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Speaker 1: Ang orgey. Does learning more about the universe make you

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Speaker 1: feel more or less safe?

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Speaker 2: I think it makes me feel small and insignificant, which

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Speaker 2: I guess is less.

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Speaker 1: Safe me too. The forces out there are just so

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Speaker 1: crazy and powerful. It's like it would take nothing to

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Speaker 1: squish us and wipe us out of existence.

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Speaker 2: But I hear there's a silver lining.

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Speaker 1: Oh yeah, what's that?

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Speaker 2: You know, as science progresses, maybe we figure out ways

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Speaker 2: to protect ourselves.

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Speaker 1: Hmmm. That sounds like a job for the engineers, not

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Speaker 1: the scientists.

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Speaker 2: Yeah, that's right. These scientists learn how we might die,

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Speaker 2: and engineers save us.

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Speaker 1: I'm totally happy with that division of labor.

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Speaker 2: Are you saying that engineers are superheroes?

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Speaker 1: That's no problem for me. I mean I hate wearing spandex.

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Speaker 2: Awesome, I have my cape ready.

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Speaker 1: Hi.

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Speaker 2: I am Poorhem, a cartoonist and the creator of PhD comics.

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Speaker 1: Hi, I'm Daniel. I'm a particle physicist and a professor

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Speaker 1: at UC Irvine, and science is my superpower.

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Speaker 2: The way you're not a superhero, you're a super villain

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Speaker 2: almost kind of like you're trying to figure out how

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Speaker 2: everyone might die.

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Speaker 1: Yeah, but I'm not shooting laser beams out of my

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Speaker 1: eyeballs and actually killing people. There's a distinction there.

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Speaker 2: What are you plotting? Are you plotting how to do it? Though?

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Speaker 1: I mean, if someone offered to make my eyeballs in

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Speaker 1: the laser beams, I would seriously consider it. I guess yeah.

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Speaker 2: I would make cooking easier, right, starting a fire while

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Speaker 2: when you're camping, also easier.

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Speaker 1: Doing the dishes, you know, frying that crusty stuff off

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Speaker 1: the bottom of pants, no need to soak it anymore.

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Speaker 2: That's right. Super villains have it easy.

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Speaker 1: But I do think it's incredible that we have this

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Speaker 1: power to understand the universe and unravel its true nature,

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Speaker 1: even if that does sometimes reveal great danger.

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Speaker 2: Although we always say that everyone is a physicist, which

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Speaker 2: technically means everybody has that superpower, which maybe makes it

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Speaker 2: not a superpower, just makes it a skill.

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Speaker 1: Is that like Superman on his planet Krypton, is not

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Speaker 1: really super at all, even if it's a planet of Superman.

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Speaker 2: Oh Man, Daniel, We've had this conversation. Everyone in Superman's

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Speaker 2: planet doesn't have powers because of the sun.

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Speaker 1: Oh, that's right, that's right. But if all of them

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Speaker 1: came to Earth, would they all then be superheroes. Is

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Speaker 1: there a limit to the number of superheroes you could have?

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Speaker 2: They would be super compared to us, So technically, yes,

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Speaker 2: they would be super. This is all a very philosophical conversation.

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Speaker 2: What is super?

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Speaker 1: Well, then we're all superheroes compared to like cats and dogs.

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Speaker 1: I can't do any.

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Speaker 2: Science, yes, I imagine. So yeah, to your dog, you

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Speaker 2: probably are a superhero. I mean you give it food,

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Speaker 2: magic food that just appears every day, twice a day.

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Speaker 1: And I don't even have to wear a cape.

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Speaker 2: And you also pick up their poop. I mean that's like,

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Speaker 2: that's like the best kind of superhero. But anyways, welcome

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Speaker 2: to our podcast Daniel and Jorge Explain the Universe, a

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Speaker 2: production of Our Heart Radio.

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Speaker 1: In which we dig into the deepest questions of the

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Speaker 1: nature of the universe, such as who is picking up

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Speaker 1: daniels dogs poop? And what's inside a black hole? And

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Speaker 1: can we use one question to solve the other one?

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Speaker 2: That's right, although I'm guessing that the answer to the

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Speaker 2: first question who picks up daniels dogs poop is Daniel.

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Speaker 2: I mean, it is your dog, it is.

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Speaker 1: My dog, and I'm very conscientious about it.

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Speaker 2: But yeah, it is an amazing universe, full of interesting

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Speaker 2: and crazy phenomena and mysteries and things for us to

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Speaker 2: discover and figure out with our puny, little human brains.

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Speaker 1: And many times when we explore the universe, we discover

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Speaker 1: fascinating facts about the way that it works. Sometimes we

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Speaker 1: can even put those facts to work to improve our lives.

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Speaker 1: Maybe one day someone will invent a black hole power

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Speaker 1: to dog poop picker upper. But sometimes we discover that

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Speaker 1: the universe is crazy and powerful and dangerous, that our

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Speaker 1: lives are a little bit more precarious and fragile than

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Speaker 1: we ever imagine.

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Speaker 2: Yeah, I guess if you think about it, we're just tiny,

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Speaker 2: little squishy beings living in a little thin layer of

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Speaker 2: air on a giant rock, hurling through space, barely not

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Speaker 2: falling into a giant ball of fire called the Sun.

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Speaker 1: Living right on the edge between being burned up and

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Speaker 1: being frozen to death. We are riding that knife edge

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Speaker 1: into infinity.

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Speaker 2: Yeah, it sort of makes you appreciate how precious life is, right,

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Speaker 2: or the fact that we're here to talk about the universe.

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Speaker 1: And how amazing that it's gone on for so long,

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Speaker 1: that the Earth has been habitable for billions of years,

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Speaker 1: even under vastly changing conditions. Over all that time, it's

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Speaker 1: been possible for these little squishy things to make more

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Speaker 1: squishy things.

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Speaker 2: Yeah, and I guess it also makes you think about

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Speaker 2: how precarious our existence is, and what are all the

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Speaker 2: things out there in the universe that could maybe end

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Speaker 2: our existence?

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Speaker 1: And even if there are crazy dangerous things out there

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Speaker 1: in the universe, I still want to know what they are,

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Speaker 1: not just because I have a deep curiosity for understanding

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Speaker 1: the nature of the universe, but because I'm hopefu that

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Speaker 1: if we can characterize what's going on out there in

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Speaker 1: the universe, eventually the engineers will save us.

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Speaker 2: Yeah. I guess that's the only way you might say

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Speaker 2: yourselves is if you know what's coming for you right

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Speaker 2: then you maybe we'll be able to do something about

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Speaker 2: it exactly.

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Speaker 1: That is why we track all the asteroids in the

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Speaker 1: Solar System and try to keep a handle on where

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Speaker 1: the comments are so that we can see one coming

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Speaker 1: with enough time to maybe divert it. That is why

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Speaker 1: we try to understand the nature of space and time

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Speaker 1: so that if a black hole does approach our Solar system,

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Speaker 1: and we'll have some ideas for how maybe to handle it.

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Speaker 2: Yeah, and it all starts with questions. And it's not

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Speaker 2: just scientists who have questions, it's everybody. Everybody has questions

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Speaker 2: about what's out there, what might affect them, what it

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Speaker 2: might change the way you live out there in the universe.

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Speaker 2: Everybody has questions.

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Speaker 1: That's right, and we love hearing your questions. If you

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Speaker 1: have thoughts and questions about the nature of the universe

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Speaker 1: and its future and how we might live in crazy

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Speaker 1: future times or strange corners of the universe, please don't

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Speaker 1: hesitate to write to us answer all of our questions.

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Speaker 1: Just email us at questions at Danielandjorge dot com.

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Speaker 2: So do they. On the podcast, we'll be tackling listener

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Speaker 2: questions number forty ways the universe could kill you. Addition,

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Speaker 2: I just.

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Speaker 1: Happen to notice when I was putting these together that

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Speaker 1: all of today's questions have something to do with very

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Speaker 1: powerful forces that could extinguish humanity.

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Speaker 2: Isn't that every physics question ever? I mean, is there

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Speaker 2: physics questions about something that would not totally annihilate humanity?

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Speaker 1: Sometimes it's just about everyday objects. Remember we had people

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Speaker 1: asking about like why does my truck look blue? And

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Speaker 1: how does the sun bleach my clothing and stuff like that?

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Speaker 1: Though I suppose there are cancer risks.

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Speaker 2: There, yes, radiation and chemicals. I mean maybe the more

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Speaker 2: you know, the more afraid it makes you.

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Speaker 1: I think it's something like a rorshark test. You know,

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Speaker 1: the way you look at the universe. Do you see

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Speaker 1: it as dangerous and crazy or do you see it

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Speaker 1: as fragile but still wonderful and lovingly supportive of our existence?

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Speaker 2: I see, like, is the universe half dangerous or half safe? Like,

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Speaker 2: if you have a fifty percent chance of surviving, is

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Speaker 2: that a good thing or a bad thing?

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Speaker 1: Yeah? Is the universe half trying to kill you or

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Speaker 1: half trying to save you? Or both?

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Speaker 2: I guess it depends on what it's like for dogs

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Speaker 2: and cats, and if it's better worse than us.

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Speaker 1: I think my dog, at least is a pretty good life.

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Speaker 2: But it is a pretty interesting topic. I guess people

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Speaker 2: are curious about what's out there and how it might,

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Speaker 2: you know, change our existence, and what can suddenly happen

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Speaker 2: to change our existence.

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Speaker 1: That's right, and so we're very excited to answer today's

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Speaker 1: questions all about the nature of space and time and

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Speaker 1: the whole universe and storms and dramatic supernova.

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Speaker 2: Yeah, we have three awesome questions here, and so let's

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Speaker 2: jump right in with the first question from Steve.

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Speaker 3: Hello, Daniel n Johe my name is Steve, and I

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Speaker 3: have a question about dark energy. You've mentioned on your

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Speaker 3: podcast previously that since we don't really you understand what

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Speaker 3: drives dark energy, it may be possible that the current

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Speaker 3: rate of expansion could at some point in the future

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Speaker 3: slow down and maybe even reverse, so that space starts

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Speaker 3: contracting rather than expanding. If this scenario did happen, My

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Speaker 3: question is, how would be first to take this?

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Speaker 2: Hmm, interesting question. I think Steve is saying that we

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Speaker 2: know that right now the universe is expanding, and it's

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Speaker 2: expanding faster and faster every day. But could that change,

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Speaker 2: Could somehow the universe stop expanding faster and faster and

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Speaker 2: maybe even start shrinking, In which case, when and how

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Speaker 2: would we even notice that that's?

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Speaker 1: Right? Could it be happening right now? And how could

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Speaker 1: we tell? Steve wants to know whether he should sell

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Speaker 1: his bitcoin or not.

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Speaker 2: Or real estate? Right? Should we buy more planets because

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Speaker 2: the universe is shrinking and real estate is going to

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Speaker 2: be a premium in the future or not. If the

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Speaker 2: universe is just going to keep growing, it's going to

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Speaker 2: be worth less and less.

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Speaker 1: This is a really pretty dark question because I don't

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Speaker 1: think there's anything the engineers could do to save you.

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Speaker 1: I mean, if the universe decides it's going to turn

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Speaker 1: around and crunch back to a super dense state, it's

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Speaker 1: pretty hard to imagine anybody surviving that.

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Speaker 2: It is a dark question also because it involves dark energy.

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Speaker 1: It does involve dark energy, and one of our favorite

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Speaker 1: topics the expansion of the universe and our almost total

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Speaker 1: lack of understanding for how it works, which makes it

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Speaker 1: pretty hard to predict what's going to happen in the future.

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Speaker 2: All right, well, let's dig into the answer to this question, Daniel.

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Speaker 2: I guess, first of all, how do we measure that

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Speaker 2: the universe is expanding?

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Speaker 1: Right? So Steve makes a good point, which is that

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Speaker 1: we are measuring the current rate of expansion, and then

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Speaker 1: we're extrapolating into the future and we're wondering about whether

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Speaker 1: that's going to change, and wondering about how we're going

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Speaker 1: to know that. So, yeah, let's think about how we

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Speaker 1: actually measure the expansion of the universe. And so what

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Speaker 1: we mean when we say the expansion of the universe

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Speaker 1: is we mean the increasing distances between galaxies. So we

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Speaker 1: look at our galaxy, and we look at other galleyalaxies,

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Speaker 1: and the best way to measure it, in principle would

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Speaker 1: be to pick a galaxy, measure our distance from it

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Speaker 1: and our speed relative to it, and then come back

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Speaker 1: a billion years later and say, Okay, where's that galaxy

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Speaker 1: now and how fast is it going. We can't do

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Speaker 1: that because it would take a billion years, and so

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Speaker 1: instead we do something different, which is that we look

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Speaker 1: further back in time for other galaxies and we say, well,

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Speaker 1: galaxies at a certain distance, which is a certain distance

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Speaker 1: back in time because of the propagation of light are

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Speaker 1: moving away from us at some velocity. And galaxies that

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Speaker 1: are further away, which is further back in time, back

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Speaker 1: in the history of the universe, how fast are they going?

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Speaker 1: So we can sort of read back the expansion of

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Speaker 1: the universe the velocity of galaxies relative to us versus distance,

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Speaker 1: which is also reading it versus time. Right.

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Speaker 2: But I guess the basics of it is that we're

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Speaker 2: measuring how fast galaxies are moving away from us. They'll

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Speaker 2: look like they're moving away from us, and we attribute

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Speaker 2: that to the expansion of the universe. And then you

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Speaker 2: want to check whether, like that that speed that the

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Speaker 2: galaxies are moved away from us, whether it's faster now

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Speaker 2: than it used to be, or whether it's lower than

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Speaker 2: it used to be, right exactly.

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Speaker 1: And to draw those conclusions, you need two pieces of

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Speaker 1: information per a galaxy. One is you have to know

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Speaker 1: how far away is it, so you basically know how

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Speaker 1: far back in time are we looking, and you have

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Speaker 1: to measure its velocity, how fast is it going relative

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Speaker 1: to us?

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Speaker 3: You know.

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Speaker 1: Something to understand also is that when you look out

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Speaker 1: into the sky, everything is moving away from us, except

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Speaker 1: for Andromeda, which is gravitationally dominated and moving towards us.

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Speaker 1: The overall picture is that everything is moving away from us.

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Speaker 1: And this is something that Hubble first noticed like one

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Speaker 1: hundred years ago, that if you look out into the sky,

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Speaker 1: everything is essentially red shifted because the light that comes

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Speaker 1: from these objects, its frequency is shifted towards the red

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Speaker 1: side of the spectrum. And that's how we measure the

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Speaker 1: velocity of these things. We look at the light from

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Speaker 1: a distant galaxy, we see how much it's shifted from

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Speaker 1: the light it should be sending us, and we use

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Speaker 1: that shift to measure its relative velocity.

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Speaker 2: Right, Because if it's moving away from us, light it

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Speaker 2: senses gets a little bit stretched out into the red spectrum, right,

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Speaker 2: And if something is moving towards us, the light gets

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Speaker 2: get a little bit compressed as it moves towards us

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Speaker 2: into the blue spectrum.

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Speaker 1: Right.

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Speaker 2: So the reder the light looks, the faster it's moving

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Speaker 2: away from.

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Speaker 1: Us, exactly. And there's two different ways to think about that.

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Speaker 1: One is that these galaxies have velocity relative to us,

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Speaker 1: and things that are in motion relative to us, their

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Speaker 1: light will be shifted, so it's called the Doppler shift.

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Speaker 1: The same way that like a police siren sounds different

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Speaker 1: as it passes you, because when it approaches you, its

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Speaker 1: sound waves are blue shifted to higher frequency, and when

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Speaker 1: it passes you, its sound waves are red shifted to

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Speaker 1: lower frequency. You can do the same sort of thinking

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Speaker 1: about the light from these galaxies. That's not one hundred

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Speaker 1: percent really the right way to think about it, because

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Speaker 1: these galaxies are so far away and it gives you

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Speaker 1: velocities greater than the speed of light. The way cosmologists

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Speaker 1: think about it instead is that space is expanding between

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Speaker 1: us and those galaxies, and so instead what's happening to

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Speaker 1: the light is that it's getting stretched out out by

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Speaker 1: space expanding, So the wavelengths get longer as the light

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Speaker 1: travels through space, and so that's why we'd see it

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Speaker 1: red shifted. So it's two different ways to think about

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Speaker 1: it that end up giving you exactly the same prediction.

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Speaker 1: Either you're measuring the expansion of space or you're measuring

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Speaker 1: the velocity of those galaxies relative to us.

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Speaker 2: It's the stretching of space itself that is changing the

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Speaker 2: color of the light.

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Speaker 1: Yeah, that's the way cosmologists think about it, because they

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Speaker 1: think about each galaxy as having like its own little

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Speaker 1: inertial frame. You could think about physics happening in those

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Speaker 1: galaxies and then between them space is expanding, and that's

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Speaker 1: why the light gets red shifted. And that avoids anything

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Speaker 1: being like faster than the speed of light because you

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Speaker 1: can't really compare velocities in one frame to velocities in

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Speaker 1: another frame. In general relativity, it gets really hairy.

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Speaker 2: All right. So then you said that we can look

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Speaker 2: back in history, in the history of the universe by

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Speaker 2: looking at galaxies that are further and further away from us,

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Speaker 2: And what we'd notice is that galaxies that are really

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Speaker 2: old move at a different rate away from for most

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Speaker 2: in galaxies that are younger.

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Speaker 1: Yeah, exactly, we can look at the velocity versus time,

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Speaker 1: and from that we can see how the velocity is

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Speaker 1: changing versus time, and so basically we're seeing whether the

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Speaker 1: universe's expansion is accelerating, speeding up, or whether it's decelerating,

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Speaker 1: whether it's slowing down. So we can see like the

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Speaker 1: history of the expansion velocity of the universe by looking

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Speaker 1: further and further back in time. Nearby galaxies are very recent,

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Speaker 1: they tell us about the expansion rate. Now, the very

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Speaker 1: very far away galaxies, the light from them we get

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Speaker 1: is very old. It's very out of date. But it's

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Speaker 1: sort of like looking at the fossil record. It's seeing

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Speaker 1: what was happening in the universe a long time ago.

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Speaker 1: So we can see the acceleration or deceleration history of

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Speaker 1: the universe.

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Speaker 2: Now, the fossils also turn red the older they get,

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Speaker 2: or is that why Like when you go to a

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Speaker 2: museum on the bones are brown? Where am I totally

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Speaker 2: misinforming our public.

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Speaker 1: Here. You got to get a paleontologist on here to

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Speaker 1: answer that question.

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Speaker 2: We need a paleophysicist.

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Speaker 1: Paleophysicist wow, a phrase I don't think I've ever heard before.

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Speaker 1: And who is picking up dinosaur poops? Really? Nobody was

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Speaker 1: cleaning up.

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Speaker 2: After the rest? Yeah, maybe it was a dinosaur. Physicists.

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Speaker 1: Paleophysicists should have been picking up those paleo poops. But

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Speaker 1: one thing I think is super fascinating and not really

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Speaker 1: widely enough appreciated, is that the universe has not always

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Speaker 1: been accelerating. Like, the universe has always been expanding, but

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Speaker 1: it hasn't always been accelerating, right.

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Speaker 2: There's been like periods when the universe was getting bigger

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Speaker 2: at a bigger rate or a slower rate.

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Speaker 1: Right Exactly. The sort of brief version of it is

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Speaker 1: that you have this very very super rapid inflation, very

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Speaker 1: early universe that we don't understand at all, but gives

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Speaker 1: you this huge universe with hot, dense plasma.

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Speaker 2: Does what we call the Big Bang? Right, sort of,

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Speaker 2: we're like right after the Big Bang.

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Speaker 1: So there's a bit of a disconnect in the terminology here.

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Speaker 1: What most people think of as the Big Bang is

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Speaker 1: that inflation that really rapid expansion very early on. What

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Speaker 1: scientists call the Big Bang is actually what happened after that.

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Speaker 1: Once you start from a very hot, dense place and

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Speaker 1: then you evolve that forwards in time. That's what we

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Speaker 1: mean when we say the Big Bang. We don't know

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Speaker 1: how we got that original very hot and dense state.

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Speaker 1: Maybe it was inflation, maybe it was something else. We

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Speaker 1: really just don't know. Big Bang starts from sort of

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Speaker 1: the Plank era, when the universe already existed and was

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Speaker 1: super hot and dense, and we evolve it forward in time.

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Speaker 1: That's sort of what we mean by the Big Bang.

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Speaker 1: It's sort of different from the popular conception of the

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Speaker 1: Big Bang.

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Speaker 2: Okay, but do you say there was an initial period

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Speaker 2: where the universe was expanding super fast?

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Speaker 1: Yeah, So we think probably inflation is this very rapid

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Speaker 1: expansion from quantum primordial soup to some very hot, dense state.

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Speaker 1: Then general relativity takes over and gravity and things cool

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Speaker 1: and expand, and we end up with the universe we

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Speaker 1: have today. Between the very hot and dense state and

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Speaker 1: where we are today. The universe has expanded a lot,

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Speaker 1: but it wasn't always accelerating. It was always expanding, but

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Speaker 1: for the first seven or eight billion years or so,

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Speaker 1: that expand was slowing down. But either there was enough

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Speaker 1: matter and energy in the universe to start pulling stuff

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Speaker 1: back together. Gravity was working hard to pull stuff back

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Speaker 1: together because of all that mass has gravity yanking on it.

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Speaker 1: But around eight billion years after the universe started, something changed.

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Speaker 1: Dark energy took over. This expansion of the universe slipped

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Speaker 1: from being decelerating to being accelerating. The expansion used to

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Speaker 1: be sort of slowing down, but then it turned over

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Speaker 1: and it started accelerating. So the last six or so

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Speaker 1: billion years of the universe we've had an accelerating expansion

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Speaker 1: of the universe. It's been going faster and faster.

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Speaker 2: It's like the universe hit the accelerator button or pedal.

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Speaker 1: Yeah, And it all comes down to the nature of

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Speaker 1: dark energy. Like as the universe expands, matter gets more dilute,

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Speaker 1: it gets more thinned out right, the same amount of matter,

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Speaker 1: and you have more space, and so things get more dilute.

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Speaker 1: But dark energy, we don't think it's like that. Dark

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Speaker 1: energy is a constant in space, and so as the

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Speaker 1: universe expands, you get more space, you get more dark energy.

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Speaker 1: So dark energy increases in its fraction of the universe

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Speaker 1: because everything else is getting more and more dilute, and

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Speaker 1: so eventually it takes over because as the universe expands,

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Speaker 1: it starts to win and it drives the expansion, and

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Speaker 1: so eventually it just takes over, and it's zooms so

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Speaker 1: far ahead that nobody can catch up to it. But

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Speaker 1: if you look back at the history of the universe

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Speaker 1: and you look at these diagrams and the expansion, you'll

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Speaker 1: notice that there was a time when the universe was

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Speaker 1: decelerating a little bit and before it started to zoom off.

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Speaker 3: Hmm.

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Speaker 1: Interesting.

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Speaker 2: Yeah, We've often talked about how dark energy the exceluration

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Speaker 2: of the universe changed, but it's I think what I'm

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Speaker 2: getting is that it like nothing really changed, Like dark

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Speaker 2: energy didn't suddenly turn on or some fundamental parameter of

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Speaker 2: the universe suddenly flipped. It's more like the density of

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Speaker 2: the universe got so sparse at some point that dark

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Speaker 2: energy just became more significant. Because dark energy, its power

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Speaker 2: is sort of proportional to how much space.

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Speaker 1: There is matter and energy is power gravitational is proportional

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Speaker 1: to its density, which drops as space gets bigger, and

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Speaker 1: that doesn't happen for dark energy. So you're right, the

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Speaker 1: rules didn't change, and what we think of as the

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Speaker 1: amount of dark energy in the universe didn't change. It's

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Speaker 1: just that things got so cold and dilute that eventually

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Speaker 1: dark energy sort of wins the tug of war.

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Speaker 2: But I wonder, like, if the universe had started with

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Speaker 2: more stuff, like more density of stuff. Is there a

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Speaker 2: universe in which thinks they're so dense that dark energy

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Speaker 2: always loses and things always compress.

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Speaker 1: Yeah, it's possible to have a closed universe like that

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Speaker 1: universe where you start with enough stuff that dark energy

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Speaker 1: doesn't win. Absolutely. You can start with different initial conditions

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Speaker 1: and you might end up with different outcome. Absolutely.

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Speaker 2: All right. Well, so thee's question is, what if that

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Speaker 2: acceleration of the universe slows down and even reverses, like

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Speaker 2: the universe starts to get smaller, there's less space every day.

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Speaker 2: Could we detect that and when would we detect that? Right,

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Speaker 2: that's a good question.

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Speaker 1: A super good question, and motivated by the fact that

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Speaker 1: everything we've said about dark energy so far is kind

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Speaker 1: of a guess, like we do not understand what dark

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Speaker 1: energy is. We have no like real theory for it

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Speaker 1: what we've talked about. So if our dark energy is

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Speaker 1: this constant in space and time, that's just really like

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Speaker 1: a hack. We just like put a number into the

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Speaker 1: equations and said, here's the number you got to put

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Speaker 1: in to make the equations work. We don't know where

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Speaker 1: that number comes from. We don't know why that number

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Speaker 1: would be constant. We just like use the number because

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Speaker 1: that's the simplest description. And the point is that that

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Speaker 1: could change. And what if in the future it does,

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Speaker 1: and it changes to another value, and it changes to

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Speaker 1: a smaller value, goes away, so that gravity then does

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Speaker 1: win and the universe does take over, or if it

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Speaker 1: changes in such a way that it works in the

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Speaker 1: opposite direction to compress the universe. Basically, because we don't

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Speaker 1: know what's going on, we can't make any predictions about

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Speaker 1: what's going to happen in the future. And so Save's

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Speaker 1: question is great. It's like, how would we observe a change,

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Speaker 1: How would we notice that things deviate from this simple prediction?

441
00:20:45,760 --> 00:20:47,440
Speaker 1: And it would be hard. The first clues we would

442
00:20:47,520 --> 00:20:51,160
Speaker 1: have would be for nearby stuff, right, stuff that's really

443
00:20:51,200 --> 00:20:53,280
Speaker 1: really far away. We're not going to get messages from

444
00:20:53,280 --> 00:20:57,200
Speaker 1: that for a long time. But closer by stuff, nearby

445
00:20:57,320 --> 00:20:59,840
Speaker 1: galaxies and galaxy clusters, those are the ones that are

446
00:20:59,840 --> 00:21:03,119
Speaker 1: telling us about the recent history of the universe, but

447
00:21:03,240 --> 00:21:05,439
Speaker 1: how things are expanding right now or at least in

448
00:21:05,440 --> 00:21:08,200
Speaker 1: the very recent past. So if we watch very carefully

449
00:21:08,240 --> 00:21:10,520
Speaker 1: the closer stuff, that's where we could see like a

450
00:21:10,680 --> 00:21:13,760
Speaker 1: change in the slope, like if things are accelerating less

451
00:21:13,840 --> 00:21:16,320
Speaker 1: or more, or if it's even started to decelerate.

452
00:21:16,560 --> 00:21:19,159
Speaker 2: Oh, I think you're saying that, Like, if the universe

453
00:21:19,200 --> 00:21:23,080
Speaker 2: starts to decelerate, right's expand slower, it's going to happen

454
00:21:23,280 --> 00:21:25,879
Speaker 2: all throughout the universe at the same time. And so

455
00:21:26,040 --> 00:21:28,480
Speaker 2: it's going to happen now, and it's going to happen

456
00:21:28,520 --> 00:21:31,480
Speaker 2: to the galaxies that are really really far away. So

457
00:21:31,480 --> 00:21:34,560
Speaker 2: if it all happens at the same time, then the

458
00:21:34,600 --> 00:21:36,840
Speaker 2: freshest news we would get up of it would be

459
00:21:36,840 --> 00:21:37,800
Speaker 2: from the nearby stuff.

460
00:21:37,880 --> 00:21:39,879
Speaker 1: Yeah, and that's also an assumption, right there could be

461
00:21:39,880 --> 00:21:42,600
Speaker 1: like weird bubbles. Maybe it doesn't happen everywhere in the universe,

462
00:21:42,640 --> 00:21:45,800
Speaker 1: But the simplest model is, like, let's assume that something

463
00:21:45,880 --> 00:21:48,760
Speaker 1: changes in the whole parameter of the universe everywhere at once,

464
00:21:48,800 --> 00:21:51,159
Speaker 1: and so we wouldn't notice it from really far away

465
00:21:51,200 --> 00:21:54,720
Speaker 1: galaxies very quickly. We'd notice it from nearby galaxies. As

466
00:21:54,760 --> 00:21:56,879
Speaker 1: you say, that's the freshest news. And so we'd have

467
00:21:56,920 --> 00:22:00,560
Speaker 1: to notice a change in the relative velocities of nearby

468
00:22:00,720 --> 00:22:04,320
Speaker 1: galaxies that their velocity away from us is decreasing instead

469
00:22:04,320 --> 00:22:07,560
Speaker 1: of increasing, Like if things nearby start to blue shift

470
00:22:07,600 --> 00:22:10,240
Speaker 1: instead of red shift, we'd be like, WHOA, that's weird.

471
00:22:10,200 --> 00:22:11,760
Speaker 2: Right, But I guess if you're assuming that it all

472
00:22:11,840 --> 00:22:15,400
Speaker 2: happens at the same time, wouldn't it already have happened

473
00:22:15,440 --> 00:22:16,840
Speaker 2: to stuff that's really far away.

474
00:22:17,000 --> 00:22:18,800
Speaker 1: If it's happening all at the same time, then it

475
00:22:18,840 --> 00:22:21,320
Speaker 1: happens also to stuff that's really far away. We wouldn't

476
00:22:21,320 --> 00:22:23,879
Speaker 1: see any evidence of it for a long time. Like

477
00:22:23,920 --> 00:22:26,359
Speaker 1: we can't see right now what's happening for stuff really

478
00:22:26,359 --> 00:22:28,600
Speaker 1: really far away, we won't see that for a long

479
00:22:28,640 --> 00:22:30,560
Speaker 1: long time because it's so far away.

480
00:22:31,680 --> 00:22:33,439
Speaker 2: So that's good. We would know right away if the

481
00:22:33,520 --> 00:22:34,960
Speaker 2: universe was slowing down.

482
00:22:35,080 --> 00:22:37,800
Speaker 1: Yeah, that's true, although the nearest galaxies are even not

483
00:22:37,960 --> 00:22:41,680
Speaker 1: that nearby, and the closest galaxies are dominated by gravity

484
00:22:41,720 --> 00:22:44,560
Speaker 1: like Andromeda in the Milky Way, are actually approaching each

485
00:22:44,560 --> 00:22:47,480
Speaker 1: other because of their relative gravity. So what you'd have

486
00:22:47,520 --> 00:22:49,640
Speaker 1: to do is look far enough away that you're looking

487
00:22:49,680 --> 00:22:52,679
Speaker 1: at stuff where dark energy is really dominant. That's like

488
00:22:52,720 --> 00:22:56,240
Speaker 1: between galaxy clusters, so it wouldn't even be that nearby.

489
00:22:56,480 --> 00:22:58,960
Speaker 1: So now we're talking about like tens or hundreds of

490
00:22:59,000 --> 00:23:02,320
Speaker 1: millions of light years away these galaxies, which means if

491
00:23:02,359 --> 00:23:05,120
Speaker 1: the universe starts to turn around and compress, we wouldn't

492
00:23:05,160 --> 00:23:08,480
Speaker 1: know for tens or hundreds of millions of years.

493
00:23:08,359 --> 00:23:10,479
Speaker 2: Right, But I guess there's some comfort to know that

494
00:23:10,720 --> 00:23:14,600
Speaker 2: we're looking at galaxies that are, you know, thirteen billion

495
00:23:14,720 --> 00:23:18,520
Speaker 2: years old, and so far it doesn't look like the

496
00:23:18,640 --> 00:23:22,680
Speaker 2: universe is compressing, right, So like, why would it suddenly change?

497
00:23:22,760 --> 00:23:25,320
Speaker 1: Now, Yeah, we have no reason to suspect that it will,

498
00:23:25,560 --> 00:23:28,840
Speaker 1: but we also don't understand what's going on really at all.

499
00:23:28,960 --> 00:23:31,359
Speaker 1: So you're right, the simplest model is to just extractly

500
00:23:31,440 --> 00:23:35,479
Speaker 1: continued accelerating expansion, So don't worry about this if you're

501
00:23:35,520 --> 00:23:37,920
Speaker 1: an anxious person. But the truth is that we don't

502
00:23:37,960 --> 00:23:40,679
Speaker 1: really have a reason to believe that, and so the

503
00:23:40,760 --> 00:23:43,760
Speaker 1: universe has surprised us many times in the past. And

504
00:23:43,920 --> 00:23:47,000
Speaker 1: remember this whole idea of accelerating expansion was also a surprise.

505
00:23:47,320 --> 00:23:50,600
Speaker 1: Nobody expected that at all, so there probably are more

506
00:23:50,640 --> 00:23:51,840
Speaker 1: surprises in store.

507
00:23:52,560 --> 00:23:55,000
Speaker 2: I think what you're saying is that engineers could say

508
00:23:55,080 --> 00:23:56,680
Speaker 2: was in the future. We don't know yet.

509
00:23:58,480 --> 00:24:01,680
Speaker 4: We should keep funding engineers. Yes, I totally agree, that's right.

510
00:24:01,760 --> 00:24:03,560
Speaker 4: Keep us around please. All right, Well, I think that

511
00:24:03,640 --> 00:24:06,440
Speaker 4: answers Steve's question. How would we first detected, Well, we

512
00:24:06,480 --> 00:24:09,000
Speaker 4: would detect it in the galaxies that are closest to us.

513
00:24:09,040 --> 00:24:11,960
Speaker 4: If there is sort of a universe wide shift in

514
00:24:12,040 --> 00:24:15,200
Speaker 4: how things are expanding, we would know right away from

515
00:24:15,200 --> 00:24:17,840
Speaker 4: where if the things around us are expanding faster, or

516
00:24:17,840 --> 00:24:20,359
Speaker 4: if they're starting to creep in a little bit more

517
00:24:20,400 --> 00:24:22,399
Speaker 4: each day, then we would know. All right, let's get

518
00:24:22,440 --> 00:24:24,920
Speaker 4: to our other two questions. We have an awesome question

519
00:24:25,000 --> 00:24:28,040
Speaker 4: about supernovas, or I guess kind of a deadly question

520
00:24:28,119 --> 00:24:32,679
Speaker 4: about supernovas, and about danger storms in our solar system.

521
00:24:32,840 --> 00:24:35,479
Speaker 2: Let's get to those. But first, let's take a quick break.

522
00:24:47,960 --> 00:24:50,880
Speaker 2: All right, we are answering listener questions, and I guess

523
00:24:50,920 --> 00:24:55,080
Speaker 2: these are very worried listener questions. Our listeners are worried

524
00:24:55,119 --> 00:24:58,760
Speaker 2: about how the universe might end human existence.

525
00:24:58,560 --> 00:25:01,919
Speaker 1: Or they're just in awe the crazy power out there

526
00:25:01,960 --> 00:25:04,320
Speaker 1: in astronomical and after physical objects.

527
00:25:04,880 --> 00:25:08,280
Speaker 2: You're shocked and odd. All right? Our next question comes

528
00:25:08,280 --> 00:25:12,080
Speaker 2: from christof and it's about supernova's. Dear Daniel, I have

529
00:25:12,200 --> 00:25:14,760
Speaker 2: always wondered what would happen to the Earth if there

530
00:25:14,840 --> 00:25:16,040
Speaker 2: was a super and nova nearby?

531
00:25:16,440 --> 00:25:16,880
Speaker 1: Thanks?

532
00:25:17,200 --> 00:25:20,440
Speaker 2: We would all die? Done? Next question?

533
00:25:20,520 --> 00:25:21,960
Speaker 1: Oh, let's give him a little bit of hope.

534
00:25:21,960 --> 00:25:26,600
Speaker 2: Come on, that's right. Yes, it depends on which side

535
00:25:26,640 --> 00:25:30,240
Speaker 2: of the Earth you're in. Maybe hopefully it's like nighttime

536
00:25:30,680 --> 00:25:32,800
Speaker 2: or you're sleeping when it happens.

537
00:25:32,920 --> 00:25:35,320
Speaker 1: That's only if the supernova is brief enough to only

538
00:25:35,400 --> 00:25:36,880
Speaker 1: last during somebody else's night.

539
00:25:37,040 --> 00:25:39,960
Speaker 2: Mmmm A, right, let's dig into it. I guess the

540
00:25:40,040 --> 00:25:42,640
Speaker 2: question is what would happen even supernova if a star

541
00:25:42,760 --> 00:25:47,280
Speaker 2: explodes nearby us? Would we have a chance of surviving?

542
00:25:47,400 --> 00:25:47,480
Speaker 3: Or?

543
00:25:47,520 --> 00:25:50,720
Speaker 2: I guess also, how likely is that to happen to us?

544
00:25:50,920 --> 00:25:55,000
Speaker 1: Yes? So to understand the amazing, incredible power of a supernova,

545
00:25:55,080 --> 00:25:57,480
Speaker 1: you have to understand what we're talking about here. What

546
00:25:57,680 --> 00:26:00,679
Speaker 1: is the supernova? Where does its energy come from? And

547
00:26:00,800 --> 00:26:04,960
Speaker 1: a supernova is essentially the end point of really massive stars.

548
00:26:05,119 --> 00:26:07,480
Speaker 1: They burn their hydrogen to make helium. They burn their

549
00:26:07,480 --> 00:26:10,760
Speaker 1: helium to make heavier stuff. They burn carbon, they burn oxygen,

550
00:26:10,840 --> 00:26:14,240
Speaker 1: they burn nitrogen. Eventually they get really really heavy. They

551
00:26:14,240 --> 00:26:17,040
Speaker 1: have accumulated all this really heavy metal in their core,

552
00:26:17,240 --> 00:26:20,800
Speaker 1: and gravity gets so powerful inside these stars that it

553
00:26:20,840 --> 00:26:24,240
Speaker 1: can no longer be resisted by the pressure of that fusion.

554
00:26:24,640 --> 00:26:27,479
Speaker 1: And all that energy flying out has been puffing up

555
00:26:27,480 --> 00:26:30,080
Speaker 1: the star keeping it from collapsing. So you get this

556
00:26:30,160 --> 00:26:33,359
Speaker 1: million or billion year long struggle between gravity trying to

557
00:26:33,400 --> 00:26:36,800
Speaker 1: compress the star and fusion resisting it. But eventually gravity

558
00:26:36,880 --> 00:26:39,000
Speaker 1: is going to win that battle, and you get this

559
00:26:39,080 --> 00:26:42,200
Speaker 1: incredible compression of the star, this collapse of the star

560
00:26:42,280 --> 00:26:44,960
Speaker 1: we call it a core collapse, which leads to very

561
00:26:45,040 --> 00:26:48,639
Speaker 1: very high temperatures inside the star, which triggers this brief

562
00:26:48,760 --> 00:26:52,160
Speaker 1: moment of super intense fusion, which then explodes the star.

563
00:26:52,400 --> 00:26:55,280
Speaker 1: So you get this gravitational collapse followed by this very

564
00:26:55,359 --> 00:26:59,640
Speaker 1: dramatic explosion. And in that explosion, the supernova gives off

565
00:26:59,680 --> 00:27:03,240
Speaker 1: soul much energy that it can outshine the entire galaxy

566
00:27:03,280 --> 00:27:06,320
Speaker 1: that it's in. Right, a single supernova can be as

567
00:27:06,359 --> 00:27:10,239
Speaker 1: bright or brighter than like one hundred billion stars in

568
00:27:10,320 --> 00:27:11,400
Speaker 1: the galaxy that it's in.

569
00:27:11,680 --> 00:27:12,840
Speaker 2: Yeah, it's a big explosion.

570
00:27:13,000 --> 00:27:14,720
Speaker 1: It's a big explosion.

571
00:27:14,240 --> 00:27:17,160
Speaker 2: And it's basically it's sort of like if a building collapses,

572
00:27:17,640 --> 00:27:20,159
Speaker 2: but the building is full of dynamite, kind of right, Like,

573
00:27:20,240 --> 00:27:23,879
Speaker 2: it collapses and then the wind it crunches down together.

574
00:27:24,080 --> 00:27:27,320
Speaker 2: Things get exciting and the explode and then everything flies out.

575
00:27:27,440 --> 00:27:29,880
Speaker 1: Yeah, it's actually a pretty good model for how hydrogen

576
00:27:29,920 --> 00:27:34,440
Speaker 1: bombs work. Hydrogen bombs are fusion bombs, but the conditions

577
00:27:34,480 --> 00:27:38,720
Speaker 1: for fusion are created by a fission bomb, which implodes

578
00:27:38,800 --> 00:27:41,640
Speaker 1: the fusion fuel. So you get this fission bomb which

579
00:27:41,680 --> 00:27:44,720
Speaker 1: blows up and then squeezes the fuel for fusion, which

580
00:27:44,760 --> 00:27:48,880
Speaker 1: then triggers the more dramatic fusion bomb. And that's basically

581
00:27:48,920 --> 00:27:51,560
Speaker 1: what's going on inside of supernova, except the fuel pellet

582
00:27:51,600 --> 00:27:53,600
Speaker 1: is like the size of a star, and so that's

583
00:27:53,600 --> 00:27:56,359
Speaker 1: what we call a type two supernova. There's also another

584
00:27:56,480 --> 00:27:59,840
Speaker 1: kind which are even brighter, even more dangerous and more

585
00:28:00,080 --> 00:28:02,640
Speaker 1: deadly to life on Earth, which is a type one.

586
00:28:03,160 --> 00:28:05,560
Speaker 1: That's the kind of star that originally wasn't going to

587
00:28:05,640 --> 00:28:09,119
Speaker 1: go supernova. It burned and accumulated these hot metals at

588
00:28:09,119 --> 00:28:12,080
Speaker 1: its core, but not enough so that gravity would take

589
00:28:12,119 --> 00:28:16,879
Speaker 1: over and actually collapse until some other source of fuel

590
00:28:16,880 --> 00:28:20,480
Speaker 1: comes by, some like red giant in a binary star

591
00:28:20,520 --> 00:28:22,800
Speaker 1: system with this white dwarf, and the white dwarf steals

592
00:28:22,800 --> 00:28:25,359
Speaker 1: a little bit more fuel, which gets it heavy enough

593
00:28:25,560 --> 00:28:29,000
Speaker 1: for gravity to overcome this threshold and then trigger a collapse.

594
00:28:29,359 --> 00:28:31,639
Speaker 1: That's a type one supernova, and they can be like

595
00:28:31,760 --> 00:28:34,200
Speaker 1: ten times as bright as a type two supernova.

596
00:28:34,640 --> 00:28:37,480
Speaker 2: M that's interesting, I guess the question is why is that?

597
00:28:37,640 --> 00:28:41,240
Speaker 2: Why is it brighter and more explosive if it's sort

598
00:28:41,280 --> 00:28:43,800
Speaker 2: of like the same amount of stuff being exploded.

599
00:28:43,880 --> 00:28:47,000
Speaker 1: So we don't really understand very well exactly what's going

600
00:28:47,040 --> 00:28:49,440
Speaker 1: on inside supernova. So this is sort of an area

601
00:28:49,480 --> 00:28:52,560
Speaker 1: of current research. People speculate that, like the amount of

602
00:28:52,640 --> 00:28:56,360
Speaker 1: coalbalt inside these things might be enough to trigger more

603
00:28:56,440 --> 00:28:59,240
Speaker 1: dramatic reactions it, or at least more energy, but it's

604
00:28:59,280 --> 00:29:01,880
Speaker 1: really sort of a area of fuzzy understanding. So far,

605
00:29:01,960 --> 00:29:04,920
Speaker 1: we don't even understand exactly when a star will go supernova.

606
00:29:04,960 --> 00:29:08,040
Speaker 1: It's the exact thing that triggers this collapse. It's not

607
00:29:08,160 --> 00:29:10,920
Speaker 1: something that we understand very well yet. So this is

608
00:29:10,920 --> 00:29:12,920
Speaker 1: something we're still trying to figure out. A lot of

609
00:29:12,920 --> 00:29:15,480
Speaker 1: this stuff is just descriptive, Like we see these kind

610
00:29:15,480 --> 00:29:17,960
Speaker 1: of things in the universe, and we so describe these

611
00:29:17,960 --> 00:29:20,320
Speaker 1: one way and we describe these another way. We don't

612
00:29:20,360 --> 00:29:23,240
Speaker 1: always understand the mechanisms and the underlying science.

613
00:29:23,440 --> 00:29:25,840
Speaker 2: I guess maybe a follow question is like how do

614
00:29:25,920 --> 00:29:28,000
Speaker 2: we know that they're different? I mean, I imagine we

615
00:29:28,080 --> 00:29:29,800
Speaker 2: saw some things blow up in the sky and we

616
00:29:29,840 --> 00:29:33,080
Speaker 2: saw somewhere them are bigger and smaller than others. How

617
00:29:33,120 --> 00:29:35,080
Speaker 2: do we know like, oh, this is a totally different

618
00:29:35,200 --> 00:29:36,000
Speaker 2: kind of explosion.

619
00:29:36,200 --> 00:29:38,480
Speaker 1: Yeah, it comes down to categorizing. We are like looking

620
00:29:38,480 --> 00:29:40,800
Speaker 1: at these things and we're tracing their light curves, and

621
00:29:40,800 --> 00:29:43,880
Speaker 1: then we're looking back through our records to find the progenitor,

622
00:29:43,960 --> 00:29:46,360
Speaker 1: like what was the thing that led to this? Was

623
00:29:46,400 --> 00:29:49,240
Speaker 1: it a big red star or was it a white dwarf?

624
00:29:49,280 --> 00:29:51,600
Speaker 1: And we don't know what's going to go supernova? So

625
00:29:51,640 --> 00:29:53,880
Speaker 1: you can't just like watch one and see it happen.

626
00:29:54,200 --> 00:29:56,720
Speaker 1: You have to go backwards. You see, oh we saw supernova.

627
00:29:56,840 --> 00:29:58,680
Speaker 1: Now let's go back and see what used to be

628
00:29:58,760 --> 00:30:01,520
Speaker 1: there in the sky. And so if it was a

629
00:30:01,640 --> 00:30:04,040
Speaker 1: red giant, then you're going to call it a core collapse.

630
00:30:04,160 --> 00:30:05,920
Speaker 1: If it was a white dwarf, and there was a

631
00:30:05,960 --> 00:30:08,720
Speaker 1: red giant nearby that it was stealing matter from. You're

632
00:30:08,720 --> 00:30:10,600
Speaker 1: going to call that a type one supernova.

633
00:30:10,640 --> 00:30:13,520
Speaker 2: And then if it's really particular about every little detail

634
00:30:13,520 --> 00:30:17,280
Speaker 2: of the explosion, then it's a Type A supernova.

635
00:30:17,360 --> 00:30:19,440
Speaker 1: If it just got to be the biggest supernova in

636
00:30:19,480 --> 00:30:22,120
Speaker 1: the galaxy, no matter what, then yeah, exactly.

637
00:30:22,600 --> 00:30:25,840
Speaker 2: The very competitive. If it's a super dupernova.

638
00:30:25,640 --> 00:30:27,320
Speaker 1: It's a tiger supernova exactly.

639
00:30:27,600 --> 00:30:29,920
Speaker 2: All right, Well, let's get to Christof's question, which is

640
00:30:29,960 --> 00:30:33,320
Speaker 2: what would happen if one of these stars, either a

641
00:30:33,400 --> 00:30:36,600
Speaker 2: red giant or white dwarf, it explodes near us? What

642
00:30:36,640 --> 00:30:39,000
Speaker 2: would happen to Earth? Like, First of all, what are

643
00:30:39,000 --> 00:30:40,240
Speaker 2: the chances of that happening?

644
00:30:40,360 --> 00:30:43,880
Speaker 1: It's very unlikely because supernova, first of all, are very rare,

645
00:30:44,360 --> 00:30:47,240
Speaker 1: Like we think that maybe one in every few million

646
00:30:47,400 --> 00:30:51,600
Speaker 1: stars will go supernova just because massive stars starts big

647
00:30:51,680 --> 00:30:54,200
Speaker 1: enough to have this happen are pretty rare. Most of

648
00:30:54,240 --> 00:30:56,719
Speaker 1: the stars in the universe are colder and smaller than

649
00:30:56,760 --> 00:30:59,680
Speaker 1: stars that will go supernova. They're even mostly colder and

650
00:30:59,720 --> 00:31:02,520
Speaker 1: small more than our star. So most of these stars

651
00:31:02,560 --> 00:31:05,040
Speaker 1: are red dwarfs, and they will end up making white

652
00:31:05,120 --> 00:31:08,040
Speaker 1: dwarfs and they will not go supernova. In fact, they're

653
00:31:08,080 --> 00:31:10,600
Speaker 1: so rare that we haven't even seen a supernova in

654
00:31:10,720 --> 00:31:13,440
Speaker 1: our galaxy in four hundred years.

655
00:31:14,080 --> 00:31:16,880
Speaker 2: They're that rare, so they're not likely to happen. But

656
00:31:16,920 --> 00:31:19,760
Speaker 2: I don't think that's why it keeps people up. I

657
00:31:19,760 --> 00:31:21,800
Speaker 2: guess maybe let's think about it, like, what's the closest

658
00:31:21,800 --> 00:31:24,680
Speaker 2: star to us, and what's the likelihood that it will

659
00:31:24,760 --> 00:31:25,480
Speaker 2: go supernova?

660
00:31:25,640 --> 00:31:28,080
Speaker 1: Yeah, so the closest star to us is Proximist Centari,

661
00:31:28,200 --> 00:31:30,120
Speaker 1: and it's a pretty low mass star. It's much more

662
00:31:30,160 --> 00:31:33,600
Speaker 1: typical than our star. It's like twelve percent of the

663
00:31:33,640 --> 00:31:36,280
Speaker 1: mass of the Sun. So that thing is definitely not

664
00:31:36,360 --> 00:31:38,480
Speaker 1: going to go supernova.

665
00:31:37,840 --> 00:31:40,000
Speaker 2: Right, Like a star needs to be a certain size

666
00:31:40,040 --> 00:31:42,880
Speaker 2: for it to go even think about going supernova, and

667
00:31:42,960 --> 00:31:46,280
Speaker 2: like our Sun and Proximus Centari are not they'll qualify

668
00:31:46,440 --> 00:31:47,680
Speaker 2: for supernova's status.

669
00:31:47,920 --> 00:31:50,040
Speaker 1: To really even have any chance to go supernova, you

670
00:31:50,040 --> 00:31:52,360
Speaker 1: need to have like eight to ten times the mass

671
00:31:52,360 --> 00:31:54,640
Speaker 1: of the Sun. I remember, the Sun is already an

672
00:31:54,720 --> 00:31:58,160
Speaker 1: unusually massive star, and so ten times the mass of

673
00:31:58,160 --> 00:32:01,000
Speaker 1: the Sun is even less likely. The more mass of

674
00:32:01,040 --> 00:32:04,200
Speaker 1: the star, the much less common they are. There are

675
00:32:04,320 --> 00:32:07,720
Speaker 1: some sort of nearby stars. For example, there's a star

676
00:32:07,840 --> 00:32:12,040
Speaker 1: named Speaker, which is eighty parsecs away, that's like two

677
00:32:12,160 --> 00:32:14,320
Speaker 1: hundred and fifty light years and its mass is a

678
00:32:14,320 --> 00:32:16,840
Speaker 1: little uncertain, but you know, order of magnitude about ten

679
00:32:16,960 --> 00:32:20,320
Speaker 1: times the mass of the Sun, and so that's a candidate,

680
00:32:20,560 --> 00:32:22,840
Speaker 1: you know, but it's two hundred and fifty light years away.

681
00:32:23,520 --> 00:32:26,000
Speaker 2: Right. There's some sort of list out there right of

682
00:32:26,040 --> 00:32:28,040
Speaker 2: like of the stars that we can see that are

683
00:32:28,080 --> 00:32:31,480
Speaker 2: closest to us, which of these stars are big enough

684
00:32:31,480 --> 00:32:34,200
Speaker 2: to maybe go supernova. There's like a list out there, right.

685
00:32:34,080 --> 00:32:36,800
Speaker 1: There is a list exactly, and so Speaker is one

686
00:32:36,800 --> 00:32:40,080
Speaker 1: of them. Another one is Beetlejuice. Right, Beetlejuice is like

687
00:32:40,200 --> 00:32:43,320
Speaker 1: six hundred light years away, but is a pretty massive star.

688
00:32:43,360 --> 00:32:45,600
Speaker 1: It's like maybe up to twenty times the mass of

689
00:32:45,640 --> 00:32:48,280
Speaker 1: the Sun. And so these things are candidates. And again,

690
00:32:48,320 --> 00:32:52,120
Speaker 1: because we don't know exactly what triggers the supernova, like

691
00:32:52,120 --> 00:32:54,520
Speaker 1: what are the conditions to make this happen, we can't

692
00:32:54,560 --> 00:32:56,479
Speaker 1: look at Beetlejuice and be like, oh, this one is

693
00:32:56,680 --> 00:32:59,320
Speaker 1: ten years to supernova, or this one is ten million

694
00:32:59,480 --> 00:33:02,160
Speaker 1: years to supernova. But all of these things are pretty

695
00:33:02,200 --> 00:33:04,600
Speaker 1: far away. So you don't have to be too worried

696
00:33:04,600 --> 00:33:05,040
Speaker 1: about it.

697
00:33:05,200 --> 00:33:07,479
Speaker 2: Right, they're far away, but it maybe depends on the

698
00:33:07,520 --> 00:33:11,240
Speaker 2: size of the explosion, Like if something is super duper massive,

699
00:33:11,640 --> 00:33:14,160
Speaker 2: could that explosion affect us? Or is the distance going

700
00:33:14,200 --> 00:33:15,040
Speaker 2: to keep us safe?

701
00:33:15,160 --> 00:33:17,920
Speaker 1: So really the danger zone is something like twenty five

702
00:33:18,040 --> 00:33:21,440
Speaker 1: light years. Anything like twenty five light years away or

703
00:33:21,480 --> 00:33:24,520
Speaker 1: closer is going to do some significant damage to the Earth.

704
00:33:24,560 --> 00:33:27,440
Speaker 1: Anything further away than twenty five or fifty light years

705
00:33:27,880 --> 00:33:29,920
Speaker 1: is so far away that things are not going to

706
00:33:29,920 --> 00:33:32,480
Speaker 1: be so dramatic. Remember that all the radiation that comes

707
00:33:32,520 --> 00:33:34,760
Speaker 1: out of a supernova and all the particles and all

708
00:33:34,800 --> 00:33:38,360
Speaker 1: the energy drops very quickly as the distance gets larger,

709
00:33:38,520 --> 00:33:41,760
Speaker 1: because there's this one over distance squared rule in physics.

710
00:33:42,120 --> 00:33:44,640
Speaker 1: So if you are ten times further away, then the

711
00:33:44,840 --> 00:33:48,160
Speaker 1: amount of radiation is one over one hundred, and if

712
00:33:48,160 --> 00:33:51,040
Speaker 1: you're a thousand times further away, then the radiation drops

713
00:33:51,080 --> 00:33:53,400
Speaker 1: by a million. So every time the distance doubles, the

714
00:33:53,480 --> 00:33:55,160
Speaker 1: danger drops by a factor of four.

715
00:33:55,480 --> 00:33:57,800
Speaker 2: All right, so that means we're safe. Right, Like the

716
00:33:57,960 --> 00:34:01,960
Speaker 2: nearest star to us that could even goes supernova is

717
00:34:02,440 --> 00:34:06,320
Speaker 2: two hundred and fifty light years away, so we're good, right, maybe.

718
00:34:06,400 --> 00:34:08,800
Speaker 1: I mean there is this other star called I K. Pagassi.

719
00:34:08,800 --> 00:34:11,600
Speaker 1: It's about one hundred and fifty light years away, and

720
00:34:11,640 --> 00:34:14,040
Speaker 1: it's actually kind of small, but they think it's a

721
00:34:14,080 --> 00:34:17,080
Speaker 1: candidate to be a Type one A supernova because they

722
00:34:17,080 --> 00:34:18,960
Speaker 1: think it's probably gonna end up as a white dwarf,

723
00:34:19,320 --> 00:34:21,920
Speaker 1: and there is a red super giant nearby that it

724
00:34:21,960 --> 00:34:24,640
Speaker 1: could draw. So it's like a candidate to be a

725
00:34:24,680 --> 00:34:27,680
Speaker 1: Type one A supernova. And those are the most dangerous ones, right,

726
00:34:27,719 --> 00:34:29,640
Speaker 1: those are the ten times as bright ones.

727
00:34:29,840 --> 00:34:31,480
Speaker 2: Yeah, that's what I meant earlier. It sort of depends

728
00:34:31,520 --> 00:34:33,640
Speaker 2: on how big the explosion. So is a Type one

729
00:34:33,680 --> 00:34:36,399
Speaker 2: A explosion one hundred and fifty light years away from

730
00:34:36,480 --> 00:34:40,680
Speaker 2: us safe or would that totally burn us to a crisp.

731
00:34:40,480 --> 00:34:42,200
Speaker 1: Well, let's do the math. One hundred and fifty light

732
00:34:42,239 --> 00:34:44,880
Speaker 1: years away, it's like six times as far away as

733
00:34:44,920 --> 00:34:47,560
Speaker 1: the danger zone we said of like twenty five light years,

734
00:34:48,040 --> 00:34:51,160
Speaker 1: and so to be as dangerous at one hundred and

735
00:34:51,200 --> 00:34:53,879
Speaker 1: fifty light years away as another supernova is a twenty

736
00:34:53,880 --> 00:34:56,480
Speaker 1: five light years away. Since it's six times as far,

737
00:34:56,560 --> 00:34:59,160
Speaker 1: it would have to be like thirty six times as powerful,

738
00:35:00,200 --> 00:35:03,160
Speaker 1: only ten times as powerful then we'll be all right.

739
00:35:03,320 --> 00:35:04,800
Speaker 2: Okay, so that's good news.

740
00:35:04,800 --> 00:35:06,320
Speaker 1: Then that is good news.

741
00:35:06,360 --> 00:35:07,600
Speaker 2: Exactly, we're safe.

742
00:35:07,760 --> 00:35:09,960
Speaker 1: We're safe. But you know, a lot of it depends on

743
00:35:10,000 --> 00:35:13,320
Speaker 1: the uncertain physics of supernovas, or we just don't really

744
00:35:13,400 --> 00:35:15,960
Speaker 1: know which stars are going to go supernova or not,

745
00:35:16,239 --> 00:35:17,640
Speaker 1: so we could always be surprised.

746
00:35:17,840 --> 00:35:21,360
Speaker 2: You mean, like if we're totally wrong about this limit

747
00:35:21,480 --> 00:35:23,839
Speaker 2: for star, Like if we're wrong and our star could

748
00:35:23,840 --> 00:35:26,480
Speaker 2: certainly go supernova, is that even a possibilities? I think

749
00:35:26,480 --> 00:35:28,160
Speaker 2: that's what you're saying, right, Like, what if we're wrong,

750
00:35:28,400 --> 00:35:30,799
Speaker 2: what if like any star can go supernova? Or are

751
00:35:30,800 --> 00:35:32,759
Speaker 2: we pretty sure it's not going to go supernova.

752
00:35:32,840 --> 00:35:35,360
Speaker 1: We're pretty sure our star is not going to go supernova.

753
00:35:35,680 --> 00:35:37,880
Speaker 1: I'm just saying, don't take financial advice based on the

754
00:35:37,960 --> 00:35:40,120
Speaker 1: uncertain physics of supernovas.

755
00:35:41,920 --> 00:35:45,759
Speaker 2: Don't take financial advice from physicists in any circumstance that's right,

756
00:35:45,800 --> 00:35:47,360
Speaker 2: super nova or not exactly.

757
00:35:47,400 --> 00:35:49,160
Speaker 1: That's why we have the whole crash in two thousand

758
00:35:49,160 --> 00:35:51,719
Speaker 1: and eight. Too many physicists working on Wall Street.

759
00:35:54,200 --> 00:35:56,680
Speaker 2: Because there were too distracted looking at stars and not

760
00:35:56,760 --> 00:35:58,640
Speaker 2: paying attention to the economy.

761
00:35:59,000 --> 00:36:02,080
Speaker 1: Because they were buildings, numerical models that didn't make any sense.

762
00:36:01,880 --> 00:36:03,839
Speaker 2: Because clearly they don't care about money if they went

763
00:36:03,880 --> 00:36:05,279
Speaker 2: into a career in physics.

764
00:36:07,000 --> 00:36:10,120
Speaker 1: But if there was a supernova nearby, it is interesting

765
00:36:10,160 --> 00:36:13,400
Speaker 1: to think about exactly what the danger is. In one sense,

766
00:36:13,400 --> 00:36:16,040
Speaker 1: we're fortunate because most of the energy of a supernova

767
00:36:16,080 --> 00:36:18,480
Speaker 1: is actually put out in the form of neutrinos, Like

768
00:36:18,640 --> 00:36:22,400
Speaker 1: ninety nine percent of the crazy energy of a supernova

769
00:36:22,480 --> 00:36:24,840
Speaker 1: comes out in the form of neutrinos, which the universe

770
00:36:24,880 --> 00:36:28,239
Speaker 1: is mostly transparent to, so it's not actually dangerous. A

771
00:36:28,400 --> 00:36:31,160
Speaker 1: huge flux of neutrinos could pass right through you. You wouldn't

772
00:36:31,160 --> 00:36:33,399
Speaker 1: even notice it's happening. Right now, the Sun puts out

773
00:36:33,400 --> 00:36:36,359
Speaker 1: lots of neutrinos, you don't even notice. So it's like

774
00:36:36,440 --> 00:36:38,480
Speaker 1: that one percent of the energy of the supernova which

775
00:36:38,480 --> 00:36:42,280
Speaker 1: comes at as like very high energy photons gamma rays,

776
00:36:42,680 --> 00:36:44,200
Speaker 1: that could potentially damage us.

777
00:36:44,719 --> 00:36:45,760
Speaker 2: So it would be bad news.

778
00:36:45,920 --> 00:36:48,480
Speaker 1: It would be bad news. Like if it's high enough

779
00:36:48,520 --> 00:36:50,960
Speaker 1: intensity that actually makes it down to the surface, that

780
00:36:51,040 --> 00:36:53,799
Speaker 1: gets through the ozone layer in our atmosphere, which is

781
00:36:53,840 --> 00:36:56,480
Speaker 1: mostly opaque to these very high energy photons, then they

782
00:36:56,480 --> 00:36:58,879
Speaker 1: would just directly fry you, right, and it would fry

783
00:36:58,880 --> 00:37:02,799
Speaker 1: the Earth. The supernovas they are very short lived, but

784
00:37:02,880 --> 00:37:06,080
Speaker 1: you know we're talking about like days, weeks, months, So

785
00:37:06,280 --> 00:37:08,120
Speaker 1: even if you're on the other side of the Earth,

786
00:37:08,280 --> 00:37:10,319
Speaker 1: eventually the Earth is going to rotate and you're going

787
00:37:10,400 --> 00:37:14,400
Speaker 1: to be exposed. So unless the supernova is super short lived,

788
00:37:14,560 --> 00:37:17,280
Speaker 1: it's gonna fry both sides of the Earth. That's pretty unlikely.

789
00:37:17,320 --> 00:37:19,720
Speaker 1: It'd have to be super close to like literally actually

790
00:37:19,719 --> 00:37:22,759
Speaker 1: fry the Earth to a crisp More realistic is if

791
00:37:22,760 --> 00:37:24,920
Speaker 1: the supernova's close enough to o bathe us in high

792
00:37:24,960 --> 00:37:28,480
Speaker 1: energy radiation, but the atmosphere absorbs that. Even that would

793
00:37:28,520 --> 00:37:31,520
Speaker 1: be pretty dangerous because they would basically deplete our ozone layer.

794
00:37:31,560 --> 00:37:34,320
Speaker 1: It would fry all the oxygen and nitrogen the atmosphere

795
00:37:34,360 --> 00:37:38,680
Speaker 1: into other oxides and basically strip us up protection, exposing

796
00:37:38,760 --> 00:37:41,720
Speaker 1: us to UV radiation from the Sun, which would basically

797
00:37:42,160 --> 00:37:45,040
Speaker 1: kill all the planks in the oceans, which would undermine

798
00:37:45,040 --> 00:37:47,800
Speaker 1: the ecosystem, and things would be bad.

799
00:37:48,000 --> 00:37:48,920
Speaker 2: Things would be bad.

800
00:37:49,080 --> 00:37:50,040
Speaker 1: Things would be bad.

801
00:37:50,120 --> 00:37:52,840
Speaker 2: Well, I think that answer is Christo's question directly, Like

802
00:37:52,880 --> 00:37:55,600
Speaker 2: he asked, what would happen if there's a supernova nearby?

803
00:37:55,760 --> 00:37:58,160
Speaker 2: And the answer is bad. Things would happen, we would

804
00:37:58,200 --> 00:38:01,839
Speaker 2: get fried or ozone would get fried. It would be

805
00:38:02,400 --> 00:38:05,480
Speaker 2: not good. But the bigger answer is that it's not

806
00:38:05,760 --> 00:38:08,239
Speaker 2: likely to happen. Like, as far as we know, there

807
00:38:08,280 --> 00:38:12,200
Speaker 2: are no stars nearras enough that might go supernova to

808
00:38:12,280 --> 00:38:12,880
Speaker 2: really harm us.

809
00:38:13,000 --> 00:38:15,280
Speaker 1: That's right. So for the near future we're pretty safe.

810
00:38:15,560 --> 00:38:18,560
Speaker 1: Remember that the stars were nearby change as the galaxy

811
00:38:18,640 --> 00:38:20,560
Speaker 1: is rotating and we move up and down through the

812
00:38:20,600 --> 00:38:22,799
Speaker 1: galactic disk, And so this is sort of like an

813
00:38:22,840 --> 00:38:25,600
Speaker 1: answer for right now or the next few thousand years.

814
00:38:25,960 --> 00:38:28,400
Speaker 1: You want to project forward to like hundreds of millions

815
00:38:28,400 --> 00:38:31,399
Speaker 1: of years, then things might change and other stars might

816
00:38:31,440 --> 00:38:34,440
Speaker 1: get closer to us that are more dangerous. They estimate

817
00:38:34,480 --> 00:38:37,600
Speaker 1: when they look back that maybe twenty supernovas have happened

818
00:38:37,600 --> 00:38:39,880
Speaker 1: within a thousand light years of Earth in the last

819
00:38:39,920 --> 00:38:42,680
Speaker 1: ten million years. But remember a thousand light years is

820
00:38:42,719 --> 00:38:45,560
Speaker 1: pretty far away. That's well out of the danger zone.

821
00:38:46,080 --> 00:38:49,240
Speaker 2: But don't we sort of know, like all the stars

822
00:38:49,360 --> 00:38:51,319
Speaker 2: our neighborhood, like how it's going to change over the

823
00:38:51,360 --> 00:38:53,920
Speaker 2: next you know, maybe several hundred million years. Can we

824
00:38:54,280 --> 00:38:54,880
Speaker 2: do that math?

825
00:38:55,040 --> 00:38:57,320
Speaker 1: We can do that math in some cases, but measuring

826
00:38:57,360 --> 00:39:00,400
Speaker 1: these stellar velocities can be challenging. We have these awesome

827
00:39:00,400 --> 00:39:03,360
Speaker 1: new satellites, a Gaya satellite, for example, which is cataloging

828
00:39:03,520 --> 00:39:06,400
Speaker 1: the exact location of these stars and tracking them, and

829
00:39:06,400 --> 00:39:08,720
Speaker 1: so we're getting better and better at modeling these things.

830
00:39:08,960 --> 00:39:11,680
Speaker 1: But it's kind of chaotic, right, stars pull and tug

831
00:39:11,719 --> 00:39:14,320
Speaker 1: on each other. You have a very high number of objects.

832
00:39:14,520 --> 00:39:17,040
Speaker 1: We can't really even solve equations for three objects, and

833
00:39:17,160 --> 00:39:20,200
Speaker 1: we're talking about like one hundreds or thousands or millions

834
00:39:20,239 --> 00:39:23,480
Speaker 1: of objects, So there can be chaotic predictions. You can

835
00:39:23,520 --> 00:39:26,000
Speaker 1: never really be sure what's going to happen deep into

836
00:39:26,040 --> 00:39:26,480
Speaker 1: the future.

837
00:39:27,280 --> 00:39:30,400
Speaker 2: All right, So Christoph, the answer is bad things might happen,

838
00:39:30,480 --> 00:39:33,040
Speaker 2: but you don't have to worry about that, but maybe

839
00:39:33,120 --> 00:39:35,319
Speaker 2: check back again in one hundred million years, just to

840
00:39:35,440 --> 00:39:35,960
Speaker 2: double check.

841
00:39:36,680 --> 00:39:38,880
Speaker 1: Keep making those retirement deposits.

842
00:39:38,440 --> 00:39:41,000
Speaker 2: Though, I think he's good for now. All right, Well,

843
00:39:41,040 --> 00:39:43,120
Speaker 2: let's get to our last question of the day, and

844
00:39:43,200 --> 00:39:47,839
Speaker 2: this one is about storms in our solar system. We'll

845
00:39:47,840 --> 00:39:50,280
Speaker 2: get into that, but first let's take another quick break.

846
00:40:02,800 --> 00:40:06,920
Speaker 2: All right. We're answering listener questions here today about the

847
00:40:06,960 --> 00:40:10,560
Speaker 2: ways that the universe could put an end to human

848
00:40:10,600 --> 00:40:14,600
Speaker 2: existence perhaps, and so our last question comes from Jane

849
00:40:14,680 --> 00:40:16,400
Speaker 2: who is in fifth grade.

850
00:40:16,800 --> 00:40:18,080
Speaker 3: Hi, I'm Jane.

851
00:40:18,440 --> 00:40:21,680
Speaker 2: I'm in fifth grade and we're learning about our solar system,

852
00:40:22,000 --> 00:40:25,200
Speaker 2: and I would like to know what is the strongest

853
00:40:25,239 --> 00:40:28,799
Speaker 2: storm in our solar system. Awesome question from Jane. Thank

854
00:40:28,840 --> 00:40:31,040
Speaker 2: you Jane for asking that question. I wonder if she's

855
00:40:31,160 --> 00:40:34,360
Speaker 2: asking so whether she knows to bring an umbrella to

856
00:40:34,400 --> 00:40:35,400
Speaker 2: school the next day.

857
00:40:36,320 --> 00:40:38,319
Speaker 1: Or maybe she's planning a trip and she wants to

858
00:40:38,360 --> 00:40:42,880
Speaker 1: know if she should visit Venus or Mars or Jupiter because.

859
00:40:42,600 --> 00:40:45,160
Speaker 2: She wants to see the storm or avoid the storm.

860
00:40:45,239 --> 00:40:46,800
Speaker 2: She sounds like a very curious person.

861
00:40:46,960 --> 00:40:49,799
Speaker 1: She does sound like it. Yeah, exactly, Let's send Jane

862
00:40:49,840 --> 00:40:51,440
Speaker 1: on our next trip to visit the Sun.

863
00:40:52,160 --> 00:40:55,359
Speaker 2: Give her a lead umbrella just in case. I guess

864
00:40:55,360 --> 00:40:58,600
Speaker 2: her question is that like actual storms, like weather storms

865
00:40:58,600 --> 00:41:01,799
Speaker 2: that happen not just on Earth, they happen in other planets, right,

866
00:41:01,920 --> 00:41:05,000
Speaker 2: other planets half atmospheres with gases and things like that,

867
00:41:05,080 --> 00:41:08,919
Speaker 2: and clouds and weather. And so her question, I think

868
00:41:09,080 --> 00:41:11,400
Speaker 2: is like, out of all the planets in the Solar System,

869
00:41:11,760 --> 00:41:13,759
Speaker 2: who has the biggest storm that we've seen?

870
00:41:13,880 --> 00:41:16,879
Speaker 1: Yeah, because there's this tendency to imagine that things out

871
00:41:16,920 --> 00:41:18,600
Speaker 1: there in the universe are sort of like they are

872
00:41:18,680 --> 00:41:21,480
Speaker 1: here on Earth. But as you look around the Solar System,

873
00:41:21,480 --> 00:41:24,000
Speaker 1: you discover, wow, Earth is pretty different, right. We have

874
00:41:24,320 --> 00:41:27,040
Speaker 1: liquid water on the surface, we have clouds, we have

875
00:41:27,200 --> 00:41:29,440
Speaker 1: very different kind of situation. And the storms we have

876
00:41:29,520 --> 00:41:32,120
Speaker 1: here on Earth are actually not very representative of what's

877
00:41:32,160 --> 00:41:34,400
Speaker 1: going on in the rest of the Solar System. It's

878
00:41:34,440 --> 00:41:38,080
Speaker 1: actually quite nice and calm here on Earth compared to

879
00:41:38,200 --> 00:41:40,160
Speaker 1: the stormy Solar system we live in.

880
00:41:40,360 --> 00:41:42,360
Speaker 2: Yeah, so that's the recap of all the storms in

881
00:41:42,360 --> 00:41:45,000
Speaker 2: the Solar system, starting with I guess the Sun, right,

882
00:41:45,000 --> 00:41:45,960
Speaker 2: the Sun has storms.

883
00:41:46,200 --> 00:41:49,759
Speaker 1: The Sun has really big storms. Right. It's not just

884
00:41:49,880 --> 00:41:53,680
Speaker 1: a ball of plasma. It's like throbbing and pulsating, and

885
00:41:53,719 --> 00:41:56,560
Speaker 1: there's these tubes of plasma controlled by magnetic fields that

886
00:41:56,560 --> 00:41:59,920
Speaker 1: we don't even really understand. And occasionally big loops of

887
00:42:00,040 --> 00:42:04,080
Speaker 1: plasma are ejected from the Sun and travel towards the Earth.

888
00:42:04,400 --> 00:42:07,240
Speaker 1: These are called coronal mass ejections, and when they happen,

889
00:42:07,320 --> 00:42:10,440
Speaker 1: they're very dramatic, like these loops of plasma can be

890
00:42:10,560 --> 00:42:13,799
Speaker 1: bigger than the entire Earth. And so some of the

891
00:42:13,800 --> 00:42:17,160
Speaker 1: biggest storms in the Solar System are in the Sun itself.

892
00:42:18,239 --> 00:42:20,719
Speaker 2: I guess maybe let's take a quick step back here,

893
00:42:20,760 --> 00:42:23,080
Speaker 2: and what do you define as a storm, Like what

894
00:42:23,160 --> 00:42:25,320
Speaker 2: counts as a storm and what is just the irregular

895
00:42:25,360 --> 00:42:26,200
Speaker 2: things moving around.

896
00:42:26,320 --> 00:42:28,200
Speaker 1: Yeah, it's a good question. I guess I would call

897
00:42:28,280 --> 00:42:32,040
Speaker 1: a storm sort of an unusual high energy like high

898
00:42:32,080 --> 00:42:35,319
Speaker 1: speed or high velocity event, right, Like, that's what we

899
00:42:35,320 --> 00:42:37,840
Speaker 1: think about on Earth. There's wind every day, there's a

900
00:42:37,880 --> 00:42:40,400
Speaker 1: storm when the wind is sort of like unusually high,

901
00:42:40,440 --> 00:42:42,239
Speaker 1: or there's unusual amount of rain.

902
00:42:43,120 --> 00:42:46,160
Speaker 2: Okay, so like when things get exciting in the atmosphere

903
00:42:46,239 --> 00:42:46,880
Speaker 2: or something.

904
00:42:47,000 --> 00:42:50,960
Speaker 1: Exactly exciting or dangerous depending on your attitude. And so

905
00:42:51,000 --> 00:42:54,880
Speaker 1: basically we're thinking about like unusual events like tales of distributions.

906
00:42:55,320 --> 00:42:57,400
Speaker 1: And it's even fun to think about like the strongest

907
00:42:57,400 --> 00:43:01,160
Speaker 1: storms here on Earth. The strongest typhoon on Earth or

908
00:43:01,280 --> 00:43:04,400
Speaker 1: equivalently hurricane depending on which ocean you're in, was in

909
00:43:04,480 --> 00:43:08,879
Speaker 1: nineteen and seventy nine. It's called Typhoon Tip and this

910
00:43:09,000 --> 00:43:12,960
Speaker 1: lasted for weeks, and it was one thousand miles wide.

911
00:43:13,640 --> 00:43:16,120
Speaker 1: It's like big enough to cover like half of the

912
00:43:16,239 --> 00:43:19,080
Speaker 1: United States, though he was actually in the Pacific.

913
00:43:20,080 --> 00:43:22,160
Speaker 2: So this is a weather event here on Earth that

914
00:43:22,360 --> 00:43:25,239
Speaker 2: was one thousand miles wide. And here on Earth, I

915
00:43:25,239 --> 00:43:28,880
Speaker 2: guess storms happened because you know, there's air currents moving around,

916
00:43:28,920 --> 00:43:31,320
Speaker 2: because the air heats up from the sun and moves

917
00:43:31,360 --> 00:43:34,680
Speaker 2: into the cold sides. And I guess sometimes in all

918
00:43:34,760 --> 00:43:37,759
Speaker 2: of this air moving, sometimes you get like these pockets

919
00:43:37,800 --> 00:43:40,319
Speaker 2: of things where things get intense. That's kind of what

920
00:43:40,360 --> 00:43:41,759
Speaker 2: a storm is on Earth.

921
00:43:41,560 --> 00:43:44,480
Speaker 1: Exactly, and they get spinning because of the Coriolis force,

922
00:43:44,480 --> 00:43:47,160
Speaker 1: which is why these storms spin differently in the Northern

923
00:43:47,239 --> 00:43:50,040
Speaker 1: Hemisphere and the Southern hemisphere. You know, it's a myth

924
00:43:50,200 --> 00:43:53,560
Speaker 1: that toilets flush differently in Australia than they do in

925
00:43:53,600 --> 00:43:56,000
Speaker 1: the US, for example, But it's not a myth that

926
00:43:56,120 --> 00:43:58,920
Speaker 1: storms spin differently in the northern and southern hemispheres.

927
00:43:59,000 --> 00:44:00,920
Speaker 2: How do you know it's a myth? You have you

928
00:44:00,960 --> 00:44:03,760
Speaker 2: flushed every toilet in Australia to make that statement.

929
00:44:05,040 --> 00:44:07,400
Speaker 1: I have not gone on a toilet flushing tour of Australia.

930
00:44:07,440 --> 00:44:09,360
Speaker 1: That's still on my to do list. But I've relied

931
00:44:09,400 --> 00:44:12,120
Speaker 1: on listeners who've written in who can verify this for us.

932
00:44:12,160 --> 00:44:14,160
Speaker 2: But it is true that it affects like if you

933
00:44:14,280 --> 00:44:16,760
Speaker 2: drain a giant waiting pool, it is going to affect

934
00:44:16,760 --> 00:44:21,680
Speaker 2: how the water swirls. Right, maybe, just like in toilets

935
00:44:21,719 --> 00:44:22,280
Speaker 2: is too small.

936
00:44:23,080 --> 00:44:25,279
Speaker 1: If you have a hurricane sized toilet, then yes, that

937
00:44:25,320 --> 00:44:27,960
Speaker 1: will definitely affect you. I'm not exactly sure what the

938
00:44:28,040 --> 00:44:31,040
Speaker 1: minimum sized toilet has to be to see this effect.

939
00:44:31,200 --> 00:44:33,120
Speaker 2: Sounds like an experiment of physicist should do.

940
00:44:33,360 --> 00:44:35,239
Speaker 1: I'm going to go ride a grand proposal after we're

941
00:44:35,239 --> 00:44:35,959
Speaker 1: done here, all.

942
00:44:35,920 --> 00:44:38,200
Speaker 2: Right, So then on Earth, that's the biggest storm and

943
00:44:38,280 --> 00:44:41,440
Speaker 2: in recorded history, one thousand miles wide a couple of

944
00:44:41,480 --> 00:44:42,200
Speaker 2: decades ago.

945
00:44:42,920 --> 00:44:45,080
Speaker 1: Lasted for weeks and had winds up to like six

946
00:44:45,200 --> 00:44:47,839
Speaker 1: hundred kilometers per hour, which is pretty dramatic. And then

947
00:44:47,920 --> 00:44:51,000
Speaker 1: of course there are storms on our neighboring planets. Venus

948
00:44:51,080 --> 00:44:53,759
Speaker 1: has storms, and in general the weather on Venus is

949
00:44:53,840 --> 00:44:57,919
Speaker 1: generally pretty terrible. It's like very high air pressure, very

950
00:44:57,920 --> 00:45:04,200
Speaker 1: strong winds, sulfuric acid rain, lightning storms driven by volcanic eruptions.

951
00:45:03,840 --> 00:45:06,000
Speaker 2: And it's super hot in Venus too, right, And it's.

952
00:45:05,840 --> 00:45:08,680
Speaker 1: Super hot exactly, is the reason that when we talk

953
00:45:08,719 --> 00:45:12,280
Speaker 1: about colonizing Venus, we think about like creating floating cities

954
00:45:12,320 --> 00:45:14,959
Speaker 1: above the cloud layers. But there are also some really

955
00:45:15,000 --> 00:45:18,960
Speaker 1: cool storms on Venus at its poles, like the pioneer

956
00:45:19,080 --> 00:45:23,319
Speaker 1: Venus spacecraft in nineteen seventy nine saw this really incredible

957
00:45:23,400 --> 00:45:27,480
Speaker 1: hurricane on Venus's north pole that had two eyes to it.

958
00:45:28,000 --> 00:45:31,480
Speaker 1: The storms on Earth usually have one core, right, there's

959
00:45:31,480 --> 00:45:33,400
Speaker 1: an eye at the center and it's a big swirl,

960
00:45:33,520 --> 00:45:35,919
Speaker 1: but this one on the north pole of Venus has

961
00:45:36,000 --> 00:45:37,680
Speaker 1: two eyes. Whoa.

962
00:45:38,040 --> 00:45:40,160
Speaker 2: It sounds like somebody flushed two toilets at the same

963
00:45:40,239 --> 00:45:42,320
Speaker 2: time in the north pole of Venus.

964
00:45:42,400 --> 00:45:44,280
Speaker 1: And then they went back to Venus in two thousand

965
00:45:44,320 --> 00:45:47,440
Speaker 1: and six and the Venus Express saw what looked like

966
00:45:47,560 --> 00:45:50,440
Speaker 1: a double vortex at the south pole. As a scientist

967
00:45:50,640 --> 00:45:54,960
Speaker 1: where like, whoa, maybe these crazy double hurricanes on Venus

968
00:45:55,000 --> 00:45:57,719
Speaker 1: are stable and permanent, But as they watched, they saw

969
00:45:57,719 --> 00:46:00,920
Speaker 1: that it sort of shifted and morphed and didn't really survive.

970
00:46:01,120 --> 00:46:05,040
Speaker 2: It didn't become a viral video. This is going WHOA

971
00:46:05,320 --> 00:46:06,680
Speaker 2: double storm.

972
00:46:07,880 --> 00:46:10,680
Speaker 1: But it's interesting because Venus has these like very high

973
00:46:10,719 --> 00:46:13,600
Speaker 1: wind speeds, and the weather changes a lot from the

974
00:46:13,719 --> 00:46:17,080
Speaker 1: poles to the equator, where the winds, for example, vary

975
00:46:17,120 --> 00:46:19,480
Speaker 1: greatly with altitude. The windspeeds can vary by like a

976
00:46:19,520 --> 00:46:22,880
Speaker 1: factor of two. Anyway, it's really crazy weather on Venus,

977
00:46:22,880 --> 00:46:23,600
Speaker 1: as well, all.

978
00:46:23,560 --> 00:46:25,640
Speaker 2: Right, well, what's there in the next planet on the

979
00:46:25,680 --> 00:46:28,120
Speaker 2: list of Mars. Does Mars get storms?

980
00:46:28,239 --> 00:46:29,600
Speaker 1: Mars does get storms.

981
00:46:29,719 --> 00:46:32,359
Speaker 2: Mars has a very sparse atmosphere, right, yeah, and so.

982
00:46:32,360 --> 00:46:35,719
Speaker 1: They can look very dramatic, but they're not actually that powerful.

983
00:46:36,200 --> 00:46:39,480
Speaker 1: Like there are maybe once per decade or so a

984
00:46:39,640 --> 00:46:42,960
Speaker 1: dust storm that can engulf like the entire planet for

985
00:46:43,000 --> 00:46:46,200
Speaker 1: a whole month. That's pretty dramatic. And people who saw

986
00:46:46,239 --> 00:46:48,600
Speaker 1: the movie The Martian will have noticed like, ooh wow,

987
00:46:48,640 --> 00:46:51,080
Speaker 1: these storms are dangerous and they can knock stuff over.

988
00:46:51,480 --> 00:46:53,480
Speaker 1: But as you say, Mars does not have a very

989
00:46:53,520 --> 00:46:56,200
Speaker 1: dense atmosphere. It's like one percent as dense as the

990
00:46:56,239 --> 00:46:59,279
Speaker 1: Earth's atmosphere, and so like you couldn't really fly a

991
00:46:59,360 --> 00:47:03,040
Speaker 1: kite on very easily. Or the helicopter that they recently

992
00:47:03,120 --> 00:47:05,680
Speaker 1: landed on Mars was really amazing that he could even

993
00:47:05,719 --> 00:47:08,920
Speaker 1: fly because the air is so sparse, So even the

994
00:47:08,960 --> 00:47:12,120
Speaker 1: wind in like the largest dust storm on Mars could

995
00:47:12,120 --> 00:47:15,800
Speaker 1: not really tip over or rip apart like major mechanical equipment,

996
00:47:16,000 --> 00:47:17,520
Speaker 1: not the way storms here on Earth do.

997
00:47:17,800 --> 00:47:21,000
Speaker 2: But isn't it the case that scientists think Mars had

998
00:47:21,000 --> 00:47:23,280
Speaker 2: an atmosphere and past or maybe Mars did have bigger

999
00:47:23,280 --> 00:47:24,280
Speaker 2: storms before.

1000
00:47:24,400 --> 00:47:27,440
Speaker 1: Yeah, Mars probably lost its atmosphere because of solar winds

1001
00:47:27,480 --> 00:47:29,919
Speaker 1: and the lack of a magnetic field. And also it's

1002
00:47:29,960 --> 00:47:31,880
Speaker 1: just lower mass and so it's not as good as

1003
00:47:31,920 --> 00:47:34,839
Speaker 1: holding onto its particles. So in its past it may

1004
00:47:34,880 --> 00:47:38,240
Speaker 1: have had more dramatic storms. These days, they look dramatic,

1005
00:47:38,280 --> 00:47:39,880
Speaker 1: but they're not actually very intense.

1006
00:47:40,200 --> 00:47:42,440
Speaker 2: All right, let's get to some of the bigger planets.

1007
00:47:42,560 --> 00:47:43,360
Speaker 2: What about Jupiter.

1008
00:47:43,600 --> 00:47:46,879
Speaker 1: Jupiter has, of course the famous Great Red Spot. This

1009
00:47:46,920 --> 00:47:49,600
Speaker 1: is a huge storm, a few times the size of

1010
00:47:49,640 --> 00:47:52,799
Speaker 1: the Earth, right, so, like we're talking mind boggling all

1011
00:47:52,920 --> 00:47:55,960
Speaker 1: sizes here, though again it's small compared to Jupiter, which

1012
00:47:56,000 --> 00:47:58,279
Speaker 1: is just much much bigger than the Earth. The Great

1013
00:47:58,280 --> 00:48:01,799
Speaker 1: Red Spot goes around Jupiter six earth days and it's

1014
00:48:01,800 --> 00:48:05,160
Speaker 1: like a couple hundred miles deep, and it's really impressive

1015
00:48:05,160 --> 00:48:07,920
Speaker 1: because it's lasted a long time. Like we've been watching

1016
00:48:07,920 --> 00:48:12,240
Speaker 1: this storm on Jupiter since Galileo, basically since the sixteen hundreds,

1017
00:48:12,760 --> 00:48:15,279
Speaker 1: and so it's hundreds of years old, which makes it

1018
00:48:15,360 --> 00:48:16,400
Speaker 1: incredibly stable.

1019
00:48:16,920 --> 00:48:20,799
Speaker 2: Mmm. Yeah, and it's shrinking too, right, like it's been

1020
00:48:20,840 --> 00:48:21,560
Speaker 2: getting smaller.

1021
00:48:21,719 --> 00:48:23,800
Speaker 1: Yeah, it is stable in that it's like lasted a

1022
00:48:23,840 --> 00:48:26,200
Speaker 1: long time, but in the last forty years or so,

1023
00:48:26,280 --> 00:48:29,319
Speaker 1: we noticed that it has been getting smaller. Now it's

1024
00:48:29,360 --> 00:48:31,880
Speaker 1: like maybe just one and a half times the size

1025
00:48:31,880 --> 00:48:34,600
Speaker 1: of the Earth. And you know, not something we understand

1026
00:48:34,680 --> 00:48:37,920
Speaker 1: very well. These chaotic things turbulence and vortices are very

1027
00:48:37,960 --> 00:48:40,879
Speaker 1: difficult to model and very difficult to understand. But it's

1028
00:48:40,920 --> 00:48:42,200
Speaker 1: still a huge.

1029
00:48:41,880 --> 00:48:44,279
Speaker 2: Storm, right, and we don't know why it's red, right,

1030
00:48:45,040 --> 00:48:46,000
Speaker 2: Like we don't know for sure.

1031
00:48:46,120 --> 00:48:48,359
Speaker 1: Yeah, that's right, And we did a whole episode about

1032
00:48:48,400 --> 00:48:50,400
Speaker 1: the Great Red Spots to dig into that. If you

1033
00:48:50,480 --> 00:48:54,000
Speaker 1: want to learn more about that crazy storm.

1034
00:48:52,960 --> 00:48:55,400
Speaker 2: M all right, how about Saturn.

1035
00:48:55,719 --> 00:48:59,280
Speaker 1: Saturn is super cool because it has really weird storms

1036
00:48:59,320 --> 00:49:02,840
Speaker 1: on the pole like Venus does, remember with its double hurricane,

1037
00:49:02,880 --> 00:49:07,400
Speaker 1: except Saturn has this six sided storm on its poles.

1038
00:49:07,400 --> 00:49:10,880
Speaker 1: It's a hexagon. It's like thirty thousand kilometers widen, like

1039
00:49:10,880 --> 00:49:14,839
Speaker 1: one hundred kilometers deep, first discovered nineteen eighty one by

1040
00:49:14,960 --> 00:49:18,320
Speaker 1: Voyager and then when Cassini flew by took really beautiful

1041
00:49:18,320 --> 00:49:20,839
Speaker 1: pictures of it, and now they think it's probably like

1042
00:49:21,000 --> 00:49:24,800
Speaker 1: a complex set of vortices and different layers of clouds,

1043
00:49:24,800 --> 00:49:28,840
Speaker 1: but it creates this incredible hexagon effect, which looks really weird.

1044
00:49:28,880 --> 00:49:30,280
Speaker 2: It's almost like it's wearing a hat.

1045
00:49:30,640 --> 00:49:33,600
Speaker 1: Yeah, exactly, all right, yeah, i'mu coo right, yeah, But

1046
00:49:33,640 --> 00:49:36,480
Speaker 1: it's sort of a stable feature of Saturn, we think.

1047
00:49:36,760 --> 00:49:40,120
Speaker 1: On the other hand, Saturn also has unusual features, like

1048
00:49:40,160 --> 00:49:42,680
Speaker 1: it has these storms which crop up like every twenty

1049
00:49:42,800 --> 00:49:46,839
Speaker 1: or thirty years, and sometimes they can encircle the entire planet.

1050
00:49:47,120 --> 00:49:49,480
Speaker 1: So there was one in December of twenty ten that

1051
00:49:49,600 --> 00:49:52,719
Speaker 1: was like ten times the size of the Earth, so

1052
00:49:52,840 --> 00:49:55,640
Speaker 1: like much bigger than even the Great Red Spot and

1053
00:49:55,719 --> 00:49:57,000
Speaker 1: lasted for like ten months.

1054
00:49:57,239 --> 00:50:00,279
Speaker 2: Whoa, it's a big store. And how fast we're the

1055
00:50:00,320 --> 00:50:00,799
Speaker 2: winds moving.

1056
00:50:01,000 --> 00:50:02,600
Speaker 1: The winds in that storm we think move around one

1057
00:50:02,719 --> 00:50:06,799
Speaker 1: hundred kilometers per hour, So pretty dramatic stuff, right. What

1058
00:50:06,880 --> 00:50:10,200
Speaker 1: about Neptune, Well, the strongest winds in the Solar System

1059
00:50:10,440 --> 00:50:13,719
Speaker 1: might be on Neptune, so maybe the biggest storm it

1060
00:50:13,800 --> 00:50:16,160
Speaker 1: was that one on Saturn, but the most powerful winds

1061
00:50:16,160 --> 00:50:19,279
Speaker 1: are probably on Neptune. So in Neptune, we saw this

1062
00:50:19,480 --> 00:50:23,680
Speaker 1: great dark spot in nineteen eighty nine, this huge spot

1063
00:50:23,800 --> 00:50:27,120
Speaker 1: on Neptune, which they now think are methane ice clouds

1064
00:50:27,280 --> 00:50:30,439
Speaker 1: which are forming crystals probably about the size of one

1065
00:50:30,520 --> 00:50:34,080
Speaker 1: Earth this storm had wind speeds of two thousand kilometers

1066
00:50:34,120 --> 00:50:34,600
Speaker 1: per hour.

1067
00:50:34,880 --> 00:50:40,200
Speaker 2: Two thousand kilometers per hour. That's super fast. Is that

1068
00:50:40,320 --> 00:50:42,680
Speaker 2: faster than the speed of sound here on Earth?

1069
00:50:42,800 --> 00:50:44,960
Speaker 1: Yeah? The speed of sound here on Earth is about

1070
00:50:45,239 --> 00:50:47,040
Speaker 1: twelve hundred kilometers per hour.

1071
00:50:47,320 --> 00:50:52,160
Speaker 2: Whoa, So this was a supersonic storm.

1072
00:50:52,600 --> 00:50:55,279
Speaker 1: That's pretty awesome. Although the speed of sound depends a

1073
00:50:55,280 --> 00:50:57,560
Speaker 1: lot on the density and the temperature and all sorts

1074
00:50:57,560 --> 00:50:59,200
Speaker 1: of stuff, So I don't know what the speed of

1075
00:50:59,239 --> 00:51:02,680
Speaker 1: sound is in those methane ice clouds, but yeah, it's

1076
00:51:02,760 --> 00:51:05,880
Speaker 1: faster than the speed of sound in air on Earth.

1077
00:51:06,239 --> 00:51:07,400
Speaker 1: So that's pretty incredible.

1078
00:51:07,480 --> 00:51:09,680
Speaker 2: And it's also the most powerful storm because it's made

1079
00:51:09,719 --> 00:51:12,080
Speaker 2: out of methane, which means it smells like farts.

1080
00:51:14,719 --> 00:51:16,480
Speaker 1: And that's why we're glad it's on Neptune and not

1081
00:51:16,520 --> 00:51:17,320
Speaker 1: on Urinous.

1082
00:51:19,800 --> 00:51:22,440
Speaker 2: He who storm smelt it? I guess.

1083
00:51:24,160 --> 00:51:26,440
Speaker 1: I'm just glad there are no supersonic farts here on Earth.

1084
00:51:26,840 --> 00:51:31,880
Speaker 2: Yeah, or supersonic storms or farts that'd be even worse.

1085
00:51:32,600 --> 00:51:35,479
Speaker 2: All right. So maybe to answer Jamee's question, those would

1086
00:51:35,480 --> 00:51:37,719
Speaker 2: be maybe the candidates we would put up as the

1087
00:51:37,760 --> 00:51:40,279
Speaker 2: strongest storms in our solar system. There's the one at

1088
00:51:40,280 --> 00:51:42,600
Speaker 2: the top of Saturn which looks like a hexagon, which

1089
00:51:42,640 --> 00:51:46,560
Speaker 2: is thirty thousand kilometers wide, which is like ten times

1090
00:51:46,600 --> 00:51:48,560
Speaker 2: the diameter of Earth or something like that.

1091
00:51:48,680 --> 00:51:49,080
Speaker 1: Mm hmm.

1092
00:51:49,400 --> 00:51:52,760
Speaker 2: And then there's the storm we saw on Neptune about

1093
00:51:52,760 --> 00:51:56,680
Speaker 2: thirty years ago that had two thousand kilometers per hour winds.

1094
00:51:56,800 --> 00:51:58,360
Speaker 1: I don't know if you want to study those or

1095
00:51:58,400 --> 00:52:01,320
Speaker 1: avoid those, but either way, some boots in a raincoat.

1096
00:52:01,960 --> 00:52:03,640
Speaker 2: But I guess the Neptune one is gone now.

1097
00:52:03,719 --> 00:52:05,920
Speaker 1: Right when we looked at it again in nineteen ninety

1098
00:52:05,920 --> 00:52:08,000
Speaker 1: four with Hubble, they didn't see it and it has

1099
00:52:08,080 --> 00:52:08,759
Speaker 1: not come back.

1100
00:52:09,080 --> 00:52:11,800
Speaker 2: So maybe the most awesome storm right now is Saturn

1101
00:52:11,880 --> 00:52:14,640
Speaker 2: until we see something else which can happen. Because all

1102
00:52:14,680 --> 00:52:16,719
Speaker 2: of these things are happening right now and they can

1103
00:52:16,800 --> 00:52:17,920
Speaker 2: change at any moment.

1104
00:52:17,800 --> 00:52:20,200
Speaker 1: That's right, And these aren't complex effects. Remember, we can't

1105
00:52:20,280 --> 00:52:23,279
Speaker 1: even predict the weather on Earth very well, and so

1106
00:52:23,360 --> 00:52:25,600
Speaker 1: when it comes to the weather on Neptune, we are

1107
00:52:25,640 --> 00:52:26,520
Speaker 1: all left guessing.

1108
00:52:26,719 --> 00:52:28,600
Speaker 2: All right, Well, thank you Jane for your question. I

1109
00:52:28,600 --> 00:52:31,560
Speaker 2: guess she's maybe asking because, like if we go to

1110
00:52:31,560 --> 00:52:34,560
Speaker 2: another planet, we want to avoid these storms, right because

1111
00:52:34,560 --> 00:52:36,080
Speaker 2: they can also end.

1112
00:52:35,960 --> 00:52:39,000
Speaker 1: Us exactly, Or maybe she's just in awe of the

1113
00:52:39,080 --> 00:52:41,600
Speaker 1: incredible conditions out there in the rest of the Solar System,

1114
00:52:41,719 --> 00:52:44,719
Speaker 1: and grateful that we don't have such crazy storms here and.

1115
00:52:44,680 --> 00:52:47,160
Speaker 2: That we can look at them from a distance. All right, Well,

1116
00:52:47,200 --> 00:52:49,400
Speaker 2: that's all of our questions for today. Thank you to

1117
00:52:49,480 --> 00:52:53,480
Speaker 2: everyone who's sent in their questions and hopefully we answered

1118
00:52:53,520 --> 00:52:54,080
Speaker 2: them a little bit.

1119
00:52:54,239 --> 00:52:56,360
Speaker 1: And I hope we give you confidence that whatever the

1120
00:52:56,400 --> 00:52:59,560
Speaker 1: scientists uncover about the crazy natures of the universe, eventually

1121
00:52:59,640 --> 00:53:01,040
Speaker 1: and hear and we'll save us.

1122
00:53:01,239 --> 00:53:02,960
Speaker 2: That's right, a super engineer.

1123
00:53:03,239 --> 00:53:04,800
Speaker 1: They're all superheroes in my book.

1124
00:53:04,800 --> 00:53:06,920
Speaker 2: All Right, Well, we hope you enjoyed that. Thanks for

1125
00:53:07,000 --> 00:53:08,960
Speaker 2: joining us, See you next time.

1126
00:53:16,760 --> 00:53:19,560
Speaker 1: Thanks for listening, and remember that Daniel and Jorge Explain

1127
00:53:19,600 --> 00:53:23,600
Speaker 1: the Universe is a production of iHeartRadio. For more podcasts

1128
00:53:23,600 --> 00:53:28,280
Speaker 1: from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever

1129
00:53:28,320 --> 00:53:30,080
Speaker 1: you listen to your favorite shows.