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How the Aurora Borealis and Aurora Australis Work · Stuff You Should Know

0:01
Speaker 1: Welcome to Stuff You Should Know from how Stuff Works
0:04
Speaker 1: dot com. Hey, and welcome to the podcast. I'm Josh Clark,
0:14
Speaker 1: There's Charles w Chuck Bryant, and Jerry's over there. So
0:19
Speaker 1: this is Stuff you Should Know the podcast. Uh, we
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Speaker 1: You can get stuff Mom never told you. Yes, and apologize.
1:35
Speaker 1: I apologize for my voice. Oh yeah, what's up with
1:39
Speaker 1: your voice? Man? I've just had this upper respiratory thing
1:42
Speaker 1: that won't go away, that stinks, and so unless I'm
1:46
Speaker 1: constantly wetting my throat, it gets weirdly deep and cracky.
1:51
Speaker 1: So are you paying a lot more than usual? Well,
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Speaker 1: I'm drinking a lot of water. I'm peeing a lot,
1:55
Speaker 1: but I would literally have to drink between every sentence
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Speaker 1: to keep it silky smooth. Oh do you want to
2:01
Speaker 1: record today? No, I'm fine. I'm not in pain, but
2:05
Speaker 1: I just don't want anyone's ears to be in pain.
2:07
Speaker 1: Have you heard of um? Oh? Man, now that I
2:11
Speaker 1: say it, I realized I don't know the name of
2:14
Speaker 1: the brand. But you know those like cough drops that
2:17
Speaker 1: are actually like candy, but they market them as cough drops,
2:19
Speaker 1: the cherry flavored ones. M No, I mean like they're
2:24
Speaker 1: literal candy. Um no, but it's basically the most delicious
2:31
Speaker 1: jolly rancher you've ever had. It lacks the sour, it's
2:34
Speaker 1: all sweet. So it's green apple. No, they're red. I
2:38
Speaker 1: can't remember what they're called. People are screaming at their um. Yeah,
2:42
Speaker 1: well their phones, their tablets, their computers. Right now, settled down, everybody, Yes,
2:47
Speaker 1: we chuck and I agree with you. This is maybe
2:50
Speaker 1: the worst intro we've ever done. And Jerry does too.
2:54
Speaker 1: So let's get to it, shall we. So we're talking
2:56
Speaker 1: aurora's today. Yeah, and generally we're talking about the two
3:03
Speaker 1: most famous auroras. Uh And I say too, because I
3:06
Speaker 1: don't even want to give I don't want to short
3:09
Speaker 1: change the Aurora Australis. No, it definitely does get short changed,
3:14
Speaker 1: though totally. Did you Did you come upon why? I
3:18
Speaker 1: came upon the explanation a couple of times? Oh about why? Yeah?
3:23
Speaker 1: Uh I didn't. But I'm gonna have a guess. Okay,
3:26
Speaker 1: let's have it. Is it not quite as magnificent? Nope?
3:29
Speaker 1: Are there not as many people there? Yes? There you go,
3:33
Speaker 1: There are fewer. There's there's less land around the South
3:38
Speaker 1: Pole as there is around the North Pole. Um, I
3:41
Speaker 1: should say the magnetic South and North pole. Um. So
3:45
Speaker 1: there's fewer eyes to see it, so the grandeur of
3:47
Speaker 1: it is is um less obvious too as many people.
3:52
Speaker 1: But yeah, that's that's why the Northern Lights get all
3:54
Speaker 1: the all the top billing. Plus, no one ever named
3:57
Speaker 1: a strain of weed after the Aurora Australis out about
4:00
Speaker 1: that too. Southern Lights, what is that? I bet you
4:03
Speaker 1: there's one. There's a poison. There a like a head
4:07
Speaker 1: shop in Atlanta called Southern Lights. I think it's a bookstore.
4:11
Speaker 1: Oh got it? Wink wink. Oh yeah, but where you
4:15
Speaker 1: can where you can buy rush and spice books. Well,
4:21
Speaker 1: I I don't understand. I'm just kidding. Let's see. Is
4:25
Speaker 1: that like a code for something? Well, I thought you
4:27
Speaker 1: were giving me the code, Chuck. I think it's a
4:31
Speaker 1: real bookstore, gardening books. This is the most confused I've
4:37
Speaker 1: ever been on this show. Like we're on a cell
4:39
Speaker 1: phone and have to keep things, you know, straight up?
4:42
Speaker 1: All right, all right, let's get back to it. I
4:46
Speaker 1: don't want to confuse you so Auroras, because I want
4:51
Speaker 1: to make sure that you is uh comes through Um
4:56
Speaker 1: the the there are two and Chuck apparently until very
4:59
Speaker 1: re cerently. It was assumed because people couldn't see him
5:03
Speaker 1: at the same time, but it was assumed that there
5:07
Speaker 1: the northern lights that you were seeing the Aurora borealis. Um,
5:12
Speaker 1: if you could simultaneously see the Aurora Australias, you would
5:17
Speaker 1: be seeing a mirror image of one another. And they
5:20
Speaker 1: recently found out that that's absolutely not true at all.
5:22
Speaker 1: They finally got someone down there to look some some
5:25
Speaker 1: poor sap had to run. He's like, no, it's it's
5:29
Speaker 1: way way too different. It's not the same. I don't
5:33
Speaker 1: exactly know how they do it. They must have observed
5:35
Speaker 1: it from space, but they saw They are convinced now
5:38
Speaker 1: that it's not a mirror image any longer. Um. But
5:42
Speaker 1: this is it's not that surprising that they're just now
5:45
Speaker 1: kind of um figuring that out, because it wasn't until
5:49
Speaker 1: too terribly long ago that people thought the aurora was
5:53
Speaker 1: things like a giant camp fire on the other side
5:56
Speaker 1: of the ocean being reflected in the sky or um uh,
6:01
Speaker 1: you know, like the sun's rays peeking up from under
6:05
Speaker 1: the earth where it was day when it was night
6:07
Speaker 1: where you were. Um. There's been a lot of explanations,
6:11
Speaker 1: some of them goofier than others. Um, But it wasn't
6:14
Speaker 1: until I think the nineteenth century that we really figured
6:17
Speaker 1: out what was going on. And it was a dude
6:19
Speaker 1: in Norway, appropriately enough, because Norway is a good place
6:22
Speaker 1: to see the Northern Lights. Yeah. I mean they've been
6:25
Speaker 1: around obviously, since there have been people to watch them,
6:29
Speaker 1: since ancient times, people have been observing them. But like
6:32
Speaker 1: you said, when you know, when you're talking about indigenous
6:35
Speaker 1: peoples and vikings and things, they're gonna have, uh, you know,
6:38
Speaker 1: they had a more limited understanding of science, so they
6:40
Speaker 1: had all these uh, fanciful descriptions of what they might be.
6:45
Speaker 1: But um, are you talking about the first person to
6:49
Speaker 1: use the term are you talking about? No? Actually I
6:53
Speaker 1: jumped past him and he definitely deserves pop, so let's
6:56
Speaker 1: talk about him. Yeah, Pierre Pierre Gasindi or Galileo and
7:01
Speaker 1: Galileo Galilee apparently at the same around the same time,
7:05
Speaker 1: both witnessed the September twelfth, nine sixty one display, and um,
7:11
Speaker 1: both kind of you know, put it in their own
7:13
Speaker 1: words how wonderful it was. But it wasn't until I
7:16
Speaker 1: believe you were talking about eighteen physicist name Christian Birkeland
7:22
Speaker 1: in Norway. Yeah, I think it was sixteen sixty one.
7:27
Speaker 1: What did I say, Oh man, Yeah, okay, And they
7:34
Speaker 1: saw it on Yeah, they saw it on the same night, right,
7:36
Speaker 1: and they both went out and I don't think they
7:39
Speaker 1: were having a conversation and then both ran out to
7:42
Speaker 1: write it down. It seems like they simultaneously came up
7:46
Speaker 1: with this idea at the same time from seeing it
7:49
Speaker 1: on the same date. Is that is that correct? Yeah?
7:52
Speaker 1: I think they both saw the same uh fantastic display
7:57
Speaker 1: on the same night, but they both came up with
8:00
Speaker 1: the same idea to name it Aurora Borealis. Oh. Well,
8:05
Speaker 1: that I don't know. They share credit, which to me
8:09
Speaker 1: means they probably don't know right and would just feel
8:12
Speaker 1: bad giving it to one of them. Yeah, because history
8:15
Speaker 1: has riddled with that kind of thing where you know,
8:18
Speaker 1: everybody says, oh no, it was really Alexander Graham Bell
8:22
Speaker 1: and Elijah Gray. There's definitely no winner in that. Or
8:25
Speaker 1: maybe one of them said I say, Aurora, you say,
8:28
Speaker 1: and he went Borealis and they had got a little
8:31
Speaker 1: chant going. It was like a Beastie Boys concert. Yeah, exactly,
8:35
Speaker 1: so they it was that the what was the Norwegian
8:39
Speaker 1: scientists who Kidistian Berkeland. So they were already called the
8:44
Speaker 1: Northern Lights from at least the Renaissance on um or
8:47
Speaker 1: I guess that would be pre Renaissance, didn't Galileo helped
8:50
Speaker 1: kick off the Renaissance. I think he cut the ribbon.
8:53
Speaker 1: So um, Christian Berkeland he was the one who he
8:59
Speaker 1: came up with the modern interpretation of what the auroras are. Yeah,
9:04
Speaker 1: he was pretty right too, I agree, like he just
9:07
Speaker 1: I don't know if he just pulled this one out
9:09
Speaker 1: of his hat or what, but he definitely he he
9:12
Speaker 1: decided that what the aurora auroras are aurora Apparently you
9:18
Speaker 1: put it a E on the end, and that's how
9:20
Speaker 1: you pluralize it. When um, he figured out that they
9:25
Speaker 1: have something to do with electrons in outer space interacting
9:30
Speaker 1: with the magnetosphere around Earth. And it turns out he
9:34
Speaker 1: was absolutely right. Yeah, he recreated this in a vacuum
9:38
Speaker 1: chamber successfully, but he wasn't a percent right he I
9:43
Speaker 1: think he said that, um, and we'll get to this later,
9:47
Speaker 1: but the Aurora borealis and auroras in general are have
9:51
Speaker 1: a characteristic shape, which is an oval ring. And he
9:55
Speaker 1: did not know this at the time, because he thought
9:59
Speaker 1: that these electrons were coming from the sun, which is
10:02
Speaker 1: not quite true. No, no, it's not. It's a little
10:05
Speaker 1: more complex than that. Like, his interpretation of the whole
10:08
Speaker 1: thing was pretty seemed to be correct, and you actually
10:11
Speaker 1: run into it here there. I saw it on a
10:13
Speaker 1: couple of pretty respectable sites that were basically giving the
10:17
Speaker 1: Berkeland interpretation of aurora um phenomenon. But it turns out
10:23
Speaker 1: there's an extra step in there that he didn't account for.
10:26
Speaker 1: So do you want to talk about the magnetosphere real quick? Well,
10:29
Speaker 1: I think quickly that we should shout out one more researcher. Uh.
10:33
Speaker 1: And this was nineteen sixty four. There was a grad
10:36
Speaker 1: student in Japan name Uh, Well you want to you
10:38
Speaker 1: always take our Japanese you want to do that one? Uh?
10:41
Speaker 1: Shoon Ichi Aka Sofu, very nice, thank you. Uh. And
10:45
Speaker 1: he actually in nineteen sixty four saw these photos, examined them,
10:49
Speaker 1: examined them closely, and notice that they were rings. And
10:53
Speaker 1: I believe that he was the first one to say, hey,
10:55
Speaker 1: these things are oval. I think he actually predicted them
10:59
Speaker 1: that they would be oval mathematically without even observing him.
11:03
Speaker 1: And then then yeah, then once we started going into
11:07
Speaker 1: space and looking at from satellites. They said, yep, aka
11:11
Speaker 1: Sofu was right through math dude. He was like, nope,
11:16
Speaker 1: it'll be a ring. And it turns out he's right
11:18
Speaker 1: and the the the So what you're seeing with the
11:21
Speaker 1: northern lights and the southern lights, um are actually connections
11:27
Speaker 1: toward ovals that go around the North pole and the
11:30
Speaker 1: South pole. And what what it is again, it's it's particles,
11:36
Speaker 1: highly charged particles from out of space interacting with the magnetosphere. Yeah.
11:41
Speaker 1: So so you're ready to talk about the magnetosphere. So
11:47
Speaker 1: the this is kind of astounding to me. We're not
11:51
Speaker 1: entirely certain why the Earth has a magnetic field from
11:54
Speaker 1: what I can tell. Did you know that? Yeah, I
11:57
Speaker 1: mean they have their idea, but um, they're not positive right.
12:01
Speaker 1: That astounds me. Um Supposedly from the rotation of molten
12:07
Speaker 1: iron in the outer core inside the Earth, UM that
12:12
Speaker 1: generates this electrical field that surrounds the Earth, the magnetosphere.
12:18
Speaker 1: That's the current hypothesis. It's probably right, but the fact
12:21
Speaker 1: that we don't know exactly what creates the magnetosphere around
12:25
Speaker 1: the Earth is just weird to me. Yeah, I'm with
12:30
Speaker 1: you there, So what with this whatever is causing it.
12:34
Speaker 1: We know that there's a magnetic shield basically around Earth.
12:38
Speaker 1: That's that is probably caused by that that iron rotating
12:42
Speaker 1: inside the Earth. And this magnetic shield has helped preserve Earth,
12:46
Speaker 1: like we would not be here if the magnetosphere wasn't there.
12:49
Speaker 1: The atmosphere probably wouldn't be around Earth if the magnetosphere
12:52
Speaker 1: wasn't there. It protects us from bursts of radiation of
12:58
Speaker 1: highly charged um ions and and particles that are blasted
13:04
Speaker 1: out from the Sun and are just traveling throughout the
13:06
Speaker 1: Solar System from other stars and we're bombarded. Earth is
13:10
Speaker 1: bombarded by the stuff constantly, and Um, the magnetosphere acts
13:15
Speaker 1: to actually um deflect most of it, a lot of it. Yeah,
13:26
Speaker 1: we need the magnetosphere. So we've got this thing surrounding
13:30
Speaker 1: us and and it's great. It keeps us alive. But
13:33
Speaker 1: it also creates the basis for um for Aurora aurora. Yes,
13:39
Speaker 1: all right, so how this happens, um, It sounds kind
13:43
Speaker 1: of complicated, but it's really not. When you look at it. UM, Like,
13:48
Speaker 1: like you said, there's the Sun is like this big
13:52
Speaker 1: ball of gas. It constantly spits out and burps out
13:56
Speaker 1: all kinds of things in the form of energy and
13:59
Speaker 1: um radiation and what's called the solar wind, solar flares,
14:05
Speaker 1: coronal mass ejections. Uh. And we talked about all of
14:08
Speaker 1: this in various episodes, but notably our terrible episode on
14:12
Speaker 1: the Sun, our legendary episode. Anything that has anything remotely
14:16
Speaker 1: to do with the Sun is usually a poor episode
14:18
Speaker 1: for us. Uh. And, like you said, most of the
14:21
Speaker 1: time these things get deflected, but sometimes some of the
14:25
Speaker 1: stuff gets trapped in the magnetosphere, right, well, or so
14:30
Speaker 1: this stuff that's being spit out from the Sun, it's
14:32
Speaker 1: it's a lot of it's plasma, right, which is the
14:35
Speaker 1: fourth state of matter. And that's like highly charged particles
14:41
Speaker 1: that hit the magnetosphere. And when they hit the magnetosphere,
14:44
Speaker 1: they basically transfer their current to the magnetosphere. They produced
14:47
Speaker 1: an electrical charge in it. That's right, And all kinds
14:52
Speaker 1: of fun stuff happens once that happens. And so what, well,
14:55
Speaker 1: this is where the Berkland interpretation basically kind of starts
14:59
Speaker 1: to diver It's right. So Berkland's idea was those particles
15:03
Speaker 1: travel through the magnets for down the field lines of
15:07
Speaker 1: the Earth's magnetic field and um. They directly create the
15:14
Speaker 1: um the aurora. Yeah, Like if you looked at if
15:17
Speaker 1: you could see the magnetic field around the Earth, it
15:21
Speaker 1: would have a big, long whiskey tail sort of like
15:24
Speaker 1: it would sort of look like a comet surrounding the
15:26
Speaker 1: Earth and these magnetic lines that it travels. Once it
15:30
Speaker 1: hits those field lines, it goes along that that path
15:34
Speaker 1: on the northern and southern poles, right, so down that
15:37
Speaker 1: tail and if you if you so, the reason that
15:41
Speaker 1: it has that tail. On the one side, it's squished
15:44
Speaker 1: and the the it's it goes it's about six to
15:47
Speaker 1: eight earth radii outside of the Earth, in between the
15:51
Speaker 1: Earth and the Sun, but it's being pressed up against
15:54
Speaker 1: the Earth, threats being squished on the sun side. On
15:57
Speaker 1: the night side, that tail is being formed, and apparently
16:01
Speaker 1: that's extraordinarily long. It goes well well past the Moon,
16:05
Speaker 1: something like up to a thousand earth radii past the
16:08
Speaker 1: Earth on the other side. Right, But if there wasn't
16:11
Speaker 1: solar wind and the Earth's magnetosphere just formed, I think
16:15
Speaker 1: it's natural shape and there was no pressure from the
16:17
Speaker 1: solar wind on it. What you would see if you
16:20
Speaker 1: were looking at it from outer space is so the
16:23
Speaker 1: Earth is a dipole magnet You've got the positive in
16:26
Speaker 1: the negative one on each pole. Right, it would look
16:30
Speaker 1: like the Earth's magnetosphere would look like an eight on
16:33
Speaker 1: its side to where the top of the eight was
16:36
Speaker 1: coming out the left side of the Earth and the
16:40
Speaker 1: bottom of the eighth would be coming off of the
16:42
Speaker 1: right side. There and where they came together would be
16:45
Speaker 1: Earth's magnetic poles. And where those the magnetosphere comes in
16:50
Speaker 1: contact with the Earth at the poles are what it
16:53
Speaker 1: called the polar cusps. And apparently this is basically a
16:58
Speaker 1: direct pipeline, a funnel for particles to go right toward
17:02
Speaker 1: the polls. And that's why particles tend to accumulate, or
17:06
Speaker 1: the northern lights tend to um accumulate and be seen
17:09
Speaker 1: every night at these poles in rings, because they're being
17:13
Speaker 1: funneled there by the magnetosphere. Yeah, it's like when uh
17:16
Speaker 1: in the original Star Wars and New Hope when Luke
17:18
Speaker 1: fires at the end toward the Death Star and it
17:21
Speaker 1: and he gets sucked in that little hole that's like
17:23
Speaker 1: the polar cusp of the Death Star. That is a
17:27
Speaker 1: great analogy. So let's take a break, shall we. I'm
17:32
Speaker 1: hanging on here by my fingernails, and I need to
17:34
Speaker 1: regain myself. I think they call this a cliffhanger. All right,
18:01
Speaker 1: so we're back to describe the second part of how
18:05
Speaker 1: this works. Yes, and more. Uh So, when this charge
18:09
Speaker 1: it's cutting across this magnetic field, following those lines toward
18:14
Speaker 1: the it's actually called the magnet magneto tail. I can't
18:20
Speaker 1: believe they actually named it that. It's great. Uh And
18:23
Speaker 1: like you said from the beginning, it generates this electric
18:26
Speaker 1: current and as it goes it generates more and more currents,
18:29
Speaker 1: just sort of building up current until it hits the ionosphere. Right,
18:34
Speaker 1: So here's this really important step, right, And berklen knew this.
18:37
Speaker 1: He he guessed this, but he we'll we'll explain what
18:39
Speaker 1: you got wrong after we explain what's right. How about that? So,
18:43
Speaker 1: when um, these particles charge the magnetosphere, there's particles that
18:50
Speaker 1: are already trapped in the the magnetosphere already, right, And
18:56
Speaker 1: when solar winds and plasma and these highly charged particles
19:00
Speaker 1: hit the magnetosphere and electrify it, it kind of shakes
19:03
Speaker 1: loose these trapped particles, right. Yeah, Well, these trapped particles
19:08
Speaker 1: are ions, meaning they have either an extra electron or
19:12
Speaker 1: they're missing an electron, but either way they're not neutral.
19:16
Speaker 1: They have a charge positive or negative charge. And those
19:19
Speaker 1: things go careening through the magnetosphere toward Earth, down through
19:23
Speaker 1: the atmosphere, and when they hit the atmosphere, they start
19:26
Speaker 1: interacting with some of the atoms and molecules, specifically oxygen
19:30
Speaker 1: and nitrogen in the Earth's atmosphere. And when they do, baby,
19:35
Speaker 1: they release photons. That's right, And that that outer region,
19:39
Speaker 1: the ionospheres where most of that oxygen and nitrogen is
19:42
Speaker 1: and uh, you're right. They get together and have a
19:45
Speaker 1: little bit of a party. They exchange some energy with
19:48
Speaker 1: one another, uh, get to know one another a little bit.
19:52
Speaker 1: And that absorption of energy by the oxygen and nitrogen
19:56
Speaker 1: ions it gets those electrons, it gets their electrons excite it, right,
20:01
Speaker 1: So they the um oxygen and nitrogen they have like uh,
20:05
Speaker 1: they have electrons orbiting them, right, But they're just in
20:09
Speaker 1: this low level orbit. It's like a whatever kind of energy, right,
20:12
Speaker 1: it's a it's a party that hasn't started yet. It
20:14
Speaker 1: is this is kind of hanging out. Maybe the pizza
20:17
Speaker 1: hasn't arrived yet. Um, that kind of thing. So the
20:21
Speaker 1: when the when the ions arrived though, they're bringing the pizza,
20:25
Speaker 1: and then some they're bringing the northern lights with them, right, Um,
20:29
Speaker 1: and they they get the party started, those electrons in
20:33
Speaker 1: the lower orbit suddenly move up to a larger orbit
20:36
Speaker 1: further out. And when that happens, energy has been gained. Right. Yeah,
20:41
Speaker 1: that's called a high energy orbital Okay, So when that happens,
20:45
Speaker 1: it's basically destined to come back to its lower energy orbit. Right.
20:50
Speaker 1: The party has got to end at some point because
20:52
Speaker 1: to get tired, they need to go home. The Sun's
20:56
Speaker 1: coming up, that kind of thing. So either by it
20:59
Speaker 1: changes in the vacuum state or because of the application
21:03
Speaker 1: of an external electrical field that orbit, that electron goes
21:08
Speaker 1: back to its original lower orbit. When it does, since
21:11
Speaker 1: it's gained energy, and energy can neither be created nor destroyed. Um,
21:16
Speaker 1: that has to go somewhere, And it goes somewhere by
21:20
Speaker 1: the production or the emission I should say, of a photon,
21:23
Speaker 1: a packet of light. So light is emitted when that
21:26
Speaker 1: electron goes back down to its lower or after the
21:29
Speaker 1: party's over, that's right. And because oxygen ions radiate red
21:33
Speaker 1: and yellow light, nitrogen ions radiate red, blue, and violet light.
21:38
Speaker 1: Depending on where you are, This can happen at different
21:41
Speaker 1: UM I guess different altitudes. UH blue and violet UM
21:47
Speaker 1: generally less than seventy two miles kilometers, green is going
21:51
Speaker 1: to be sight milesight kilometers, and then redh more than
21:58
Speaker 1: a hundred eight miles, which is about a hundred and
22:00
Speaker 1: eighty kilometers, So that accounts for the different colors. If
22:03
Speaker 1: you look up or if you've ever been lucky enough
22:05
Speaker 1: to see one of the auroras um, either the Australias
22:10
Speaker 1: or Borealis, you're gonna see My favorite is the green,
22:13
Speaker 1: but you're gonna see all kinds of um, blue, green, violet,
22:18
Speaker 1: and red lights. Well, and apparently the green just confounded
22:21
Speaker 1: scientists because they're like, wait, so, yeah, oxygen radiates red
22:25
Speaker 1: and yellow light. That's that's great. Nitrogen is is red,
22:29
Speaker 1: blue and violet. Got that, But where is this green
22:32
Speaker 1: coming from? They couldn't link at any particular atom or molecule,
22:36
Speaker 1: and then they realized that it has to do with
22:39
Speaker 1: the rarefied air in the upper upper atmosphere, that the
22:43
Speaker 1: the conditions found up there are not going to be
22:46
Speaker 1: found anywhere else on Earth. UM and that it's actually
22:50
Speaker 1: it is oxygen atoms and oxygen molecules producing the green.
22:54
Speaker 1: You just wouldn't see it anywhere else but specifically up
22:56
Speaker 1: in the upper atmosphere. Yeah, well it's oxygen and nitrogen
23:00
Speaker 1: doesn't have something to do with it. I saw it
23:02
Speaker 1: was just oxygen emitting the green, Okay, but the I mean, yes,
23:06
Speaker 1: nitrogen produces some of the other colors. Yeah. So, uh,
23:11
Speaker 1: if you're watching these, if you're one of the people,
23:13
Speaker 1: they very in brightness, you know they can right now.
23:16
Speaker 1: And actually for a while now, we've been in a
23:19
Speaker 1: pretty low uh what's it called the solar cycle. Yeah,
23:23
Speaker 1: we've been in a kind of a bummer of a
23:25
Speaker 1: solar cycle for a while now, and these auroras haven't
23:29
Speaker 1: been nearly as spectacular as they have been in years
23:32
Speaker 1: past because of that. I think they peaked in two
23:34
Speaker 1: thousand and twelve, but even that that was a solar
23:38
Speaker 1: maximum that when it peaked and it started to decline.
23:41
Speaker 1: So solar cycle happens every eleven years, and we're starting
23:44
Speaker 1: up our twenty third one now. Um, but this past one,
23:48
Speaker 1: the twenty second one, was like the lowest in a century.
23:52
Speaker 1: It was the weakest one in a cential. Yeah, the
23:53
Speaker 1: weakest maximum even but even still weren't there. Couldn't you
23:57
Speaker 1: see northern lights once in a while, like fairly far
24:00
Speaker 1: a few years back. I don't remember. I stily here.
24:03
Speaker 1: You can see it in or that at times, you
24:06
Speaker 1: can see them in the southern United States, but I
24:08
Speaker 1: don't remember seeing them ever. I don't either, And supposedly
24:11
Speaker 1: there was a date in either or nine nine where
24:14
Speaker 1: they were visible from Cuba that they were that far south.
24:18
Speaker 1: That might be as far south as has ever been recorded. Actually,
24:22
Speaker 1: but normally you can see them the closer to the
24:25
Speaker 1: poles you are, so specifically, uh, in the North Pole
24:29
Speaker 1: or South Pole, the Arctic or Antarctica, you can see
24:32
Speaker 1: them basically every night. Um, there are specific conditions to
24:36
Speaker 1: where they're more brilliant than others. Right, So, um, if
24:40
Speaker 1: you're looking for what did you say, if people watch them,
24:42
Speaker 1: they um they put them into categories one through four. Yeah.
24:47
Speaker 1: I didn't say that yet, but uh yeah zero up
24:50
Speaker 1: through four from barely can see it. Two Holy cow,
24:54
Speaker 1: that's amazing, right, So if you're looking for the Holy Cow,
24:58
Speaker 1: that's amazing. Four. Um, you would go looking on a
25:02
Speaker 1: moonless night where there's no clouds where it's super super cold,
25:08
Speaker 1: and maybe October or February or March. Yeah, I saw it. Also, Um,
25:13
Speaker 1: winter is the best time to see him, winter in
25:17
Speaker 1: the north and winter in the south. Oh yeah, yeah, alright,
25:21
Speaker 1: well I'll buy that. Yeah. I thought that was weird
25:24
Speaker 1: that there's any confusion on that, because yeah, there's like
25:28
Speaker 1: whole tourist industries that are have grown up around us.
25:32
Speaker 1: Well maybe that's how they're trying to get you. Like
25:34
Speaker 1: it's December, but you should still come. It's great, all right,
25:37
Speaker 1: you just come back in December too. Uh So, northern Norway,
25:41
Speaker 1: UM Alaska. Obviously you're gonna get some pretty good stuff.
25:44
Speaker 1: Um southern Alaska. Like you said, as things as you
25:47
Speaker 1: go south, it's going to diminish a little bit. But
25:49
Speaker 1: I would imagine southern Alaska you're still getting a pretty
25:52
Speaker 1: good show, right, don't you think. Yep, Sometimes you could
25:56
Speaker 1: see him and I think this will probably be on
25:58
Speaker 1: par with southern Alaska. Just at the worst feeling, I'm
26:02
Speaker 1: going to get a bunch of email geography. But you
26:06
Speaker 1: can sometimes see them in Scotland even Okay, Um, I
26:12
Speaker 1: believe that maybe the northern UK you could conceivably see
26:17
Speaker 1: them once in a while. But I got the impression
26:19
Speaker 1: that Scotland is more regular than say, over here in
26:23
Speaker 1: the northern United States. Yeah, I think it says here
26:26
Speaker 1: Scotland in the UK maybe one to ten times a month,
26:29
Speaker 1: and then the US and Canada near the border maybe
26:33
Speaker 1: just a couple to three or four times a year. Right, Okay,
26:37
Speaker 1: I've never seen him of you know, and it says
26:39
Speaker 1: once or twice a century. You might seem in the
26:42
Speaker 1: southern United States. So if it happened in the late eighties,
26:45
Speaker 1: we missed our shot, my friend, which is weird because
26:48
Speaker 1: I would have been in Toledo. Maybe I was sleeping.
26:53
Speaker 1: It just seems like something that my mom would have
26:55
Speaker 1: woken me up for. Yeah, I mean, I don't it
26:58
Speaker 1: doesn't stand out to me. Is like science teachers would
27:02
Speaker 1: have probably said something. But remember remember Haley's comment. When
27:07
Speaker 1: that came through, everybody was talking about Yeah, I guess
27:11
Speaker 1: maybe it could have caught everybody by surprise. I don't
27:15
Speaker 1: know about that. I think this is pretty predictable, right,
27:19
Speaker 1: I don't know that that's true. What that is predictable? Yeah, well,
27:24
Speaker 1: I think the the conditions, they know the conditions where
27:28
Speaker 1: they will be the best. But maybe, like the weather,
27:31
Speaker 1: you can't predict those conditions, right Suppose yeah I saw
27:35
Speaker 1: somewhere something like, um, they can predict them within a
27:38
Speaker 1: few hours. Oh well yeah, it's not enough time to
27:41
Speaker 1: get to Norway. No it's not from Georgia. So so
27:45
Speaker 1: the scale is zero to four it like we were saying.
27:47
Speaker 1: And the people that enthusiasts that watch these they actually
27:50
Speaker 1: can help contribute to science because you know, there's not
27:53
Speaker 1: always someone like you said, if it's just a few hours, notice,
27:57
Speaker 1: there's not always a scientist there when you need them. Um.
28:00
Speaker 1: So these enthusiasts they record things, they record data, uh,
28:04
Speaker 1: to turn in like the time and the date, the colors,
28:07
Speaker 1: the latitude, and some might even make a little sketch
28:10
Speaker 1: of what they're seeing. Uh. And that really goes a
28:12
Speaker 1: long way to helping the scientists out and helping them understand, um,
28:17
Speaker 1: what our magnetic field is doing right now. And the
28:20
Speaker 1: scientists are like, we didn't ask for us. Get really
28:23
Speaker 1: appreciate the extra touch. You know, maybe watercolors nice, Maybe
28:28
Speaker 1: you put like a mint in the envelope to when
28:30
Speaker 1: you veil it off, it would be nice. Why not
28:32
Speaker 1: scientists love mints? Um apparently also, Chuck, something that was
28:39
Speaker 1: in this article is that you can there are aurora
28:42
Speaker 1: on other I'm just gonna say aurora's there are auroras
28:46
Speaker 1: on other UM planets too. Yeah, you know, I kind
28:50
Speaker 1: of wondered about that before I started researching, because, like
28:53
Speaker 1: you know, solar flares and winds don't just go towards Earth,
28:58
Speaker 1: and other planets have magnetic fields, so trurely this happens elsewhere,
29:02
Speaker 1: and it does. They've seen it on Jupiter Saturn. Uh yeah,
29:08
Speaker 1: Jupiter and Saturn, all right, but surely I mean, like
29:11
Speaker 1: if it's if The point is, if you have a
29:15
Speaker 1: magnetic field around the planet and an atmosphere around the
29:19
Speaker 1: planet that has ionic gases, and and anytime there's a
29:24
Speaker 1: solar flare that can reach it and UM create an
29:27
Speaker 1: electrical current in that magnetosphere, then you have all the
29:31
Speaker 1: conditions right for an aurora. I guess the colors will
29:33
Speaker 1: be different though, on Jupiter and Saturn, right, because it's different.
29:36
Speaker 1: That'd be awesome to see hydrogen and helium in their case.
29:39
Speaker 1: So I'm not sure that's a Chartrusse and brown brown
29:46
Speaker 1: aurora maybe not the best. So you want to take
29:48
Speaker 1: another break and then uh finish up. Yes, I have
29:51
Speaker 1: to have to wet down again. Okay, so chuck, um,
30:18
Speaker 1: we didn't say a lot of the uh, the the
30:22
Speaker 1: auroras that you see, um, they have they formed basically
30:26
Speaker 1: different shapes, like it can come in different well, different
30:29
Speaker 1: shapes around the poles. You've got the ovals, the rings,
30:34
Speaker 1: but there's other shapes they can take two and some
30:36
Speaker 1: of the more famous ones look like ribbons or curtains
30:40
Speaker 1: that kind of go basically from one horizon all the
30:43
Speaker 1: way to the other overhead. Uh and they going kind
30:47
Speaker 1: of this wavy river pattern. But then the lights stands
30:52
Speaker 1: upward into the atmosphere that it's got to be something
30:55
Speaker 1: to see, you know. Yeah, I mean, after researching this,
30:58
Speaker 1: I really like have a hankering to go see this
31:01
Speaker 1: in person one day, so I did too, and I
31:04
Speaker 1: still do. But I came across an article in The
31:07
Speaker 1: Independent and it was written by one of the Independence
31:10
Speaker 1: travel writers and they said that going to see the
31:14
Speaker 1: Northern Lights was the most disappointing travel experience they have
31:18
Speaker 1: ever had in their entire life. And she said that
31:21
Speaker 1: part of it is what had to do with the
31:24
Speaker 1: tour they went on. She said it sucked it was
31:26
Speaker 1: a terrible tour Ronnie worst tour guide ever in the
31:30
Speaker 1: Yelp review. Well, supposedly it was so this it was
31:33
Speaker 1: a um they called them a northern lights chase. But
31:37
Speaker 1: the chase consisted of sitting in their hosts living room
31:41
Speaker 1: and then every once a while someone would go to
31:43
Speaker 1: the window to see if the northern lights were out
31:45
Speaker 1: or not, and then they'd sit back down. Um, that
31:48
Speaker 1: was the chase. She said that there are that's a
31:51
Speaker 1: dumb thing to call it. Well, it's not like it's
31:54
Speaker 1: just over there. We just need to get a fast
31:56
Speaker 1: enough truck. And apparently there are those like the was
32:00
Speaker 1: kind of operations, and that's what she thought she was getting.
32:03
Speaker 1: So she was had and on the one hand, but um,
32:06
Speaker 1: she said, the actual northern lights that she saw were
32:09
Speaker 1: kind of grayish and looked a lot like keim or
32:13
Speaker 1: a contrail and or maybe even cigarettes smoke in the sky,
32:17
Speaker 1: kind of fog at night. Um. And then Ronie was
32:21
Speaker 1: just smoking. And then it wasn't. It wasn't until she
32:25
Speaker 1: saw the picture that the host took of them with,
32:28
Speaker 1: which requires like a long exposure, like ten to fourteen seconds.
32:32
Speaker 1: That's when the colors and all the amazing nous comes out.
32:36
Speaker 1: So everything you've seen in the pictures is from the
32:40
Speaker 1: long exposure, and apparently in person it's very rare that
32:44
Speaker 1: you see something that looks like the pictures. It looks
32:48
Speaker 1: very much different in real life apparently, and that disappointing.
32:52
Speaker 1: That's a huge bummer. But you just saved me like
32:54
Speaker 1: ten grand, so that that is really disappointing. That's a
32:59
Speaker 1: long exposure effect. Yes. For as far as the Independent
33:04
Speaker 1: writer um says that she said when she saw the picture,
33:08
Speaker 1: she was like, Oh, that's yeah, it's a it's a
33:10
Speaker 1: photo that we're seeing. She said, in real life they
33:12
Speaker 1: don't look like that. So the article you can read
33:15
Speaker 1: it yourself. Why seeing the Northern Lights was the most
33:17
Speaker 1: disappointing travel experience of my life, it was in the Independent.
33:22
Speaker 1: I'm gonna change my whisch then I don't want to
33:26
Speaker 1: pay to go on some dumb chase. I just want
33:30
Speaker 1: to happen upon them on a regular trip somewhere there
33:33
Speaker 1: you go. Then I'm already happy with Yeah, like Icelanders
33:36
Speaker 1: And actually she she makes the same exact point. She said,
33:39
Speaker 1: the rest of the trip was awesome. She said the
33:43
Speaker 1: the I think she was in Norway, and she said
33:46
Speaker 1: that the the just everything else about it was one
33:49
Speaker 1: of the best trips she's ever been on. It was
33:51
Speaker 1: the Northern Lights themselves that specifically stunk. And if you
33:57
Speaker 1: make that, you know, part of your tour, but not
33:59
Speaker 1: the whole reason you're going, you probably wouldn't be discipution
34:03
Speaker 1: to to visit the far north of Norway. Well, because
34:07
Speaker 1: I'm sure that's great on its own, you know, That's
34:09
Speaker 1: what she was saying. Yeah, I mean, gosh, I'm scrolling
34:12
Speaker 1: through the pictures now, it's amazing. That's uh. I thought
34:15
Speaker 1: that's what it looked like, right, That's what everybody thinks, apparently,
34:19
Speaker 1: but and sometimes I guess it does. But you are
34:22
Speaker 1: extraordinarily lucky if you're seeing the Northern Lights and it
34:26
Speaker 1: looks like that in person. From from what this lady
34:28
Speaker 1: is saying. Well, plus, if you go on one of those,
34:31
Speaker 1: there's nothing worse than feeling duped into and uh duped
34:36
Speaker 1: into spending a lot of money on a tour. Yeah,
34:38
Speaker 1: at some dude's house. Yeah, I'd like to see video.
34:42
Speaker 1: That would be more telling. Yeah, I can't can't just
34:46
Speaker 1: expose it like that with video, can you not? Well,
34:50
Speaker 1: I mean you can open up the exposure to get
34:52
Speaker 1: a two, get the video to look right, but it
34:57
Speaker 1: won't be just like a you know, it's not like
35:00
Speaker 1: open the exposure on uh, moving traffic at night with
35:04
Speaker 1: a photograph and you'll see like the dragging of the
35:06
Speaker 1: tail lights and stuff like that. Like it, it won't
35:09
Speaker 1: create some weird effect. I wonder if you use like
35:12
Speaker 1: a high speed filter it would do it? Or do
35:16
Speaker 1: you want low speed high speed filter? You know, obviously
35:21
Speaker 1: I'm I'm a professional photographer. Uh. Should we talk a
35:25
Speaker 1: little bit about the sound. Yeah, definitely. It makes a
35:28
Speaker 1: farting noise which is really interesting. Yea. And it kind
35:32
Speaker 1: of smells that would make it all more fun at least. Um. No,
35:35
Speaker 1: But there have long been people that um swore that
35:39
Speaker 1: it makes a sound um and not everyone because apparently
35:44
Speaker 1: and you know, someone actually found this out. It's a
35:48
Speaker 1: sound that only some people can hear sometimes. Yeah, And
35:52
Speaker 1: the conditions have to be super right for it, and
35:55
Speaker 1: there's very specific ones. And there's this one poor guy,
35:58
Speaker 1: his name is Unto kay Lane. He's finished, I belief.
36:03
Speaker 1: Um he's an acoustic acoustician, is there right? Yeah? Um
36:08
Speaker 1: from Finland who was on a camping trip, and I
36:11
Speaker 1: think two thousand and the Northern lights were just going
36:15
Speaker 1: off and going crazy, and he said he could hear
36:18
Speaker 1: like popping and crackling sounds and everyone said, well, that's
36:22
Speaker 1: because you were drunk, and he's like, no, I know
36:24
Speaker 1: for a fact I heard this. So he spent like
36:26
Speaker 1: the next fifteen years basically, um trying to capture the
36:31
Speaker 1: sounds of the Aurora borealis, and he finally was successful
36:36
Speaker 1: apparently in two thousand eleven. Yeah, and his whole deal was, UM, Well,
36:43
Speaker 1: when he was with his friends, first of all, he said,
36:45
Speaker 1: they had to be like completely still. It's not such
36:48
Speaker 1: a noise that you know, they're having a conversation, and
36:50
Speaker 1: they were like, oh, what's that like? They had to
36:53
Speaker 1: be dead silent, They had to not move in order
36:56
Speaker 1: to hear it. And then even within his group some
36:58
Speaker 1: people couldn't hear it at all because it just very
37:00
Speaker 1: low intensity. Right. But he's, like you said, been chasing
37:03
Speaker 1: that buzz ever since. And um, finally is he figured
37:10
Speaker 1: out I think he figured out the conditions first, right
37:13
Speaker 1: or did he do that? Did he back it in afterward?
37:16
Speaker 1: He he put two and two together. So we went
37:18
Speaker 1: out and he captured it one night, right the sounds,
37:22
Speaker 1: and then he went and looked up the UM like
37:25
Speaker 1: I guess the weather services report for that local area,
37:30
Speaker 1: and he figured out that what what he had been
37:33
Speaker 1: sitting under is called a thermal inversion layer where UM
37:39
Speaker 1: kind of warm at least compared to the air beneath
37:43
Speaker 1: it on the ground. UM warm air is kind of
37:46
Speaker 1: trapping the cold there below it, and as long as
37:50
Speaker 1: the conditions are super still, uh, and it's very cold,
37:54
Speaker 1: they're gonna stay separate, right, Yeah, it's gotta be clear,
37:57
Speaker 1: calm and cold, right, So would just be just an
38:02
Speaker 1: irregular aurora, Like you have to have a sub set
38:05
Speaker 1: of conditions to get this crackle noise exactly right. So UM,
38:09
Speaker 1: in the warm air, uh, the warm air layer, a
38:13
Speaker 1: lot of UM electrons are become charged and the cold
38:18
Speaker 1: are below it an opposite charge built, right, So you
38:21
Speaker 1: have this this um electrical charge just waiting to go
38:26
Speaker 1: off and turn into a current. And apparently it's the
38:29
Speaker 1: aurora above it that that causes the charge to actually
38:34
Speaker 1: turn into a current. Yeah, he was pretty surprised at
38:37
Speaker 1: first because he didn't just point a microphone. He had
38:39
Speaker 1: this array so he could triangulate exactly where the sound
38:42
Speaker 1: was coming from, and it was just two thirty ft
38:46
Speaker 1: above him was the sound and he was I don't
38:49
Speaker 1: know what the finished expression for holy crap is it's
38:53
Speaker 1: a oivey. I don't think so, but uh, that's what
38:58
Speaker 1: he said. And he was like, you know this is weird,
38:59
Speaker 1: this so low. Um, And that's when he came up
39:02
Speaker 1: with his theory and it does it check out fully?
39:05
Speaker 1: Or everybody said, you know, that's that's probably right. Yeah,
39:11
Speaker 1: they're like head the very least came up with definitive
39:14
Speaker 1: proof that this was um, the sound coming from it.
39:18
Speaker 1: But yeah, the fact that it was just overhead this
39:21
Speaker 1: in the thermal and vision layer explained how you could
39:24
Speaker 1: conceivably hear the Northern Lights. Amazing, Yeah, pretty amazing. You
39:30
Speaker 1: got anything else? I got nothing else. I'm just disappointed now, Yeah,
39:35
Speaker 1: for real, I'm disappointed in the Northern Lights and our
39:38
Speaker 1: episode on the Northern Lights. Uh if you yeah, man,
39:42
Speaker 1: the sun, anytime the sun comes into play, it's a curse,
39:45
Speaker 1: a pox on us. If you want to know more
39:48
Speaker 1: about the Northern Lights, go see him yourself. And if
39:50
Speaker 1: you have seen them in person and know us to
39:54
Speaker 1: be incorrect. Let us know because we would like our
39:56
Speaker 1: dreams back. Um. You can tweet to us at s
40:00
Speaker 1: SK podcast or josh um Clark. You can hang out
40:03
Speaker 1: with us on Facebook at Stuff you Should Know or
40:07
Speaker 1: Charles W. Chuck Bryant. You can send us an email
40:09
Speaker 1: the Stuff podcast at how Stuff works dot com. And
40:12
Speaker 1: as always, I started this one early which goes to
40:17
Speaker 1: show again, worst episode over, It's time for listener mail.
40:26
Speaker 1: That's right, I'm gonna call this. Uh well, it's just
40:31
Speaker 1: a nice email. Hey, guys, been a fan since two
40:33
Speaker 1: thousand and ten, when I was a freshman in college.
40:36
Speaker 1: I don't think I've ever written in though uh this
40:38
Speaker 1: entire time, have been an evangelist, but to no avail.
40:41
Speaker 1: That all change A few months ago I convinced the
40:43
Speaker 1: love of my life, Meredith, to give you guys a shot,
40:46
Speaker 1: And now she is fun too. She's an outstanding woman
40:49
Speaker 1: and mother and has courageously struck out a loan for
40:52
Speaker 1: a job offer she couldn't refuse. So now we live
40:54
Speaker 1: four hundred miles apart, and having your podcast to talk
40:57
Speaker 1: about keeps a conversation alive on day some weird feeling
41:00
Speaker 1: a bit down? Uh, I know, it's nice. In addition,
41:03
Speaker 1: I will also listen to you guys in the long
41:06
Speaker 1: car rides to visit her. There's a way to distract
41:08
Speaker 1: myself from my own excitement about getting to see her again,
41:11
Speaker 1: and it helps the time pass faster. Uh. I know
41:14
Speaker 1: it's not the first time someone's written to tell you
41:16
Speaker 1: the same thing, and I promise I would never be
41:18
Speaker 1: that listener. But I get it now, and when you
41:20
Speaker 1: find it true love, you just cannot help yourself. Sometimes
41:24
Speaker 1: this does get the coveted shout out. Tell Meredith to
41:27
Speaker 1: keep up the good work and Happy Mother's Day. Keep
41:30
Speaker 1: up the good work, guys. You were the first podcast
41:32
Speaker 1: I ever listened to and still my favorite. Sleep well
41:35
Speaker 1: tonight knowing that you are fostering love and real human
41:38
Speaker 1: connections out here in podcast land. That was a great email.
41:43
Speaker 1: That was nice. That is from Sam Martin and oh maha,
41:46
Speaker 1: he's a medical student and a bar trivia master. Thanks
41:49
Speaker 1: to us, he said, nice. Well, thanks a lot, Sam, Yes, Sam,
41:53
Speaker 1: and Mereth, thanks a lot Meredith for giving us a shot.
41:56
Speaker 1: We're glad it paid off. It reminds me of me
41:58
Speaker 1: and youm do long distance for a while. It can
42:01
Speaker 1: really really suck. Remember that you guys got through that
42:05
Speaker 1: like a champ, though we did like two chaps. Yeah,
42:08
Speaker 1: we've petted each other on the backs. If you want
42:11
Speaker 1: to get in touch with us, you already know how
42:13
Speaker 1: because I said it prematurely. Uh. And in the meantime
42:17
Speaker 1: you can hang out with us. Uh. It's stuff you
42:19
Speaker 1: should know. Dot com for more on this and thousands
42:27
Speaker 1: of other topics. Is it how stuff works? Dot com