Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions 7

Transcript

Listener Questions 7 · Daniel and Kelly’s Extraordinary Universe

• 0:08
  Speaker 1: Hey, Daniel, have we gotten any exciting messages in our
• 0:11
  Speaker 1: podcast mailbox recently? Oh? Yeah, I gotta say it's kind
• 0:15
  Speaker 1: of refreshing because now the questions in the inbox are
• 0:17
  Speaker 1: mostly back to asking science questions. Back to asking science questions.
• 0:22
  Speaker 1: What do you mean have they not always been about science? Well,
• 0:25
  Speaker 1: you know, until a couple of weeks ago, most of
• 0:28
  Speaker 1: the questions we're asking something else. Here's an example. Hi,
• 0:32
  Speaker 1: Daniel Horror. Hey, this is Oliver and I am a
• 0:34
  Speaker 1: very important question about the universe. Where is Horgey? Thanks?
• 0:39
  Speaker 1: I love your show. Oh that's so cute. Thanks. Thanks
• 0:44
  Speaker 1: for the concern, Oliver. But do you prefer science questions? Daniel?
• 0:50
  Speaker 1: Science questions have answers, you know, science questions or something.
• 0:53
  Speaker 1: I'm supposed to be an expert about. Where Jorge is
• 0:56
  Speaker 1: nobody knows. Hi. I'm or Hamm, a cartoonists and the
• 1:15
  Speaker 1: creator of peach d Comics. Hi. I'm Daniel Whitson. I'm
• 1:19
  Speaker 1: a particle physicist and an avid answer of listener questions.
• 1:23
  Speaker 1: Welcome to our podcast, Daniel and Jorge Explain the Universe,
• 1:26
  Speaker 1: a production of I Heart Radio. Yeah, this is our
• 1:30
  Speaker 1: podcast where we talk about the great Big Unknown questions
• 1:34
  Speaker 1: of the universe, what's going on out there? And often
• 1:37
  Speaker 1: we deal with the questions at the forefront of science.
• 1:39
  Speaker 1: What are scientists thinking, what are they trying to figure out? Zooming?
• 1:43
  Speaker 1: You are all around the universe to take you to
• 1:45
  Speaker 1: the forefront of science and explain it to you. But
• 1:47
  Speaker 1: sometimes we also like to answer questions not just in
• 1:50
  Speaker 1: the minds of scientists, but in the minds of everybody
• 1:53
  Speaker 1: out there. Sometimes I bet some of the great questions
• 1:55
  Speaker 1: and science come from just regular people wondering about this
• 1:58
  Speaker 1: kind of stuff. Hey, socientists are regular people? Are you
• 2:01
  Speaker 1: suggesting we're not? What what you think? I put on
• 2:06
  Speaker 1: that lab code and all of a sudden I become
• 2:07
  Speaker 1: somebody else. Yeah, you become irregular. I'm going to take
• 2:12
  Speaker 1: that in the best way possible. But I think you're right.
• 2:16
  Speaker 1: I agree with you. I think that a lot of
• 2:18
  Speaker 1: the questions that are at the forefront of science, the
• 2:20
  Speaker 1: questions that are burning, that are deep, that are fascinating,
• 2:23
  Speaker 1: our questions that everybody has because everybody wants to know
• 2:26
  Speaker 1: the answer to questions about the universe. People wonder how
• 2:29
  Speaker 1: do things work, and how do they start? And could
• 2:31
  Speaker 1: we blow up planets? And you know, these are basic
• 2:33
  Speaker 1: questions everybody wants to know the answer to. Yes, So
• 2:35
  Speaker 1: to the on the episode. This will be I think
• 2:38
  Speaker 1: maybe episode seven in our series of answering listener questions.
• 2:42
  Speaker 1: So today we have some really interesting questions here about
• 2:46
  Speaker 1: what happens when black holes are born and whether or
• 2:51
  Speaker 1: not we can build something out of a nineteen six movie.
• 2:56
  Speaker 1: That's right, and we love answering listener questions. If you
• 2:58
  Speaker 1: have a question about the universe you'd like us to answer,
• 3:01
  Speaker 1: please send it to us at questions at Daniel and
• 3:03
  Speaker 1: Jorge dot com. We right back to every email, hopefully
• 3:06
  Speaker 1: with an insiphle answer, and sometimes we even feature those
• 3:09
  Speaker 1: questions here on the podcast. Yeah, we answered everything except
• 3:12
  Speaker 1: where I am that one? Oh No, I right back,
• 3:16
  Speaker 1: and I just say, I don't know. I just work
• 3:19
  Speaker 1: with this guy like three different projects. How would I know? Yeah,
• 3:25
  Speaker 1: that's basically it. Yeah, So today on the podcast we'll
• 3:27
  Speaker 1: be answering listener questions, and we have what happens at
• 3:36
  Speaker 1: the moment a black hole is made? Can we build
• 3:39
  Speaker 1: a death star? Those are the burning questions in our
• 3:42
  Speaker 1: listeners minds, and I just want to encourage you one
• 3:45
  Speaker 1: more time to send us to your questions. Sometimes I
• 3:47
  Speaker 1: know the answer run off the bat, but sometimes I
• 3:49
  Speaker 1: have to go do a little bit of research. Talk
• 3:52
  Speaker 1: to an expert on black holes, talk to an expert
• 3:54
  Speaker 1: about death stars, and that's a lot of fun. So
• 3:57
  Speaker 1: please continue to send in your questions, not just because
• 4:00
  Speaker 1: it sends me down rabbit holes where I get to
• 4:02
  Speaker 1: learn about crazy stuff, but also because if you have
• 4:05
  Speaker 1: a question about the universe, probably somebody else does too. Wait, Dinel,
• 4:08
  Speaker 1: I have two questions just from what you just said.
• 4:10
  Speaker 1: First of all, you're you're not an expert at at
• 4:12
  Speaker 1: everything in the universe. I'm an expert at putting on
• 4:16
  Speaker 1: a lab coat and sounding like an expert who gave
• 4:19
  Speaker 1: you a microphone? What? And the second question is that
• 4:23
  Speaker 1: there's actually an expert on death stars out there in
• 4:26
  Speaker 1: your department or in some university. Yes, absolutely, they are experts.
• 4:31
  Speaker 1: In astro industry. You know you're gonna build something really big.
• 4:35
  Speaker 1: You're not going to assemble it on the surface of
• 4:36
  Speaker 1: the Earth. You're gonna have to build it in space.
• 4:38
  Speaker 1: And surprisingly people have thought about that astro engineering. Yeah,
• 4:43
  Speaker 1: astro engineering. Can you study that in college? Can I
• 4:46
  Speaker 1: study that in college? Not today, not tomorrow, but coming
• 4:52
  Speaker 1: soon to a rebel planet near you. Maybe we should
• 4:54
  Speaker 1: take a page from our president and just call it
• 4:57
  Speaker 1: a space engineer Space force engineering US spence much time
• 5:00
  Speaker 1: wondering if you could build a death star. You never
• 5:02
  Speaker 1: thought to ask if you should. Yeah, but we love
• 5:04
  Speaker 1: getting questions from listeners, and so today the first question
• 5:08
  Speaker 1: we have is from Glenn, who is from Cape Town,
• 5:10
  Speaker 1: South Africa. And Glenn has a pretty interesting question which
• 5:14
  Speaker 1: I don't think we've ever covered here, right, No, we
• 5:17
  Speaker 1: certainly have not. We've talked a lot about black holes,
• 5:19
  Speaker 1: but we've never really asked or answered this specific question. Yeah, so,
• 5:23
  Speaker 1: and um, it's a pretty cool question. And so here
• 5:26
  Speaker 1: is Glenn from Cape Town, South Africa. Hi, Daniel and Joge.
• 5:30
  Speaker 1: This is Glenn Edwards and I'm from Cape Town, South Africa.
• 5:34
  Speaker 1: I'm pretty interested in all things space related and I've
• 5:36
  Speaker 1: been really enjoying your podcasts. I've heard a lot of
• 5:39
  Speaker 1: different discussions about black holes, so I have a very
• 5:42
  Speaker 1: basic understanding about the factors that lead up to its formation.
• 5:46
  Speaker 1: One thing, however, that I've never heard about, is the
• 5:48
  Speaker 1: actual mechanics of the moment of black hole begins when
• 5:51
  Speaker 1: extremely dense cosmic object collapses into a black hole. Is
• 5:55
  Speaker 1: this an instantaneous event or something that happens over cosmic
• 5:58
  Speaker 1: time frames? If you are observing this object at the
• 6:01
  Speaker 1: moment of collapse, would it suddenly go out like a light?
• 6:05
  Speaker 1: Have any black hole formation has ever been observed? Would
• 6:08
  Speaker 1: anything within the Schwartz Child radius suddenly disappear? That's a
• 6:13
  Speaker 1: lot to unpeck, but I'm looking forward to hearing your
• 6:15
  Speaker 1: entertaining answers. All Right, Basically, I think the question is
• 6:18
  Speaker 1: what does the baby black hole look like? For or
• 6:22
  Speaker 1: maybe it's more like a bird's in the best question
• 6:25
  Speaker 1: about black hole? Yeah, I think he wants to see
• 6:27
  Speaker 1: the black hole pop out. He's curious about that transition
• 6:30
  Speaker 1: from not black hole to black hole? What does that
• 6:33
  Speaker 1: look like? How does it happen? This kind of stuff, Yeah,
• 6:35
  Speaker 1: because you know, we have sort of pictures now of
• 6:37
  Speaker 1: what a black hole, an adult black hole looks like,
• 6:40
  Speaker 1: but we don't know kind of like the process of
• 6:43
  Speaker 1: making a black hole. Yeah, really a fascinating question. How
• 6:46
  Speaker 1: does that happen, How fast does it happen? What would
• 6:48
  Speaker 1: it look like if you were there watching? This really
• 6:51
  Speaker 1: goes to the heart of what it's like to be
• 6:53
  Speaker 1: a black hole and how the black hole has made
• 6:55
  Speaker 1: So I thought this was a really fascinating question and
• 6:57
  Speaker 1: actually went down and spent like an hour of talking
• 7:00
  Speaker 1: to an expert in my department, Aaron Barth, who's an
• 7:02
  Speaker 1: expert in black holes supermassive and not supermassive about exactly
• 7:06
  Speaker 1: what this would look like. Super fun. Thank you Glenn
• 7:08
  Speaker 1: for this excellent question. That's the question, And it's like,
• 7:10
  Speaker 1: if you were out in space watching the birth of
• 7:13
  Speaker 1: a black hole, what would you see? Would you would
• 7:16
  Speaker 1: you even survive the experience? I guess this is my
• 7:19
  Speaker 1: main question. Do we want to see a black hole
• 7:22
  Speaker 1: get born? Well, maybe if you were watching it from
• 7:24
  Speaker 1: the viewing portal of a death star and had like,
• 7:26
  Speaker 1: you know, a lot of protection, then you could survive
• 7:29
  Speaker 1: at force field a force field. But I think the
• 7:31
  Speaker 1: first thing to understand is sort of the time scale
• 7:34
  Speaker 1: of the process, Like how rapidly does a black hole
• 7:37
  Speaker 1: get formed? Like how quickly do you go from star
• 7:39
  Speaker 1: to black hole? Is it like geological cosmological time scales
• 7:43
  Speaker 1: of hundreds of millions of years or does it happen
• 7:45
  Speaker 1: really fast? I think that was the first question that
• 7:48
  Speaker 1: popped into my head when I read this. My question is, um,
• 7:51
  Speaker 1: what reminds me what a black hole is? Or like,
• 7:55
  Speaker 1: what's a technical definition so that we know at what
• 7:58
  Speaker 1: point it is a black hole? Right? Good point? So
• 8:02
  Speaker 1: a black hole is any location in the universe where
• 8:05
  Speaker 1: gravity is so strong that nothing can escape its gravitational field,
• 8:10
  Speaker 1: and an area of volume of space or like a point,
• 8:14
  Speaker 1: or it's a it's a volume of space, it's like
• 8:17
  Speaker 1: a sphere, and we don't know what's inside the sphere.
• 8:20
  Speaker 1: We don't know how the matter is distributed. A lot
• 8:22
  Speaker 1: of people have their an image in their mind of
• 8:24
  Speaker 1: a point like a singularity, a super dense point inside
• 8:28
  Speaker 1: the black hole that has so much mass that the
• 8:31
  Speaker 1: gravity around it is really strong. And that's the picture
• 8:34
  Speaker 1: you have from general relativity. And we know the general
• 8:37
  Speaker 1: relativity is a great theory. The university describes a lot
• 8:40
  Speaker 1: of things correctly. We don't know that it's correctly describing
• 8:43
  Speaker 1: what's happening inside a black hole, but it's it's a
• 8:45
  Speaker 1: good starting point. And and the structure there is you
• 8:48
  Speaker 1: have a dense dot and the singularity huge amount of mass,
• 8:52
  Speaker 1: and then at some radius, some distance from the black
• 8:55
  Speaker 1: hole or closer, the gravity is too strong for anything
• 8:58
  Speaker 1: to escape, and that's what we sort of called the
• 9:00
  Speaker 1: surface the black hole. It's a three D hole, right,
• 9:03
  Speaker 1: like a it's like a sphere, but it's a whole. Yeah,
• 9:08
  Speaker 1: in space. I think if it's sort of like a
• 9:10
  Speaker 1: like a trap in space, like once you get in there,
• 9:12
  Speaker 1: you can't get out. That space is sort of one directional,
• 9:15
  Speaker 1: Like you get in there and all you can do
• 9:16
  Speaker 1: is move closer to the center of the black hole.
• 9:18
  Speaker 1: You can't ever move further from the center. Um in
• 9:22
  Speaker 1: some sense, like you just call it a trap trap hole.
• 9:26
  Speaker 1: I think that was vetoed is not safe to work um.
• 9:31
  Speaker 1: And one useful thing to remember is that it's not
• 9:33
  Speaker 1: like gravity is pulling on photons and slowing them down,
• 9:37
  Speaker 1: but eventually they will escape. They cannot escape, and not
• 9:40
  Speaker 1: just because gravity is so strong, but because gravity is
• 9:42
  Speaker 1: actually bent the space. You know, there's there's no path
• 9:46
  Speaker 1: outside the black hole. Like every direction you move you're
• 9:49
  Speaker 1: inside the black hole takes you closer because space is
• 9:52
  Speaker 1: bent in a really weird way inside the black hole.
• 9:55
  Speaker 1: So it's not like it it grabs things and holds
• 9:57
  Speaker 1: them with some force. It's like it's like it's really
• 10:00
  Speaker 1: kind of like a pocket in space. It's like a
• 10:02
  Speaker 1: hole in space itself. Like you once you go in there,
• 10:05
  Speaker 1: you're trapped in It's in your own little space, that's right.
• 10:09
  Speaker 1: And it's not like quicksand right where it's just like
• 10:11
  Speaker 1: slows you down. It's hard to climb out, but if
• 10:13
  Speaker 1: you try really really hard or whatever, um there's just
• 10:15
  Speaker 1: no way to do it. And so it's like a trap.
• 10:17
  Speaker 1: It's like a hole in space. And and the point
• 10:20
  Speaker 1: I wanted to make earlier was that we know this
• 10:22
  Speaker 1: surface exists, We know the black holes are real, and
• 10:24
  Speaker 1: that there's this event horizon the surface beyond which if
• 10:27
  Speaker 1: you pass you can never escape. We don't know what's
• 10:30
  Speaker 1: going on inside there, because we don't really know if
• 10:33
  Speaker 1: general relativity is correct at these really really strong gravitational fields,
• 10:36
  Speaker 1: and quantum mechanics says it's probably wrong, but we've never
• 10:40
  Speaker 1: looked inside a black hole, so we can't quite tell.
• 10:42
  Speaker 1: But it is um, like you said, it does have
• 10:44
  Speaker 1: sort of a surface reboundary, and so it's a it's
• 10:47
  Speaker 1: a thing, And so I guess the question is like,
• 10:49
  Speaker 1: how does that thing get formed? Does it started really
• 10:52
  Speaker 1: small and then grow or does it immediately pop into existence?
• 10:56
  Speaker 1: You just go online to Amazon and you enter black
• 10:58
  Speaker 1: hole and you press by now and boom, there's your
• 11:01
  Speaker 1: black hole. There's a buy now button for the universe
• 11:04
  Speaker 1: only for Prime Now I get black hole Prime delivery. Um,
• 11:08
  Speaker 1: it's it's quantum Amazon. I was actually thinking about that
• 11:11
  Speaker 1: because the gravitational information travels at a finite speed. Right.
• 11:15
  Speaker 1: If you create a black hole as a singularity, then
• 11:19
  Speaker 1: the space around it doesn't know about the black hole instantly,
• 11:22
  Speaker 1: so it takes like a moment for the black hole
• 11:24
  Speaker 1: the sphere to sort of be created and to travel
• 11:28
  Speaker 1: out to the eventual event horizon. There's like a huge
• 11:30
  Speaker 1: gravitational wave that would be created if you were able
• 11:33
  Speaker 1: to Amazon prime singularity into existence. Yeah, the question is
• 11:37
  Speaker 1: if you instantly pop a singularity out into space, Um,
• 11:40
  Speaker 1: what happens? Right, Like you're saying, it may not. It
• 11:43
  Speaker 1: might propagate out slowly, or it might um who knows, right,
• 11:46
  Speaker 1: because it's bending space at the same time. So it's
• 11:48
  Speaker 1: it's kind of weird, right. Yeah. If you were a
• 11:50
  Speaker 1: photon and you're flying in some direction and somebody creates
• 11:53
  Speaker 1: a black hole right behind you, in theory, you could
• 11:57
  Speaker 1: survive even if you're right next to that singular already
• 12:00
  Speaker 1: because you could like travel faster than the gravitational waves
• 12:04
  Speaker 1: that are propagatting out from the singularity to sort of
• 12:06
  Speaker 1: inform the rest of the universe that singularity have been created.
• 12:10
  Speaker 1: Because remember, gravitational information is not instantaneous. The Sun disappeared,
• 12:14
  Speaker 1: for example, the Earth would keep moving in its orbit
• 12:17
  Speaker 1: for eight minutes until it got updated. Right, It's like
• 12:20
  Speaker 1: that scene in every other action movie where there's an
• 12:23
  Speaker 1: explosion or a tidal wave or something and the heroes
• 12:25
  Speaker 1: are in their plane or a car just barely outrunning
• 12:29
  Speaker 1: the shock wave. No no, no, no, exactly they die
• 12:33
  Speaker 1: from the burning building. But that's not the way black
• 12:36
  Speaker 1: holes are actually made in our universe. It's just sort
• 12:38
  Speaker 1: of like the extreme example, black holes come from huge
• 12:41
  Speaker 1: masses that already exist. Okay, so let's step through that
• 12:43
  Speaker 1: how exactly black holes are made and what maybe actually
• 12:47
  Speaker 1: happens when they get made. But first let's take a
• 12:50
  Speaker 1: quick break. Okay, Daniel, So how do I make a
• 13:05
  Speaker 1: black hole? What's the what's the recipe here? It's a
• 13:08
  Speaker 1: huge blob of stuff and that's about it. Get a
• 13:12
  Speaker 1: huge blob tablespoons of the zillion tablespoons of anything and
• 13:17
  Speaker 1: then mix. That's the recipe. You don't even have to mix.
• 13:20
  Speaker 1: You just wait, you know, preheat the oven to two
• 13:22
  Speaker 1: point seven three degrees kelvin. That's a temperature of the universe.
• 13:25
  Speaker 1: And then just wait hundreds of millions of years. Well,
• 13:28
  Speaker 1: you kind of have to um make a dough in
• 13:31
  Speaker 1: no way, right, You have to get it on the
• 13:33
  Speaker 1: in a certain amount of space. Like, you don't just
• 13:35
  Speaker 1: need a lot of stuff. You need a lot of
• 13:37
  Speaker 1: stuff in a small amount of space. Yeah, And that's
• 13:39
  Speaker 1: what gravity will do for you. Given enough time, gravity
• 13:42
  Speaker 1: will pull together a huge blob of gas and squeeze
• 13:45
  Speaker 1: it and eventually squeeze it so much that becomes a
• 13:47
  Speaker 1: star if it's big enough, and that star will burn.
• 13:51
  Speaker 1: And the reason it doesn't just immediately compress it into
• 13:53
  Speaker 1: a black hole is because of the burning. The burning
• 13:56
  Speaker 1: creates a lot of energy. It's like radiation that's pushing out,
• 13:59
  Speaker 1: so keeps it from collapsing anymore. Like you might wonder
• 14:02
  Speaker 1: why doesn't every blob of gas just immediately turn into
• 14:05
  Speaker 1: a black hole, It's because there's some force outwards and
• 14:07
  Speaker 1: that comes from this fusion. It's burning, and so it's
• 14:10
  Speaker 1: kind of diffusing the stuff out, making it fluffy, not
• 14:14
  Speaker 1: concentrated exactly. It's a constantly exploding fusion bomb, so it's
• 14:18
  Speaker 1: throwing everything out really hard. At the same time gravity
• 14:21
  Speaker 1: is pulling in, so it's a delicate balance. A star,
• 14:24
  Speaker 1: it's this exploding bomb that's trapped by its own gravitational power,
• 14:28
  Speaker 1: and that goes on for hundreds of millions of years,
• 14:31
  Speaker 1: depending precisely on the size of the star, etcetera, while
• 14:33
  Speaker 1: it burns all that fuel. Okay, so then how does
• 14:36
  Speaker 1: a black hole get formed or how do what are
• 14:38
  Speaker 1: the different wayte black holes come to exist in our universe? Well,
• 14:42
  Speaker 1: the thing that's preventing a star from being a black
• 14:44
  Speaker 1: hole immediately is this burning and so essentially you have
• 14:46
  Speaker 1: to wait for the fire to go out. After hundreds
• 14:48
  Speaker 1: of millions of years, it's turned that hydrogen into helium
• 14:51
  Speaker 1: and then into lithium and into heavier stuff, and that
• 14:53
  Speaker 1: stuff can burn also, but eventually it turns into something
• 14:56
  Speaker 1: that can't burn, which is iron, and so it runs
• 14:59
  Speaker 1: out of fuel. Most black holes come from stars? Is
• 15:03
  Speaker 1: that is that the path through a black hole? Or
• 15:06
  Speaker 1: can a black hole form any other way that's not
• 15:08
  Speaker 1: through a star? We're not exactly sure, like the supermassive
• 15:12
  Speaker 1: black holes that at the center of galaxies, we still
• 15:14
  Speaker 1: don't know what seated them, Like if you try to
• 15:17
  Speaker 1: model them just from coming from one star and then
• 15:18
  Speaker 1: gobbling up other ones, there's not enough time for them
• 15:21
  Speaker 1: to get that big, and so there's lots of different
• 15:23
  Speaker 1: categories of black holes. But we think that's sort of
• 15:25
  Speaker 1: your vanilla black hole that comes from a star happens
• 15:28
  Speaker 1: in this way, but we don't know if that's the
• 15:31
  Speaker 1: dominant fraction of black holes. Also, some black holes might
• 15:33
  Speaker 1: have been made at the Big Bang. They're called primordial
• 15:36
  Speaker 1: black holes, and those could still be flying around they
• 15:38
  Speaker 1: were made in the Big Bang. Yeah, these are the
• 15:40
  Speaker 1: o G black holes. So as the as the universe
• 15:44
  Speaker 1: was expanding rapidly, like, that's how you got black holes. Yeah, Well,
• 15:48
  Speaker 1: there was crazy energy density back then in the very
• 15:50
  Speaker 1: first moment of the universe, and you quantum fluctuations and
• 15:53
  Speaker 1: made some spots more dense and some spots less dense,
• 15:56
  Speaker 1: and then all that stuff turned into all that energy
• 15:58
  Speaker 1: turned into some kind of matter. Some it became very
• 16:00
  Speaker 1: on it and became dark matter. Some fraction that we
• 16:03
  Speaker 1: think might have turned into primordial black holes, which is
• 16:05
  Speaker 1: just a cool word. Primordial black holes. Yeah, it's like
• 16:09
  Speaker 1: a black hole emerging from the swamp. That's what I
• 16:11
  Speaker 1: have this image in my head, swamp of what the
• 16:16
  Speaker 1: swamp of the early universe, you know, pretty big bang. Yeah.
• 16:20
  Speaker 1: So you say, most black holes we don't know how
• 16:22
  Speaker 1: they're made, the big ones and the ones that were
• 16:24
  Speaker 1: at the beginning of the universe. But a lot of
• 16:26
  Speaker 1: the black holes we know about and see do come
• 16:28
  Speaker 1: from a process that we know about, which is from
• 16:31
  Speaker 1: collapsing stars. So it burns through all this fuel that's
• 16:34
  Speaker 1: keeping it from collapsing, and it gets heavier and heavier
• 16:37
  Speaker 1: and denser and denser, and then once it gets enough
• 16:39
  Speaker 1: iron in the core, it can't support itself anymore. Gravity
• 16:42
  Speaker 1: basically wins, and it starts crushing the star down even
• 16:46
  Speaker 1: more and more dense, and then there's I then that's
• 16:49
  Speaker 1: when it's super novas, right, Like, there's an event the
• 16:53
  Speaker 1: black hole, and you know, like every good movie, the
• 16:55
  Speaker 1: sort of drama accelerates. The first stage is really long
• 16:58
  Speaker 1: and boring set up, like hundreds of millions of years
• 17:00
  Speaker 1: of burning hydrogen, and then it burns helium and that's
• 17:03
  Speaker 1: less time, and then it burns lithium or whatever, and
• 17:05
  Speaker 1: that's less time in the last stage where it's like
• 17:07
  Speaker 1: trying to burn iron, that last for about one hour
• 17:10
  Speaker 1: and then it collapses and it's like that happens in
• 17:14
  Speaker 1: seconds or less than a second, and the edge of
• 17:17
  Speaker 1: the star collapses at something like a quarter of the
• 17:19
  Speaker 1: speed of light. So the whole thing happens like really quickly.
• 17:22
  Speaker 1: You go from star that's sputtering to collapsing, and then
• 17:26
  Speaker 1: the whole star just kind of falls into itself. Yeah,
• 17:31
  Speaker 1: and there's a lot of really interesting physics there, like
• 17:33
  Speaker 1: it's collapsing so rapidly that you get shock waves, and
• 17:36
  Speaker 1: those shock waves we think can create gamma ray bursts
• 17:39
  Speaker 1: when like layers of the star bump into other layers
• 17:42
  Speaker 1: of the star that aren't quite collapsing as quickly. We
• 17:44
  Speaker 1: talked on this podcast once about these gamma ray bursts,
• 17:47
  Speaker 1: hugely intense bursts of light that lasts like three or
• 17:50
  Speaker 1: thirty seconds that come from places we don't understand. It
• 17:53
  Speaker 1: might be the themes are happening sort of at these
• 17:55
  Speaker 1: moments just before the supernova, at the creation of the
• 17:58
  Speaker 1: black hole, but we're not sure. And it collapses from
• 18:01
  Speaker 1: gravity right like there's no longer a fire kind of
• 18:04
  Speaker 1: keeping everything out, and so everything just finally says, all right,
• 18:07
  Speaker 1: we'll come together as gravity tells us precisely, and gravity
• 18:11
  Speaker 1: just gets stronger and stronger a right. Gravity is just
• 18:14
  Speaker 1: sort of like winds, you know, it's like interest in
• 18:16
  Speaker 1: your bank account. The closer stuff it gets together, the
• 18:19
  Speaker 1: more gravity pulls. The more gravity pulls, the closer it
• 18:22
  Speaker 1: gets together, and then it accelerates, and so it gets
• 18:24
  Speaker 1: really really strong. And then at some moment the gravity
• 18:26
  Speaker 1: is strong enough that you get an event horizon that's formed. Oh,
• 18:30
  Speaker 1: I say, it's pulling stuff in so quickly that you
• 18:35
  Speaker 1: do get the conditions for a black hole. We talked
• 18:38
  Speaker 1: before about like neutron stars. And sometimes a supernova doesn't
• 18:42
  Speaker 1: result in a black hole, right, Sometimes it does, that's right.
• 18:45
  Speaker 1: Sometimes it can come down to another dense state that's stable,
• 18:48
  Speaker 1: like a neutron star. Everything has been squeezed so much
• 18:52
  Speaker 1: that all the protons have absorbed electrons and turned into neutrons,
• 18:55
  Speaker 1: and they've created this state that they can hold themselves
• 18:58
  Speaker 1: together and resist gravity, like one last more gasp before
• 19:02
  Speaker 1: it turns into a black hole. But sometimes it go
• 19:04
  Speaker 1: straight to a black hole, right, And the difference is
• 19:06
  Speaker 1: that just at the rate of how fast it collapsed
• 19:09
  Speaker 1: or what. Most of the difference is the initial amount
• 19:11
  Speaker 1: of stuff. If you have a big enough blob, then
• 19:14
  Speaker 1: I think you get to skip the neutron star step
• 19:16
  Speaker 1: and just go straight to a black hole. The whole
• 19:18
  Speaker 1: thing happens more quickly the more mass you have. And
• 19:21
  Speaker 1: really it's about density. I think you said once in
• 19:23
  Speaker 1: the podcast, which is cool, that anything can become a
• 19:26
  Speaker 1: black hole if you make it dense enough. And so
• 19:28
  Speaker 1: we're not changing the mass of this initial blob of gas,
• 19:31
  Speaker 1: We're just squeezing it down. At some point you make
• 19:33
  Speaker 1: it dense enough, then you have more mass and less
• 19:36
  Speaker 1: space than the gravity becomes strong enough to give you
• 19:39
  Speaker 1: an event horizon. Right like you, You can be become
• 19:42
  Speaker 1: a black hole. I can become a black hole. Everyone
• 19:44
  Speaker 1: can be black if we're all o g black holes.
• 19:48
  Speaker 1: I'm not primordial, man, I've been around to the Big
• 19:51
  Speaker 1: Bang and you feel old. But gez, just because you
• 19:53
  Speaker 1: get reading glasses, it doesn't make your primordial. No, that
• 19:59
  Speaker 1: just makes me hyper my myopic. Um. And then it
• 20:03
  Speaker 1: gets sort of back to this moment we were talking
• 20:05
  Speaker 1: about before, when we like Amazon Prime to singularity into existence,
• 20:08
  Speaker 1: because at some moment there's no event horizon, right, it's
• 20:10
  Speaker 1: just a hot, dense star. And then at some moment
• 20:13
  Speaker 1: there is because there's enough stuff there. It's a supernova.
• 20:16
  Speaker 1: And I hit the pause button and I'm stepping through
• 20:19
  Speaker 1: it super high speed frame by super high speed frame,
• 20:22
  Speaker 1: and I'm seeing it collapse, collapse, collapse, and at some
• 20:26
  Speaker 1: point I have enough stuff within a certain volume to
• 20:30
  Speaker 1: qualify as a black hole precisely. And I think the
• 20:33
  Speaker 1: first moment the event horizon is essentially minuscule is because
• 20:37
  Speaker 1: the densest point is going to be the very center
• 20:39
  Speaker 1: of this star, and that's the first place it's going
• 20:41
  Speaker 1: to cross that density threshold. And then as it gets
• 20:44
  Speaker 1: gobble stuff up, that event horizon is going to grow.
• 20:47
  Speaker 1: And it's not going to grow at the speed of
• 20:49
  Speaker 1: light because that would that would require all the mass
• 20:51
  Speaker 1: to move into the center instantaneously. But it's going to
• 20:54
  Speaker 1: gobble more stuff and then grow quickly out to its
• 20:57
  Speaker 1: eventual size. Interesting, and when you know that first, sure
• 21:00
  Speaker 1: that the center gets danses first, like you know, because
• 21:04
  Speaker 1: you could imagine just the whole thing collapsing from the
• 21:08
  Speaker 1: edges and at some point you just have enough stuff
• 21:11
  Speaker 1: to just have a giant black hole without its starting
• 21:14
  Speaker 1: in the middle. And the other idea is that it
• 21:16
  Speaker 1: could all transition at the same moment, is what you're saying, Yeah,
• 21:20
  Speaker 1: like it. Yeah. I don't think we know the gory
• 21:22
  Speaker 1: details of this collapse well enough to say how rapidly
• 21:25
  Speaker 1: the center versus the edge turns into a black hole.
• 21:27
  Speaker 1: But I think it's if it's gonna be anything, it's
• 21:30
  Speaker 1: going to be the center first, because that's definitely what
• 21:31
  Speaker 1: the strongest gravity is. It might be that the whole
• 21:34
  Speaker 1: thing happens very quickly. I'm not sure exactly about the
• 21:37
  Speaker 1: relative rate of the edge to the center, but it's
• 21:40
  Speaker 1: definitely gonna be the center first. Okay, So the ideas
• 21:42
  Speaker 1: that maybe probably what's happening is that there's a mini
• 21:46
  Speaker 1: black hole that's born at the middle of this collapsing star,
• 21:50
  Speaker 1: and as more stuff comes into it, it grows. Yeah,
• 21:53
  Speaker 1: and so and remember the threshold we're just we're talking
• 21:56
  Speaker 1: about the definition of the black hole is that where
• 21:58
  Speaker 1: that event horizon is. And that's not a physical thing.
• 22:00
  Speaker 1: It's not like you can touch it. It's just a
• 22:02
  Speaker 1: place inside of which there's too much gravity to escape
• 22:05
  Speaker 1: and outside of which there isn't And so it's just
• 22:08
  Speaker 1: like a mathematical definition. If you're actually on the border
• 22:11
  Speaker 1: between give and horizon or not, you wouldn't like your
• 22:14
  Speaker 1: life doesn't change that much. You go in from one
• 22:17
  Speaker 1: side of and I mean, like, I mean your toast.
• 22:19
  Speaker 1: You're probably not in a good place. But it's not
• 22:23
  Speaker 1: like suddenly, um, the skies turn you know, some weird color.
• 22:27
  Speaker 1: You feel different. It's like, no, you are a speghettified
• 22:32
  Speaker 1: piece of toast. But yeah, there's nothing physically different there
• 22:35
  Speaker 1: other than the strength of gravity is now above some
• 22:37
  Speaker 1: threshold rather than below. So I don't think qualitatively it
• 22:40
  Speaker 1: feels very different, except that now everywhere you look in
• 22:43
  Speaker 1: the universe is towards the center of the black hole.
• 22:46
  Speaker 1: I see, you would see like space around you warping, warping, warping,
• 22:49
  Speaker 1: and then suddenly, whoop, it all occurs in on itself. Yeah, precisely.
• 22:54
  Speaker 1: And then every direction you look would be in towards
• 22:56
  Speaker 1: the inside of the black hole. So everything that's outside
• 22:58
  Speaker 1: the black hole would be shrinking down eventually to a
• 23:01
  Speaker 1: dot and then disappear, And then everywhere you look would
• 23:04
  Speaker 1: be inside the black hole. There's no direction you can
• 23:06
  Speaker 1: go that's outside the black hole, and then you're trapped
• 23:09
  Speaker 1: forever and you are trapped or maybe you're on the
• 23:12
  Speaker 1: other side of something who knows, right, Yeah, so let's
• 23:14
  Speaker 1: talk about that. What it looks like from the other side.
• 23:16
  Speaker 1: I think that's pretty cool, like from inside or outside,
• 23:19
  Speaker 1: from outside, because I think his question was like, what
• 23:21
  Speaker 1: does it look like to see a black hole get made?
• 23:24
  Speaker 1: Does it go out like a light? Okay, so I'm
• 23:26
  Speaker 1: I'm in my Death Star hanging out with Darth and
• 23:30
  Speaker 1: watching the point that thing by the way, maybe we create,
• 23:35
  Speaker 1: maybe we collapse the star. Maybe maybe Darth Vader wanted
• 23:39
  Speaker 1: that's start taking out. Do you think he could reach
• 23:41
  Speaker 1: out with a force and squeeze a star the way
• 23:43
  Speaker 1: he can squeeze somebody's neck? Depend somebody medichlorians there are
• 23:46
  Speaker 1: probably I don't know, somebody needs to do a blood test. Yeah.
• 23:50
  Speaker 1: So you're you're on the deck of your Death Star,
• 23:51
  Speaker 1: hanging out with your buddy Dark. Yeah, you primed the
• 23:54
  Speaker 1: force fields and you see this star suddenly collapse boom um.
• 23:59
  Speaker 1: So we see the star shrink really fast and then
• 24:03
  Speaker 1: there's an explosion, right, because all that stuff when it collapses,
• 24:06
  Speaker 1: it like creates stock waves, right like yeah, because not
• 24:11
  Speaker 1: all the stuff falls in, right, some of it gets
• 24:13
  Speaker 1: thrown out, and you get this gamma ray burst, and
• 24:15
  Speaker 1: you get neutrinos, and you get a huge flash of light.
• 24:18
  Speaker 1: But then the star is gone. Right when the flash
• 24:21
  Speaker 1: of light is past you and all that, you know,
• 24:24
  Speaker 1: the hoopla and the drama of the universe has passed you,
• 24:28
  Speaker 1: then the star is just no longer they're burning, right. Instead,
• 24:31
  Speaker 1: all that light that was being produced by the star
• 24:33
  Speaker 1: is no longer being produced because it's no more fusion happening. Well,
• 24:36
  Speaker 1: will you skip the step of the black hole? So
• 24:38
  Speaker 1: we see the star collapsing, boom, a lot of energy
• 24:42
  Speaker 1: and light and strong waves spread out. And as that's happening,
• 24:46
  Speaker 1: there's a little black hole in the middle growing, right,
• 24:49
  Speaker 1: And so you're gonna be seeing less and less light
• 24:51
  Speaker 1: from the star because more of it's going to be
• 24:53
  Speaker 1: a black hole. And you know, practically you probably can't
• 24:56
  Speaker 1: see this thing happening anyway, because you're inundated by the
• 24:59
  Speaker 1: supernova outburst stuff, the gamma ray burst and all that
• 25:02
  Speaker 1: other stuff is going to totally blind you. But if
• 25:04
  Speaker 1: you could somehow see through that and watch what was
• 25:07
  Speaker 1: happening in the core. Then you're right. You'd see sort
• 25:09
  Speaker 1: of the center of the star be hollowed out and
• 25:11
  Speaker 1: turned into a black hole. And so the Star Wars
• 25:14
  Speaker 1: is beginning dimmer and dimmer. If you were wearing like
• 25:16
  Speaker 1: Gamma ray bands, could you just come up with that,
• 25:21
  Speaker 1: that is awesome as a special Gamma ray bands that
• 25:26
  Speaker 1: blocked thegether. You would see the star in the middle
• 25:28
  Speaker 1: like you would see this little black dot just grow
• 25:31
  Speaker 1: into a black circle. Right, Well, you wouldn't see the
• 25:33
  Speaker 1: dot to be at the center of the star, so
• 25:35
  Speaker 1: you'd be looking at the surface of the star, which
• 25:37
  Speaker 1: would be you know, collapsing and doing its thing and
• 25:39
  Speaker 1: maybe still burning in emitting light, but be eaten up
• 25:42
  Speaker 1: from the inside probably, And so you'd be seeing the
• 25:45
  Speaker 1: star get dimmer and dimmer because it's no longer supported
• 25:48
  Speaker 1: by fusion in the inside. Oh man, you're saying a
• 25:51
  Speaker 1: black hole eats the star from the inside. Yeah, it's
• 25:55
  Speaker 1: like one of those tarantula wasps. Oh man, Now I
• 25:58
  Speaker 1: think we need to switch to different sci fi movie.
• 26:01
  Speaker 1: Now we're in like an alien that's right. And and
• 26:06
  Speaker 1: so the star basically just goes out right all that
• 26:09
  Speaker 1: stuff that was burning that was producing light stops and
• 26:12
  Speaker 1: is now just sort of inside the black hole, no
• 26:14
  Speaker 1: longer producing the light. And so it doesn't go out
• 26:17
  Speaker 1: like a light. It's not like it just instantly switches off.
• 26:19
  Speaker 1: It used to get eaten from the inside. Wow. And
• 26:23
  Speaker 1: and at some point you'll see the black hole um
• 26:27
  Speaker 1: burst out of the star almost or like just kind
• 26:30
  Speaker 1: of grow out of it, and that's all you see. Yeah,
• 26:32
  Speaker 1: so I think you would see a black circle appure
• 26:36
  Speaker 1: sort of suddenly because the entire last surface of the
• 26:38
  Speaker 1: star would get gobbled up by it. But remember then,
• 26:41
  Speaker 1: the black hole is not like surrounded by empty space.
• 26:43
  Speaker 1: It can't eat everything that's around it. It's always going
• 26:46
  Speaker 1: to be surrounded by some amount of stuff that won't
• 26:48
  Speaker 1: fall in because it's rotating too fast to fall in. Oh,
• 26:51
  Speaker 1: I see, it's like a mess. It's like a it's
• 26:53
  Speaker 1: it's like the center of a tornado. Yeah, precisely, just
• 26:56
  Speaker 1: the way our solar system has a huge blob near
• 26:59
  Speaker 1: the center of the Sun, but not everything fell in, right,
• 27:01
  Speaker 1: The Earth doesn't fall into the center of the Sun
• 27:04
  Speaker 1: even though there's a huge amount of gravity because the
• 27:06
  Speaker 1: Earth is rotating in the same way. The stuff around
• 27:08
  Speaker 1: the black hole keeps spinning and eventually falls in um,
• 27:12
  Speaker 1: but some of it stays there for a long long time,
• 27:15
  Speaker 1: which is why when you look at that picture of
• 27:16
  Speaker 1: the black hole you see a glowing ring, which is
• 27:19
  Speaker 1: the stuff at the edge of the black hole that
• 27:20
  Speaker 1: has not fallen in. It's still spinning around it hundreds
• 27:23
  Speaker 1: of millions of years later, right yeah, and think about
• 27:27
  Speaker 1: what just happened that like a huge star just collapse,
• 27:30
  Speaker 1: and so there's probably it's probably like a super chaotic environment,
• 27:34
  Speaker 1: you know, there's like stuff that just like swirling around
• 27:38
  Speaker 1: from that crash, right yeah, And so probably you're mostly
• 27:41
  Speaker 1: going to be seeing the accretion disk and the stuff
• 27:43
  Speaker 1: swirling around it for a long time because it's a
• 27:45
  Speaker 1: nasty environment. The gravity there, even though it's not black
• 27:48
  Speaker 1: hole levels, it's still really really strong, and that squeezes
• 27:51
  Speaker 1: all that gas and stresses it and then it radiates.
• 27:54
  Speaker 1: So some of the brightest things in the universe are
• 27:57
  Speaker 1: gas that are right outside the edge of a black
• 27:59
  Speaker 1: hole that we call those quasars when they are at
• 28:01
  Speaker 1: the center of a galaxy, and they're extraordinarily bright in
• 28:04
  Speaker 1: X ray and invisible light. But I guess the main
• 28:06
  Speaker 1: thing is that it would be pretty instantaneous, almost right,
• 28:10
  Speaker 1: like maybe you couldn't even see it with the naked eye,
• 28:12
  Speaker 1: which is collapse. Boom, Suddenly there's a black hole in
• 28:15
  Speaker 1: the middle with all this swirling uh you know, gas
• 28:19
  Speaker 1: burning gas and crazy energies swirling around it. Right, it
• 28:23
  Speaker 1: would be sort of like boom, right, precisely, precisely. The
• 28:26
  Speaker 1: actual transition from star to black hole happens very quickly,
• 28:31
  Speaker 1: probably less than a second, but then it takes a
• 28:33
  Speaker 1: while for the sort of clean up the scene of
• 28:35
  Speaker 1: the accident so you can actually see the black hole
• 28:37
  Speaker 1: with your cosmic ray cosmic gamma ray bands on. You
• 28:42
  Speaker 1: have to wait for the dust to settle a little bit,
• 28:44
  Speaker 1: and then you see the black hole precisely, and then
• 28:48
  Speaker 1: you and Darth Vader cut the umbilical cord and your
• 28:52
  Speaker 1: proud parents of a new black hole. That's right. Then
• 28:55
  Speaker 1: you got to give it a name, and then you
• 28:57
  Speaker 1: argue about that, and he probably wins. He's like an
• 29:01
  Speaker 1: a kid. No, no, we already used that one. I
• 29:03
  Speaker 1: am the feeling Darth Vader wins every marital argument, all right,
• 29:09
  Speaker 1: So that answers Glenn's questions. What happens at the moment
• 29:12
  Speaker 1: a black hole is made a lot of stuff and
• 29:16
  Speaker 1: a lot of very quickly. It seems to be the answer.
• 29:18
  Speaker 1: It's a huge, cosmic, beautiful mess. All right. So that
• 29:21
  Speaker 1: answers that question, and we'll get now into Josh's question
• 29:24
  Speaker 1: about building a death star. But first let's take a
• 29:28
  Speaker 1: quick break, all right. So Josh from Fargo, North Dakota
• 29:44
  Speaker 1: has a question about building a death star, and I
• 29:49
  Speaker 1: have to say I kind of wonder why he's asking
• 29:51
  Speaker 1: this question. So here's Josh with his question. Hi, Daniel Horror. Hey,
• 29:56
  Speaker 1: this is Joshua Higginson from Fargo, and today my question
• 30:00
  Speaker 1: stion is, oh, could we build a death star? I've
• 30:06
  Speaker 1: been thinking about that question lately. I mean, are there
• 30:09
  Speaker 1: even enough resources on the planet to construct such a
• 30:12
  Speaker 1: massive advice? What kind of power would the death laser require?
• 30:18
  Speaker 1: And couldn't really make a planet explode? O? Man, I
• 30:20
  Speaker 1: love how he has music. He had music to this question. Yeah, Josh,
• 30:24
  Speaker 1: it's pretty awesome. I don't think Josh deserves having you
• 30:27
  Speaker 1: impugne his intentions. I think we should. I don't know Josh,
• 30:33
  Speaker 1: but he sounds awesome and I think we should assume
• 30:35
  Speaker 1: that his curiosity comes from the same place that all
• 30:38
  Speaker 1: the questions come from, which is just a desire to know.
• 30:41
  Speaker 1: I don't think Josh is out there wanting to build
• 30:43
  Speaker 1: a death star so he can blow up innocent planets,
• 30:45
  Speaker 1: right Josh. Um, that depends on what his last name is.
• 30:52
  Speaker 1: Maybe Josh Skywalker. And we should be worried a little bit.
• 30:57
  Speaker 1: What do you think about, you know, whether the Constitution
• 31:00
  Speaker 1: text people's rights to build their own death star? Is
• 31:02
  Speaker 1: that a well regulated militia, the right to bear giant satellite?
• 31:08
  Speaker 1: Um stays faring death rays? Hey, how else are you
• 31:12
  Speaker 1: going to protect against the tyrannical government? Right? Good guys
• 31:15
  Speaker 1: with death stars? That's the answer. What would have happened
• 31:21
  Speaker 1: if the Rebel Alliance had their own death star? Yeah?
• 31:24
  Speaker 1: Some people had the death star in their pockets. Um. So, yes,
• 31:28
  Speaker 1: that's an interesting question. And we're going to assume he's
• 31:31
  Speaker 1: just curious, he doesn't actually want to build one for
• 31:34
  Speaker 1: some reason. Um. I guess it's a pretty interesting question.
• 31:37
  Speaker 1: I guess it's like, is it even physically possible to
• 31:41
  Speaker 1: build one and maybe even have a one exist? I
• 31:45
  Speaker 1: guess is the question? Right? Yeah? And it's a great question,
• 31:48
  Speaker 1: and it comes in a long tradition of wonderful inspiration
• 31:51
  Speaker 1: for new technology from science fiction. You know, our science
• 31:55
  Speaker 1: fiction authors are always imagining what the future will be like,
• 31:57
  Speaker 1: how humans will live, and what kind of new gizmos
• 32:00
  Speaker 1: they might invent. And then scientists do this, they say
• 32:03
  Speaker 1: that does seem cool? Could I make that? And so
• 32:06
  Speaker 1: this is a wonderful, long tradition of following up on
• 32:09
  Speaker 1: the ideas of science fiction authors. And for those of
• 32:11
  Speaker 1: you who have not seen Star Wars, which I don't
• 32:14
  Speaker 1: know if it's possible, but in case, I've met a
• 32:17
  Speaker 1: lot of people who haven't seen Star Wars. To be honest,
• 32:19
  Speaker 1: I'm pretty sure the ven diagram of people who listen
• 32:22
  Speaker 1: to this podcast and people have seen Star Wars of
• 32:24
  Speaker 1: overlap well for the occasional outlier. The Death Star in
• 32:28
  Speaker 1: Star Wars was a giant it's it's a giant sphere
• 32:32
  Speaker 1: man made not a moon, right, not a moon, but
• 32:36
  Speaker 1: about the size of a moon. It was actually like
• 32:39
  Speaker 1: a giant space station, right, who's made entirely out of
• 32:43
  Speaker 1: metal that you can see, And it had a giant
• 32:47
  Speaker 1: death rate. It certainly did capable of destroying planets. And
• 32:51
  Speaker 1: so I guess the question is could you even build
• 32:53
  Speaker 1: such a thing? Wouldn't would it be hard to make?
• 32:55
  Speaker 1: Could you know? Would it collapse on its own? How?
• 32:58
  Speaker 1: How could you build it? How would you flight around?
• 33:01
  Speaker 1: Wouldn't it just get sucked into the orbit of other things?
• 33:04
  Speaker 1: And so that's the that's what will that's what will
• 33:06
  Speaker 1: be hopefully answering to me. And it's question. Apparently a
• 33:08
  Speaker 1: lot of people have Apparently a lot of people ask
• 33:11
  Speaker 1: Obama to build one. Yeah, you can write these petitions
• 33:14
  Speaker 1: to the White House there on the website, and any
• 33:16
  Speaker 1: petition that got more than twenty five thousand people to
• 33:18
  Speaker 1: sign on, the White House had to officially respond to
• 33:21
  Speaker 1: the petition. And so in two thousand and twelve thousand
• 33:25
  Speaker 1: people asked President Obama to build a death star, not
• 33:29
  Speaker 1: like hey, could you, but like, we want you to
• 33:31
  Speaker 1: do this. This should be a policy priority. The people's
• 33:35
  Speaker 1: the people's on the internets want I don't know how
• 33:39
  Speaker 1: many of those were actually Russian bots. Do you think
• 33:43
  Speaker 1: the Russians want Obama to build a death star? I
• 33:45
  Speaker 1: don't think so. Well, we have a space force, so
• 33:50
  Speaker 1: you know, we're not that far from a death star.
• 33:53
  Speaker 1: And so, of course the Obama White House did respond
• 33:56
  Speaker 1: as required by law, and they rejected this petition for
• 33:59
  Speaker 1: I think a pretty good Yeah, that's pretty awesome. They
• 34:01
  Speaker 1: said that such a death star would have a fundamental
• 34:04
  Speaker 1: design flaw because it can be destroyed by a single
• 34:08
  Speaker 1: small spacecraft by one farmer from the desert. Send it
• 34:13
  Speaker 1: back to the drawing board. Give me an impregnable death
• 34:16
  Speaker 1: start that one they would build, right, although if you
• 34:19
  Speaker 1: think about it, they did. They did it twice right
• 34:21
  Speaker 1: in Star Wars. It's like the first one got destroyed
• 34:24
  Speaker 1: by a single spacecraft, they build another one. They didn't
• 34:26
  Speaker 1: change the design. It was still vulnerable to a single spacecraft.
• 34:30
  Speaker 1: That's the problem with big government. You know, not very agile,
• 34:33
  Speaker 1: not very agile, but you know, say you wanted to
• 34:35
  Speaker 1: build this thing. And in the movies, you notice they
• 34:38
  Speaker 1: don't build it on on a planet, right, they build
• 34:40
  Speaker 1: it in space itself. They had these awesome scenes. You
• 34:43
  Speaker 1: can see the construction part way through in one of
• 34:45
  Speaker 1: the movies. Well, I think there's several questions here, is like,
• 34:48
  Speaker 1: how would you build it is even physically possible for
• 34:51
  Speaker 1: it to exist? And also that laser can we build
• 34:54
  Speaker 1: a laser like that? And also can we wear cool helmets?
• 34:58
  Speaker 1: Like these guys, where activate the license laser? I think
• 35:01
  Speaker 1: that's the only part that you can do actually to
• 35:03
  Speaker 1: cut the whole question short is where those cool helmets?
• 35:07
  Speaker 1: But it's a it's pretty awesome question. I think can
• 35:09
  Speaker 1: you build something that big? And there's a lot of
• 35:11
  Speaker 1: limitations there. One is just like can you find enough stuff?
• 35:15
  Speaker 1: You know, you want to build something the size of
• 35:16
  Speaker 1: the moon. The Moon is big, you know, the Moon
• 35:19
  Speaker 1: is like twenty five times all the mass of all
• 35:22
  Speaker 1: the asteroids and the asteroid belt. It's enormous times wow.
• 35:26
  Speaker 1: But it's solid. The Moon is solid. But the Death Star,
• 35:29
  Speaker 1: you know, had hallways and trash compactor rooms and hangars,
• 35:35
  Speaker 1: so it's not uh, it's it's not a solid piece
• 35:39
  Speaker 1: of steel. Right. Do you still need a lot? You
• 35:41
  Speaker 1: still need a lot and you know, but we do
• 35:43
  Speaker 1: have the resources. We have planets, We have small moons.
• 35:46
  Speaker 1: So you can imagine you could take some of the
• 35:48
  Speaker 1: stuff from the asteroid belt, and you could take some
• 35:50
  Speaker 1: small moons from some of the planets, and there are
• 35:53
  Speaker 1: the raw materials. They're like the asteroid belt in those
• 35:55
  Speaker 1: moons have a lot of metal. Oh I see, So
• 35:58
  Speaker 1: it's technically possible to build a structure structure like that. Well,
• 36:03
  Speaker 1: I'd say that these sources are out there, like they
• 36:05
  Speaker 1: just don't exist on Earth. Earth steel output every year
• 36:08
  Speaker 1: is pretty small, Like you need about eight hundred and
• 36:11
  Speaker 1: thirty thousand years of humanity's current output is steel to
• 36:15
  Speaker 1: have enough to build a death star. So that's going
• 36:18
  Speaker 1: to take a long time. So you need to find
• 36:19
  Speaker 1: it something, need to source it somewhere else. You need
• 36:21
  Speaker 1: to go to the asteroid steel steel yards, okay, and
• 36:24
  Speaker 1: that's where you could possibly build it. So you can't
• 36:28
  Speaker 1: build it from materials here on Earth. But if you
• 36:31
  Speaker 1: find those materials that in asteroids, you could technically build one. Yeah,
• 36:35
  Speaker 1: I think it'd be easier to get all that metal
• 36:36
  Speaker 1: out of asteroids rather than digging it out of the
• 36:38
  Speaker 1: Earth's crust. And somebody did a calculation like how much
• 36:42
  Speaker 1: would that steel cost? And they came up with a
• 36:44
  Speaker 1: ridiculous number, which is eight hundred and fifty quadrillion dollars
• 36:48
  Speaker 1: worth of steel. That doesn't sound too bad. Isn't that
• 36:50
  Speaker 1: about the the size of the U S deficit at
• 36:52
  Speaker 1: this point? Or that doesn't sound too bad to you? Hey, aorry,
• 36:55
  Speaker 1: can I borrow a hundred fifty thousand quadrillion dollars please,
• 36:59
  Speaker 1: it's just you know, for quarters, I'll take either one, honestly, no,
• 37:06
  Speaker 1: But of course that number is ridiculous because you had
• 37:08
  Speaker 1: that much steal, then it would change the price and
• 37:10
  Speaker 1: you know, dot dot dot economics. But the point is,
• 37:13
  Speaker 1: it's an enormous amount of resources. We don't have that
• 37:15
  Speaker 1: here in the surface of the Earth. You probably have
• 37:17
  Speaker 1: to take a part of Moon or all of the
• 37:19
  Speaker 1: asteroids or both just even get enough resources to build it.
• 37:23
  Speaker 1: But technically it is possible. Well, there's there's a structural
• 37:27
  Speaker 1: question also, you know that's like can you get enough steel?
• 37:30
  Speaker 1: But you put enough steel together and it has a
• 37:32
  Speaker 1: lot of gravitational attraction, you know, it weighs a lot. Yeah,
• 37:37
  Speaker 1: I was just pulling itself, Like, think about what prevents
• 37:40
  Speaker 1: you from building a steel tower that's like twenty miles high. Well,
• 37:45
  Speaker 1: the top of the tower is pressing on the bottom
• 37:46
  Speaker 1: of the tower, and the tower twenty miles high, and the
• 37:48
  Speaker 1: the twenty miles of steel pressing on the bottom, so
• 37:52
  Speaker 1: the bottom is going to get crushed. So if you're
• 37:54
  Speaker 1: gonna make a moon sized object, then it's going to
• 37:57
  Speaker 1: start to get its own gravity and it's gonna put
• 38:00
  Speaker 1: some stress on it. Oh man, let's not get into
• 38:02
  Speaker 1: gravity and star Wars, because I feel like we had
• 38:05
  Speaker 1: We can have a whole episode here about where do
• 38:08
  Speaker 1: these spaceships get gravity? And star Wars? Alright, So, assuming
• 38:12
  Speaker 1: we have perfect control of gravity, we can manipulate however
• 38:15
  Speaker 1: we like. Then let's ask a really detailed question about
• 38:17
  Speaker 1: construction of a death star. Yeah, assuming gravity, uh doesn't exist,
• 38:23
  Speaker 1: but producing in our universe right now, if you build
• 38:26
  Speaker 1: a giant structure of steel, it would probably collapse. It's
• 38:29
  Speaker 1: just so heavy on itself, right, it gets pretty thin. Yeah,
• 38:35
  Speaker 1: but I think it probably possible. Remember, gravity even on
• 38:37
  Speaker 1: the Moon is not that strong compared to gravity on
• 38:40
  Speaker 1: the surface of the Earth. So if you're out there
• 38:42
  Speaker 1: in space, there'd be some gravity just from its own attraction.
• 38:46
  Speaker 1: But I don't think it'd be a limiting factor. Oh,
• 38:48
  Speaker 1: I see, you could maybe like m oh, I see,
• 38:50
  Speaker 1: like a steel tower on Earth would collapse because it's
• 38:52
  Speaker 1: on Earth, but a steel tower out in space wouldn't
• 38:56
  Speaker 1: feel the same gravity to collapse. Yeah, you need need
• 38:59
  Speaker 1: to make this a start and be really enormous before
• 39:02
  Speaker 1: the gravitational forces would play a significant role and have
• 39:05
  Speaker 1: to have, you know, mass more than the moon in
• 39:08
  Speaker 1: order to have significant gravity. Well, that's why you would
• 39:11
  Speaker 1: really lean on your astro engineers precisely, precisely, and maybe
• 39:15
  Speaker 1: they come up with a better material. You know, maybe
• 39:17
  Speaker 1: steel is not the material of choice for building your
• 39:20
  Speaker 1: you know, intergalactic death bomb. Maybe you wanted out of
• 39:23
  Speaker 1: a different material, Yeah, aluminum or something else. I'm not sure.
• 39:26
  Speaker 1: All right, Well then, um, it seems like it's plausible.
• 39:29
  Speaker 1: There are resources out there and and there might be
• 39:33
  Speaker 1: a good way to engineer the structure like that. But
• 39:35
  Speaker 1: then I guess the question is can can I make
• 39:38
  Speaker 1: that laser the cool green laser that can destroy a planet?
• 39:44
  Speaker 1: And that's what it's really about, isn't that Everybody just
• 39:46
  Speaker 1: wants to build a really big gun. Well, do you think,
• 39:48
  Speaker 1: Josh this is the part Josh was interested in, or
• 39:50
  Speaker 1: was he interested in the astro engineering part of it?
• 39:53
  Speaker 1: I don't know. I wonder if Josh has a laser
• 39:55
  Speaker 1: in his garage and these building and he's wondering, like
• 39:58
  Speaker 1: how big could I make this thing? He's like, I
• 40:01
  Speaker 1: can't get it big enough. I'll ask Daniel Horror. Maybe
• 40:04
  Speaker 1: they can chime in, Maybe they can help me destroy
• 40:07
  Speaker 1: the universe instead of explained it. Um. Well, currently we
• 40:11
  Speaker 1: have some pretty powerful lasers, but they're not anything close
• 40:14
  Speaker 1: to what you would need in order to destroy a planet.
• 40:17
  Speaker 1: Like currently, our lasers can just barely deflect a missile,
• 40:21
  Speaker 1: you know, or shoot down an incoming missile, and there
• 40:23
  Speaker 1: are people working on lasers that might be able to
• 40:25
  Speaker 1: deflect an asteroid. But the most powerful laser we have
• 40:28
  Speaker 1: right now is like two petal wats. Sounds like a lot,
• 40:31
  Speaker 1: but you know, like a light bulb is sixty watts.
• 40:36
  Speaker 1: A petal wat sounds like a lot of zeros. Petat
• 40:39
  Speaker 1: is a lot of zeros, but it takes even more
• 40:41
  Speaker 1: zeros to blow up a planet. Somebody again, did this calculation.
• 40:45
  Speaker 1: Somebody in astro engineering program, I guess, and they calculated
• 40:48
  Speaker 1: that you would need a million billion of two of
• 40:52
  Speaker 1: the two most powerful lasers on Earth in order to
• 40:55
  Speaker 1: sort of damage a planet enough to break it up.
• 40:58
  Speaker 1: Somebody actually calculated this, Like, here's a formula for destroying
• 41:02
  Speaker 1: a planet. This is something in people's minds. You know,
• 41:06
  Speaker 1: you see something on TV, your scientists, you think, could
• 41:09
  Speaker 1: we actually do that? And then you get out a
• 41:11
  Speaker 1: piece of paper and a pencil and you try to
• 41:12
  Speaker 1: figure it out, and you're like, I have tenure, I
• 41:14
  Speaker 1: can do it. I can spend my day doing this.
• 41:17
  Speaker 1: There's probably a journal of death Star engineering that you
• 41:19
  Speaker 1: could publish these papers, and there you go. Aster the
• 41:22
  Speaker 1: Journal of astro Genocide is a phrase I've never heard
• 41:27
  Speaker 1: before and instantly hate astrogenocide. But do you so you
• 41:30
  Speaker 1: need a million billion of the most powerful lasers currently
• 41:35
  Speaker 1: on Earth to make it? But maybe that sounds not implausible.
• 41:40
  Speaker 1: I mean, if we're going to build a death Star
• 41:42
  Speaker 1: and spend eight hundred and fifty quadrillion dollars, why not
• 41:45
  Speaker 1: build a million billion powerful lasers? Yeah? I mean if
• 41:48
  Speaker 1: you have infinite resources and time and money, if you
• 41:50
  Speaker 1: become emperor or the Earth and this is what you
• 41:53
  Speaker 1: wanted to devote all of humanities resources too, it's not
• 41:56
  Speaker 1: totally implausible. But there is one thing about the laser
• 41:59
  Speaker 1: in movie that I think we could never accomplish. Did
• 42:02
  Speaker 1: the green color or oh, we could do whatever color
• 42:05
  Speaker 1: you like? But you know how when they pull the lever,
• 42:08
  Speaker 1: they have this really cool effect where the lasers come
• 42:10
  Speaker 1: out from the edge of the circle, meet in the middle,
• 42:13
  Speaker 1: glow for a minute, and then zap off. Right, that's impossible.
• 42:17
  Speaker 1: Lasers don't do that. They don't like meet and converge
• 42:20
  Speaker 1: and then zoom off. They just sort of shooting a
• 42:22
  Speaker 1: straight line. So it's not as cool looking from the
• 42:25
  Speaker 1: in a cinematic point of view. But you need a
• 42:27
  Speaker 1: single Lasers just sort of shot out of the edge
• 42:30
  Speaker 1: of a muzzle. They don't like come together and converge
• 42:33
  Speaker 1: that way and then change direction in mid space. Oh,
• 42:35
  Speaker 1: I see, it's like, yeah, it was that in the movie.
• 42:39
  Speaker 1: They it's like four or five individual beams that come
• 42:43
  Speaker 1: together and then shoot out to the to the planet
• 42:46
  Speaker 1: to destroy it. That's the part that's unnatural or physically impossible.
• 42:50
  Speaker 1: That's right. But hey, if you want to build your
• 42:52
  Speaker 1: own iron Moon and just shoot out a normal, boring
• 42:55
  Speaker 1: laser to Detroit planets, then I think that is possible. Okay,
• 42:59
  Speaker 1: that gets your ruble. I guess that's in the ridiculous,
• 43:04
  Speaker 1: huge waste of money but potentially possible category. Well, here's
• 43:08
  Speaker 1: a question for you, Daniel, how do you know that
• 43:10
  Speaker 1: the Death Star used lasers? You're right, it could have
• 43:14
  Speaker 1: been you know, projections of the force or some other
• 43:17
  Speaker 1: sort of like weird plasma thing. I'm not sure they
• 43:21
  Speaker 1: technically call it a laser, right or anything. It's just
• 43:25
  Speaker 1: a weapon, that's true. Um, what do they call it?
• 43:29
  Speaker 1: They call it the energy beam. Now we need another
• 43:31
  Speaker 1: excuse to go back and watch that movie. I'm sure
• 43:35
  Speaker 1: we can just post a question online and a few
• 43:39
  Speaker 1: people who have maybe seen the movie a few times,
• 43:42
  Speaker 1: some astro engineering experts. So well, I guess I'm just saying,
• 43:45
  Speaker 1: we don't know they're lasers. Maybe it's something else that
• 43:48
  Speaker 1: could potentially, um have that cool effect. That's true. And
• 43:52
  Speaker 1: if you're gonna be in another science fiction universe where
• 43:54
  Speaker 1: the laws of physics are different and weird magical ancient
• 43:57
  Speaker 1: religions are real, then hey, maybe you can do anything
• 44:00
  Speaker 1: you like. Well, it seems like the answer for Josh
• 44:02
  Speaker 1: here is that it is. Yes, we could maybe build
• 44:05
  Speaker 1: a death star. It would just take a lot of
• 44:07
  Speaker 1: resources and a little bit of money. Yeah, So don't
• 44:11
  Speaker 1: stop working on that project in your garage, Josh, it
• 44:13
  Speaker 1: will work out or no, please please do stop if
• 44:18
  Speaker 1: you're trying to build a laser that destroys the earth. Please.
• 44:21
  Speaker 1: I'm assuming Josh is going to be a good guy
• 44:23
  Speaker 1: with a death star. Oh, I see he's pointing at
• 44:25
  Speaker 1: Outwards and all the bad guys with death stars. All right,
• 44:29
  Speaker 1: So those were two great questions. Thank you to Josh
• 44:32
  Speaker 1: and to Glenn for submitting their questions to us via
• 44:36
  Speaker 1: Twitter and email, and those of you listening, if you
• 44:39
  Speaker 1: have a question that you would like to answer to,
• 44:43
  Speaker 1: Daniel will read your email and your messages and we
• 44:45
  Speaker 1: might even answer it on the podcast. And you don't
• 44:49
  Speaker 1: even need to shoot us with your death star or
• 44:51
  Speaker 1: give us any baby black holes. But thank you everybody
• 44:55
  Speaker 1: for continuing to send in your questions. They're wonderful, they're stimulating,
• 44:58
  Speaker 1: there a lot of fun, and we love an ring
• 45:00
  Speaker 1: them here on the podcast. Yeah, keep asking questions. See
• 45:03
  Speaker 1: you next time. Thanks for tuning in. Before you still
• 45:13
  Speaker 1: have a question after listening to all these explanations, please
• 45:16
  Speaker 1: drop us a line. We'd love to hear from you.
• 45:19
  Speaker 1: You can find us on Facebook, Twitter, and Instagram at
• 45:22
  Speaker 1: Daniel and Jorge That's one word, or email us at
• 45:25
  Speaker 1: Feedback at Daniel and Jorge dot com. Thanks for listening,
• 45:29
  Speaker 1: and remember that Daniel and Jorge Explain the Universe is
• 45:32
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• 45:38
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