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The shocking mystery of lightning explained · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Jorgey, you like looking up at the stars, right? Yeah,
0:11
Speaker 1: I love it. The stars are beautiful and brilliant, and
0:15
Speaker 1: it just makes you think about the universe. Next time
0:17
Speaker 1: you look with the stars, you might want to remember
0:19
Speaker 1: that the stars they can kill you. The stars that
0:22
Speaker 1: are billions of light years far away can kill me.
0:24
Speaker 1: That's right. Not just shooting stars, which are like meteors
0:27
Speaker 1: that could hit the earth and kill you, but the
0:29
Speaker 1: actual stars caused the death of about a hundred people
0:33
Speaker 1: a year, mostly men. It turns out mostly men. Is
0:36
Speaker 1: it because they're driving while they're trying to look at
0:38
Speaker 1: the stars? No, as usual, it turns out it's all
0:40
Speaker 1: about the particles. Hi, I'm more Hamming cartoon is and
1:00
Speaker 1: the creator of PhD comics. Hi, I'm Daniel. I'm a
1:03
Speaker 1: particle physicist, and I have not killed anybody this year
1:06
Speaker 1: or any other year. Well that's good. That's always a
1:09
Speaker 1: good thing to put in your resume. I like just
1:12
Speaker 1: coming out denying that initially, Like nobody asks you, but
1:15
Speaker 1: I just want you to know, I'm a particle physicist,
1:17
Speaker 1: but I haven't killed anybody. Is that how you introduce yourself?
1:21
Speaker 1: Every time? Hi, I'm Daniel and today. I haven't killed anybody.
1:25
Speaker 1: Day ain't over yet, right now. That's how I introduced
1:28
Speaker 1: myself to my my girlfriend's father that you know my
1:32
Speaker 1: girlfriend now wife's father. I'm a particle physicist. Don't worry,
1:35
Speaker 1: I haven't killed anybody now. Actually he's a he's also
1:38
Speaker 1: a physicist. So as soon as he heard that I
1:39
Speaker 1: was a physicist, he was like, this is the one. Well,
1:42
Speaker 1: welcome to an electrifying episode of Daniel and Jorge Explained
1:46
Speaker 1: the Universe, a production of I Heart Radio. That's right,
1:49
Speaker 1: in which we try to unmask the mysteries of physics
1:52
Speaker 1: out there in the universe and right here on Earth.
1:55
Speaker 1: Let's try we try to uncover the shocking truth about
1:59
Speaker 1: the world around you, and uh try to do it
2:02
Speaker 1: all in a quick flash. That's right. We try to
2:04
Speaker 1: charge up your physics batteries and overload your bad joke capacity.
2:11
Speaker 1: That's right. And today we're talking about a topic which
2:14
Speaker 1: is a particular interest to me, um, and I think
2:17
Speaker 1: of interest to everybody who's looked up at the sky
2:20
Speaker 1: during a thunderstorm. Yeah, it's something that I think makes
2:23
Speaker 1: everybody curious. Since you're a little kid, you're probably wonder
2:26
Speaker 1: what is going on with that, and it's something that
2:28
Speaker 1: people have been wondering about for thousands and thousands of years.
2:31
Speaker 1: You know, it's one of the earliest natural phenomena that
2:34
Speaker 1: inspired religion. You know, people give this power to the
2:37
Speaker 1: gods because it seems so dramatic. So to be on
2:40
Speaker 1: the program, we are going to be talking about lightning.
2:48
Speaker 1: What is lightning, what causes lightning? And where is the
2:52
Speaker 1: mystery in it? Because apparently there are still unanswered questions
2:56
Speaker 1: about lightning. That's right. One of my favorite trends in
2:59
Speaker 1: sort of human ulture is seeing things that are obviously weird, fascinating,
3:03
Speaker 1: amazing the humans used to describe using religion, right, or mythology,
3:08
Speaker 1: and then science slowly sort of pieces that together the
3:11
Speaker 1: mystery and reveals the physics behind it. You know, Oh,
3:14
Speaker 1: it turns out it's this. It turns out it's that. Right.
3:17
Speaker 1: One of the most amazing natural phenomena to witness is lightning. Right,
3:21
Speaker 1: And there's of course the a nice long arc of
3:23
Speaker 1: history of understanding lightning. But it turns out that lightning
3:26
Speaker 1: still has a lot of mysteries. There's still a little
3:29
Speaker 1: bit of magic and mythology behind it, right until physics
3:32
Speaker 1: kills it all until physicists become mythical themselves. Right. Yeah,
3:38
Speaker 1: but lightning, I guess you know, it's such a tangible,
3:41
Speaker 1: you know, phenomenon. It's so visually striking too, write I mean,
3:44
Speaker 1: not just because it strikes the earth, but you know,
3:47
Speaker 1: it's like it's seeing this giant column of light in
3:50
Speaker 1: the middle of a storm. It's just impressive and it
3:52
Speaker 1: makes you think, man, there must be some kind of
3:55
Speaker 1: deity or god throwing that down. It certainly is awe inspiring. Right,
4:00
Speaker 1: You look at that and you think, wow, nature or
4:02
Speaker 1: the universe or something out there is so much more
4:05
Speaker 1: powerful than me. It seems like such an impressive display,
4:08
Speaker 1: you know, and it is impressive, you know, like a
4:11
Speaker 1: single lightning strike has a billion jewels of energy in it,
4:16
Speaker 1: a billion, right and billion once one lightning strike a
4:20
Speaker 1: billion jewels. Yeah, And how much is that relative to like, um,
4:24
Speaker 1: a light bulb? Yeah, well, you know, to calibrate, you
4:28
Speaker 1: and your household probably use about thirty seven billion jewels
4:33
Speaker 1: a year, So in a week your house uses a
4:36
Speaker 1: little less than a billion jewels of energy. So billion
4:39
Speaker 1: jewels of energy is like enough to power a house
4:41
Speaker 1: for a week. Now, is that with my kids using
4:44
Speaker 1: the iPad all the time or not using the iPad.
4:46
Speaker 1: So I stood outside your house for this episode and
4:48
Speaker 1: I measured your house is electricity usage. So this is
4:52
Speaker 1: very specific to you. I heard the rock the actor
4:55
Speaker 1: his punch has is about a four hundred jewels. So
5:01
Speaker 1: you know, a normal person's punches, you know, tens of jewels,
5:04
Speaker 1: but like a really strong professional can get to the
5:06
Speaker 1: hundreds of jewels. But you know that's just hundreds of jewels.
5:10
Speaker 1: That means that a lightning strike is like getting punched
5:12
Speaker 1: by the rock two and a half million times. So
5:16
Speaker 1: pretty serious stuff. Yeah, so it's something that it's been
5:19
Speaker 1: in mythology for a long time, and it's it seems
5:22
Speaker 1: like that it's something that signs still hasn't captured quite
5:26
Speaker 1: in a bottle, right, there's still some mysteries about it. Yeah,
5:28
Speaker 1: it turns out that there's some deep connections between lightning
5:32
Speaker 1: and particle physics, but we'll dig into that. Um. But
5:35
Speaker 1: I was wondering, you know, what do people know about lightning?
5:38
Speaker 1: Is people? Do people think lightning as well understood? Does
5:40
Speaker 1: everybody out there have a good model for lightning in
5:42
Speaker 1: their head or most people still just like awe inspired
5:45
Speaker 1: and dumb struck and have no idea what's causing it. So,
5:48
Speaker 1: as usual, Daniel went out and asked people on the
5:50
Speaker 1: street or sometimes at reports if they knew. I have
5:55
Speaker 1: been doing a lot of traveling this summer, so I've
5:56
Speaker 1: been just taking the opportunity to ask people all around
5:59
Speaker 1: the world random questions about physics. So as usual, Daniel
6:02
Speaker 1: went out and asked people in the street did they
6:04
Speaker 1: knew what lightning is and what causes it? So before
6:08
Speaker 1: you hear these answers, think about it for a second.
6:11
Speaker 1: If someone asked you on the street what lighting was,
6:13
Speaker 1: what would you answer. Here's what people had to say.
6:17
Speaker 1: I just know it's like a ray of like of
6:21
Speaker 1: like shooting really fast and then it hits a point.
6:24
Speaker 1: It's like an energy that hits from one point to another. Essentially,
6:28
Speaker 1: charge particles moving between differential charge and different positions, and
6:31
Speaker 1: they're moving for one place to another. Um you know,
6:35
Speaker 1: usually you see it between clouds in the sky. Has
6:38
Speaker 1: something to do with like a static electrics trusty charge.
6:42
Speaker 1: I think that builds up as maybe the water molecules
6:45
Speaker 1: are moving in the cloud. I don't think something like that.
6:47
Speaker 1: It's a charge difference between the ground of the clouds.
6:53
Speaker 1: It's like the spontaneous ionization of air like excitement of
6:57
Speaker 1: park like protons and the clouds, and then this like
7:00
Speaker 1: a tracer beam to the ground and once being instaground
7:03
Speaker 1: and lightningtially strikes to know. Yeah, lightning is just the
7:06
Speaker 1: breakdown of gas or ionizing of gas and allowing electrons
7:10
Speaker 1: to float through high voltages. All right, people had long
7:13
Speaker 1: answers for these people have thought about lightning. Lightning is
7:16
Speaker 1: definitely something that's inspired physics thoughts in people's minds. Right,
7:20
Speaker 1: They look at that and they wonder what is it?
7:22
Speaker 1: And I guess they get inspired or google a little
7:24
Speaker 1: bit or read about it. But there's some knowledge about
7:27
Speaker 1: lightning out there, for sure. I was impressed. It seems
7:29
Speaker 1: very more binary than usual. Some people are like, I
7:32
Speaker 1: have no idea, I'm not really sure, but some people
7:34
Speaker 1: were like, oh, it's a charge and electricity and clouds
7:37
Speaker 1: and ground. Yeah, And this time people who have very
7:40
Speaker 1: specific ideas have pretty specific and mostly correct ideas. Right.
7:44
Speaker 1: Didn't get a whole lot of people pontificating totally off topic.
7:47
Speaker 1: So that was pretty impressive. What do you think that
7:49
Speaker 1: comes from? Do you think, um, you know, kids TV
7:52
Speaker 1: explains lightning or people something that maybe in high school
7:55
Speaker 1: people here about. Yeah, I don't know. I think it
7:58
Speaker 1: has to do with the immediacy of it. Right. Lightning
8:00
Speaker 1: is something that's right there in most people's lives, and
8:03
Speaker 1: so it's not like the Higgs boson or other crazy stuff.
8:07
Speaker 1: It's it makes people wonder and they want answers. I
8:10
Speaker 1: think the good news is that nobody said Zeus throwing
8:15
Speaker 1: down and bolts. I thought you were a favor of
8:19
Speaker 1: mysticism and magic, right, so now now you're cheering physics
8:22
Speaker 1: on for destroying the old gods mooney or something. Uh.
8:30
Speaker 1: I think it's interesting, um that you said earlier, most
8:35
Speaker 1: lightning strikes are happened to hid men. Yeah, that's right.
8:39
Speaker 1: About a hundred people every year are killed by lightning,
8:42
Speaker 1: and eight out of a hundred are men. I think
8:44
Speaker 1: that is really quite fascinating. Um. Yeah, what what used
8:48
Speaker 1: to that? It's so that that is so weird. Yeah.
8:51
Speaker 1: I don't think it has to do with like the
8:53
Speaker 1: physiology of men, or the height of men, or you know,
8:58
Speaker 1: the volume of their hair, or or electrical you know,
9:01
Speaker 1: their capacity to conduct electricity or anything might have to
9:05
Speaker 1: do with where men are. You know, maybe they're out more,
9:07
Speaker 1: or they're climbing poles more or something where they're doing
9:11
Speaker 1: stupid stuff in lightning storms more. That sounds about right,
9:16
Speaker 1: Or I think this is just proved that maybe Zeus
9:19
Speaker 1: is a woman. I think all this time, Yeah, I was.
9:24
Speaker 1: I was totally floored by that fact. That was like.
9:27
Speaker 1: And the other thing that's interesting is that lightning doesn't
9:30
Speaker 1: just strike men more, but it's not equally distributed around
9:33
Speaker 1: the world. Right. There's some areas around the world where
9:35
Speaker 1: lightning over almost never happens in other areas where it's
9:38
Speaker 1: really common. It's just where it happens more, not just
9:41
Speaker 1: where it hits people. Yeah, just in general, where it
9:43
Speaker 1: strikes the ground, like in Central Africa and in the
9:46
Speaker 1: Himalayas and in Florida in the US, you get a
9:49
Speaker 1: lot of lightning, but in other places, like in Europe,
9:51
Speaker 1: is much much, much less lightning. I think that's just
9:54
Speaker 1: um the universe punishing Florida for it's roll into political
10:00
Speaker 1: for having a bunch of weird dudes in it, right,
10:02
Speaker 1: And that's because of the weather. There's just more weather
10:04
Speaker 1: activity over those places. Or you need wide open fields
10:08
Speaker 1: what what's going on? Yeah, well we'll talk about it
10:11
Speaker 1: when we dig into how lightning is formed. But you
10:13
Speaker 1: need just the right weather conditions. Florida, for example, is
10:16
Speaker 1: very moist and has a lot of storms, and so
10:18
Speaker 1: you have the conditions to spark lightning more often than
10:22
Speaker 1: you do in other drier places. So let's break it down. Well,
10:25
Speaker 1: let's start with what is lightning Like if you had
10:27
Speaker 1: to define lightning, how would you describe it? Yeah, so
10:30
Speaker 1: lightning a common misconception that lightning is fire, right, But
10:33
Speaker 1: it's not. Lightning is electricity, right, it's it's actually a
10:38
Speaker 1: glowing tube of plasma. Remember the states of matter. You
10:42
Speaker 1: have solid liquid gas, and then plasma, the least often
10:46
Speaker 1: discussed state of matter. That's a gas has so much
10:50
Speaker 1: energy that the atoms have become ionized. The electrons have
10:53
Speaker 1: gotten pulled off of the positive nuclei, and so it
10:56
Speaker 1: conducts electricity. So it's the gas that conducts electricity usually glows.
11:01
Speaker 1: That's like what's inside fluorescent light bulbs. The atoms break down,
11:04
Speaker 1: they like, they just have so much energy they break apart.
11:08
Speaker 1: The atoms exactly. The electrons have been torn off of
11:11
Speaker 1: the positive nuclei and plasma is not so weird. They
11:14
Speaker 1: can't stay start to the nucleus. Yeah, like inside a
11:17
Speaker 1: fluorescent light bulb. That's what you have is a plasma.
11:19
Speaker 1: You have a gas that's been ionized and it's glowing, right,
11:23
Speaker 1: And so that's what lightning is. It's just a long
11:25
Speaker 1: arc of conducting gas, right. Essentially, electricity is flowing through it.
11:31
Speaker 1: It's just a giant fluorescent tube. Yeah, it's a giant
11:34
Speaker 1: fluorescent tube. Essentially, the air has been turned into a wire. Right.
11:38
Speaker 1: Normally air doesn't conduct electricity, it's an insulator, right. But
11:42
Speaker 1: if you get enough positive charges on one side and
11:45
Speaker 1: negative charges on the other side, then the force is
11:48
Speaker 1: so strong that that it breaks apart the atoms and
11:51
Speaker 1: turns it into a conductor. And that's what happens with lightning.
11:55
Speaker 1: The glow that you're seeing, the flash, that's just the
11:57
Speaker 1: electricity flowing down this giant fluorescent tube. Yeah, there's so
12:02
Speaker 1: much energy in there. Stuff is vibrating and when it's
12:04
Speaker 1: vibrating has so much energy. It's also giving off light. Right.
12:07
Speaker 1: It's a it's getting that energy and then it's trying
12:10
Speaker 1: to emit that energy. That's what the glow is. The
12:12
Speaker 1: ions haven't lost all of their electrons, right, They also
12:15
Speaker 1: absorbed some other energy, and those electrons bounce up and down.
12:18
Speaker 1: When the electrons go down, they give off a photon.
12:20
Speaker 1: So that's what you're seeing. That's the glow from the
12:23
Speaker 1: plasma I see. But is it like a flow of electrons? What?
12:26
Speaker 1: What are you? How do you how do you think
12:28
Speaker 1: about it? Is it electrons flowing from the clouds to
12:30
Speaker 1: the ground. Is that a good way to think about it? Yeah,
12:32
Speaker 1: it's actually really fascinating how it happens. You have a
12:36
Speaker 1: positive charge on the ground and a negative charge on
12:40
Speaker 1: the bottom of the cloud, all right, So you have
12:42
Speaker 1: this separation, and then the electrons they leave the bottom
12:46
Speaker 1: of the cloud and they explore the air. They move
12:49
Speaker 1: out and they break into these forks like the step structure,
12:53
Speaker 1: and they're looking for a path to the ground. And
12:55
Speaker 1: they when they find the path of least resistance to
12:58
Speaker 1: the ground, the one with where it's easiest to rip
13:01
Speaker 1: the electrons off the atom, right, they make a connection
13:03
Speaker 1: to the ground. Then you basically have this electrical connection
13:07
Speaker 1: and a huge pulse of energy then travels up from
13:10
Speaker 1: the ground to the cloud. And that's what you actually
13:13
Speaker 1: see and you see a bolt of lightning, that's what
13:16
Speaker 1: you're seeing. You're seeing stuff come up from the ground,
13:19
Speaker 1: not the electrons coming down to the ground. That's right.
13:22
Speaker 1: What you're seeing is the pulse that goes up this
13:25
Speaker 1: this first part of lightning. It's also really quick, but
13:27
Speaker 1: it's much less bright because it's just electrons finding the path.
13:31
Speaker 1: Once they make the connection, then all of a sudden,
13:34
Speaker 1: there's this huge opportunity, right, you have this enormous charge
13:37
Speaker 1: difference between the ground and the cloud. It's desperate, desperate
13:41
Speaker 1: to connect, right, and as soon as there's a connection,
13:44
Speaker 1: then it all rushes through there. But it starts where
13:46
Speaker 1: the connection is formed, which is at the ground, and
13:49
Speaker 1: then the pulse goes up to the ground, up to
13:52
Speaker 1: the cloud like half the speed of light. You're saying
13:54
Speaker 1: that the glow starts from the ground, but actually, but
13:58
Speaker 1: the whole thing is it's a it's a trons coming
14:00
Speaker 1: down from the cloud to the ground. That's right. Whenever
14:03
Speaker 1: you have a circuit and you have charges moving, it's
14:05
Speaker 1: always electrons that are moving because they're much lighter than
14:08
Speaker 1: the nuclei, the positively charged nuclei, so it's always about
14:11
Speaker 1: negative charges moving and in this case, you have electrons
14:13
Speaker 1: flowing down to the ground, right, But the electrons find
14:18
Speaker 1: the path down to the ground, and then the pulse,
14:20
Speaker 1: the actual movement of the electricity, starts at the ground
14:24
Speaker 1: and then it works its way back up to the cloud.
14:26
Speaker 1: You're saying that the plasma ification of the air starts
14:30
Speaker 1: at the ground, Yeah, because that's when that's when the
14:33
Speaker 1: connection is first made. I think about this like the
14:35
Speaker 1: way water is always trying to flow down to the ground.
14:38
Speaker 1: So imagine you had like a huge bag of water
14:41
Speaker 1: or something. It's like looking for a hole in the
14:44
Speaker 1: bottom of the bag. It's trying to find its way out, right.
14:46
Speaker 1: We're trying to find the weakest spot in the bag
14:49
Speaker 1: and keep pouring water into the bag. And eventually the
14:52
Speaker 1: weakest spot in the bag is gonna pop. And when
14:54
Speaker 1: that happens, boom, all the water is going to rush out, right, Like,
14:57
Speaker 1: that's what happens when you pop a water balloon. Right.
15:00
Speaker 1: A water balloon doesn't explode everywhere at once, explodes in
15:03
Speaker 1: one tiny point and then the rest of it follows.
15:06
Speaker 1: So you're saying, like, as soon as it touches the ground,
15:08
Speaker 1: the first electrons, then then the rushing of the electrons
15:11
Speaker 1: happens first at the ground, and then the rushing kind
15:14
Speaker 1: of propagates up. And so that's why, like, if you
15:17
Speaker 1: look at high speed high speed movie of lightning, it
15:20
Speaker 1: looks like it's actually moving up from the ground. That's right, exactly,
15:23
Speaker 1: because when the bottom makes the connection with the electrons
15:26
Speaker 1: first touched the ground, the top doesn't yet know. Right,
15:29
Speaker 1: No information in the universe travels faster than the speed
15:31
Speaker 1: of light. Nothing is instantaneous. So the connection is first
15:34
Speaker 1: made at the bottom, and the rushing, the glowing the
15:37
Speaker 1: plasmifications start there and then moves very rapidly up to
15:40
Speaker 1: the clouds. And I only learned this when I actually
15:43
Speaker 1: pointed a high speed camera at a lightning strike. You
15:47
Speaker 1: said you found this out when you pointed a camera
15:49
Speaker 1: at a lightning Yeah. One of my first science summer
15:53
Speaker 1: jobs was working with a plasma physics group. They're the
15:57
Speaker 1: kind of folks that build fusion reactors, and they would
16:00
Speaker 1: inject fuel into these reactors and wanted to see what happened.
16:03
Speaker 1: So they bought a hugely expensive super high speed camera
16:07
Speaker 1: that could take like fifteen thousand frame digital pictures a
16:11
Speaker 1: second at the time. This is in the nineties. That
16:14
Speaker 1: was super duper high tech. And but then the fusion
16:17
Speaker 1: reactor wasn't working, and so we thought, well, let's test
16:20
Speaker 1: it on something else. So the scientist I was working with,
16:23
Speaker 1: Glenn Wharton, Um he lived in Um. You guys were like,
16:26
Speaker 1: we need five point one exactly. We're like our our
16:31
Speaker 1: fusion reactor. We were like, what's a good reliable source
16:36
Speaker 1: of plasma? And in northern New Mexico every afternoon there's
16:40
Speaker 1: a thunderstorm. It's crazy. It's like sunny skies at two
16:43
Speaker 1: o'clock to fifteen, nothing and then all of a sudden
16:46
Speaker 1: to twenty or so huge thunderstorm, pouring rain for about
16:50
Speaker 1: fifteen minutes, and then blue skies again pretty reliably. So
16:54
Speaker 1: we took the camera to his garage and we set
16:56
Speaker 1: it up and we just sort of pointed in a
16:58
Speaker 1: random direction and turned it on and boomed the huge
17:02
Speaker 1: lightning strike right when we turned it on, and we
17:04
Speaker 1: got this incredible footage and you could see the lightning
17:08
Speaker 1: breaking out, stepping down to the ground, and then this
17:11
Speaker 1: huge pulse that went up. And so we wrote a
17:14
Speaker 1: paper science paper that was essentially like, look at this
17:17
Speaker 1: awesome footage we got, and that was it Nobody else
17:21
Speaker 1: had done it before. No, it was the first one
17:23
Speaker 1: as far as I'm aware of. And so we published
17:26
Speaker 1: it and it's got six citations so far. That's uh,
17:33
Speaker 1: that's a lot for particle physics, isn't it? Plasma physics?
17:36
Speaker 1: And um Interestingly, three of those citations came in the
17:39
Speaker 1: last few years, so it's gathering some attention. You know,
17:41
Speaker 1: maybe it's gonna be one of these papers that gets
17:43
Speaker 1: no citations and then changes the world. Wow. So when
17:47
Speaker 1: they say of lightning strikes are men, they really just
17:50
Speaker 1: mean like male physicists think it's a good idea to
17:54
Speaker 1: go out into the store to take pictures. That's right now.
17:58
Speaker 1: We were safely ensconced in in his garage. But it
18:01
Speaker 1: was a pretty awesome experience. I had never seen lightning,
18:04
Speaker 1: um in slow motion. It was pretty exhilarating. Cool. That
18:07
Speaker 1: sounds really cool. So that's lightning, and so let's get
18:10
Speaker 1: into what causes lightning and let's get into where the
18:14
Speaker 1: mystery is that scientists haven't figured out. But first let's
18:19
Speaker 1: take a quick break. All right, we talked about what
18:34
Speaker 1: lightning is. It's essentially giant fluorescent tube. So it's like
18:37
Speaker 1: a giant. It's like the neon sign of nature. That's right.
18:41
Speaker 1: It's sort of like a giant fluorescent tube and you
18:43
Speaker 1: can see sort of many lightning all the time. Like
18:45
Speaker 1: do you ever get static electricity? You know, you like
18:47
Speaker 1: rub your feet across carpet um essentially build up a
18:51
Speaker 1: bunch of charge and then if you touch something, you
18:53
Speaker 1: feel a little zapp Right, if you look carefully, you
18:55
Speaker 1: can see a little arc of electricity that's sort of
18:58
Speaker 1: like mini lightning from your fingertips, like you are mini
19:01
Speaker 1: Zeus in that case. And it's the same thing happening
19:04
Speaker 1: is that electrons from my finger are jumping over to
19:07
Speaker 1: the door knob, which ionizes the air between there, and
19:12
Speaker 1: that's what causes this part exactly. And it only happens
19:15
Speaker 1: when you get close enough because it's easier to ionize
19:18
Speaker 1: a smaller amount of air. Either you can get closer
19:21
Speaker 1: or you can increase the amount of power and then
19:23
Speaker 1: you get a bigger arc. So anyone can shoot plasma
19:26
Speaker 1: from their finger, that's right, yeah, exactly. You might not
19:30
Speaker 1: be as powerful as the rock, but you can shoot
19:32
Speaker 1: lightning bolts from your fingertips, a little tiny one millimeter
19:37
Speaker 1: lightning bolts but still it's plasma at your fingertips. And
19:41
Speaker 1: the way that you do that here on Earth right
19:43
Speaker 1: is like you're rubbing your feet against the carpet. Or
19:45
Speaker 1: you can do this in a demonstration if you take
19:47
Speaker 1: like a glass rod and you rub it with a
19:49
Speaker 1: silk cloth or something. And essentially what you're doing there
19:52
Speaker 1: is you're stripping electrons. You're there's some complicated physics of
19:56
Speaker 1: the friction there, but basically you're pulling the electrons off
19:59
Speaker 1: of atoms and building up a charge. So you like
20:02
Speaker 1: you rub two atoms together and the electrons just fly
20:05
Speaker 1: off and but don't need come back right away. It depends,
20:09
Speaker 1: right if there's something to separate them. And so in
20:11
Speaker 1: the cloud, people are not exactly sure how this happens,
20:14
Speaker 1: but they think that there's some complex interaction between sort
20:18
Speaker 1: of semi frozen pellets of water and crystals of ice
20:22
Speaker 1: that bump up against each other, and one of them
20:24
Speaker 1: is lighter than the other, and they bump up against
20:26
Speaker 1: each other and then they have different reactions to wind
20:29
Speaker 1: and gravity, and so they get separated, and that's how
20:31
Speaker 1: you get this charge build up inside the cloud. Essentially,
20:35
Speaker 1: it's friction between you know, crystals of ice and semi
20:38
Speaker 1: frozen drops of water. Okay, wait a minute, you're saying,
20:40
Speaker 1: what do you mean it's not well understood. We don't
20:42
Speaker 1: know exactly what causes lightning, but we we skipped over
20:46
Speaker 1: that and went straight for the Higgs boson and the
20:49
Speaker 1: mental particles of nature. Yeah, exactly. It turns out there
20:53
Speaker 1: are huge mysteries right here on Earth. Like people have
20:56
Speaker 1: tried to build models of what's going on inside the
20:58
Speaker 1: cloud and they think, Okay, if you're going to get lightning,
21:01
Speaker 1: you need to have a huge charge difference, right. I mean,
21:05
Speaker 1: it takes a pretty good amount of of charge just
21:07
Speaker 1: to get that little zapp from your finger to the
21:09
Speaker 1: door knob. Now imagine crossing like five kilometers from the
21:13
Speaker 1: ground to the cloud. You need a huge charge difference, right,
21:17
Speaker 1: So they have some idea about how much this happens
21:20
Speaker 1: and how these things build up. Um, And then they
21:23
Speaker 1: went out and they measured it. They shot these rockets
21:26
Speaker 1: into clouds to measure the electric fields to see, like
21:29
Speaker 1: are the electric fields actually big enough to make lightning?
21:32
Speaker 1: And they found out that they're not. Right, Like, if
21:35
Speaker 1: you shoot rockets up in into clouds, you measure pretty
21:38
Speaker 1: strong electric fields, but not nearly strong enough to create lightning,
21:42
Speaker 1: not nearly strong enough to to cross this huge gap
21:45
Speaker 1: of an insulator from the cloud to the ground. Wait,
21:47
Speaker 1: so you do get a big accumulation of electrons up
21:52
Speaker 1: in the clouds, but you're saying it's not big enough
21:54
Speaker 1: to cross over to the ground. Yeah, it shouldn't happen.
21:58
Speaker 1: Lightning shouldn't happen. Like you measure the electric field inside
22:02
Speaker 1: a cloud, there's not enough of an electric field there.
22:05
Speaker 1: The charge difference is not big enough to cause lightning.
22:08
Speaker 1: You would need much more accumulation of electrons to actually
22:12
Speaker 1: cause the spark exactly. We understand pretty well the physics
22:16
Speaker 1: of of ionizing gas, right, We know what error is
22:19
Speaker 1: made out of. We know how the water in their works.
22:21
Speaker 1: We know how much electricity, how much voltage difference it
22:25
Speaker 1: takes to create an arc. And people can do these
22:27
Speaker 1: studies in the lab. It's not difficult, right. You mix
22:30
Speaker 1: various gases together to simulate air, You add humidity, You
22:34
Speaker 1: can stimulate the situation pretty exactly, and then you can
22:36
Speaker 1: put a charge difference across and you can see when
22:39
Speaker 1: does the air breakdown? How much charge difference does it
22:42
Speaker 1: take to create this bolt, and so we know when
22:45
Speaker 1: that happens, and we measure in the cloud and there's
22:47
Speaker 1: not enough charge difference, so we don't understand what makes
22:52
Speaker 1: lightning start. I feel like there's two mysteries here. One is,
22:55
Speaker 1: you don't really understand We don't really understand what causes
22:59
Speaker 1: the frick shin two and the rubbing of the to
23:02
Speaker 1: create the electrons to a bunch up. And also we
23:06
Speaker 1: don't know what actually makes it come down to earth.
23:10
Speaker 1: That is that sort of right, there's two mysteries. That's right,
23:12
Speaker 1: there's two mysteries there. One is you know what process
23:15
Speaker 1: exactly is causing this charge difference. And people have these
23:18
Speaker 1: models about the way the water pellets are ub up
23:21
Speaker 1: against each other um, and that partially explains it. But
23:24
Speaker 1: there's still mysteries there. But I think the bigger mystery,
23:27
Speaker 1: the more fascinating one is you know, you measure the
23:29
Speaker 1: electric field, Like whether or not you understand how the
23:31
Speaker 1: electric field gets there, you measure it and you see
23:34
Speaker 1: that it's not strong enough to make lightning. So why
23:37
Speaker 1: do we get lightning? Because obviously we get lightning, right,
23:40
Speaker 1: Obviously it's some old white dude with a white beard
23:43
Speaker 1: throwing it down striking mortals. And this is where the
23:47
Speaker 1: particle physics comes in, because people discovered that when you
23:51
Speaker 1: get a lightning strike, is actually a huge amount of
23:53
Speaker 1: radiation in those clouds, especially X rays lightning strikes. And
23:58
Speaker 1: people went out there with the like ray sensors and
24:02
Speaker 1: there's a big amount of X ray. You're gonna say,
24:04
Speaker 1: X rayometers, X X ray, X ray matics. Yeah, people
24:11
Speaker 1: hadn't thought to do this right there. People hadn't fought
24:14
Speaker 1: until very recently. This is like ten years ago. People
24:16
Speaker 1: hadn't thought to measure like is there radiation inside a thundercloud?
24:21
Speaker 1: And then they built these devices to measure X rays
24:23
Speaker 1: and other kind of particle radiation, and it turns out
24:26
Speaker 1: there's a huge amount of radiation, especially X ray radiation
24:30
Speaker 1: that's created when there's a lightning strike. And that's not normal.
24:32
Speaker 1: Like when you have this plasma and you have these
24:35
Speaker 1: ions and all this physics going on, that's not normal
24:39
Speaker 1: to just admit and give out X rays. The models
24:42
Speaker 1: of of plasmas do not suggest that you should get
24:45
Speaker 1: this much X rays. So then people thought, well, maybe
24:48
Speaker 1: it's not the lightning that's causing the X rays. Maybe
24:51
Speaker 1: it's the other way around. Maybe something is happening which
24:55
Speaker 1: generates all this radiation and that's what causes the lightning.
24:58
Speaker 1: So one of the ideas people have now is maybe
25:02
Speaker 1: it's particles from space, right, also known as cosmic rays
25:08
Speaker 1: um X rays are caused by rays of energy from space. Yeah,
25:15
Speaker 1: so some star somewhere a jillion years ago goes supernova,
25:19
Speaker 1: flings out a super high energy particle, right, which flies
25:23
Speaker 1: across the universe, enters the Earth's atmosphere. And what happens
25:26
Speaker 1: when a huge high energy particle enters your's atmosphere is
25:29
Speaker 1: it creates a shower of radiation. Now, if that happens
25:33
Speaker 1: to hit a cloud, this is a theory, right, if
25:35
Speaker 1: that happens to hit a cloud that has a big
25:38
Speaker 1: charge difference, not enough to cause lightning, but a pretty
25:40
Speaker 1: good charge difference, it can give it the kick it
25:43
Speaker 1: needs to spark that lightning to push the electrons down
25:46
Speaker 1: into the ground exactly. That can give them that boost
25:49
Speaker 1: to get sort of over the hump. So the model
25:51
Speaker 1: is like, you've got all these clouds, they're primed to spark, right,
25:55
Speaker 1: they don't have enough energy to spark and actually cause lightning,
25:57
Speaker 1: and then a particle from space how happens to hit them?
26:00
Speaker 1: And said, Ben basically starts the lightning fire. So you're
26:03
Speaker 1: saying that lightning is caused by something in the heavens.
26:08
Speaker 1: Oh my gosh, outside of this earth, beyond beyond our
26:13
Speaker 1: our our existence here. It's not mythological, but it is extraterrestrial. Yes,
26:18
Speaker 1: that's the theory, right. The amazing thing is an alien
26:23
Speaker 1: I have on the on the tape here now Daniel
26:26
Speaker 1: Zeus is an alien mostly killing men. Yes, exactly, that's
26:29
Speaker 1: physics has taught us. No, we don't know this right.
26:32
Speaker 1: This is an active area of investigation where the most
26:35
Speaker 1: amazing thing to me is that we still don't understand lightning,
26:38
Speaker 1: Like these are pretty basic questions. Until recently, we didn't
26:41
Speaker 1: realize like there's a lot of radiation inside a cloud,
26:44
Speaker 1: Like an airliner that flies through a thunderstorm is actually
26:48
Speaker 1: exposing its passengers to more radiation, right, Because it turns
26:52
Speaker 1: out there's a lot of radiation inside these thunderstorms. There's
26:55
Speaker 1: a huge amount of stuff that we just don't understand
26:57
Speaker 1: going on inside, and we don't have time to dig
27:00
Speaker 1: new to it today. But there's we're just talking about
27:02
Speaker 1: one kind of lightning like cloud to ground, this cloud
27:06
Speaker 1: to cloud lightning, this inter cloud lightning. There's all sorts
27:10
Speaker 1: of crazy kinds of lightning, like sprites and elves and
27:13
Speaker 1: all sorts of crazy stuff that nobody understands at all.
27:16
Speaker 1: I feel like maybe you guys have the large hadron colliders,
27:18
Speaker 1: you just like hit the pause button and um, just
27:22
Speaker 1: for a week, all those three thousand scientists, you maybe
27:25
Speaker 1: focus on this question first. That's like thinking that, like
27:29
Speaker 1: science can only do one thing at a time, right,
27:31
Speaker 1: you know, science is multifacet and we've got folks interested
27:34
Speaker 1: in lightning. We have folks interested in, you know, how
27:37
Speaker 1: ducks procreate. We got folks interested in the Higgs boson.
27:40
Speaker 1: And one of my favorite things about science is that
27:42
Speaker 1: it's all about people following their passion. Maybe you're really
27:45
Speaker 1: interested in how snails eat other snails, awesome, go study it.
27:49
Speaker 1: You're the right person to do that. And so I
27:52
Speaker 1: think it's good that we got Higgs boson folks doing
27:54
Speaker 1: that and lightning experts doing that, and there's apparently not
27:57
Speaker 1: enough people curious about how lightning works. Yeah. Probably most
28:01
Speaker 1: people think lightning is solved, right, They think, oh, well,
28:03
Speaker 1: we figured that out a long time ago. Um, but
28:06
Speaker 1: we made, you know, a little bit of progress with
28:08
Speaker 1: Ben Franklin, and almost no progress since then until about
28:12
Speaker 1: the seventies. Does that that's the benchmark. Ben Franklin was
28:18
Speaker 1: a pioneer of lightning research, and nobody else has done.
28:22
Speaker 1: It's been like on the last couple of decades that
28:24
Speaker 1: people have really started started to get serious about this
28:26
Speaker 1: and attack this problem. And that's one of the best
28:29
Speaker 1: things about science when people like, all right, let's figure
28:31
Speaker 1: this out. Does this make sense? And and and very
28:35
Speaker 1: quickly you discover there's mysteries everywhere. Right, there's all sorts
28:38
Speaker 1: of weird stuff to explore all around the universe and
28:41
Speaker 1: right here on Earth. Well, that's amazing, um that there
28:44
Speaker 1: are still so many mysteries about it and how it works.
28:47
Speaker 1: All right, let's let's go into now lightning not just
28:50
Speaker 1: here on Earth but in other planets. But first let's
28:54
Speaker 1: take a quick break. All right, we've talked about lightning
29:09
Speaker 1: and what causes is and what we don't know about
29:12
Speaker 1: what causes it. But um, and there are still big
29:15
Speaker 1: mysteries in lightning. That's crazy, it's it's um. It's a
29:18
Speaker 1: big news flash for me. Yeah, and there's all sorts
29:21
Speaker 1: of weird kinds of lightning that people don't understand. And
29:23
Speaker 1: there's sort of two categories there. There's like weird lightning
29:27
Speaker 1: that we've seen, we've verified, but we don't understand like
29:30
Speaker 1: what makes it or what causes it or how it
29:32
Speaker 1: works whatever, sort of like that's serious science. And then
29:36
Speaker 1: there's the sort of crazy lightning stories, right, like things
29:40
Speaker 1: people talk about but no scientists haven't been able to
29:42
Speaker 1: record or verify. And yeah, and one of my first
29:47
Speaker 1: is just like, um, like people see balls of lightning
29:50
Speaker 1: in their house and stuff like that. Yes, exactly. This
29:53
Speaker 1: this continuing series of anecdotal evidence for something called ball lightning,
29:59
Speaker 1: which is suppos is to be like a glowing ball
30:02
Speaker 1: of lightning like ten centimeters wide approximately, that they will
30:06
Speaker 1: like come down people's chimneys and like run around their
30:09
Speaker 1: house and then go out the window. Um, it's bizarre.
30:13
Speaker 1: No scientist has ever seen it, has never been recorded.
30:15
Speaker 1: We only have anecdotal evidence, but we have a lot
30:18
Speaker 1: of anecdotal evidence. It's like in history in the last
30:21
Speaker 1: few hundred years, there's a lot of examples about people
30:24
Speaker 1: writing about this. So if all those people saying, man,
30:26
Speaker 1: I think it's aliens. They might be right, It might
30:31
Speaker 1: be super supernovous are not caused by aliens or its
30:36
Speaker 1: signals from an alien dying star. Yeah. Actually, you know,
30:40
Speaker 1: I don't know that. I don't know the supernova are
30:42
Speaker 1: not caused by aliens, So I really shouldn't say that
30:45
Speaker 1: for certain. It could be um. But you know, ball
30:48
Speaker 1: lightning is like it's just a mystery. Nobody's really captured it. Um.
30:52
Speaker 1: Nobody has been able to explain it. People have done
30:54
Speaker 1: some tests in the lab where they're able to create
30:57
Speaker 1: these weird glowing balls of plasma basically using very special
31:01
Speaker 1: arrangements of moisture and charge whenever. But we don't know
31:04
Speaker 1: if that's really what ball lightning is, and and nobody's
31:08
Speaker 1: been able to create it in a way that like
31:10
Speaker 1: lasts as long as people say it does, you know,
31:12
Speaker 1: all right, And so that that's one weird thinking here
31:15
Speaker 1: in Earth. But you're telling me that there are interesting
31:18
Speaker 1: questions about lightning and other planets. Yeah, exactly. An awesome
31:22
Speaker 1: thing about lightning is that's not unique to Earth. Right.
31:25
Speaker 1: We see weather, of course on other planets, and Saturn
31:28
Speaker 1: and Jupiter in particular, you know, they are these amazing,
31:31
Speaker 1: beautiful planets with obvious cloud patterns, and you can just
31:34
Speaker 1: look at their surface and see there's a lot of
31:36
Speaker 1: stuff going on there, right, And there's swirling clouds and
31:40
Speaker 1: huge storms, and in those storms we see lightning. So
31:43
Speaker 1: there's extra terrestrial lightning. That's a real thing. But one
31:48
Speaker 1: of the mysteries is like does it happen on other planets? Yeah?
31:51
Speaker 1: And is it very similar? Like is it cloud rubbing
31:54
Speaker 1: against each other and then you know, probably costic grays
31:58
Speaker 1: causing it to arc. That's the idea of right. Um,
32:01
Speaker 1: we haven't been able to put probes into those clouds
32:04
Speaker 1: to see if the electric fields are large enough to
32:07
Speaker 1: cause lightning on their own, but it would make sense.
32:10
Speaker 1: I mean, Jupiter is a huge amount of radiation it's producing,
32:13
Speaker 1: and so it would make sense if some of those
32:15
Speaker 1: are also sparked by you know, high energy electrons or
32:18
Speaker 1: protons or something. There's a lively debate also about whether
32:21
Speaker 1: or not there's lightning on Venus, right. Venus has this
32:25
Speaker 1: really thick cloud cover, so we can't see very well
32:28
Speaker 1: into Venus, and people think there should be lightning, and
32:31
Speaker 1: some people claim to have evidence for lightning on Venus,
32:34
Speaker 1: but it's not. Um, not scientifically accepted yet, but we
32:38
Speaker 1: do know what happens on other planets, and I think
32:40
Speaker 1: that's pretty awesome. Like whether on other planets that's for
32:43
Speaker 1: some reason that just tickles the physicist in me. Whether
32:47
Speaker 1: like snow, to feel snow in another planet, that would
32:50
Speaker 1: be cool. Yeah, that would be cool. Um. I also
32:53
Speaker 1: really like here on Earth, when lightning happens, not just
32:56
Speaker 1: in your like standard vanilla thunderstorm, right, It can happen
33:00
Speaker 1: in snow storms. It can happen hurricanes. Yeah, exactly, with
33:04
Speaker 1: snow storms. Yeah, you get like thunder snow or something.
33:08
Speaker 1: What's the name for that? You should be I like that.
33:11
Speaker 1: That sounds like like one of the ThunderCats. Maybe thunder
33:15
Speaker 1: cats snow, I don't know. Yeah, because you know, all
33:21
Speaker 1: that needs to happen is you need to get a
33:23
Speaker 1: charge differential and snow storms, you know, they have these
33:25
Speaker 1: ice crystals and they can run up against each other
33:27
Speaker 1: and you get the right combination of hail and snow
33:29
Speaker 1: together and you get this charge differential, and then you know,
33:32
Speaker 1: Zeus does his thing and sends you a proton from
33:35
Speaker 1: a supernova and boom, you get lightning in a thunderstorm.
33:38
Speaker 1: Can you can get lightning in a snowstorm, it totally happens.
33:42
Speaker 1: And then hurricanes it's also there's something weird about that. No,
33:45
Speaker 1: it's just I mean, a hurricane is just a huge storm.
33:47
Speaker 1: But you know, hurricane is just this awesome wrath of nature.
33:50
Speaker 1: And if you look at it from space, like you know,
33:52
Speaker 1: right now people are suffering suffering from that hurricane in
33:55
Speaker 1: the East Coast, but if you look at it from
33:57
Speaker 1: space you can see lightning flashes all around the hurricane.
34:00
Speaker 1: It just makes it sort of seem like a super
34:02
Speaker 1: hurricane to me. In those cases, it's it's like lightning
34:05
Speaker 1: between clouds, right, Yeah, mostly that's cloud to cloud lightning,
34:09
Speaker 1: and the principle is the same. You know, it's all
34:11
Speaker 1: about this charge differential. Something else that's fascinating about that
34:15
Speaker 1: kind of lightning is you get this big charge differential.
34:17
Speaker 1: The bottom of the cloud is negatively charged, well, the
34:20
Speaker 1: top of the cloud is positively charged. So when the
34:23
Speaker 1: electrons are reaching down to the ground to try to
34:26
Speaker 1: find a path, some other electrons are simultaneously reaching out
34:30
Speaker 1: inside the cloud. So lightning actually starts in both directions,
34:35
Speaker 1: and then if it finds a path to the ground
34:37
Speaker 1: first you get cloud to ground lightning. But if it
34:40
Speaker 1: founds find some connection to the positively charged area of
34:43
Speaker 1: the cloud first, then you get inter cloud lightning inside
34:47
Speaker 1: the cloud. So lightning actually starts in two directions at once. Well,
34:51
Speaker 1: that all just sounds like some kind of Internet business
34:53
Speaker 1: model or something. Cloud to cloud, cloud to ground, that's right. Yeah,
34:58
Speaker 1: that's where the real money is and cloud to cloud business. Yeah,
35:01
Speaker 1: that's really forget physics, Daniel going to plow out the
35:05
Speaker 1: cloud computing. I'm just gonna take one percent of every
35:08
Speaker 1: lightning strike, you know, and then eventually that I add
35:10
Speaker 1: up to a huge amount. All right, So that's um,
35:12
Speaker 1: that's super interesting. I learned a bunch here today about
35:15
Speaker 1: what is lightning and what causes it and all the
35:18
Speaker 1: things we don't know about it. Yeah, and you know,
35:21
Speaker 1: shout out to those scientists who were shooting rockets up
35:24
Speaker 1: into clouds connected to little wires and not getting struck.
35:29
Speaker 1: But they're doing it so that we can understand how
35:31
Speaker 1: lightning works and we can finally maybe put to rest. Um,
35:34
Speaker 1: you know, one of the mysteries, one of the deepest
35:36
Speaker 1: questions people have about amazing natural phenomena right here on Earth.
35:41
Speaker 1: So thank you for listening. We hope you enjoyed that,
35:43
Speaker 1: and we hope that the next time you get to
35:45
Speaker 1: see some lightning, you will look at and get odd
35:49
Speaker 1: not just by the flash of light, but by the
35:51
Speaker 1: mysteries that are inside of that column of me on
35:54
Speaker 1: natural advertisement. And remember the impetus for that lightning strike
35:58
Speaker 1: could have happened a billion years ago in the star
36:00
Speaker 1: far far away, came down to Earth just for you
36:03
Speaker 1: to see it. All right, Thank you for listening, See
36:05
Speaker 1: you next time. If you still have a question after
36:15
Speaker 1: listening to all these explanations, please drop us a line.
36:18
Speaker 1: We'd love to hear from you. You can find us
36:21
Speaker 1: at Facebook, Twitter, and Instagram at Daniel and Jorge That's
36:24
Speaker 1: one word, or email us at Feedback at Daniel and
36:28
Speaker 1: Jorge dot com. Thanks for listening, and remember that Daniel
36:31
Speaker 1: and Jorge Explain the Universe is a production of I
36:34
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