total solar eclipse, you're watching the sun pour out of the severed neck of the god Ra who yeah, exactly for the demon Ra who well, technically an Osherra. So it's yeah, it doesn't necessarily translate one it but hey, we understand that probably lots of you out there aren't going to be able to view this total solar eclipse,

and that's understandable. It's it's gonna be cutting right through the middle of the United States. But lots of you out there are not even in the United States. We know lots of you are living in in Europe or Asia, South America, Africa. We we've got friends out there all over the world. So, uh, you can actually anticipate upcoming solar eclipses that might be coming to your area by checking out NASA's website. For one thing, they've got a

really great future eclipses calendar. Yeah, and actually the Wikipedia is not bad as well. If you just want to see a quick rundown of upcoming solar eclipse and total solar eclipse, I mean definitely linked that on the landing page. That's stuff to blow your mind dot com. Now, the short answer is that, luckily, luckily for you, there's a total solar eclipse every year or two. Okay, but you'll need to be willing to travel anywhere in the world

to catch them, all right. I mean, as we said, it's not that solar eclipses are rare, it's just that they affect such a small portion of the surface of the Earth. It's very rare to have one happened near you. Right. So, for instance, there'll be another solar eclipse July second, two thousand nineteen, but if you want to see it, you need to start saving up for a trip to Argentina

or Chile. Now, if you are in the United States but you can't see this one this year, there is gonna be another total solar eclipse passing through the United States in that's the ways off and well seven years from now. But yeah, I mean just stick around. Yeah, I can't even it's it's it's ridiculously far in the future, and yet not so far in the future. Okay. Frequently ask questions with regard to eclipses, How dark will it get, Joe, that's a good question. It's gonna be pitch black and

you won't even be able to see your own hands. No, that's not I've heard it described as sort of like a sudden twilight about thirty minutes to an hour after sunset. But do not go into this expecting pitch black, because you will be disappointed. I guess right, all right. Will the temperature drop? Yes? Generally that that usually happens during a total solar eclipse. The temperature usually drops by an average about ten degrees fahrenheit or about five degrees celsius

within the line of totality. Not so for the line of partial eclipse. Maybe that's not a line the huge swath of partial eclipse, and there have been cases where it dropped much more. The change should be similar to a sudden transition between the temperature of midday in the

temperature after sunset. Uh. There was one article I was reading that that told a story about how during a total solar eclipse in the in the United States in eighteen thirty four, temperature was recorded as dropping as much as twenty eight degrees fahrenheit from seventy eight degrees fahrenheit to fifty degrees fahrenheit, which is I guess that would also be dropping about fifteen degrees celsius. So who knows what's going to happen. But but yeah, maybe maybe it'll

get very chilly. You might want to bring a jacket, all right now. You also might be bringing a pet with you. I know, Joe, you you have a dog, Your dog, Charlie is is if you do travel, are you taking Charlie as well? We almost always take Charlie as well. If we can get away with taking him,

we'll take him. All right. Well this, you know, a lot of people have asked about this, and I see I actually see this question popping up online, and sometimes the answers are not that great or not that that factual. I'm gonna be straightforward. I've seen a lot of what looks like bs about people saying that animals go berserk during an eclipse. I have not seen anything that looks like a good, reputable source claiming that it's more just

kind of like dumb looking websites. Now, there are some reports here and they're going back throughout history of like individual observations of animals acting a bit unusual for daytime behavior. That might happen. They might make different sounds, they might they might become more visible or less visible. But what I do not predict is ecological pandemonium and widespread animal

freak outs. Based on what I've looked at and the science I've liked that, Uh, there's nothing magic is going to happen in regard to your pet during the solar eclipse. So animals simply tend to react to the darkness as if it were occurring during the typical cycle. So scientists have that have observed this in the vertical migration of zooplankton in the ocean due to lunar eclipses, as well as the countless larger animals when it comes to solar eclipses.

So you know, likelihood, it's possible you might hear some twilight animal noises uh during the eclipse, but that's gonna be the extent of it. Dogs are not going to turn into cats. Cats are not going to turn into dogs. Uh, that's gonna be the the extent. So hamsters might turn into crayfish. Well, yes, but but for reasons unrelated to the solar eclips Roughly speaking, diurnal animals react as though night we're approaching, and this is this is demonstrated and

expedited roosting and betting behavior. In contrast animals that are normally active at night. Uh. Nocturnal animals like bats, they may show the reverse pattern, emerging in the into the open as the sky darkens during an eclipse. So actually I would be very interested if anyone you know, can look away from the eclipse long enough to notice what animals are doing, If you see any bats come out,

I would love to hear about that. If there's any any any sightings of nocturnal animals at least stirring, does club life get going? I will will come back to that. I have I have a question too about that myself. Now, as you mentioned some websites they are talking about, oh, there's gonna be a full fledged freak out of pets in the eclipse uh. And I don't think that is

going to happen. But one thing, one point that has been made is that if you were hanging out with a lot of people during the eclipse, sometimes people get high spirited, They make a lot of noise, they kind of celebrate because it is an amazing thing to see. If your pet dog, for instance, or certainly your pet cat, which you for some reason brought into the wilderness of view and eclipse, if they if they kind of freak out when people are freaking out, well then that might

be a problem. Or if you just got your cat in that cardboard box, people used to take it to the vet. Yes, so you know, ultimately, you know your pet. You know how your pet reacts to issues, you know, unrelated to to the total eclipse of the sun. Uh, you know, you can judge this best, but there's not gonna be any kind of magical reaction, uh, you know in your pet caused by the sun. They're not going

to be wild animals. They're gonna be behaving in a way that's going to be you know, immediately noticeable to you most likely. All right now, but here's a question that arises regarding not animals, but but human technology and other kind of zoo Is this going to cause car accidents? This, of course, I guess, is assuming that they're going to be people driving around not expecting a cellar eclipse, and then it just occurs and people you know, drive off

the road and run into each other. It might cause car accidents, but I think much more likely is that it will cause extreme traffic congestion. They're gonna be people from everywhere descending on a strip of the United States. It's only about seventy miles or ten kilometers wide, and mostly they're going to be getting there by roads. So seriously, if you are going to be in the line of totality, you should expect the traffic situation to go plaid. It's

it's gonna be crazy. I can fully predict now, I've just seen a few examples. There is actually a good house Stuff Works article about this about how the upcoming eclipse will impact transportation. Oregon state officials are expecting an influx of more than a million people into the line of totality Idaho. Idaho is expecting half a million visitors. The population of Idaho is only about one point seven

million people. The state's population is going to increase by almost one third in the in the line of totality. Missouri officials expect more than a million people. The city of Columbia, South Carolina, is expected to temporarily more than double in population. So if you're traveling for the eclipse. First of all, this might be obvious, but I feel I should say it. Don't try to look at the eclipse while you're driving or while the car is moving. Pick out a viewing spot ahead of time, and get

there early, real early. Also, don't pull over on the side of a highway or a freeway to watch. This is just going to further congest traffic and it may block emergency vehicles that need to get somewhere. Don't do it. Instead, plan ahead, figure out where you're going, pick out a place or a place to park, or stay ahead of time and get their early. Uh. And also expect to have to wait a long time to get home. I imagine the highways are probably going to be clogged up.

If if you're gonna be trying to get back home wherever you came from that day, it might be a problem. Yeah. I think it was Georgia Department of Transportation that was warning against the becoming a I think the quote was an eclipse refugee where you the idea. I guess as you set out without a real plan in mind, and either you get bogged down in traffic or you are expecting to find room and board in the line of totality and you cannot find it, and then you're reduced to,

you know, sleeping in your car or something. So yeah, plan ahead, take supplies, figure out where you're gonna go ahead of time, and a place where you can park your car if you're going by car. And bear in mind that if you're hoping to perform some you know, sacred pagan ritual uh during the eclipse. Uh, you know, make sure you have space set aside. Right, don't do that in the middle of the highway. Don't have enough problems,

you know. Do you know? We didn't actually prepare too much for a discussion of religious right related to eclipse. But if i'm if I'm not mistaken, I believe there are a particular Islamic prayers that or prayer rituals that take place during a solar eclipse. Hadn't heard that, but I know we have a few uh Islamic listeners out there. Maybe they can provide some more details about that, because in general, I would love to hear from anybody out

there regarding their experience with this eclipse. Oh yeah, definitely, would you do how did you do it? I know, I know in recent decades, whenever there's been a good eclipse, like, the Pagans come out in full force, for they eat this stuff up. Also, are you a pagan? Yeah, so we want to hear what you're doing. Okay, what other additional questions do we have here? Show Well, uh, here's kind of a bummer one. But what if it's really cloudy? Then? Uh,

then we have some bad news for you. Yeah, surely, no getting around that is. Yeah, I mean depends on how you know what kind of cloud cover we're talking, but that's generally going to be bad news. But let's not try to We're not going to think about that. We're not gonna focus on the possibility of clouds. One thing is if you are looking at the weather forecasts, say right now, the day you're the day this episode comes out, and you're like, oh no, it looks like

it's going to be cloudy. Don't lose hope yet, because weather forecast that far out, you know, are not at their peak accuracy. Keep checking the weather forecast, says the day gets closer and closer each day, it's going to get more and more accurate, right, and maybe hey, if the forecast is clouding, maybe that will cut down on some of the other individuals planning to be there, be there, and you'll be able to drive there faster. All right, what else do we have question wise? I see we

have a question about the purge. Oh yeah, will purge laws really apply during solar eclips No, all all laws are federal, state, local are still going to apply. However, in addition to traffic concerns, there are local concerns. In certain eclipse hotspots. You're gonna you're gonna have, you know, this huge increase in visitors, like you say, and doubling the populations, and some of these such these travelers are

gonna be international travelers as well. So there's gonna be this possibility for more crime, more misunderstanding just by virtually there just being that many more people around, right, Possibly, yeah, I mean, just you're gonna have more fender benders. Potentially, you're gonna have more people bumping into each other, just

more people being around other people. Here, here's some good eclipse advice that may be hard to abide because it's easy to say, chill out, you know, just set your day aside, if if you're if you're able to take off work and all that to to do your eclipse viewing. Just accept that there's going to be some delays, that they're going to be crowds, that there's gonna be a traffic. Just make that part of your plan, and when it happens, you'll be ready for it and you're not gonna get

frustrated and upset. All right. I have one final question here, and this is one I don't really have a good answer for. Wait, let me guess what it is. Okay, So, since so many people think that the eclipse is going to be like the end of the world, have any previous eclipse has been the end of time? Um? No, unless I guess if you died during an eclipse, then it would technically be for you the end of time. But I I don't think I ran across any examples

of that happening, So you're probably good, you know. I mean, the timing would have to be particularly cruel for that to or perfect for that to take place. I mean, if you've got to go whine I during an eclipse. Now that's one question. But but one question that I'm legitimately wondering about a little bit. Is it legally night during a solar clips we talked about it's not gonna be completely dark, but it's not really day. I wonder are there any actual weird legal shenanigans out there that

someone could potentially exploit. What would that affect you mean, like, if there's like a law that says, like you have to drive with your headlights on at night or something like that. Yeah, or like it's it's legal to it's only legal to sell beer in a certain county after dusk, you know, things of that nature. I guess the problem is that the eclipse is not going to last long

enough for anyone to explod it. To exploit it, you want to spend your your eclipse, the one moment of time you might have to look at this beautiful phenomenon. You're gonna spend the store getting a case of beer. Yeah, I guess, you know, or um, you know, or I guess it could be a situation where, Okay, there's a there's a state law that says during the day, you can only air episodes of Baywatch, and you can only

air episodes of Baywatch after dark. After dark? Is that this would allow you to air at least, you know, a couple of minutes of a Baywatch after Dark episode. Now, I wonder if anybody out there is marketing special eclipse themed products. I was thinking, beer, are they making like a bud Eclipse that's like a new version of Bud Light that have something? I mean, it sounds like a perfect tie in, right, Like here's the beer you drink

during the solar eclipse. Get it now? Uh, you know, and and love it for you know three minut We have to issue so many warnings here. Please don't take that as us encouraging irresponsible drinking during the eclipse, especially if you're going to be doing any of the drivings. Yeah, please, please,

please do a responsible eclipse viewing. I want to say in there's some sort of OREO thing getting there, an eclipse oreo or it seems like there is some sort of commercial tie in now that I think about it, I know Taquda Banana has been doing these bizarre eclipse commercials where they're suggesting that the sun will briefly become

a banana as the moon is moving in on its territory. Well, I'm very pro banana, but it does seem like a stretched by and the banana is the official eclipse the snack item, all right, so there you have it, that the basics for the eclipse, the upcoming eclipse, or perhaps the eclipse you just saw. Hopefully we've provided you a little more insight and maybe even a little more preparation.

And hey, if you are currently stuck in an automobile traveling to or from the eclipse and you're thinking yourself, we'll have all this, all this time in front of me. What are some more podcast episodes I can listen to related to the to the subject matter here? Well, I'm glad you asked. We have the episode Gazing into the Eclipse that we already mentioned. Uh, that gets into some of the myths in greater depth. Hey, and not too long ago, I guess maybe a year ago or so.

We also did an episode on ritual regicide, the human sacrifice of kings and king figures. And one of the things we talked about in that episode was the the eclipse King of ancient Babylon ancient Assyria, where you would have an eclipse that was and there was an ill omen for the king and you might have to put in another king to absorb that curse. Right. So hey, there you go to great episodes that you can pull up as well, or have whoever is not driving pulled up.

You can find those on the landing page for this episode. It's Stuff to Blow Your Mind dot com. That's where you'll find all the podcast episodes. You'll also find, of course, the podcast anywhere you get your podcast. So we're on what Apple Podcasts, We're on Spotify, Google Play, Google Play, you name it. We're we're out there. You can you can listen to all the episodes. And hey, we're also on social media. We're on Instagram, We're on Tumbler, we're

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on this and thousands of other topics. Does it how stuff works dot Com A lot of the fourt