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Rainbows: Delighting humanity since forever · Stuff You Should Know

• 0:01
  Speaker 1: Welcome to you stuff you should know from house stuff
• 0:04
  Speaker 1: Works dot com. Hey, and welcome to the podcast. I'm
• 0:12
  Speaker 1: Josh Clark with Charles W. Chuck Bryant and Jerry Rowland.
• 0:16
  Speaker 1: Have we ever said Jerry's last night? I don't think so.
• 0:20
  Speaker 1: Well we have now it's out there. It's on the internet.
• 0:22
  Speaker 1: Even someone really updated our Wikipedia page if you look lately.
• 0:26
  Speaker 1: It's robust that even says, uh, their producer Jerry Jerome Rowland.
• 0:32
  Speaker 1: How did they know that? I guess I've said it
• 0:34
  Speaker 1: on the podcast before. I am sure that you have.
• 0:37
  Speaker 1: So how are you doing? I'm great man, rainbows, As
• 0:42
  Speaker 1: the author points out, they've inspired countless fairytale songs and legends. Man,
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  Speaker 1: I love rainbows. I think rainbows are just fantastic. They're
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  Speaker 1: probably the greatest graphic design of all time. I just
• 0:53
  Speaker 1: think rainbows are great. Well, it is funny too when
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  Speaker 1: you read the different articles how people it's kind of
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  Speaker 1: corny when they talk about how they delight and astound.
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  Speaker 1: But darn it, when you see a rainbow, even as
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  Speaker 1: a jaded, cynical adult, I can I there's no way
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  Speaker 1: you can't look and just go, oh, that's pretty neat. Yeah,
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  Speaker 1: at the very least you'll go, oh, a rainbow. If
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  Speaker 1: somebody says, hey, there's a rainbow over there, you're going
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  Speaker 1: to look up. I don't care. And if you doubt,
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  Speaker 1: if you doubt a rainbow's ability to astound adults, all
• 1:24
  Speaker 1: you have to do is look up Yosemite Bears double
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  Speaker 1: Rainbow video, which I watched today. It's pretty pretty great stuff.
• 1:32
  Speaker 1: All bear vesque is what does it mean? I know
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  Speaker 1: what it means. You're on pot. You know. Next time
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  Speaker 1: someone does to see a rainbow and say that, I'm
• 1:44
  Speaker 1: gonna test everything and just say so now I'm gonna look,
• 1:49
  Speaker 1: all right, Let's see if they just think I'm dead inside.
• 1:51
  Speaker 1: Let's see what happens. I'm curious to see whether you
• 1:54
  Speaker 1: can not look. Of course I look, um, so chuck
• 1:59
  Speaker 1: that we're not the first to be delighted and amused
• 2:01
  Speaker 1: by rainbows. Several years, decades at least, they've been around forever.
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  Speaker 1: There there is a lot of mythology surrounding them, because
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  Speaker 1: you know, they're unusual. They don't happen every day, and well,
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  Speaker 1: I guess they depends on where you live, but it's
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  Speaker 1: not necessarily in a normal occurrence. No, I found that um.
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  Speaker 1: The philosopher Descartes renee Decarte was the first to describe
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  Speaker 1: kind of the modern accurate theory in six seven. Oh yeah,
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  Speaker 1: he's the first one. It's like, hey, wait a minute,
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  Speaker 1: there's some refraction and going on here, right, Well, most
• 2:38
  Speaker 1: people usually associate that with Newton. Yeah, well he's the
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  Speaker 1: first one to describe the spectrum, right he was. And
• 2:44
  Speaker 1: apparently I saw this cool video by Philip Ball on
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  Speaker 1: the Atlantic Um that basically said that Newton just made
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  Speaker 1: up the roy G biv um spectrum. What do you mean?
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  Speaker 1: So the the red, orange, yellow, green, blue, indigo, violet
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  Speaker 1: is Newton's interpretation of the rainbow. Before that, all sorts
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  Speaker 1: of different cultures had different ideas of what made up
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  Speaker 1: a rainbow, how many colors there were, what the colors were, um,
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  Speaker 1: and our interpretation of the rainbow spectrum is a Newtonian invention.
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  Speaker 1: And a lot of people say it's not seven, it's
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  Speaker 1: actually six indigo, not really bare Newton. And apparently Newton
• 3:30
  Speaker 1: was trying to shoehorn the rainbow spectrum into the musical octave.
• 3:35
  Speaker 1: So he's he tried. He's trying to shoehorn music which
• 3:40
  Speaker 1: has sound wavelengths with light which has wavelengths and making
• 3:45
  Speaker 1: them one and the same. But history has kind of
• 3:48
  Speaker 1: shown like, non, there's six, we'll go with six for
• 3:51
  Speaker 1: the rainbow. So roy G BIV, which we learned in school.
• 3:54
  Speaker 1: Apparently I learned school. You did too, it's just roy
• 3:58
  Speaker 1: g h. Yeah. Well he was busy making is uh
• 4:04
  Speaker 1: cookies from figs too, so he had lots of stuff
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  Speaker 1: going on. Those are good. Oh yeah, I can mount
• 4:10
  Speaker 1: some pig nets. Yeah, because they're good for you, so
• 4:13
  Speaker 1: you can eat the whole bag one sitting if you want. Yeah.
• 4:16
  Speaker 1: I'd never buy them, but um, if I see them
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  Speaker 1: on like if you give blood or something, they're on
• 4:21
  Speaker 1: a snack table, that's when I get my fig Newton on. Yeah. So, um,
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  Speaker 1: Newton wasn't the only one. Before Newton, there was like
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  Speaker 1: a whole Celtic legend about the pot of gold at
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  Speaker 1: the end of the rainbow. There was God saying more
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  Speaker 1: bad after the Great flood and promising it would never
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  Speaker 1: happen again by showing rainbows come out after rains like
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  Speaker 1: it's fine, it's stopping, We're not going to flood the
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  Speaker 1: earth again. Um. Of course you can't find a pot
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  Speaker 1: of goal at the end of the rainbow because you
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  Speaker 1: cannot go to the end of a rainbow. Yes, you never.
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  Speaker 1: You can't go under a rainbow. You can't go over
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  Speaker 1: a rainbow. And we'll explain all this why, Yeah, and
• 4:58
  Speaker 1: just a second, sure, but first we have to talk
• 5:01
  Speaker 1: about to get to the bottom of how rainbows work,
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  Speaker 1: which to me I think is awesome. It's one of
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  Speaker 1: those things where okay, this is how it works, we
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  Speaker 1: understand it now. Yeah. I love science stuff like that,
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  Speaker 1: um baked in science. Yes, just done. It's not like
• 5:15
  Speaker 1: scientists think this is what's happening, and that's probably true,
• 5:19
  Speaker 1: but that remains to be seen. This is one of
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  Speaker 1: those ones where like, we know how rainbows work and
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  Speaker 1: here's how. But to get to the bottom of rainbows,
• 5:27
  Speaker 1: we have to understand how light works first. Yeah, and
• 5:30
  Speaker 1: I thought this article, even though there was a lot
• 5:32
  Speaker 1: more digging in to do, I thought the shopping cart
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  Speaker 1: explanation for for basically how light travels was pretty pretty
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  Speaker 1: darn good, fantastic. You know, one reason they say visible
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  Speaker 1: spectrum is because the light is moving so fast that
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  Speaker 1: you can't see it. It's like in the combination of
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  Speaker 1: all those is is white light like the sun is
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  Speaker 1: white light because all those colors are superimposed on one another.
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  Speaker 1: But when it hits like a water droplet or something else,
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  Speaker 1: it's gonna slow down enough. And we'll get to all
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  Speaker 1: this to where you can see those individual parts of
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  Speaker 1: the spectrum, right, and and that that shopping cart explanation,
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  Speaker 1: like you said, it definitely simplifies the whole thing, and
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  Speaker 1: it's not quite right, but it does a pretty good
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  Speaker 1: job of illustrating the principles that are going on. You know. Yeah,
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  Speaker 1: So basically light is moving at different speeds depending on
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  Speaker 1: what kind of medium, uh, it's traveling through. So, like
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  Speaker 1: I said, when it hits water, it's gonna slow down
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  Speaker 1: a lot. That's gonna change its speed. If you're pushing
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  Speaker 1: a shopping cart, the asphalt is the medium. If you
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  Speaker 1: push it onto grass, it's gonna slow down. That's a
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  Speaker 1: new medium. It's a new medium. It's gone. It's transition
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  Speaker 1: from one media to another. That's right. And if you
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  Speaker 1: hit that grass at an angle, and we've probably done this.
• 6:48
  Speaker 1: If you had a were able to steal a shopping
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  Speaker 1: cart as a kid, you're pushing your friends around in it,
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  Speaker 1: you're hauling through the neighborhood. And you hit that grass
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  Speaker 1: at an angle, and it's gonna take a really sharp
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  Speaker 1: turn because that front right wheel, let's say, is going
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  Speaker 1: to hit the grass and all of a sudden, really quickly,
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  Speaker 1: it's gonna be traveling at a much slower speed than
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  Speaker 1: the rest of it, and your friends gonna tumble out
• 7:09
  Speaker 1: and everyone's gonna have a good time exactly just where
• 7:12
  Speaker 1: your helmet. So so that imagine that the shopping cart
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  Speaker 1: is a photon of light or a beam of white
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  Speaker 1: visible sunlight, and the grass is a prism. Yeah. So
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  Speaker 1: the parking lot was air and it was moving through
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  Speaker 1: just find no problem. But when it hit that prism,
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  Speaker 1: it slowed down. And because it came at an angle,
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  Speaker 1: one side of the light hit sooner and it made
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  Speaker 1: it turn. And that it's called refraction. The bending of
• 7:42
  Speaker 1: light is refraction. Yeah. And in the case of a rainbow,
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  Speaker 1: that prism is a rain drop. So I mean this
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  Speaker 1: is the simple quick version. We'll get more detailed. But
• 7:51
  Speaker 1: when it hits that raindrop, it's gonna slow down and
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  Speaker 1: it's gonna bend. Right. So depending on the um refractive index,
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  Speaker 1: which is how much light bends depending on the wavelength um,
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  Speaker 1: the the wavelength of light, which is another term for color,
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  Speaker 1: is going to bend at a different angle. So when
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  Speaker 1: that visible light, which is all the colors of of
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  Speaker 1: the visible spectrum combined, hits a prism and it bends
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  Speaker 1: or a rain drop, right, it bends at different angles
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  Speaker 1: because the wavelengths are different, and so that visible light
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  Speaker 1: comes undone into its component wavelengths, which are all the
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  Speaker 1: colors of the rainbow, and they spread out. It's called dispersion, right, yeah,
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  Speaker 1: and that's it really, But like I said, in this case,
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  Speaker 1: we're talking about rain uh and because rain is um
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  Speaker 1: you know, raindrops are all different shapes and sizes, it's
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  Speaker 1: not gonna be as consistent as like a prism might be,
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  Speaker 1: but it's gonna have the same effect. It's gonna hit
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  Speaker 1: hit the rain drop, it's gonna slow down like the
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  Speaker 1: field digging into the grass of the shopping cart, and
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  Speaker 1: it's going to refract and some of it's gonna keep
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  Speaker 1: going someone it's gonna bounce back, but different the different
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  Speaker 1: color is going to bounce at a different angle, and
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  Speaker 1: it's all relative to where you are on the ground. Like,
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  Speaker 1: no person two people see the same rainbow. Right, So, um,
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  Speaker 1: when Abe right. So when when light hits the prism
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  Speaker 1: and it bends, like you said, because the different lights
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  Speaker 1: have different wavelengths. Different colors have different wavelengths. Um red
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  Speaker 1: has the longest wavelength, so it bends the least. I
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  Speaker 1: believe violet has the u shortest wavelength, so it bends
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  Speaker 1: the most. But because again because these different wavelengths, they
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  Speaker 1: bend differently, so that the light spreads apart, and when
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  Speaker 1: it exits the prism, it bends again and it forms
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  Speaker 1: that spectrum of separated light separated out. And this, if
• 9:58
  Speaker 1: you notice we keep saying the had been that's why
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  Speaker 1: a rainbow is an arc instead of like a right angle,
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  Speaker 1: because the light is bending. So Chuck, we've been kind
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  Speaker 1: of teasing this a little bit. But um, we'll get
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  Speaker 1: into exactly how you go from prison to rain drop
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  Speaker 1: and hence the rainbow right after this. All right, if
• 10:37
  Speaker 1: you want to see a rainbow, or if you're gonna
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  Speaker 1: see a rainbow, there need to be three conditions. Uh,
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  Speaker 1: the sun's got to be behind you, You're gonna have
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  Speaker 1: moisture in front of you, and you the sun must
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  Speaker 1: be shining. That sun, those sun's rays must be shining
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  Speaker 1: at forty two degrees of what's called the anti solar point,
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  Speaker 1: which is basically where the shadow of your head is
• 11:01
  Speaker 1: on the ground. So if you can see the shadow
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  Speaker 1: of your head, that's that's going to be that forty
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  Speaker 1: two degree anti solar point. So what you do is
• 11:10
  Speaker 1: you put your back directly to the sun right and
• 11:14
  Speaker 1: then turn forty two degrees, which I guess if it
• 11:17
  Speaker 1: were negative forty two degrees, you'll be turning to the left.
• 11:20
  Speaker 1: So I guess you'd be turning to the right a
• 11:22
  Speaker 1: little bit about forty two degrees, which you can kind
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  Speaker 1: of measure off in your head. It's not quite forty
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  Speaker 1: five degrees. And if you're looking at rain and the
• 11:30
  Speaker 1: sun is behind you, you're gonna see where that forty
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  Speaker 1: two agrees is, because once you hit that point, there's
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  Speaker 1: your rainbow. Yeah, but I mean you can move your
• 11:38
  Speaker 1: body around and still see the rainbow. I mean that's
• 11:41
  Speaker 1: where the sun is hitting. The Sun's got to be
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  Speaker 1: hitting at forty two degrees. I see. Okay, so Chuck,
• 11:48
  Speaker 1: it doesn't matter then where your head is. It's it's
• 11:53
  Speaker 1: the rain drops relation to the sun needs to be
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  Speaker 1: forty two degrees. The producer rainbow. Yeah, the sunshine must
• 12:01
  Speaker 1: be hitting it at forty two degrees. Okay, so let's
• 12:04
  Speaker 1: let's get back to basics again for a second. Um.
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  Speaker 1: When the sunlight hits the rain drop, each individual raindrop
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  Speaker 1: is acting like a prism, right, So that visible white
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  Speaker 1: light is hitting a raindrop, it's hitting it at an angle.
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  Speaker 1: It's going kaboom into like a colored spectrum inside the raindrop,
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  Speaker 1: and then it's gonna reflect back again, refract again, exiting
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  Speaker 1: the raindrop, so it bends again and it comes back
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  Speaker 1: at you. The thing is is when you see light
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  Speaker 1: colored light wavelength from a rain drop, you're not seeing
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  Speaker 1: the whole spectrum. You're not seeing millions of little rainbows.
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  Speaker 1: You're seeing one big rainbow. And the reason why is
• 12:49
  Speaker 1: because each individual raindrop, depending on its relation to you
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  Speaker 1: and I guess to the sun, is shooting one color
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  Speaker 1: at you. It's shooting all colors at you, but you're
• 13:00
  Speaker 1: only picking up on one color because there's only one
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  Speaker 1: color from a rain drop that is angled correctly to
• 13:08
  Speaker 1: you and your line of sight, so that it's the
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  Speaker 1: only one you're picking up on, his red. And then
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  Speaker 1: all of the rain drops around that rain drop are
• 13:18
  Speaker 1: doing the same thing. They're shooting about in relation to
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  Speaker 1: your line of sight red towards you. But then the
• 13:25
  Speaker 1: rain drops a little lower than that are shooting yellow,
• 13:29
  Speaker 1: and then lower than that green, and so on and
• 13:30
  Speaker 1: so on, and so you get the violet. And so
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  Speaker 1: these groups of rain these groups of rain drops are
• 13:36
  Speaker 1: producing this rainbow cumulatively as far as your line of
• 13:42
  Speaker 1: sight is concerned. Yeah, because the rain is just falling,
• 13:44
  Speaker 1: so where it is in the sky, I mean, as
• 13:46
  Speaker 1: it falls, it's going to be changing color. You know,
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  Speaker 1: it's not like frozen in midair or anything, but it
• 13:52
  Speaker 1: seems like it. But it seems like it, right exactly.
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  Speaker 1: And't that phenomenal? It really is. I just think that's
• 13:58
  Speaker 1: just as cool as it gets. Yeah, it's super cool.
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  Speaker 1: And um, you'll always notice to the sky under the
• 14:04
  Speaker 1: rainbow is going to be brighter than out. And when
• 14:06
  Speaker 1: you've got a double rainbow, which we'll get to the
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  Speaker 1: the area between those two is usually really dark, right,
• 14:15
  Speaker 1: And that's called the Alexander's Dark Band. Yeah, Alexander's Band
• 14:19
  Speaker 1: because he was Alexander Frio. Aphrodiseus was the first dude
• 14:25
  Speaker 1: to describe that. That's a great name, Alexander Aphrodiseus. Yeah,
• 14:30
  Speaker 1: it's pretty good. It sounds like a seventies exploitation movie
• 14:34
  Speaker 1: or something. Um. But yeah, So the reason why in
• 14:37
  Speaker 1: between the double rainbows you have Alexander's band is because
• 14:41
  Speaker 1: the light there is reflecting away from you and it's
• 14:48
  Speaker 1: so it's a dark area. So, uh, the sunlight hitting
• 14:52
  Speaker 1: those rain drops is going away and you're like, oh,
• 14:55
  Speaker 1: it's dark inside the rainbow. All of that light is
• 14:58
  Speaker 1: reflecting back to you and you're seeing all of the
• 15:02
  Speaker 1: different colors come at you and they're recombining indivisible lights,
• 15:05
  Speaker 1: so there's no color, it's just bright sunlight in the middle. Yeah,
• 15:10
  Speaker 1: and that you know sunlight. They also always describe it
• 15:12
  Speaker 1: as white, I mean sunlight as all the colors. We
• 15:15
  Speaker 1: just you know, can't see it. Yeah, we should really
• 15:17
  Speaker 1: do a whole um How Color Works episode. It's fascinating stuff.
• 15:22
  Speaker 1: But yeah, depending on whether you're a painter, um who's
• 15:26
  Speaker 1: mixing chemical color, whether you're a chemist or a physicist,
• 15:30
  Speaker 1: white is either the presence of all colors or the
• 15:33
  Speaker 1: absence of color. You know, it's kind of mind blowing.
• 15:37
  Speaker 1: We should totally do how color works. Uh. Well, I
• 15:40
  Speaker 1: guess after this break we'll talk a little bit more
• 15:42
  Speaker 1: about the double rainbow all the way and even well,
• 15:46
  Speaker 1: well we'll just leave it at that. What does it mean, so, Chuck,
• 16:10
  Speaker 1: you want to talk about double rainbows and what forms them,
• 16:13
  Speaker 1: it's pretty much the same thing, right, Yeah, the lights
• 16:16
  Speaker 1: refracted twice. Yeah, it's just a double refraction. Yeah. Well,
• 16:20
  Speaker 1: what's cool is if you look at a double rainbow,
• 16:23
  Speaker 1: the one on top, the higher one, that's the second refraction,
• 16:27
  Speaker 1: um is reversed, so rather than red being on the top,
• 16:33
  Speaker 1: it's on the bottom. Yeah, it's the reverse rainbow. Is
• 16:36
  Speaker 1: what a double rainbow is. And you can have a
• 16:38
  Speaker 1: triple and even a quad, but it's rare, Like I've
• 16:43
  Speaker 1: seen a little bit of a triple once. I think,
• 16:46
  Speaker 1: um to where you just see the faintest hint of
• 16:49
  Speaker 1: that third one, And if you're seeing that, that means
• 16:53
  Speaker 1: the initially I think it's called the primary and secondary.
• 16:56
  Speaker 1: That means your primary is super super super sharp. Yeah,
• 17:00
  Speaker 1: to where it looks like it's drawn on the sky,
• 17:02
  Speaker 1: painted on the sky, and then your secondary is gonna
• 17:05
  Speaker 1: be a little more faint than the third one because
• 17:07
  Speaker 1: the triple refraction, you know, it's it's not the easiest
• 17:10
  Speaker 1: thing to occur in nature. Yeah, and one of the
• 17:13
  Speaker 1: things that makes the primary rainbow and then hence the
• 17:16
  Speaker 1: secondary and I guess herst ayan so on rainbows bright
• 17:19
  Speaker 1: is the amount of sunlight and the number of raindrops,
• 17:24
  Speaker 1: because remember those raindrops that you're seeing, that the spectrum
• 17:29
  Speaker 1: is made up of light wavelengths that's coming at you
• 17:32
  Speaker 1: from a bunch of different raindrops, and they reinforce one another,
• 17:35
  Speaker 1: and the more they reinforce one another, the brighter the
• 17:37
  Speaker 1: rainbow is. Yeah, And you know, I mean I feel
• 17:40
  Speaker 1: like I usually see rainbows when it's not raining where
• 17:42
  Speaker 1: I'm standing, but um, that doesn't matter. It's you know,
• 17:47
  Speaker 1: you can be being rained on and still see the rainbow.
• 17:49
  Speaker 1: Well yeah, but it's like sometimes it's like a super
• 17:52
  Speaker 1: light rain where it has just rain really hard. Maybe
• 17:54
  Speaker 1: it's tapering off or maybe stopped all together. But the
• 17:57
  Speaker 1: point is where the rainbow is. It's it's not like
• 18:00
  Speaker 1: they said earlier, you can't drive up to a rainbow.
• 18:03
  Speaker 1: I'm gonna go up and find that thing because it's
• 18:06
  Speaker 1: a it's just a perspective trick basically, right. The only
• 18:10
  Speaker 1: apparently from this Scientific American article you sent, the only
• 18:14
  Speaker 1: visual information we get from a rainbow is the band
• 18:18
  Speaker 1: of its arc. Yeah, and everything else is what's around it, right, right, So, like,
• 18:23
  Speaker 1: if a rainbow seems really huge, it's because, say, the
• 18:26
  Speaker 1: mountains in the background looks small, which makes the rainbow,
• 18:29
  Speaker 1: by contrast, look very big and majestic. If we're close to, say,
• 18:34
  Speaker 1: like the mountains are like a cell phone tower or
• 18:36
  Speaker 1: something like that, the rainbow may look very small by comparison. Yeah,
• 18:41
  Speaker 1: and the way they like in it, and that I think, um,
• 18:43
  Speaker 1: and that article I think was like the human head.
• 18:46
  Speaker 1: It's like roughly the same size, but if it was
• 18:49
  Speaker 1: right in front of your face, it would block out
• 18:51
  Speaker 1: a whole movie screen. But it was further way, it
• 18:53
  Speaker 1: would just be like, hey, and there's that guy's head.
• 18:56
  Speaker 1: It's the same thing, same thing. Um. And then Phil Plate,
• 18:59
  Speaker 1: who is a who does the Bad astronomer Um blog
• 19:03
  Speaker 1: for Slate, he did a pretty good explanation of um
• 19:09
  Speaker 1: full circle rainbows. Yeah, I had never ever heard of
• 19:11
  Speaker 1: that until you sent me that, so it makes sense though,
• 19:14
  Speaker 1: it totally does. So. Remember we talked about a rainbow
• 19:17
  Speaker 1: arching over the sky and because the light is bent
• 19:20
  Speaker 1: out of the prism, Well, no, it's because it starts
• 19:23
  Speaker 1: on one part of the ground. And ends on another
• 19:24
  Speaker 1: part where the goal is. Um. The reason why it
• 19:28
  Speaker 1: has that arc is because what you're seeing is part
• 19:32
  Speaker 1: of what really is a full circle, and it's depending
• 19:36
  Speaker 1: on where you are. Now, you have a certain amount
• 19:39
  Speaker 1: of raindrops available for to reflect the light to you. Right,
• 19:46
  Speaker 1: So when you're on the ground and you're looking up
• 19:49
  Speaker 1: or just over to the horizon, you have a certain
• 19:51
  Speaker 1: amount of raindrops available to you to form a rainbow.
• 19:55
  Speaker 1: If you were able to get away from the ground,
• 19:58
  Speaker 1: you have even more raindrops that's just above you, but
• 20:01
  Speaker 1: now below you as well, and you can see a
• 20:04
  Speaker 1: full circle. That is the actual real rainbow. Yeah. So
• 20:08
  Speaker 1: a real a real rainbow, depending on where you are
• 20:11
  Speaker 1: in relation to the ground, is either a part of
• 20:14
  Speaker 1: a circle, an arc, or a full circle. Yeah. And
• 20:17
  Speaker 1: there was a picture. I mean he said that pilots
• 20:19
  Speaker 1: see him all the time or I guess if you're
• 20:22
  Speaker 1: an astute flyer, that's not just like asleep with a
• 20:25
  Speaker 1: black blanket of your face. Right. Um, you can look
• 20:29
  Speaker 1: out a window of a plane and see one two
• 20:30
  Speaker 1: because you're above it. It's pretty neat. I mean, there
• 20:33
  Speaker 1: was a photo of one and it was like, oh wow,
• 20:36
  Speaker 1: there's a full circle rainbow, full circle rainbow. It looks
• 20:39
  Speaker 1: it looks kind of like a lens flare a little bit,
• 20:42
  Speaker 1: but it's a rainbow lens flare. And um, phil Plate
• 20:45
  Speaker 1: had in that same blog post a double circle rainbow,
• 20:51
  Speaker 1: which was really neat. Yea, so go check that out.
• 20:55
  Speaker 1: I agree that was pretty cool. Um. Yeah, you know
• 20:59
  Speaker 1: that thing we're talking about earlier to about the perspective.
• 21:01
  Speaker 1: That's why the I think I thought you did it.
• 21:04
  Speaker 1: Don't be dumb about why the moon looks bigger? Have
• 21:07
  Speaker 1: you done that? No? It's so why can you see
• 21:10
  Speaker 1: the moon during the day sometimes? Why is that? Well
• 21:14
  Speaker 1: I'll tell you why, because I saw it like a
• 21:16
  Speaker 1: one the other day that was like super late in
• 21:18
  Speaker 1: the day. Well, the reason why, A better question is
• 21:21
  Speaker 1: why can't you see the moon all the time, even
• 21:23
  Speaker 1: during the day. So it's not the moon is very bright,
• 21:26
  Speaker 1: it's it's the brightest object in the sky, second only
• 21:29
  Speaker 1: to the sun. Sure, but it also gets its light
• 21:31
  Speaker 1: from the sun. So most of the time when you
• 21:34
  Speaker 1: can't see the moon during the day, it's because the
• 21:39
  Speaker 1: moon is behind you. So the light that it's getting
• 21:43
  Speaker 1: from the sun is behind you. Now, if the moon
• 21:46
  Speaker 1: is closer to the Sun. Like depending on where the
• 21:49
  Speaker 1: moon is in its lunar phase, then you can look
• 21:52
  Speaker 1: up and see the Sun and the Moon at the
• 21:54
  Speaker 1: same time. It's above the horizon. In other words, so
• 21:58
  Speaker 1: if you if the moon were always visible above the horizon,
• 22:01
  Speaker 1: you'd always be able to see it during the day.
• 22:04
  Speaker 1: And it just has to do with where it is
• 22:06
  Speaker 1: in relation to the Sun in the lunar phase. Does
• 22:09
  Speaker 1: that make sense? Yeah, if if if it's man, just
• 22:12
  Speaker 1: go watch that. Don't be dumb on it. Yeah. They
• 22:14
  Speaker 1: call that a bonus, an impromptu bonus. But the reason
• 22:19
  Speaker 1: why the moon will look really huge in the sky
• 22:21
  Speaker 1: is because the same thing we're talking about with the
• 22:23
  Speaker 1: perspective like the mountains, is like when you're low on
• 22:26
  Speaker 1: the horizon, it's gonna look enormous. Um if there's a
• 22:30
  Speaker 1: lot less stuff. Yeah, and near close to you, it's
• 22:34
  Speaker 1: gonna look very big. Yeah. And when I went to
• 22:37
  Speaker 1: Montana years ago, my explanation I got because you step
• 22:41
  Speaker 1: off the plane and you think, wow, this sky does
• 22:45
  Speaker 1: look bigger, Like what's the deal? They call it big
• 22:47
  Speaker 1: Sky Country and it really does look bigger. And the
• 22:49
  Speaker 1: explation I got from the locals, what's it's because the clouds.
• 22:53
  Speaker 1: So again it's just a perspective trick. So like the
• 22:56
  Speaker 1: mountains are way over there. I think it's just the
• 22:58
  Speaker 1: clouds that they typically out of, the big, huge puffy
• 23:02
  Speaker 1: clouds and um, but they look big in relation to
• 23:05
  Speaker 1: the mountains in the distance. Yeah, I think that's the deal.
• 23:08
  Speaker 1: So it makes the sky appear to look larger. Plus
• 23:10
  Speaker 1: I I imagine also there's fewer obstacles and obstructions, so
• 23:14
  Speaker 1: that it's just there's more sky to see and take
• 23:17
  Speaker 1: in just looking around, right, Yeah. Yeah, Like when I
• 23:19
  Speaker 1: lived in Yuma and you go out in the desert
• 23:21
  Speaker 1: and you can see like a hundred and eight degrees
• 23:24
  Speaker 1: from horizon to horizon, um, but they don't have the
• 23:27
  Speaker 1: cloud formations. Um. So the sky looks bigger in Montana
• 23:31
  Speaker 1: than it does like in the middle of the desert,
• 23:33
  Speaker 1: because most of the time in the desert you're going
• 23:35
  Speaker 1: to see that, you know, just blue, nothing but blue.
• 23:39
  Speaker 1: So there's no perspective, you know, like when you take
• 23:42
  Speaker 1: a picture of something to sell on eBay, you put
• 23:44
  Speaker 1: your fists next to it so people know how big
• 23:47
  Speaker 1: it is. Is that what people do? Any seeing quarters
• 23:51
  Speaker 1: and rulers never seen this, Yeah, that's quarters and rulers.
• 23:55
  Speaker 1: That's probably a better rule of them, right Yeah. Um, so, Chuck,
• 23:58
  Speaker 1: I got a couple other things. Apparently, when you look
• 24:01
  Speaker 1: at a rainbow, it's not uh an even division or
• 24:04
  Speaker 1: an even representation of all the colors. Um you see
• 24:09
  Speaker 1: the most red, it's the most visible. Apparently thirty eight
• 24:12
  Speaker 1: percent of a rainbow is red. Green is second at fifteen.
• 24:17
  Speaker 1: Blue is the least um with just eleven percent. What
• 24:23
  Speaker 1: is green? Green? Is? Okay? Rainbow green? Interesting? I wonder
• 24:30
  Speaker 1: what color blind We need to do one on color blindness,
• 24:32
  Speaker 1: but it's um. I looked into the article and it
• 24:36
  Speaker 1: was just sort of started to melt my brain, like
• 24:39
  Speaker 1: all this stuff, so I just said, no, put that
• 24:41
  Speaker 1: on the back burner. I think you did a great
• 24:43
  Speaker 1: job with this. Well we'll see, I'm sure we'll get
• 24:46
  Speaker 1: stuff wrong. H And lastly, the LGBT rainbow flag designed
• 24:51
  Speaker 1: in by a guy named Gilbert Baker really and it
• 24:54
  Speaker 1: used to have eight had turquoise and hot pink on
• 24:57
  Speaker 1: it before um, but apparently they ran out of fabric
• 25:00
  Speaker 1: for hot pink because the things like started to take off,
• 25:04
  Speaker 1: so they discontinued that. And I think the same went
• 25:06
  Speaker 1: for the turquoise one too interesting. We just went with
• 25:09
  Speaker 1: six and now is it a is it's a It's
• 25:12
  Speaker 1: a shining monument for establishments, for people to say I
• 25:18
  Speaker 1: want to go in there, and some people to say
• 25:20
  Speaker 1: I don't want to go in there. Sadly. You know.
• 25:24
  Speaker 1: We went to a gay bar in Philadelphia one afternoon, um,
• 25:29
  Speaker 1: and I say by accident, not like it was a
• 25:31
  Speaker 1: big deal. Was it the Blue Oyster? Now? And it
• 25:36
  Speaker 1: was in the afternoon, so it was just you know,
• 25:38
  Speaker 1: you know how it is in some bars in the afternoon,
• 25:40
  Speaker 1: like the that the serious regulars are in there. It
• 25:44
  Speaker 1: doesn't matter, gay, straight, whatever. And they were very cool guys,
• 25:47
  Speaker 1: and they were like, uh, and it was a big
• 25:48
  Speaker 1: group of us, and I think they were like, you know,
• 25:51
  Speaker 1: you know you're in a gay bar, right, And they
• 25:53
  Speaker 1: were kind of pointing that out. And I was like, oh, well, great,
• 25:57
  Speaker 1: serve me, bloody Mary. Then like I didn't know if
• 26:00
  Speaker 1: he thought we were I think he knew here from
• 26:02
  Speaker 1: out of town, so he was yeah, yeah, like, uh,
• 26:07
  Speaker 1: he didn't want any trouble. Oh got you. You know.
• 26:11
  Speaker 1: I was like, We're not like that, my friend. That's
• 26:13
  Speaker 1: just a happy accident. It does a good ending to
• 26:15
  Speaker 1: the Rainbow episode. Uh. If you want to know more
• 26:19
  Speaker 1: about rainbows, go check out our article on the site Rainbows.
• 26:23
  Speaker 1: Just type that word into how stuff works. Go check
• 26:25
  Speaker 1: out that Slate post and Scientific American in the Atlantic.
• 26:28
  Speaker 1: Some good stuff out there. Uh. And I said a
• 26:32
  Speaker 1: search bar, I think, and they're somewhere, which means it's
• 26:34
  Speaker 1: time for listener mail. That's right. I'm gonna call this,
• 26:39
  Speaker 1: uh Pliny the Beer. Uh. And this is from Corey
• 26:47
  Speaker 1: and I think Corries in San Francisco. Hey, guys, love
• 26:50
  Speaker 1: the podcast. I was listening to Cinnamon today and there
• 26:53
  Speaker 1: was an exchange about Pliny in a comment that there
• 26:56
  Speaker 1: was one and only I think anyone in the Bay
• 27:00
  Speaker 1: Area would know that there are two Plenties, the Elder
• 27:02
  Speaker 1: and the Younger. Um. That's because one of our local
• 27:05
  Speaker 1: breweries has a beer called Plenty the Elder, which is
• 27:08
  Speaker 1: known by beer officionados as one of the best beers
• 27:11
  Speaker 1: out there. In fact, it sells out weekly from local groceries.
• 27:15
  Speaker 1: They also make though a Plenty of the Younger, which
• 27:18
  Speaker 1: only comes out for two weeks a year. People wait
• 27:21
  Speaker 1: in line for hours just to get a pint. Uh.
• 27:24
  Speaker 1: And there was also a real historical Plenty the Elder
• 27:26
  Speaker 1: and Plenty the Younger who is his nephew. I didn't
• 27:30
  Speaker 1: realize it, and that is from Corey, and I did
• 27:33
  Speaker 1: look it up because the two weeks thing, I did
• 27:36
  Speaker 1: not believe it, but I just you know, sometimes you
• 27:37
  Speaker 1: want to see it with your own eyes. And uh, yeah,
• 27:40
  Speaker 1: Plenty of the Younger is a triple I p a.
• 27:43
  Speaker 1: Oh wow, that sounds awesome, named for the nephew and
• 27:46
  Speaker 1: adopted son evidently, and uh it is pub draft only.
• 27:50
  Speaker 1: They don't even bottle it. Very limited distribution locally, um,
• 27:55
  Speaker 1: and it's seasonal, so for just two weeks a year
• 27:59
  Speaker 1: um in February at the Bay of Bengal you can
• 28:03
  Speaker 1: get it in in a bar, I guess in San Francisco.
• 28:06
  Speaker 1: And it is a ten point two five center wow. Yeah,
• 28:13
  Speaker 1: as opposed to eight for the elder. Huh. And they're
• 28:17
  Speaker 1: both I p A s Yeah, ones that the double
• 28:20
  Speaker 1: and the triple so that yeah, and you can get
• 28:22
  Speaker 1: the Plenty of the Elder in the bottles. It's not
• 28:24
  Speaker 1: quite as exclusive. We'll have to try that on our tour. Yeah,
• 28:28
  Speaker 1: I guess only the elder and there's someone uh unless
• 28:31
  Speaker 1: we luck out and happen to be there during that
• 28:33
  Speaker 1: two week period. Huh. Well, now it's in February. But
• 28:37
  Speaker 1: if there's a bar out there that maybe wanted to
• 28:40
  Speaker 1: just say we're out, put it under the bar, save
• 28:42
  Speaker 1: it for a month for us, we'll be there. I
• 28:44
  Speaker 1: don't think that's gonna happen. If you want to correct
• 28:47
  Speaker 1: us after we get something flagrantly wrong, like we did
• 28:51
  Speaker 1: with the whole pliny thing, you can tweet to us
• 28:54
  Speaker 1: at s y s K podcast. You can post it
• 28:57
  Speaker 1: on Facebook dot com, slash stuff you Should Know. You
• 28:59
  Speaker 1: can send us an email to Stuff Podcast at how
• 29:02
  Speaker 1: stuff Works dot com, and, as always, join us at
• 29:04
  Speaker 1: our home on the web, Stuff you Should Know dot com.
• 29:13
  Speaker 1: For more on this and thousands of other topics, is
• 29:15
  Speaker 1: it how stuff Works dot com