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Speaker 1: Hey, Daniel, what's your feeling about the Moon?

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Speaker 2: I guess I don't have that many strong feelings. Does

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Speaker 2: anyone Do you like it? Do you dislike it? I mean,

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Speaker 2: I guess I'm generally pro moon, although if it's made

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Speaker 2: out of white chocolate, I'm not going to be very

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Speaker 2: happy about it.

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Speaker 1: Oh what if it was would you want to nuke

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Speaker 1: it out of the sky?

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Speaker 2: Oh? Man, that sounds like a disaster. It would cause

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Speaker 2: a shower of molten white chocolate all over the earth.

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Speaker 1: Yeah, a lot of people would be happy.

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Speaker 2: That sounds like a disaster movie.

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Speaker 1: To me, it sounds like you have really charged feelings

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Speaker 1: about the moon and white.

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Speaker 2: Chocolate, both positive and negative.

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Speaker 1: Hi am Jorhemy Cartoonist'm the author of Oliver's Great Big Universe.

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Speaker 2: Hi, I'm Daniel. I'm a particle physicist and a professor

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Speaker 2: at UC Irvine. And you couldn't pay me enough white

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Speaker 2: chocolate to take a trip to the moon.

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Speaker 1: Can we pay you some money to eat white chocolate?

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Speaker 2: I guess it depends on the amount of white chocolate

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Speaker 2: and the amount of money.

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Speaker 1: Wait, you would have wanted to go to the moon?

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Speaker 1: Why not?

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Speaker 2: I mean, I don't take trips to Antarctica, and I'm

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Speaker 2: pretty sure the Moon is like less cozy than Antarctica.

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Speaker 1: It's not about coziness, It's about the adventure, you know,

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Speaker 1: excitement being someplace interesting.

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Speaker 2: Yeah again, still don't take a lot of trips to

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Speaker 2: Antarctica for the same reason.

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Speaker 1: Have you been to Antarctica? How do you know you

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Speaker 1: won't like it.

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Speaker 2: I've never been to Antarctica, but I've been to some

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Speaker 2: places that are sort of Antarctica adjacent, and I wasn't

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Speaker 2: a fan.

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Speaker 1: I've been to the Arctics Circle that was pretty exciting.

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Speaker 1: I've been on a glacier.

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Speaker 2: I know. I'm trying to hook you up with a

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Speaker 2: trip to Antarctica to visit the physics experiments there, but

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Speaker 2: no luck yet.

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Speaker 1: M Are you just trying to get rid of me?

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Speaker 1: Are you hoping that some sort of a freak accident

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Speaker 1: will happen while I'm there.

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Speaker 2: I think that's a conversation you should have with your

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Speaker 2: therapist about your paranoia. I thought you wanted to visit

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Speaker 2: the South Pole. I don't know.

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Speaker 1: There's all very suspicious, Daniel. I mean, of all the

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Speaker 1: places you could send me to Hawaii, Fiji, do you

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Speaker 1: want to send me to the most remote place on Earth.

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Speaker 2: There's also an awesome physics experiment in the south of France.

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Speaker 2: Maybe you want to visit that one.

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Speaker 1: Yeah, let's do it. I'll take it. Is a podcast paying.

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Speaker 2: Everybody chip in crowdsource Jorgees trip to the South of France.

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Speaker 2: We'll see how many contributions we get.

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Speaker 1: There you go, We'll kickstarted. But anyways, welcome to our podcast.

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Speaker 1: Daniel and Jorge Explain the Universe, a production of iHeartRadio.

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Speaker 2: In which we get all charged up about the mysteries

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Speaker 2: of the universe. We are very positive about the idea

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Speaker 2: that humans can understand the nature of the universe that

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Speaker 2: we live in, and not just a few humans operating

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Speaker 2: on the forefront of science. Everybody. We love taking these

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Speaker 2: crazy ideas that scientists have developed and explaining all of

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Speaker 2: them to you.

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Speaker 1: It's right because we are attracted to the deep mysteries

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Speaker 1: of the universe, and we are also repelled by our

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Speaker 1: deep ignorance of the things. We don't know about how

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Speaker 1: things work.

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Speaker 2: But what we definitely do know is that the universe

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Speaker 2: is controlled by forces. There are pushes, there are pulls,

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Speaker 2: there are tugs. Everything that happens out there in the

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Speaker 2: universe is the result of forces in balance and out

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Speaker 2: of balance.

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Speaker 1: Wait, are you sure about that? I mean, I feel

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Speaker 1: like we need for a long time about the force

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Speaker 1: of gravity, but now I hear that there's no just

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Speaker 1: a thing as the gravitational force.

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Speaker 2: You're right, of course, that gravity is not a force.

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Speaker 2: It's just the curvature of space time, which gives the

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Speaker 2: illusion of a force if you're not aware that space

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Speaker 2: is curved in front of you and causing things to

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Speaker 2: move in a way you might not expect. We can

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Speaker 2: still actually describe a lot of that in terms of

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Speaker 2: pseudo forces. So for the spirit of today's conversation about

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Speaker 2: pushes and pulls and what's tugging on the moon and

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Speaker 2: what's not, doesn't really make a difference if gravity is

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Speaker 2: a force or the curvature of space time.

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Speaker 1: I wonder it could it be that we eventually find

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Speaker 1: out that the other forces in nature are also just

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Speaker 1: distortions of space and time or are we pretty sure

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Speaker 1: those are forces forces?

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Speaker 2: No, you're absolutely right, and that is an active idea

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Speaker 2: people are working on. Einstein spent many, many years trying

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Speaker 2: to explain electromagnetism in terms of additional curvature of space time.

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Speaker 2: He thought maybe that force is actually also a pseudo force,

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Speaker 2: just the result of space being curved in additional ways.

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Speaker 2: He never made it work, and one reason is that

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Speaker 2: he didn't understand the weak force, which is crucially related

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Speaker 2: to electromagnetism, So he sort of didn't have the whole picture.

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Speaker 2: But there are people working on that right now. They

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Speaker 2: just haven't succeeded yet.

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Speaker 1: I guess Einstein felt he was kind of forcing it

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Speaker 1: at some point. He didn't want to push it.

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Speaker 2: I think he went around the wrong curve.

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Speaker 1: He felt like he couldn't pull it off.

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Speaker 2: It wasn't a grave enough matter.

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Speaker 1: But it does seem like in our everyday lives, like

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Speaker 1: things are governed by these laws of nature that seem

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Speaker 1: to pull and push on things. And that's kind of

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Speaker 1: what physics it's all about, right, the push and pull

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Speaker 1: of the universe.

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Speaker 2: That's right. And the universe as we see it is

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Speaker 2: shaped by lots of different forces. Stuff in the universe

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Speaker 2: is mostly built out of the more powerful forces, the

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Speaker 2: strong force, electromagnetism. But the overall shape of the universe,

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Speaker 2: the way the Solar System is, the shape of the Earth,

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Speaker 2: the structure of the galaxy and beyond is mostly dominated

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Speaker 2: by the weakest force, gravity.

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Speaker 1: As our gravity is what gives the universe its structure.

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Speaker 1: If it wasn't for gravity, we wouldn't have planets, right,

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Speaker 1: or suns or galaxies, and we wouldn't be here. I mean,

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Speaker 1: be nice to be lighter than what we are, but

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Speaker 1: without gravity, we and none of us would exist.

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Speaker 2: That's right. It's gravity that causes the Sun to burn

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Speaker 2: because it squeezes all that gas together, giving it the

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Speaker 2: high temperature and density needed to ignite fusion. It's gravity

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Speaker 2: that forms the structure of the Earth. It's gravity that's

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Speaker 2: formed the Moon. It's gravity that's formed everything that we

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Speaker 2: see out there in the universe. But that doesn't mean

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Speaker 2: that gravity is the only force at play in our

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Speaker 2: Solar system.

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Speaker 1: Yeah, there are other forces, some of which play an

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Speaker 1: equally important role in our existence. If it wasn't for

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Speaker 1: the electromagnetic force, like, none of our atoms would hold together,

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Speaker 1: and so we also wouldn't be here.

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Speaker 2: That's right. You're basically built out of the electromagnetic force.

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Speaker 2: All of your atoms and molecules are bonded together using

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Speaker 2: electrons and electromagnetism. So basically every structure you're familiar with,

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Speaker 2: is an electromagnetic structure.

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Speaker 1: I feel like we're saying we're basically everything. Everything is

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Speaker 1: everything made out of everything, due to everything.

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Speaker 2: It is an incredible balance of all those forces.

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Speaker 1: Yeah, and sometimes that force pulls and pushes on things

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Speaker 1: in ways that you don't quite expect.

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Speaker 2: And so we think that gravity is the dominant force

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Speaker 2: remaining in the solar system, but that's not always the case.

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Speaker 1: And so on the podcast, we'll be tackling the question

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Speaker 1: what's the electrical charge of the moon? Interesting question, like

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Speaker 1: the moon has as a plug in it?

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Speaker 2: Is the Moon a battery? And if we travel there,

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Speaker 2: can we use it to recharge our phone?

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Speaker 1: There you go, that'd be important. Does it have a

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Speaker 1: USBC connector a USB connector lightning port, the USB Moon

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Speaker 1: connector Yeah, that's what I want to know before you

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Speaker 1: send me to the Moon.

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Speaker 2: You know, the way it is with USB, there's always

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Speaker 2: some new shape you've never seen before.

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Speaker 1: Yeah, Well, hopefully the Moon has a stand under plug.

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Speaker 1: But this is an interesting question to ask about the moon,

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Speaker 1: like the idea that the moon has a charge at all.

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Speaker 2: Yeah, because we're very familiar with the Moon having a mass,

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Speaker 2: which is sort of like a gravitational charge. You you're

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Speaker 2: thinking about gravity as a force and a Newtonian sense,

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Speaker 2: but it's weird to think about the Moon having like

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Speaker 2: an electric charge, like it being overall positive or negative.

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Speaker 1: Hmm. Well, I'm positive we'll get to the bottom of this,

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Speaker 1: but as usual, we were wondering how many people out

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Speaker 1: there had thought about the Moon having a charge or

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Speaker 1: what that charge could be.

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Speaker 2: Thanks very much to everybody who volunteers for this fun

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Speaker 2: segment of the podcast. One of my favorites. I love

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Speaker 2: hearing your voices. Please join the group right to meet

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Speaker 2: at questions at Danielanjorge dot com.

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Speaker 1: So think about it for a second. Do you think

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Speaker 1: the Moon has a charge? Here's what people had to say.

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Speaker 3: I would think planets and moons get their charge from

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Speaker 3: their cores, you know. In Earth's case, I think the

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Speaker 3: iron core gives it a magnetic field. But then again,

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Speaker 3: I guess the charges would cancel out and make it neutral.

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Speaker 2: So I don't know.

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Speaker 3: I don't think the Moon has a core or an

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Speaker 3: electric field as far as I know, so I guess

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Speaker 3: maybe you can call that neutral too.

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Speaker 4: I feel like the Moon should have a total electrical

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Speaker 4: charge of zero. It's probably different locally depending on what's

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Speaker 4: getting hit by the solar wind and being ionized at

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Speaker 4: the dust particular level, but that's probably a zero overall.

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Speaker 5: I'm not sure about the electric charge of the Moon

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Speaker 5: because it doesn't have more to love in it, I think,

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Speaker 5: but since it's spinning, it might have a really small,

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Speaker 5: undetectable amount. But I'm not sure about it.

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Speaker 6: Otherwise, I would have guessed that the electrical charge of

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Speaker 6: the Moon would be zero because I thought that all

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Speaker 6: electrical charge balanced out. But you're asking the question, so

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Speaker 6: I'm guessing it's not zero. I'm not sure though. Maybe

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Speaker 6: it has something to do with the Earth's magnetic field.

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Speaker 6: But I'm really not sure. I'm not too sure what

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Speaker 6: the charge of the Moon would be, but I imagine

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Speaker 6: it has the same charge as the Earth.

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Speaker 1: I believe that the electrical charge of the Moon is zero,

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Speaker 1: just us on Earth. All the positive and negative charges

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Speaker 1: should balance, all right, some charge answers here.

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Speaker 2: Consensus seems to be a zero charge for the Moon.

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Speaker 1: Well, it's not positive or negative. It's just kind of there.

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Speaker 2: The Moon just neutral. Just kind of me.

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Speaker 1: Just kind of mad, as the kids say these days.

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Speaker 1: But the moon is a pretty interesting object out in

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Speaker 1: our night sky. It's big, it's about the quarter of

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Speaker 1: the size and diameter.

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Speaker 2: Of the Earth, right, Yeah, I think that sounds right.

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Speaker 1: Yeah, And it's out there in orbit around the Earth.

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Speaker 1: And so the question is does it have an electrical charge?

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Speaker 1: Why would it have an electrical charge? Or should it

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Speaker 1: have an electrical charge?

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Speaker 2: I think the listeners had the right spirit. That ended

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Speaker 2: up mostly getting the wrong answer because a simple model

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Speaker 2: of the solar system suggests that it shouldn't have any charge,

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Speaker 2: that it should be basically neutral.

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Speaker 1: Well, maybe let's take a step back and talk about

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Speaker 1: the charge of things in general, Like do I have

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Speaker 1: a charge? An overall charge me like my body? Or

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Speaker 1: I guess where does a charge come from? Do I

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Speaker 1: have to add up all my electrons and then add

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Speaker 1: up all my protons and if there's an imbalance, then

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Speaker 1: I have an overall charge? Is that kind of what

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Speaker 1: having a charge means?

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Speaker 2: Yeah, You're made out of charged objects, the quarks, the

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Speaker 2: electrons that are in your body. They all have electric charges,

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Speaker 2: and some of them are positive and some of them

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Speaker 2: are negative, and so you add them all up. It's

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Speaker 2: like a big accounting and if you have more positives

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Speaker 2: the negatives. Then you're positively charged, and you're made up

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Speaker 2: of charged out of the molecules. Sometimes you have ions

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Speaker 2: inside your body which have electrical charges, but the electromagnetic

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Speaker 2: force is very, very powerful, and so it tends to

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Speaker 2: try to neutralize things.

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Speaker 1: But would you say that's an overall way to define

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Speaker 1: my charge or define the charge of something like if

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Speaker 1: it has more electrons than protons, which are made out

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Speaker 1: of quarks, then it has a negative charge.

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Speaker 2: Yeah. That's the definition of the charge of an object

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Speaker 2: is the sum of all the charges of its particles.

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Speaker 1: So if I have excess electrons somehow inside of me,

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Speaker 1: then I'm going to be negative charge, which means that

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Speaker 1: if you put me in front of a whole bunch

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Speaker 1: of electrons, am I going to be repelled by those electrons?

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Speaker 2: Yeah? Exactly. If you're negatively charged and then like a

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Speaker 2: cloud of electrons comes by, you're going to be repelled

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Speaker 2: from those electrons and they will be repelled by you.

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Speaker 2: Or if a cloud of protons comes by, you would

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Speaker 2: be attracted to those protons and they would be attracted

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Speaker 2: to you. And that's sort of the reason why most

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Speaker 2: stuff in the universe is very close to electrically neutral,

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Speaker 2: because electromagnetism is very strong, and if you do have

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Speaker 2: an overall charge, it tends to cancel itself out by

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Speaker 2: slurping up the opposite charge.

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Speaker 1: Right Like, if I have just a whole bunch of

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Speaker 1: electrons floating in space, I guess, first of all, they

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Speaker 1: would repel each other and fly away from each other.

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Speaker 1: But second of all, they would probably attract protons from

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Speaker 1: around them, and then they would quickly become neutral in

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Speaker 1: terms of charge exactly.

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Speaker 2: And that's just what happened in our universe when things

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Speaker 2: cooled down very early on. There were protons and there

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Speaker 2: were electrons, and they were all flying around. The whole

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Speaker 2: universe was charged. It was a plasma, which is just

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Speaker 2: a gas of charged particles. We think overall it was neutral,

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Speaker 2: but like individual electrons and protons of course had charge,

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Speaker 2: but they also had a lot of energy, were moving

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Speaker 2: really really fast, too fast for electromagnetism to sort of

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Speaker 2: capture them. But then when the universe cooled down, eventually

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Speaker 2: they were captured by each other, and protons electrons came

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Speaker 2: together to make neutral hydrogen. Then the whole universe was

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Speaker 2: filled with neutral gas.

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Speaker 1: Oh, that's an interesting question. Is the universe overall charge? Like,

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Speaker 1: is the total number of universal electrons the same as

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Speaker 1: a number of protons?

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Speaker 2: Yeah, great question. We don't know. We think that charge

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Speaker 2: is concerned in the universe, meaning it can't change. So

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Speaker 2: when the universe was born, there was a number which

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Speaker 2: is a total charge and that hasn't ever changed. We

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Speaker 2: think probably that was zero just due to symmetry arguments,

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Speaker 2: but the whole thing is very fuzzy.

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Speaker 1: And poorly now probably zero. Interesting.

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Speaker 2: Yeah, in the same way that we think like matter

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Speaker 2: and antimatter were made at the same rates in the

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Speaker 2: very early universe, although now we have a lot more

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Speaker 2: matter than antimatter, which is not something we understand. We

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Speaker 2: think that positrons and electrons were made at the same

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Speaker 2: rate in the early universe, that we started overall with

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Speaker 2: zero charge and created equal amounts of positive and negative

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Speaker 2: charge particles.

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Speaker 1: All right, So now let's get to the moon. And

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Speaker 1: now the question we're asking today is is the moon

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Speaker 1: positively or negatively charge overall? And you said that the

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Speaker 1: simple model of the moon says that it should be neutral,

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Speaker 1: So why is that?

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Speaker 2: Well, go back to our simple history of the universe.

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Speaker 2: The universe is filled with neutral gas. And what happened

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Speaker 2: after that is gravity took over. Right, Electromagnetism is neutralized out,

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Speaker 2: it's not really pushing and pulling on everything anymore. And

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Speaker 2: now gravity, the weakest force by huge amount, right, like

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Speaker 2: trillions and trillions of times weaker than electromagnetism, finally has

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Speaker 2: a chance to influence things. And it takes millions and

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Speaker 2: billions of years, but it pulls together planets and stars

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Speaker 2: and moons and forms the structure of the universe. The

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Speaker 2: weird thing about gravity is that it can't get canceled out.

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Speaker 2: There's only one charge for gravity. There's positive mass, there's

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Speaker 2: no negative mass, and so gravity forms this structure and

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Speaker 2: it's still the thing that dominates the universe because it's

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Speaker 2: still around. Unlike electromagnetism, it doesn't get neutralized or canceled out.

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Speaker 2: So the simple model of the universe is everything neutralizes

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Speaker 2: and then gravity takes over, and it's basically just the

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Speaker 2: gravity of neutral objects. So the Earth, the Moon, everything

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Speaker 2: should be basically neutral.

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Speaker 1: M I think you're saying that the Moon was basically

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Speaker 1: formed out of rocks, and way before those rocks formed

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Speaker 1: the Moon, those rocks were already electrically neutral.

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Speaker 2: Mmmmm exactly. And if the Moon had like a really

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Speaker 2: big positive charge and the Earth had a really big

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Speaker 2: negative charge, what would happen is that they would slur

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Speaker 2: particles off of each other and neutralize that.

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Speaker 1: Wait wait, wait, do you mean slur particles like pull

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Speaker 1: the electrons out of their rocks?

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Speaker 2: I mean you would hear this giant sucking sound like whew.

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Speaker 2: Quite literally.

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Speaker 1: I thought there was no sound in space. What kind

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Speaker 1: of misinformation are you giving out of here?

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Speaker 2: There is sound on Earth. And if the Moon was

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Speaker 2: sucking electrons off the Earth, we would hear it. Yeah,

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Speaker 2: the Moon was positively charged and the Earth was very

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Speaker 2: negatively charged, then the Moon would suck electrons off the

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Speaker 2: Earth until it was roughly in balance. Because electromagnetism is

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Speaker 2: very powerful.

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Speaker 1: Why would the Moon give up its electrons whatever they're

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Speaker 1: like embedded inside of their atoms.

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Speaker 2: I'm saying, if somehow the Moon was positively charged, like

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Speaker 2: I had a bunch of protons that didn't have electrons

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Speaker 2: to match it. They were hanging out on the Moon,

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Speaker 2: and the Earth had an excess of electrons like hanging

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Speaker 2: out in the atmosphere, then those electrons would get sucked

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Speaker 2: off the Earth to the Moon. The protons might also

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Speaker 2: get sucked off towards the Earth, but electrons are lighter,

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Speaker 2: so they would move further than the protons.

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Speaker 1: But I guess we're sticking to the model where the

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Speaker 1: Moon and the Earth were made out of neutral rocks,

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Speaker 1: and so that's what you're saying. That's a simple model

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Speaker 1: of how things got to be.

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Speaker 2: Yeah, so that simple model tells you that the Moon

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Speaker 2: should either be totally neutral or very close to neutral,

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Speaker 2: because anything else would have gotten balanced out early on,

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Speaker 2: and any large deviation from that later on would be

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Speaker 2: balanced out.

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Speaker 1: All right, Well, that's the first approximation. But as usual,

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Speaker 1: we know that physics and nature likes to surprise this.

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Speaker 1: So let's find out if that's really the case. Is

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Speaker 1: the Moon charged or not? Dig into that, But first

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Speaker 1: let's take a quick break. Right. We're asking the question

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Speaker 1: is the moon charged? Like is it amped up?

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Speaker 2: What else is going on with the moon to give

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Speaker 2: it positive or negative charges?

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Speaker 1: M All right, Well you said that the simple bottle

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Speaker 1: is that the Moon is made out of rocks, and

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Speaker 1: by the time those rocks got made, they were pretty

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Speaker 1: electrically neutral. Because that's kind of how the universe works,

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Speaker 1: and so what makes us think that maybe the universe

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Speaker 1: is not neutral.

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Speaker 2: Well, I think probably the whole universe is neutral. But

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Speaker 2: the Moon, it turns out, is more complex because that

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Speaker 2: simple story we told where you have like just a

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Speaker 2: bunch of gravitational rocks floating in space is not everything

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Speaker 2: that's happening in the Solar system. There's a lot more

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Speaker 2: going on, and specifically, the Sun is pumping out a

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Speaker 2: huge amount of positive and negatively charged particles. The solar wind,

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Speaker 2: which is essentially a stream of plasma flowing through the

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Speaker 2: Solar system, has big impact on everything.

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Speaker 1: You mean, we're all getting kind of showered by sun rays,

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Speaker 1: which not only include light, but also little tiny particles,

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Speaker 1: right like little quarks and electrons.

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Speaker 2: Exactly, mostly protons and electrons. A few positrons are also created,

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Speaker 2: and the Moon is going through this essentially soup of

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Speaker 2: electrons and protons, and that has a big effect on

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Speaker 2: the charge of the Moon.

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Speaker 1: But what isn't the Sun throwing out both positive and

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Speaker 1: negative charges. So basically the solar wind is neutral too,

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Speaker 1: isn't it.

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Speaker 2: The solar wind is overall neutral, But fascinatingly, the backside

387
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Speaker 2: of the moon tends to attract electrons more. Electrons stick

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Speaker 2: to the backside of the Moon more than protons do

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Speaker 2: because electrons are lighter and faster.

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00:18:10,080 --> 00:18:11,840
Speaker 1: Wait wait, wait, wait, go back a little bit. What

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Speaker 1: does that mean. What do you mean electrons are different?

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Speaker 2: Well, electrons and protons have opposite charges, but they don't

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Speaker 2: have the same mass. Protons are much much more massive

394
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Speaker 2: than electrons are, right, and so that affects their velocity.

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Speaker 2: They come out of the Sun with the same energy,

396
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Speaker 2: but they have a lot more mass, so they're moving

397
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Speaker 2: much more slowly and it takes a bigger force to

398
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Speaker 2: accelerate them. And so electrons come out of the Sun

399
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Speaker 2: moving faster, and so there's just like a greater flux

400
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Speaker 2: of them hitting the Moon than the.

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Speaker 1: Protons, a greater flux.

402
00:18:40,960 --> 00:18:44,160
Speaker 2: So there's like more electrons per second per square meter

403
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Speaker 2: hitting the Moon than there are protons.

404
00:18:47,160 --> 00:18:49,199
Speaker 1: So wouldn't that mean that the Sun is making more

405
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Speaker 1: electrons than protons.

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Speaker 2: It's making the same number. But because the electrons are faster,

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Speaker 2: more of than are getting out to the moon. Like,

408
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Speaker 2: the protons don't have as much energy, so they don't

409
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Speaker 2: always get out to the moon, and they certainly don't

410
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Speaker 2: get out as rapidly.

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00:19:01,119 --> 00:19:03,040
Speaker 1: Wait wait, wait, so you're saying that, what do you mean,

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Speaker 1: like some of the protons don't make it out to

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Speaker 1: the moon, like they get stuck somewhere.

414
00:19:06,640 --> 00:19:08,879
Speaker 2: Some of them get stuck. They just like exist in

415
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Speaker 2: the outer layers of the Sun.

416
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Speaker 1: Like the Sun is punet electrons and protons. But some

417
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Speaker 1: of the protons that don't get very far they maybe

418
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Speaker 1: get stuck back into the Sun you're saying, or they

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Speaker 1: get it's trapped into orbit with the Sun.

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Speaker 2: Yeah, exactly. And there are electrons and protons that do

421
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Speaker 2: make it out there by the Moon. But again the

422
00:19:25,560 --> 00:19:28,359
Speaker 2: electrons are moving faster and so they just tend to

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Speaker 2: hit the Moon more.

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00:19:29,520 --> 00:19:31,000
Speaker 1: But then what would that mean that the center of

425
00:19:31,040 --> 00:19:34,320
Speaker 1: the solar system it has a positive charge, if you know,

426
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Speaker 1: if there's more electrons leaving it than protons, that.

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00:19:37,359 --> 00:19:40,600
Speaker 2: Does tend to make the Sun more positive than negative.

428
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Speaker 2: There's a lot of other processes happening at the same

429
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Speaker 2: time that affect the overall charge. For example, the streams

430
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Speaker 2: of electrons end up creating a positive charge at the

431
00:19:50,119 --> 00:19:53,240
Speaker 2: core of the solar system, but that in turn makes

432
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Speaker 2: an electric field that tends to accelerate positive charges away

433
00:19:57,440 --> 00:20:00,000
Speaker 2: from the Sun, which ends up helping to balance that out.

434
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Speaker 2: So you see how electromagnetic effects tend to neutralize themselves.

435
00:20:04,840 --> 00:20:07,399
Speaker 2: The key takeaway is not that the Sun is throwing

436
00:20:07,400 --> 00:20:10,560
Speaker 2: out electrons which are hitting the Moon, but just more generally,

437
00:20:10,560 --> 00:20:13,639
Speaker 2: that the Sun fills the solar system with charged particles

438
00:20:13,960 --> 00:20:17,040
Speaker 2: which are then around to interact with the Moon. So

439
00:20:17,080 --> 00:20:19,560
Speaker 2: that's a whole other topic we can dig into, like

440
00:20:19,600 --> 00:20:22,239
Speaker 2: what is the electrical charge of the Sun. Turns out

441
00:20:22,280 --> 00:20:24,640
Speaker 2: to be much more complicated even than the electrical charge

442
00:20:24,640 --> 00:20:25,080
Speaker 2: of the moon.

443
00:20:25,600 --> 00:20:29,479
Speaker 1: Hmmm. But I guess it does have a positive charge

444
00:20:29,520 --> 00:20:32,080
Speaker 1: because you know, the Sun is so sunny all the time.

445
00:20:33,520 --> 00:20:35,440
Speaker 2: I've never seen the Sun be negative. That's true.

446
00:20:36,320 --> 00:20:38,399
Speaker 1: There you go, all right. So then the idea is

447
00:20:38,440 --> 00:20:41,600
Speaker 1: that the Sun is positive and negative charges in the

448
00:20:41,640 --> 00:20:44,920
Speaker 1: solar wind, but more electrons make it out to where

449
00:20:44,960 --> 00:20:47,960
Speaker 1: we are, and so are basically weed the Earth and

450
00:20:48,040 --> 00:20:51,400
Speaker 1: the Moon are getting showered by more electrons than protons.

451
00:20:51,560 --> 00:20:51,920
Speaker 3: Mm hmm.

452
00:20:52,640 --> 00:20:54,880
Speaker 2: But this turns out to be a dominant effect only

453
00:20:54,920 --> 00:20:58,000
Speaker 2: on the back side of the Moon. The backside of

454
00:20:58,000 --> 00:21:00,240
Speaker 2: the Moon, you have this like sheath of plasma, these

455
00:21:00,240 --> 00:21:03,359
Speaker 2: protons and these electrons that have come along from the

456
00:21:03,400 --> 00:21:05,879
Speaker 2: solar wind and they're hanging out there and more the

457
00:21:05,960 --> 00:21:08,479
Speaker 2: electrons end up on the Moon than the protons. So

458
00:21:08,520 --> 00:21:11,560
Speaker 2: the backside of the Moon is negative. But there's a

459
00:21:11,680 --> 00:21:14,480
Speaker 2: very different process that dominates on the other side of

460
00:21:14,480 --> 00:21:16,480
Speaker 2: the Moon, on the sun facing side of the moon.

461
00:21:16,560 --> 00:21:18,679
Speaker 1: Wait wait, wait, so okay, so I'm the Moon and

462
00:21:18,720 --> 00:21:21,360
Speaker 1: I'm facing the Sun and I'm getting showered by electrons

463
00:21:21,480 --> 00:21:25,120
Speaker 1: and a little bit of protons. Now what you're saying

464
00:21:25,160 --> 00:21:28,080
Speaker 1: that the electrons stick to my backside, why would that be?

465
00:21:28,280 --> 00:21:30,439
Speaker 2: The electrons will also stick to your front side. But

466
00:21:30,480 --> 00:21:34,359
Speaker 2: there's another process on your front side that's even more powerful.

467
00:21:34,520 --> 00:21:38,159
Speaker 2: That's forcing the front side to become positively charged, and

468
00:21:38,200 --> 00:21:41,800
Speaker 2: that's the photoelectric effect. Photons from the Sun, really high

469
00:21:41,920 --> 00:21:45,679
Speaker 2: energy particles hit the Moon and they eject electrons. This

470
00:21:45,800 --> 00:21:48,399
Speaker 2: is the same experiment that Einstein wather bo fries for

471
00:21:48,480 --> 00:21:51,080
Speaker 2: explaining if you shine light on a piece of metal,

472
00:21:51,320 --> 00:21:54,840
Speaker 2: you'll give energy to electrons and eject electrons from the metal,

473
00:21:55,200 --> 00:21:58,679
Speaker 2: making it overall positively charged. The same thing happens on

474
00:21:58,720 --> 00:22:01,240
Speaker 2: the sun facing side of the mo Moon, making that

475
00:22:01,480 --> 00:22:04,560
Speaker 2: side positive and the backside ends up negative.

476
00:22:04,640 --> 00:22:06,840
Speaker 1: Okay, So I'm the Moon and I'm getting hit by

477
00:22:07,000 --> 00:22:09,560
Speaker 1: sun rays. So forget the electrons for now, I'm just

478
00:22:09,560 --> 00:22:12,680
Speaker 1: getting hit by sunlight, which are photons. And you're saying

479
00:22:12,680 --> 00:22:15,760
Speaker 1: it's kicking off the electrons off of the rocks facing

480
00:22:15,760 --> 00:22:18,720
Speaker 1: the sun. But where are those electrons going? Are you

481
00:22:18,760 --> 00:22:20,320
Speaker 1: saying they're flying off into space?

482
00:22:20,440 --> 00:22:23,200
Speaker 2: They're flying off into space exactly. The Moon doesn't have

483
00:22:23,240 --> 00:22:26,280
Speaker 2: a significant atmosphere as what they call an exosphere we

484
00:22:26,359 --> 00:22:28,919
Speaker 2: talked about once on the podcast, so they don't like

485
00:22:29,040 --> 00:22:32,600
Speaker 2: run into other particles. It's basically collisionless, so they just

486
00:22:32,640 --> 00:22:33,600
Speaker 2: fly out into space.

487
00:22:33,680 --> 00:22:36,320
Speaker 1: Yeah, okay, Well what's kicking them off into space?

488
00:22:36,440 --> 00:22:39,119
Speaker 2: The photons, right, Photons are coming in hitting those rocks,

489
00:22:39,160 --> 00:22:41,639
Speaker 2: giving those electrons a boost so they have enough energy

490
00:22:41,640 --> 00:22:44,320
Speaker 2: to leave the rocks and also leave the Moon.

491
00:22:44,840 --> 00:22:47,480
Speaker 1: Okay. So you're saying, like the moon's getting a little

492
00:22:47,480 --> 00:22:51,320
Speaker 1: bit of a sunburn, and the sunburn basically makes the

493
00:22:51,359 --> 00:22:54,800
Speaker 1: surface of the Moon facing the sun positively charge. Okay,

494
00:22:54,840 --> 00:23:00,879
Speaker 1: so now my sun facing side is positively charge. And

495
00:23:00,920 --> 00:23:03,280
Speaker 1: you're saying, now I'm getting a shower of electrons from

496
00:23:03,359 --> 00:23:03,760
Speaker 1: the Sun.

497
00:23:03,880 --> 00:23:05,800
Speaker 2: That's right. At the same time, you have a shower

498
00:23:05,800 --> 00:23:08,560
Speaker 2: of electrons from the sun, and your backside tends to

499
00:23:08,600 --> 00:23:12,280
Speaker 2: attract those electrons. Those electrons end up in this plasma

500
00:23:12,359 --> 00:23:14,920
Speaker 2: sheath that's around you. Plasma member is just a mix

501
00:23:15,119 --> 00:23:16,560
Speaker 2: of protons and electrons.

502
00:23:16,600 --> 00:23:18,600
Speaker 1: So it would in the front facing side, which is

503
00:23:18,720 --> 00:23:22,120
Speaker 1: positively charged, wouldn't that attract the electrons hitting me and

504
00:23:22,160 --> 00:23:23,600
Speaker 1: make them stick to me more?

505
00:23:23,720 --> 00:23:26,080
Speaker 2: It does do that, Yeah, and that limits the overall

506
00:23:26,119 --> 00:23:29,680
Speaker 2: positive charge of the front side. Right. The more positively

507
00:23:29,720 --> 00:23:32,480
Speaker 2: charged she gets, the more it pulls electrons back out

508
00:23:32,520 --> 00:23:34,720
Speaker 2: of the solar wind and out of this plasma. So

509
00:23:34,800 --> 00:23:37,520
Speaker 2: this isn't a huge effect. It's self limiting. As we

510
00:23:37,560 --> 00:23:41,240
Speaker 2: talked about, electromagnetism can be neutralized, and anytime you build

511
00:23:41,280 --> 00:23:43,920
Speaker 2: up a big charge, it tends to limit itself. But

512
00:23:44,000 --> 00:23:46,720
Speaker 2: there's a constant process here. You're constant getting bombarded by

513
00:23:46,720 --> 00:23:49,600
Speaker 2: more and more photons where it's generating more of a

514
00:23:49,640 --> 00:23:52,000
Speaker 2: positive charge, so it sort of comes into balance.

515
00:23:52,000 --> 00:23:55,800
Speaker 1: Oh, I see, so getting electrons knocked up into space

516
00:23:55,840 --> 00:23:58,959
Speaker 1: by the sunlight, but I'm also getting showered by electrons

517
00:23:59,000 --> 00:24:01,679
Speaker 1: from the sun. But maybe those two are not the

518
00:24:01,760 --> 00:24:05,680
Speaker 1: same amounts, and so overall I have a little you're

519
00:24:05,720 --> 00:24:07,600
Speaker 1: saying overall, I'm still left with a little bit of

520
00:24:07,600 --> 00:24:09,840
Speaker 1: a positive charge in my sun facing side.

521
00:24:09,920 --> 00:24:12,879
Speaker 2: Yes, exactly, your sunburn side is positively charged.

522
00:24:12,920 --> 00:24:14,760
Speaker 1: Okay, so then what happens.

523
00:24:14,520 --> 00:24:17,160
Speaker 2: And on the backside, as we talked about, you're negatively charged. Wait,

524
00:24:17,160 --> 00:24:19,119
Speaker 2: why so the front side gets charged because it's being

525
00:24:19,160 --> 00:24:22,200
Speaker 2: hit by these photons, right, that doesn't happen on the backside.

526
00:24:22,720 --> 00:24:25,000
Speaker 2: The backside of the Moon is dark. Photons don't make

527
00:24:25,040 --> 00:24:28,080
Speaker 2: it there, right, and so there's no photons to drive

528
00:24:28,119 --> 00:24:31,480
Speaker 2: it positively charged. All you have are the protons and

529
00:24:31,520 --> 00:24:35,120
Speaker 2: the electrons floating around in this plasma. And the electrons

530
00:24:35,160 --> 00:24:37,760
Speaker 2: are much higher velocity and they tend to hit the

531
00:24:37,800 --> 00:24:39,280
Speaker 2: Moon's surface and stick more.

532
00:24:39,440 --> 00:24:42,520
Speaker 1: Wait, I thought that this is not facing the Sun,

533
00:24:43,359 --> 00:24:45,040
Speaker 1: and most of this stuff is coming from the Sun

534
00:24:45,680 --> 00:24:47,679
Speaker 1: to where is my backside of the moon catching all

535
00:24:47,680 --> 00:24:48,119
Speaker 1: this stuff?

536
00:24:48,160 --> 00:24:50,720
Speaker 2: There's a gravitational effect here, right, You have this like

537
00:24:50,800 --> 00:24:54,000
Speaker 2: solar wind that's washing over the Moon, and then some

538
00:24:54,040 --> 00:24:56,800
Speaker 2: of the protons and the electrons get pulled around on

539
00:24:56,840 --> 00:24:59,680
Speaker 2: the backside, and you have this plasma of electrons and

540
00:24:59,720 --> 00:25:03,639
Speaker 2: proto hanging out on the backside because of gravity. And

541
00:25:03,680 --> 00:25:06,120
Speaker 2: then the electrons get pulled down to the Moon more

542
00:25:06,160 --> 00:25:10,000
Speaker 2: than the protons because electrons are faster moving and lighter.

543
00:25:10,119 --> 00:25:14,640
Speaker 1: So you're saying the backside of my moon sucks electrons

544
00:25:14,680 --> 00:25:15,640
Speaker 1: in through gravity.

545
00:25:15,760 --> 00:25:18,000
Speaker 2: Yeah, And also the electrons are moving faster and they

546
00:25:18,080 --> 00:25:20,000
Speaker 2: end up hitting the backside of the moon.

547
00:25:20,119 --> 00:25:24,560
Speaker 1: M all right. So then and more electrical than positive

548
00:25:24,560 --> 00:25:26,600
Speaker 1: because that's just what the solar wind is made out

549
00:25:26,600 --> 00:25:26,680
Speaker 1: of it.

550
00:25:26,760 --> 00:25:29,320
Speaker 2: And because electrons are lighter, right, they are easier to

551
00:25:29,359 --> 00:25:32,560
Speaker 2: pull down, And so you end up with this positive

552
00:25:32,640 --> 00:25:35,359
Speaker 2: charge on one side and this negative charge on the

553
00:25:35,400 --> 00:25:39,080
Speaker 2: other side. And then there's this threshold, this terminator region

554
00:25:39,560 --> 00:25:42,600
Speaker 2: right at the edge of darkness and light where it's

555
00:25:42,640 --> 00:25:46,040
Speaker 2: totally neutral between the positive and the negative. So this

556
00:25:46,200 --> 00:25:49,280
Speaker 2: is like a ring of neutrality on the Moon between

557
00:25:49,320 --> 00:25:52,400
Speaker 2: the positive these charged sun facing side and the negatively

558
00:25:52,520 --> 00:25:53,600
Speaker 2: charged dark side.

559
00:25:53,680 --> 00:25:57,520
Speaker 1: Hmmm, that's super interesting. But I wonder, like, isn't the

560
00:25:57,520 --> 00:25:59,680
Speaker 1: Moon rotating with respect to the Sun, so r and

561
00:25:59,760 --> 00:26:04,720
Speaker 1: d these surfaces and positive negative surfaces rotating all the

562
00:26:04,720 --> 00:26:05,520
Speaker 1: time and changing.

563
00:26:05,720 --> 00:26:09,000
Speaker 2: Yes. Absolutely. As the moon rotates, a different part of

564
00:26:09,040 --> 00:26:11,919
Speaker 2: it comes into contact with the photons, and so a

565
00:26:11,960 --> 00:26:15,240
Speaker 2: different part of the moon becomes positive and negatively charged.

566
00:26:15,560 --> 00:26:19,239
Speaker 2: This charging and discharging times are very very quick, and

567
00:26:19,320 --> 00:26:21,960
Speaker 2: so like fractions of a second, so there's not like

568
00:26:22,000 --> 00:26:24,680
Speaker 2: a lag between the charge of the moon and which

569
00:26:24,720 --> 00:26:25,800
Speaker 2: part the Sun is hitting.

570
00:26:26,520 --> 00:26:28,159
Speaker 1: So when I look at the moon, whether it's like

571
00:26:28,200 --> 00:26:31,480
Speaker 1: full moon or half moon, basically when I see it,

572
00:26:31,480 --> 00:26:33,760
Speaker 1: I should imagine that the part that we can see,

573
00:26:33,800 --> 00:26:36,800
Speaker 1: the light side, is positively charged and the dark side

574
00:26:36,840 --> 00:26:39,040
Speaker 1: is negatively charge no matter what phase of the moon

575
00:26:39,080 --> 00:26:39,399
Speaker 1: it is in.

576
00:26:39,960 --> 00:26:41,719
Speaker 2: Exactly, if you can see half of the moon and

577
00:26:41,720 --> 00:26:44,320
Speaker 2: half of it is lit, then that side is positive

578
00:26:44,320 --> 00:26:47,480
Speaker 2: and the dark half is negative. Then as it rotates,

579
00:26:47,680 --> 00:26:50,440
Speaker 2: those charges change. So if you're just standing on the

580
00:26:50,480 --> 00:26:52,840
Speaker 2: surface of the moon, the surface you're standing on goes

581
00:26:52,840 --> 00:26:57,000
Speaker 2: from being positively to negatively charged from daytime to nighttime.

582
00:26:57,160 --> 00:26:59,920
Speaker 1: Hmmm, that sounds super interesting. See what do you want

583
00:27:00,119 --> 00:27:05,840
Speaker 1: experience that yourself? I mean, you talk so excitedly about it.

584
00:27:06,200 --> 00:27:07,440
Speaker 1: Wouldn't it be great to be there?

585
00:27:08,880 --> 00:27:10,760
Speaker 2: I think it's super fascinating, But I think it could

586
00:27:10,760 --> 00:27:13,600
Speaker 2: also be unpleasant. I mean we're talking about like up

587
00:27:13,640 --> 00:27:16,720
Speaker 2: to forty five hundred volts of static electricity.

588
00:27:16,760 --> 00:27:19,280
Speaker 1: Wait what, yeah? That much?

589
00:27:19,760 --> 00:27:22,720
Speaker 2: Yes, it's so powerful that it causes like dust to

590
00:27:22,960 --> 00:27:26,200
Speaker 2: levitate on the surface of the Moon. If your dust

591
00:27:26,280 --> 00:27:29,200
Speaker 2: develops a charge, it can repel the surface of the moon.

592
00:27:29,560 --> 00:27:33,000
Speaker 2: You have like electromagnetic levitation happening on the surface of

593
00:27:33,000 --> 00:27:33,359
Speaker 2: the moon.

594
00:27:33,680 --> 00:27:37,480
Speaker 1: That just makes it sound more exciting, Daniel, I.

595
00:27:37,520 --> 00:27:39,680
Speaker 2: Think it's exciting for other people to go and take

596
00:27:39,720 --> 00:27:41,960
Speaker 2: pictures and tell me all about it while I stay

597
00:27:41,960 --> 00:27:44,480
Speaker 2: in the comfort of southern California.

598
00:27:44,800 --> 00:27:47,000
Speaker 1: I see charge neutral on your couch.

599
00:27:47,880 --> 00:27:50,719
Speaker 2: The astronaut saw this. You can see dust levitating like

600
00:27:50,760 --> 00:27:53,760
Speaker 2: a meter off of the Moon's surface if you go

601
00:27:53,800 --> 00:27:54,080
Speaker 2: for a.

602
00:27:54,000 --> 00:27:56,399
Speaker 1: Walk, meaning that there is like if you're in the

603
00:27:56,480 --> 00:27:58,960
Speaker 1: light side, there's just a lot of it's just a

604
00:27:58,960 --> 00:28:02,640
Speaker 1: lot of electrons floating and things. Everything's negative charge, which

605
00:28:02,680 --> 00:28:05,400
Speaker 1: makes the dust repel the rest of the dust which

606
00:28:05,400 --> 00:28:05,960
Speaker 1: makes it float.

607
00:28:06,000 --> 00:28:08,000
Speaker 2: Yeah, it can repel the surface. So if you're standing

608
00:28:08,000 --> 00:28:10,199
Speaker 2: on the surface of the moon and it's daytime, so

609
00:28:10,240 --> 00:28:13,040
Speaker 2: you're in the lift part, the surface is positively charged.

610
00:28:13,400 --> 00:28:16,240
Speaker 2: So if you can have a rock be also positively charged,

611
00:28:16,280 --> 00:28:18,600
Speaker 2: then it will repel the surface of the moon. You

612
00:28:18,680 --> 00:28:20,320
Speaker 2: just got to like rub the rock and brust some

613
00:28:20,359 --> 00:28:23,240
Speaker 2: electrons off of it, just that hard. You can do

614
00:28:23,280 --> 00:28:25,680
Speaker 2: that with like a rag then it will be positive

615
00:28:25,720 --> 00:28:28,840
Speaker 2: and it can float. It's not something we experienced like

616
00:28:28,880 --> 00:28:30,800
Speaker 2: down here on Earth very often, like unless you're in

617
00:28:30,800 --> 00:28:32,400
Speaker 2: a magnetically levitating train.

618
00:28:32,520 --> 00:28:34,840
Speaker 1: M And I guess the same would happen in the

619
00:28:34,920 --> 00:28:36,880
Speaker 1: dark side too, right, I mean, the same effect would

620
00:28:36,880 --> 00:28:39,600
Speaker 1: happen in the dark side, like you might see dust floating,

621
00:28:39,600 --> 00:28:40,680
Speaker 1: but for the opposite reason.

622
00:28:40,800 --> 00:28:42,960
Speaker 2: Yeah, exactly. And so if you plan to like have

623
00:28:43,040 --> 00:28:45,520
Speaker 2: your house plants levitate, then you have to switch from

624
00:28:45,560 --> 00:28:48,600
Speaker 2: positive to negative charge as the day goes into night.

625
00:28:48,800 --> 00:28:51,360
Speaker 1: Mmm. Right, like a dawn and a dust things would

626
00:28:51,360 --> 00:28:52,080
Speaker 1: fall to the ground.

627
00:28:53,520 --> 00:28:55,520
Speaker 2: Sounds like a good problem for the engineers.

628
00:28:55,160 --> 00:28:58,840
Speaker 1: Yeah exactly, or just you know, a handy man with

629
00:28:58,840 --> 00:29:02,600
Speaker 1: a hammer and a nail. All right, Well, it sounds

630
00:29:02,680 --> 00:29:07,160
Speaker 1: like the moon has at all times a positively charged

631
00:29:07,200 --> 00:29:10,600
Speaker 1: side and a negatively charged side at all times. But

632
00:29:11,040 --> 00:29:14,080
Speaker 1: maybe the question is does it overall have a positive

633
00:29:14,160 --> 00:29:17,600
Speaker 1: or negative charge? So let's dig into that. But first

634
00:29:17,960 --> 00:29:33,280
Speaker 1: let's take another quick break. All right, we're asking charge

635
00:29:33,360 --> 00:29:35,520
Speaker 1: questions about the moon. Does the moon have a charge?

636
00:29:35,920 --> 00:29:38,040
Speaker 1: And it sort of does? I guess it depends on

637
00:29:38,080 --> 00:29:39,960
Speaker 1: which side of the moon you're in. If you're in

638
00:29:39,960 --> 00:29:42,600
Speaker 1: the light side being hit by sunlight, then things are

639
00:29:42,640 --> 00:29:45,080
Speaker 1: positively charged where you are, and if you're in the

640
00:29:45,120 --> 00:29:47,720
Speaker 1: dark side, things are negatively charged by a lot. You

641
00:29:47,760 --> 00:29:50,160
Speaker 1: said about forty five hundred volts.

642
00:29:50,200 --> 00:29:52,360
Speaker 2: It can be up to that. Yeah, that's the largest

643
00:29:52,400 --> 00:29:53,120
Speaker 2: that they've measured.

644
00:29:53,280 --> 00:29:56,000
Speaker 1: Wow, So why doesn't it just act like a giant battery?

645
00:29:56,040 --> 00:29:58,800
Speaker 1: And you see these you know, sparks or currents going

646
00:29:58,840 --> 00:29:59,360
Speaker 1: through the moon.

647
00:29:59,480 --> 00:30:01,640
Speaker 2: You don't get lightning storms on the moon, right, There

648
00:30:01,680 --> 00:30:04,320
Speaker 2: isn't like another layer there to discharge from. And I

649
00:30:04,360 --> 00:30:06,880
Speaker 2: think it depends also on the distance over which you

650
00:30:06,960 --> 00:30:10,200
Speaker 2: have this voltage, but it can potentially be dangerous for

651
00:30:10,240 --> 00:30:12,320
Speaker 2: stuff on the moon if you have like electrical equipment

652
00:30:12,360 --> 00:30:13,440
Speaker 2: up there. That's very sensitive.

653
00:30:13,680 --> 00:30:15,760
Speaker 1: M But I guess if the light side and the

654
00:30:15,840 --> 00:30:19,640
Speaker 1: darks are so differently charged, why doesn't the charge equalize,

655
00:30:19,640 --> 00:30:22,200
Speaker 1: Like why don't you get a whole bunch of electrons

656
00:30:22,200 --> 00:30:24,600
Speaker 1: from the backside rushing to the front side.

657
00:30:24,640 --> 00:30:26,920
Speaker 2: Some of that does happen, right, This is self limiting,

658
00:30:26,960 --> 00:30:28,719
Speaker 2: and so this is like the result of a balance

659
00:30:28,760 --> 00:30:31,200
Speaker 2: of all these processes. If you turned off the solar wind,

660
00:30:31,200 --> 00:30:34,120
Speaker 2: for example, then eventually the moon would just neutralize. But

661
00:30:34,200 --> 00:30:37,760
Speaker 2: the solar wind is constantly making this happen, and really interestingly,

662
00:30:37,880 --> 00:30:39,800
Speaker 2: when the solar wind is stronger, like when you have

663
00:30:39,840 --> 00:30:43,240
Speaker 2: solar storms, these effects grow more dramatic. Then the moon

664
00:30:43,320 --> 00:30:46,640
Speaker 2: is more charged, or when the moon passes through like

665
00:30:46,680 --> 00:30:49,560
Speaker 2: the magnetic tail of the Earth, which tends to focus

666
00:30:49,560 --> 00:30:52,959
Speaker 2: the solar wind, then it also gets more powerful. So

667
00:30:53,040 --> 00:30:54,680
Speaker 2: it sort of depends on the solar weather.

668
00:30:54,880 --> 00:30:55,200
Speaker 5: Mmm.

669
00:30:55,880 --> 00:30:58,800
Speaker 1: Interesting, Okay, so then the light side is positively charged

670
00:30:58,800 --> 00:31:01,040
Speaker 1: and dark side is maked charged. But does it have

671
00:31:01,480 --> 00:31:04,000
Speaker 1: a charge overall or does it all balance out to

672
00:31:04,120 --> 00:31:05,320
Speaker 1: zero for the whole mood?

673
00:31:05,360 --> 00:31:07,800
Speaker 2: So this is really interesting question, like philosophically, like do

674
00:31:07,800 --> 00:31:10,960
Speaker 2: you really mean exactly zero? Because I think that's pretty

675
00:31:11,040 --> 00:31:13,480
Speaker 2: unlikely for the number of protons and the number of

676
00:31:13,520 --> 00:31:16,760
Speaker 2: electrons to be exactly matched to each other. It's like

677
00:31:16,880 --> 00:31:20,520
Speaker 2: flipping a billion coins and getting fifty percent heads exactly.

678
00:31:20,760 --> 00:31:23,160
Speaker 2: I think it's unlikely. So I'm sure the moon has

679
00:31:23,200 --> 00:31:26,200
Speaker 2: some overall charge, but I bet it's very very close

680
00:31:26,240 --> 00:31:28,800
Speaker 2: to zero because it's mostly made of neutral stuff, and

681
00:31:28,840 --> 00:31:31,760
Speaker 2: then the surfaces are a little bit charged, but one's positive,

682
00:31:31,800 --> 00:31:34,000
Speaker 2: one's negative, So I think overall it's going to be

683
00:31:34,120 --> 00:31:35,040
Speaker 2: very close to zero.

684
00:31:35,800 --> 00:31:39,320
Speaker 1: But here, you're just speculating, or yes.

685
00:31:40,640 --> 00:31:42,920
Speaker 2: I'd be pretty confident that if you added up every

686
00:31:42,920 --> 00:31:45,280
Speaker 2: single particle on the Moon, it would not come out

687
00:31:45,360 --> 00:31:46,960
Speaker 2: to a perfect balance of zero.

688
00:31:47,240 --> 00:31:50,040
Speaker 1: Right, But I guess would it be negative or positive?

689
00:31:50,680 --> 00:31:51,560
Speaker 1: What do you think it would be?

690
00:31:51,600 --> 00:31:53,800
Speaker 2: If I had to guess, I'd probably lean negative because

691
00:31:53,800 --> 00:31:55,720
Speaker 2: I think the effects of the sun light probably taper

692
00:31:55,760 --> 00:31:59,000
Speaker 2: off more quickly near the terminator region as the sun

693
00:31:59,080 --> 00:32:02,440
Speaker 2: sort of gets low in the Moon's sky, So overall

694
00:32:02,480 --> 00:32:04,760
Speaker 2: that might be a little bit weaker than the effects

695
00:32:04,760 --> 00:32:06,840
Speaker 2: on the negative side. But I'm really not sure.

696
00:32:07,400 --> 00:32:07,640
Speaker 5: Hmm.

697
00:32:08,240 --> 00:32:12,040
Speaker 1: I see, like, if the sunlight effect kicking off electrons

698
00:32:12,080 --> 00:32:14,920
Speaker 1: off of the rocks is not as strong as like

699
00:32:15,000 --> 00:32:17,960
Speaker 1: the idea of being showered by a whole bunch of

700
00:32:17,960 --> 00:32:19,880
Speaker 1: electrons from the sun, then overall it would have a

701
00:32:19,920 --> 00:32:23,160
Speaker 1: negative charge. Yeah, exactly, But it's not quite clear, right, Like,

702
00:32:23,240 --> 00:32:26,000
Speaker 1: maybe maybe the sunlight does kick off more electrons than

703
00:32:26,240 --> 00:32:27,680
Speaker 1: get absorbed from the silver wind.

704
00:32:27,760 --> 00:32:30,560
Speaker 2: Mm, And this is not something we know the answer to.

705
00:32:30,640 --> 00:32:33,040
Speaker 2: There are folks who study the charge of the Moon,

706
00:32:33,560 --> 00:32:36,000
Speaker 2: and they make some measurements from things orbiting the Moon,

707
00:32:36,080 --> 00:32:39,000
Speaker 2: but mostly they have models that describe like these plasmachines

708
00:32:39,040 --> 00:32:41,920
Speaker 2: and on these processes we talked about the photo electric effect,

709
00:32:42,240 --> 00:32:44,080
Speaker 2: and they try to match them up with a few

710
00:32:44,120 --> 00:32:46,400
Speaker 2: measurements they make. But we don't have a whole lot

711
00:32:46,440 --> 00:32:49,360
Speaker 2: of measurements on the surface of the Moon, and we

712
00:32:49,440 --> 00:32:52,600
Speaker 2: have some measurements from Apollo astronauts. We're not sure that

713
00:32:52,640 --> 00:32:55,920
Speaker 2: they were always working in like typical conditions, and as

714
00:32:55,960 --> 00:32:59,200
Speaker 2: we know, this is like constantly changing throughout the day.

715
00:33:00,120 --> 00:33:02,480
Speaker 1: Throughout the seasons as well, right like as it interacts

716
00:33:02,480 --> 00:33:03,000
Speaker 1: with the Earth.

717
00:33:03,120 --> 00:33:06,040
Speaker 2: Maybe also yeah, and it's probably not a coincidence, but

718
00:33:06,120 --> 00:33:08,800
Speaker 2: most of the Apollo astronauts tend to visit the Moon

719
00:33:08,920 --> 00:33:12,360
Speaker 2: under pretty normal solar conditions, Like if there's going to

720
00:33:12,360 --> 00:33:14,200
Speaker 2: be a big solar storm, then you're probably not going

721
00:33:14,280 --> 00:33:16,880
Speaker 2: to launch your astronauts up to the Moon. And so

722
00:33:16,920 --> 00:33:19,960
Speaker 2: we tend to have measurements during intervals of less extreme

723
00:33:20,120 --> 00:33:20,800
Speaker 2: space weather.

724
00:33:22,280 --> 00:33:24,400
Speaker 1: But I wonder if you could measure some other charge

725
00:33:24,400 --> 00:33:26,640
Speaker 1: of the Moon from a distance, could you? Or you

726
00:33:26,960 --> 00:33:29,600
Speaker 1: mentioned earlier, some signists are trying to do that. How

727
00:33:29,600 --> 00:33:31,239
Speaker 1: are they doing that and what kind of effect are

728
00:33:31,240 --> 00:33:32,280
Speaker 1: they using to measure this?

729
00:33:32,320 --> 00:33:35,120
Speaker 2: What they're doing is basically measuring the particles that come

730
00:33:35,240 --> 00:33:38,200
Speaker 2: off of the moon. Like you have something orbiting the moon.

731
00:33:38,280 --> 00:33:40,880
Speaker 2: You can collect particles, you can count, like how many

732
00:33:40,920 --> 00:33:43,400
Speaker 2: electrons are being pushed off of the positive side, how

733
00:33:43,400 --> 00:33:46,400
Speaker 2: many electrons are being lost on the negative side. Basically,

734
00:33:46,640 --> 00:33:48,680
Speaker 2: where are the particles and where are they going? And

735
00:33:48,720 --> 00:33:51,320
Speaker 2: then compare that to the model you have of what's

736
00:33:51,320 --> 00:33:53,640
Speaker 2: going on on the surface, and try to constrain it

737
00:33:53,640 --> 00:33:56,560
Speaker 2: and say, by measuring this many protons per second per

738
00:33:56,600 --> 00:34:00,160
Speaker 2: square centimeter up here, then how many are actually being

739
00:34:00,200 --> 00:34:02,840
Speaker 2: attracted to the moon or being pushed off of the moon.

740
00:34:03,280 --> 00:34:05,480
Speaker 1: Or I guess maybe to bring it down to Earth.

741
00:34:05,520 --> 00:34:06,840
Speaker 1: Like if I had an apple in front of me,

742
00:34:06,960 --> 00:34:09,040
Speaker 1: how would I measure whether it has a positive or

743
00:34:09,080 --> 00:34:09,800
Speaker 1: negative charge?

744
00:34:09,840 --> 00:34:12,120
Speaker 2: So the overall charge you can measure quite easily from

745
00:34:12,160 --> 00:34:15,000
Speaker 2: a distance. Right, you just have a test particle, You

746
00:34:15,040 --> 00:34:16,839
Speaker 2: put an electron near it, and you see the force

747
00:34:16,880 --> 00:34:19,080
Speaker 2: on that electron, and that will tell you the charge

748
00:34:19,080 --> 00:34:19,600
Speaker 2: of the apple.

749
00:34:20,160 --> 00:34:22,880
Speaker 1: What do you mean you test the force of an electron.

750
00:34:23,080 --> 00:34:25,080
Speaker 2: So if the apple is charged, it will create an

751
00:34:25,120 --> 00:34:27,720
Speaker 2: electric field, and that electric field would push or pull

752
00:34:27,800 --> 00:34:30,560
Speaker 2: on other charged particles. So if you want to measure

753
00:34:30,600 --> 00:34:32,760
Speaker 2: the charge of the apple, you basically need to measure

754
00:34:32,760 --> 00:34:34,799
Speaker 2: the strength of the field that it creates, and you

755
00:34:34,800 --> 00:34:37,360
Speaker 2: can do that by putting another particle in that field.

756
00:34:37,840 --> 00:34:39,600
Speaker 2: So if you have an electron, for example, and you

757
00:34:39,680 --> 00:34:42,719
Speaker 2: drop it near some object and you watch that electron move,

758
00:34:43,000 --> 00:34:45,560
Speaker 2: it'll tell you what the strength of the field is

759
00:34:45,600 --> 00:34:48,560
Speaker 2: moving through is because you'll see it bend or accelerate

760
00:34:48,719 --> 00:34:50,800
Speaker 2: or whatever, and that'll tell you the charge of the

761
00:34:50,840 --> 00:34:52,080
Speaker 2: object that made that field.

762
00:34:52,640 --> 00:34:54,759
Speaker 1: Could you do that with the Moon? Also? Like could

763
00:34:54,840 --> 00:34:57,319
Speaker 1: we not just like drop an electron near the Moon

764
00:34:57,360 --> 00:34:59,840
Speaker 1: and then figure out if it's positively or negatively?

765
00:35:00,440 --> 00:35:02,040
Speaker 2: Yeah, it's a cool question, and you could do that

766
00:35:02,120 --> 00:35:04,880
Speaker 2: if like there was a total vacuum, right, But everywhere

767
00:35:04,880 --> 00:35:08,040
Speaker 2: around the moon is a plasma. There's lots of positive

768
00:35:08,080 --> 00:35:10,640
Speaker 2: negative particles, So you can't just like isolate the moon.

769
00:35:11,120 --> 00:35:13,080
Speaker 2: And it comes down a little bit too like definition,

770
00:35:13,160 --> 00:35:14,560
Speaker 2: Like what do you mean by the moon? Do you

771
00:35:14,600 --> 00:35:16,960
Speaker 2: mean just the rocks that are made up you mean

772
00:35:17,000 --> 00:35:19,680
Speaker 2: also the exosphere? Do you mean this plasma sheet that

773
00:35:19,760 --> 00:35:20,960
Speaker 2: surrounds it as well?

774
00:35:21,360 --> 00:35:25,080
Speaker 1: Yes, to all of it. I mean I mean just

775
00:35:25,080 --> 00:35:27,200
Speaker 1: like if you stand away from the Moon a good

776
00:35:27,239 --> 00:35:29,680
Speaker 1: distance away, is it is it does overall have a

777
00:35:29,719 --> 00:35:32,359
Speaker 1: negative or positive charge. I mean, I thought that's kind

778
00:35:32,360 --> 00:35:33,480
Speaker 1: of what we're asking in this episode.

779
00:35:33,600 --> 00:35:35,960
Speaker 2: Yeah, I don't know if anybody's actually tried to measure

780
00:35:36,000 --> 00:35:39,799
Speaker 2: the overall charge of the Moon in that way. I'm

781
00:35:39,840 --> 00:35:42,680
Speaker 2: pretty sure it's close to zero. And we've measured the

782
00:35:42,840 --> 00:35:45,320
Speaker 2: charges on various sides of it and these processes and

783
00:35:45,400 --> 00:35:47,800
Speaker 2: understood that pretty well, and that all comes together to

784
00:35:47,840 --> 00:35:49,919
Speaker 2: tell you the story that the Moon is very likely

785
00:35:50,000 --> 00:35:53,240
Speaker 2: overall zero. But I don't know about an actual direct measurement,

786
00:35:53,560 --> 00:35:56,360
Speaker 2: Like we're talking about here dropping electrons somewhere near the

787
00:35:56,400 --> 00:35:57,920
Speaker 2: Moon and seeing what happens to them.

788
00:35:58,680 --> 00:36:00,239
Speaker 1: It sounds like somebody needs to go there, I know.

789
00:36:01,440 --> 00:36:04,000
Speaker 2: All right, everybody chip in for Jorges trip to the Moon.

790
00:36:04,960 --> 00:36:08,680
Speaker 1: Yeah, there you go, I'll pay for the electrons, now

791
00:36:08,800 --> 00:36:11,400
Speaker 1: go drop them off. All right. Well, what does this

792
00:36:11,480 --> 00:36:14,799
Speaker 1: mean about the Moon in general in kind of how

793
00:36:14,840 --> 00:36:16,440
Speaker 1: things are going in our solar system?

794
00:36:16,480 --> 00:36:19,040
Speaker 2: Well, it makes the Moon an even less pleasant place

795
00:36:19,200 --> 00:36:22,279
Speaker 2: to visit, because all the dust on there is very

796
00:36:22,360 --> 00:36:25,320
Speaker 2: very charged up, and it makes it really a pain,

797
00:36:25,600 --> 00:36:28,680
Speaker 2: like the dust tends to stick to everything. All the

798
00:36:28,680 --> 00:36:30,720
Speaker 2: experiments they did on the Moon and all the equipment

799
00:36:30,719 --> 00:36:34,400
Speaker 2: they brought came back like coded with this terrible regolith dust.

800
00:36:34,800 --> 00:36:37,000
Speaker 2: Everything on the Moon tends to stick because it all

801
00:36:37,000 --> 00:36:39,240
Speaker 2: gets charged up and it's a big mess.

802
00:36:39,560 --> 00:36:43,440
Speaker 1: Wait, why would dust stick if it's negatively charged? Wouldn't

803
00:36:43,480 --> 00:36:46,520
Speaker 1: be repelled by something neutral? Or would he care about

804
00:36:46,520 --> 00:36:48,000
Speaker 1: something neutral like my clothes?

805
00:36:48,080 --> 00:36:50,359
Speaker 2: For the same reason that like a balloon will stick

806
00:36:50,400 --> 00:36:52,799
Speaker 2: to your hair if you rub it enough. You know,

807
00:36:52,880 --> 00:36:55,520
Speaker 2: you are effectively shedding charges, and so you're building up

808
00:36:55,560 --> 00:36:59,480
Speaker 2: an overall electromagnetic force. And so the same thing happens

809
00:36:59,520 --> 00:37:00,800
Speaker 2: on the Moon all the time.

810
00:37:01,640 --> 00:37:03,840
Speaker 1: I see. So it's not easy to get rid of

811
00:37:03,840 --> 00:37:04,320
Speaker 1: this dust.

812
00:37:04,480 --> 00:37:08,080
Speaker 2: Yeah, exactly, But there are some positive sides. The fact

813
00:37:08,160 --> 00:37:11,640
Speaker 2: that the moon surface can be positively or negatively charged

814
00:37:12,000 --> 00:37:15,239
Speaker 2: might help us develop technology to explore or live on

815
00:37:15,280 --> 00:37:18,920
Speaker 2: the Moon. Is a group trying to build a levitating glider.

816
00:37:19,280 --> 00:37:21,319
Speaker 2: They're like, Hey, if dust can float on the Moon

817
00:37:21,400 --> 00:37:24,560
Speaker 2: using electromagnetism, why can't we build a device that like

818
00:37:24,640 --> 00:37:28,040
Speaker 2: floats on the moon, basically flying cars on the Moon? Mmm?

819
00:37:29,200 --> 00:37:31,080
Speaker 1: Like, use the fact that the surface of the Moon

820
00:37:31,160 --> 00:37:34,160
Speaker 1: is very charged, you know, positively on the light side,

821
00:37:34,200 --> 00:37:37,279
Speaker 1: negatively on the dark side, to maybe do like a

822
00:37:37,440 --> 00:37:38,360
Speaker 1: mac left train.

823
00:37:38,280 --> 00:37:40,439
Speaker 2: Yeah, except in this case would be like electro lev

824
00:37:40,520 --> 00:37:44,239
Speaker 2: I suppose the idea is to use an ion engine.

825
00:37:44,440 --> 00:37:46,960
Speaker 2: An ion engine is where you take like a neutral atom,

826
00:37:47,239 --> 00:37:50,439
Speaker 2: you know, a proton and an electron, you break them down,

827
00:37:50,480 --> 00:37:52,360
Speaker 2: you accelerate one of them and shoot them out the

828
00:37:52,400 --> 00:37:55,120
Speaker 2: back of the engine. So say, for example, you shoot

829
00:37:55,120 --> 00:37:57,120
Speaker 2: the electrons out the back of the engine. That's like

830
00:37:57,160 --> 00:37:59,360
Speaker 2: you're propellant. So you have a little rocket that's shooting

831
00:37:59,400 --> 00:38:01,480
Speaker 2: electrons the back and it gives you a little bit

832
00:38:01,520 --> 00:38:04,719
Speaker 2: of thrust. That's an ion engine. Well, one consequence of

833
00:38:04,760 --> 00:38:07,120
Speaker 2: throwing electrons out the back of your engine is now

834
00:38:07,120 --> 00:38:10,000
Speaker 2: your engine becomes positively charged. So if you're trying to

835
00:38:10,120 --> 00:38:12,920
Speaker 2: levitate over a positively charged surface, that gives you an

836
00:38:12,920 --> 00:38:15,880
Speaker 2: extra little boost. So you run your little engines, but

837
00:38:15,920 --> 00:38:18,560
Speaker 2: they don't have to be as powerful as normal because

838
00:38:18,560 --> 00:38:21,120
Speaker 2: now they're getting positively charged, so they're getting repelled by

839
00:38:21,200 --> 00:38:23,200
Speaker 2: the surface. So if you're going to build a little

840
00:38:23,239 --> 00:38:25,880
Speaker 2: glider to explore the Moon, you can take advantage of

841
00:38:25,920 --> 00:38:26,400
Speaker 2: this effect.

842
00:38:26,880 --> 00:38:29,040
Speaker 1: I see, figure out how to get rid of all

843
00:38:29,080 --> 00:38:35,200
Speaker 1: your electrons so that your car is positively charged, which

844
00:38:35,200 --> 00:38:38,400
Speaker 1: would make it float a little bit above the positively

845
00:38:38,480 --> 00:38:39,240
Speaker 1: charged moon.

846
00:38:39,080 --> 00:38:41,400
Speaker 2: Floor exactly, But then you're like Cinderella and you have

847
00:38:41,440 --> 00:38:43,680
Speaker 2: to watch out for the sunset because then your car

848
00:38:43,760 --> 00:38:45,000
Speaker 2: is going to slam into the surface.

849
00:38:45,040 --> 00:38:46,960
Speaker 1: When you get to the dark side, then the whole

850
00:38:47,760 --> 00:38:51,440
Speaker 1: surrounding floor turns negative exactly.

851
00:38:51,440 --> 00:38:53,120
Speaker 2: But then you just got to flip your ion engines

852
00:38:53,160 --> 00:38:55,640
Speaker 2: the other way and shoot the protons out of it

853
00:38:55,640 --> 00:38:58,279
Speaker 2: instead of the electrons, so it can work on either side.

854
00:38:58,760 --> 00:39:02,320
Speaker 1: But would that be enough gosh, I know the gravity

855
00:39:02,400 --> 00:39:04,759
Speaker 1: is lower on the Moon, but would it be enough

856
00:39:04,760 --> 00:39:06,080
Speaker 1: to actually make something flow?

857
00:39:06,440 --> 00:39:09,359
Speaker 2: Potentially? They're working on the technology and they've tested one

858
00:39:09,480 --> 00:39:12,280
Speaker 2: on Earth where they have like a one kilogram object

859
00:39:12,480 --> 00:39:15,280
Speaker 2: who was able to levitate a centimeter above the surface,

860
00:39:15,560 --> 00:39:18,880
Speaker 2: and they speculate that on future missions to very low

861
00:39:19,040 --> 00:39:22,600
Speaker 2: mass moons, very small moons, you might want a flyer

862
00:39:22,719 --> 00:39:25,760
Speaker 2: instead of a rover because rovers get stuck on surface effects,

863
00:39:26,239 --> 00:39:29,520
Speaker 2: and helicopters can be pretty tricky if there isn't enough atmosphere.

864
00:39:29,840 --> 00:39:33,480
Speaker 2: So they're thinking about developing these electrically levitating gliders for

865
00:39:33,640 --> 00:39:37,040
Speaker 2: exploring future small moons. We might want to figure out

866
00:39:37,080 --> 00:39:39,399
Speaker 2: if there's like alien life on or just figure out

867
00:39:39,400 --> 00:39:40,440
Speaker 2: what's on them.

868
00:39:40,440 --> 00:39:42,440
Speaker 1: I see, just to get around, because I guess wheels

869
00:39:42,920 --> 00:39:44,040
Speaker 1: can only get you so far.

870
00:39:44,200 --> 00:39:46,840
Speaker 2: Yeah, exactly. The glider doesn't get stuck in a crevass,

871
00:39:47,040 --> 00:39:49,279
Speaker 2: then it's easier to get over hills. You know. We

872
00:39:49,320 --> 00:39:51,840
Speaker 2: have these cool helicopter on Mars now and they're developing

873
00:39:51,840 --> 00:39:53,880
Speaker 2: one to fly on some of the moons of Jupiter.

874
00:39:54,160 --> 00:39:57,360
Speaker 2: But those are really good in higher atmosphere environments, and

875
00:39:57,400 --> 00:40:00,319
Speaker 2: this would work in a very low atmosphere environment moon.

876
00:40:00,719 --> 00:40:02,759
Speaker 1: All right, Well, it sounds like the answer to our

877
00:40:02,840 --> 00:40:05,319
Speaker 1: question today what's the electrical charge of the moon, is

878
00:40:05,360 --> 00:40:07,520
Speaker 1: that it depends on what side of the Moon you're in.

879
00:40:07,760 --> 00:40:10,240
Speaker 1: If you're in the light side, the charge is positive.

880
00:40:10,320 --> 00:40:12,719
Speaker 1: You're in dark side, it's negative. If you're in the

881
00:40:12,840 --> 00:40:17,200
Speaker 1: dusks or twilight zone, then things are neutral. But overall

882
00:40:17,640 --> 00:40:19,360
Speaker 1: it sounds like it's still kind of a mystery what

883
00:40:19,440 --> 00:40:20,960
Speaker 1: the charge of the whole moon is.

884
00:40:21,040 --> 00:40:24,400
Speaker 2: We think it's probably pretty close to zero, but we

885
00:40:24,440 --> 00:40:28,000
Speaker 2: don't have direct measurement using jorgees.

886
00:40:27,480 --> 00:40:30,839
Speaker 1: Electron right, right, and by we Daniel means Daniel.

887
00:40:30,640 --> 00:40:32,840
Speaker 2: That's right. I've not yet sent jorget to measure the

888
00:40:32,920 --> 00:40:34,680
Speaker 2: charge of the moon, so I don't have that data.

889
00:40:34,960 --> 00:40:37,239
Speaker 2: Nobody knows the exact charge of the.

890
00:40:37,120 --> 00:40:39,920
Speaker 1: Moon right now, all right, but I think it's another

891
00:40:40,040 --> 00:40:43,480
Speaker 1: interesting example of how complex things can get in the universe.

892
00:40:43,520 --> 00:40:45,879
Speaker 1: You know, you might think that something like the Doing

893
00:40:46,000 --> 00:40:48,080
Speaker 1: is just floating out there in space and it's made

894
00:40:48,080 --> 00:40:49,640
Speaker 1: out of neutral rocks, and so it must have a

895
00:40:49,640 --> 00:40:51,799
Speaker 1: neutral charge. But you know, there's so much going on

896
00:40:51,800 --> 00:40:54,600
Speaker 1: in the Solar system with the solar wind and gravity

897
00:40:54,760 --> 00:40:57,000
Speaker 1: and light and the photo electric effect, that things can

898
00:40:57,040 --> 00:40:59,319
Speaker 1: I get complicated and a little bit charged up.

899
00:40:59,400 --> 00:41:01,560
Speaker 2: Yeah, there's a lot more going on than just gravity

900
00:41:01,600 --> 00:41:05,520
Speaker 2: that shapes our solar system and our galaxy. These winds

901
00:41:05,560 --> 00:41:08,760
Speaker 2: affect our solar system, but there are also galactic winds

902
00:41:08,920 --> 00:41:12,000
Speaker 2: radiation from the center of the galaxy that shape the

903
00:41:12,040 --> 00:41:15,880
Speaker 2: structure of the galaxy and the star formation. So electromagnetism

904
00:41:16,040 --> 00:41:18,600
Speaker 2: still has things to say about the structure of the universe.

905
00:41:18,880 --> 00:41:20,960
Speaker 1: All right, Well, we hope you enjoyed that. Thanks for

906
00:41:21,000 --> 00:41:22,799
Speaker 1: joining us. See you next time.

907
00:41:27,320 --> 00:41:30,200
Speaker 2: For more science and curiosity. Come find us on social

908
00:41:30,239 --> 00:41:34,160
Speaker 2: media where we answer questions and post videos. We're on Twitter,

909
00:41:34,239 --> 00:41:37,600
Speaker 2: this word instant and now TikTok. Thanks for listening, and

910
00:41:37,680 --> 00:41:40,400
Speaker 2: remember that Daniel and Jorge Explain the Universe is a

911
00:41:40,440 --> 00:41:45,000
Speaker 2: production of iHeartRadio. For more podcasts from iHeartRadio, visit the

912
00:41:45,120 --> 00:41:49,279
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913
00:41:49,320 --> 00:41:50,080
Speaker 2: favorite shows.