Speaker 1: Hey or hey, are you a fan of Pokemon cards? Yeah,
Speaker 1: a little bit. My son used to play them. My
Speaker 1: son also, though I think he mostly collected and traded them.
Speaker 1: I don't think he ever actually played with them. M Yeah,
Speaker 1: I think that happens a lot, although I did play
Speaker 1: with him for a few times. It's a pretty interesting game.
Speaker 1: And do you have any of those cards with like
Speaker 1: super awesome powers? Yeah? They have pretty good names, like
Speaker 1: flame body. My personal favorite is the card that can
Speaker 1: do a black hole eclipse. Although that sounds kind of
Speaker 1: like a random combination of words from physics that they
Speaker 1: just kind of put together. I think that's the same
Speaker 1: way that physicist name things though. Ah, so you admitted
Speaker 1: it's all random. We just type the words into an
Speaker 1: online random number generator and that's where we go with.
Speaker 1: They have a bunch of physicists working for Pokemon, just
Speaker 1: in case that the whole physics scurity doesn't work out.
Speaker 1: Do you have a promising career working for That's always
Speaker 1: been my backup plane. Hi am Poor Hamming, cartoonist and
Speaker 1: the co author of Frequently Asked Questions about the Universe. Hi.
Speaker 1: I'm Daniel. I'm a particle physicist and a professor at
Speaker 1: UC Irvine, and I probably have hundreds of dollars worth
Speaker 1: of Pokemon cards somewhere in the closets of my home.
Speaker 1: Are they wrapped an individual plastic though, to keep him
Speaker 1: in mint condition? Otherwise I'm not sure they're worth that much.
Speaker 1: They have definitely been prepared as an investment in the future.
Speaker 1: That's how you plan to pay for your son's college education.
Speaker 1: I think that's how my son plans to pay for
Speaker 1: his retirement. Yeah. Wow, if it's worth that much, maybe
Speaker 1: they should conveniently disappear from your closet. Only if I
Speaker 1: could find them in my son's closet. I think that's
Speaker 1: part of his security plan. Yes, it's such a mess,
Speaker 1: it's like a black hole in itself, but anyway is
Speaker 1: Welcome to our podcast Daniel and Jorge Explain the Universe,
Speaker 1: a production of I Heart Radio in which we try
Speaker 1: to clean up a mess that is this universe and
Speaker 1: all of its crazy, confusing glory. We dig right into
Speaker 1: everything that doesn't make sense, everything that should make sense,
Speaker 1: and things that might never make sense. We talked about
Speaker 1: the biggest questions at the heart of philosophical inquiries about
Speaker 1: the nature of our universe, and we talk about practical
Speaker 1: stuff like how things around you actually work. We dive
Speaker 1: into all of these questions and try to explain to
Speaker 1: you what scientists do and do not know about them
Speaker 1: because it is a pretty fun universe full of interesting
Speaker 1: and amazing characters, not all of them with superpowers like
Speaker 1: Pokemon characters, but there are a lot of interesting objects
Speaker 1: out there in the universe with the seemingly superpowerful powers.
Speaker 1: And it is our belief, or at least our hope,
Speaker 1: that the universe does make sense, that it's following some
Speaker 1: set of rules, and that if we dig into it
Speaker 1: hard enough, if we use our brains, if we come
Speaker 1: up with a clever set of experiments, we can figure
Speaker 1: out what those rules are. That in the end, there
Speaker 1: isn't magic in the universe, but that everything can be
Speaker 1: explained with science. I'm not sure the same can be
Speaker 1: said about Pokemon powers. What are you saying that Pokemon
Speaker 1: aren't physically accurate there? How do you know, Daniel, I'm
Speaker 1: not sure we have to suspend disbelief. But I did
Speaker 1: do a bit of research into what the black hole
Speaker 1: eclipse move is for the Pokemon character, and here's the
Speaker 1: official description. The user gathers dark energy with its Z
Speaker 1: power and forms a black hole that sucks the opponent up. Interesting.
Speaker 1: That seems like a bit of a dangerous weapon there,
Speaker 1: because once you start the black hole, I guess, can
Speaker 1: you turn it off? Or is there a Z switch
Speaker 1: for it? It depends on what your Z power can do.
Speaker 1: If you can tap into dark energy and expand or
Speaker 1: contract space, then hey, you have got a lot of options. Well,
Speaker 1: there is the idea that maybe there are unknown forces
Speaker 1: in the universe we haven't discovered. Maybe the Z force
Speaker 1: is one of them. And if I discovered an unknown
Speaker 1: force and called it the Z force, would you be
Speaker 1: impress with my naming? I guess I mean to try
Speaker 1: out any of the other letters in the alphabet first.
Speaker 1: The Z force makes me think it's related to the
Speaker 1: Z boson, which we know is a very feeble boson.
Speaker 1: It carries the weak force, probably not capable of making
Speaker 1: black holes. So there is technically a Z force in
Speaker 1: the universe right now, like the force made by a
Speaker 1: Z boson is technically a Z force. Yeah, that's right,
Speaker 1: though I'm not sure you can use it to gather
Speaker 1: any dark energy and throw your opponent into a black hole.
Speaker 1: But hey, best to luck to you. How do you know, Daniel,
Speaker 1: have you tried? I haven't tried, but I'm going to
Speaker 1: write a grand proposal to the Pokemon Science Foundation to
Speaker 1: see if I can get some funds to try it out. Yeah,
Speaker 1: the PSF, they fund a lot of work out here.
Speaker 1: But technically, in a multiverse, isn't it possible that there
Speaker 1: are Pokemon characters out there? I mean, if you say
Speaker 1: in a multiverse, isn't it possible that I suppose almost
Speaker 1: anything is possible because in some theories of the multiverse
Speaker 1: there are universes with other laws of physics, which basically
Speaker 1: allows almost anything to happen. Oh, there you go, It's official.
Speaker 1: Here in the podcast, Daniel thinks Pokemon are real. They
Speaker 1: are a really good investment in my son's feature and
Speaker 1: a real possibility. But it is interesting. How did you
Speaker 1: end up googling Pokemon powers online? What's going on there? Daniel? No,
Speaker 1: I was googling black hole eclipse, of course, in preparation
Speaker 1: for today's episode. And the top hit was not black
Speaker 1: holes or eclipses or anything scientific. The top like ten
Speaker 1: hits were all about Pokemon. I think that tells you
Speaker 1: a little bit about the priority of the Internet. But
Speaker 1: it is interesting. What do you think is going on
Speaker 1: inside the head of those Pokemon creators, artists and writers
Speaker 1: when they come up with these things, Right, because they
Speaker 1: used to work dark energy, they must know a little
Speaker 1: bit of something about physics. Well, you know, I think
Speaker 1: as they make more and more Pokemon characters, that have
Speaker 1: to be more and more powerful or as my son
Speaker 1: would say, totally opie, and so they want to come
Speaker 1: up with something really dramatics and they're really crazy. And
Speaker 1: I guess black holes are on the top of the
Speaker 1: list of like aspirational powers to whether you can make
Speaker 1: a black hole using dark energy. You know, we don't
Speaker 1: really know what dark energy is at all. We just
Speaker 1: know that it's accelerating the expansion of space and separating
Speaker 1: the black holes from each other. So if anything, it's
Speaker 1: keeping black holes from getting bigger. Well, I guess my
Speaker 1: question is what kind of energy car does that attack us?
Speaker 1: Dark energy cars? Is there such a thing? If there
Speaker 1: isn't such a thing, then there should be Pokemon Science Foundation,
Speaker 1: please fund that. There should be a science type Pokemon.
Speaker 1: You know, there's like a water type, fire type. There
Speaker 1: should be like a physics type. We have exhausted my
Speaker 1: knowledge of Pokemon. Now I have nothing else to contribute
Speaker 1: to this conversation. I went a little opie on you
Speaker 1: all overpowered you. But it is an interesting name to
Speaker 1: give a power to a fictional character. But it kind
Speaker 1: of makes you think, is it actually possible for something
Speaker 1: like that to happen? And we know that crazy things
Speaker 1: happen out there in the universe. We are constantly surprised
Speaker 1: by what's going on in the hearts of other galaxies
Speaker 1: and even in between galaxies, and so you should never
Speaker 1: say never, and so do they. On the podcast, we'll
Speaker 1: be asking the question can a black hole be eclipsed?
Speaker 1: And can you use it to suck up your enemies?
Speaker 1: Is the question that a lot of kids are probably asking,
Speaker 1: and maybe some physicists. Please, if you do have the
Speaker 1: z power to manipulate dark energy to create black holes,
Speaker 1: don't do it. You might win the battle and then
Speaker 1: destroy the planet. Although they'll give you a Nobel prize, though,
Speaker 1: wouldn't they in the five minutes between the creation of
Speaker 1: your black hole and the destruction of the Earth. I'm
Speaker 1: not sure the Swedish Academy acts that fast. I don't know.
Speaker 1: I've seen you talk, Daniel, you will sacrifice anything for science.
Speaker 1: If you have such a Z power, create a black
Speaker 1: hole out in the depths of space where we can
Speaker 1: study it. Please. I guess if you have that kind
Speaker 1: of power, you can afford to go out into space. Right.
Speaker 1: Maybe you also have the ex power and the why power?
Speaker 1: Right right? Although I thought the why power was physicist
Speaker 1: superpower or is that the philosophers? It's the four year
Speaker 1: olds power? Why? Why? Why? Why? Yes, it's an interminable
Speaker 1: source of energy. But it is an interesting question, and
Speaker 1: as usual, we were wondering how many people out there
Speaker 1: had thought about this question whether a black hole can
Speaker 1: be eclipsed. So thanks very much to everybody who volunteers
Speaker 1: to answer these questions in advance. Were very grateful to you,
Speaker 1: and we hope that you enjoy hearing your voice on
Speaker 1: the podcast. If any of you out there would like
Speaker 1: to participate, please don't be shy. Right to me two
Speaker 1: questions at Daniel and Jorne dot com. So think about
Speaker 1: it for a second. Do you think a black hole
Speaker 1: can be eclipsed? Here's what people had to say. Assuming
Speaker 1: the definition of eclipse is for one body to obscure
Speaker 1: another body from a given a vantage point. Um sure,
Speaker 1: I don't see why a black hole could not be
Speaker 1: eclipsed by another celestial body. I thought that might be
Speaker 1: how we discovered them or something. I guess a black
Speaker 1: hole can be eclipsed. I mean normally in eclipse is
Speaker 1: when the light from something is blocked by something else
Speaker 1: in space. So as a black hole doesn't have any
Speaker 1: light emitting from it, I wouldn't have thought it could
Speaker 1: be eclipsed as such. But I guess if you get
Speaker 1: something massive enough in front of it, in between us
Speaker 1: and it, then it would be eclipsed. I don't see
Speaker 1: why not. As long as something subjectively larger than them
Speaker 1: is between them and the observer, it would eclipse. The
Speaker 1: black hole might have to be subjectively larger than the
Speaker 1: disc around it to really have a shot at it. Well,
Speaker 1: the concept of eclipse, the way I understand it, is
Speaker 1: that light from a star as blocked from Earth's view
Speaker 1: by an intervening body. Certain's black holes do not emit light.
Speaker 1: I don't think they can be eclipsed. I don't think
Speaker 1: so because I believe when black holes mass passes before
Speaker 1: a gravity you see lensing effects. And I don't know
Speaker 1: I've ever heard of one being eclipsed before. Yes, I
Speaker 1: think they can do if they're is a planet or
Speaker 1: star closer to us in the right alignment with the
Speaker 1: black hole. Yes, I think they can be eclipsed. Yes,
Speaker 1: I think it can in the sense that is coming
Speaker 1: in front of something else. Um. But like instead of
Speaker 1: blocking the light like the moon we block the Sun's light,
Speaker 1: I think it would just absorb the light of whatever
Speaker 1: is behind it. But um, it could also have this
Speaker 1: gravitational lensing effect where the light of the objects that
Speaker 1: aren't directly behind it kind of get curved um due
Speaker 1: to the black hole, and we perceive it um in
Speaker 1: that way. So that's kind of the black hole version
Speaker 1: of an eclipse. Yes, they can be eclips Let's say
Speaker 1: instead of our son, it will be a black hole
Speaker 1: like we heard at a podcast Danielle and Horhan. We
Speaker 1: would need to be at a safe distance from it,
Speaker 1: and we can safely go around it. And if we
Speaker 1: have the moon that would be between us and the
Speaker 1: that hole. I don't see why not the more collectives
Speaker 1: the site of the black hole. All right, A wide
Speaker 1: range of answers here. Somebody said, why not always a
Speaker 1: good answer? Am I talking about physics of the universe.
Speaker 1: Why not, there's the multiverse, Doctor Strange says, anything can
Speaker 1: happen in the multiverse. Or do you think they were
Speaker 1: taking it as a proposal, like, hey, should we make
Speaker 1: a black hole eclipse? Why not? Let's go right now.
Speaker 1: I'm up for it. I guess it made me think,
Speaker 1: what do you mean by eclipse, like in terms of
Speaker 1: attention or in terms of blocking its light? But it's
Speaker 1: a black hole. Yeah, it's a good question. And I
Speaker 1: noticed that there was like two different interpretations of eclipse there,
Speaker 1: one the black hole being eclipsed like something blocking light
Speaker 1: from a black hole, and the other the black hole
Speaker 1: doing the eclipsing, like passing in front of something else
Speaker 1: that makes light. So there's sort of two possibilities there. Interesting,
Speaker 1: and I guess we're going to argue about which one
Speaker 1: is more correct. For the next hour, we're going to
Speaker 1: talk about both possibility. At least. Of course, we're gonna
Speaker 1: do the quantum superposition. We're gonna do the forwards and
Speaker 1: the backwards. All right, Well, let's start with the basics here, Daniel,
Speaker 1: What is a black hole? First of all, so we
Speaker 1: don't really know what a black hole is in the
Speaker 1: actual universe, and we don't actually even really know if
Speaker 1: black holes exist. As described by the theory, we have
Speaker 1: this concept in general relativity that if you get enough
Speaker 1: stuff together, it's gravity will overcome any sort of internal strength,
Speaker 1: any power of the material to resist being compressed. The
Speaker 1: gravity will eventually get so strong that it will just
Speaker 1: squeeze it down further and further and further, and as
Speaker 1: it gets denser and denser, and the gravity gets stronger
Speaker 1: and stronger, and you get this crazy runaway effect, and
Speaker 1: where gravity essentially becomes infinitely strong in a tiny little dot,
Speaker 1: this singularity at the point in space where you have
Speaker 1: not infinite mass but infinite density, because gravity is compressed
Speaker 1: some blob of stuff down to a very very small distance,
Speaker 1: and because it's compressed it so far and means that
Speaker 1: you can get pretty close to a lot of mass,
Speaker 1: which means the gravity even nearby it would be very strong,
Speaker 1: so strong that we think that it curves space so
Speaker 1: much that light cannot even escape it. So if these
Speaker 1: things are real, if they're out there in the universe,
Speaker 1: then whatever falls into this black hole you will never
Speaker 1: see again because light from it cannot escape. Would you
Speaker 1: say it's an actual hole in space, Daniel. And you know,
Speaker 1: if you define a hole is something that you can
Speaker 1: fall into, then it's technically it is. That's why it's
Speaker 1: called a whole. Right, if you accept the general relativity
Speaker 1: view of it, it's kind of a hole because it
Speaker 1: makes a portion of space that's cut off from the
Speaker 1: rest of the universe. It's like a little sub universe,
Speaker 1: and once you enter that sub universe, you really are
Speaker 1: cut off from the rest of it. I mean inside
Speaker 1: the black hole, you can still see the rest of
Speaker 1: the universe. Light from the rest of the universe can
Speaker 1: still reach you, so you can see out from it,
Speaker 1: but nobody can see into it, right, So in that sense,
Speaker 1: it's a hole in space, right, Although that's assuming your
Speaker 1: eyeball is still in one piece when you're inside of
Speaker 1: a black hole, right, Yeah, precisely, assuming that you survive
Speaker 1: long enough to look out into the black hole. And
Speaker 1: black holes can come in all sorts of sizes. You
Speaker 1: can make a black hole in theory out of a
Speaker 1: pretty small amount of mass as long as you squeeze
Speaker 1: it down to a small enough radius. You can also
Speaker 1: make black holes out of enormous masses. Some of the
Speaker 1: things out there that we think are black holes probably
Speaker 1: have millions or billion times the mass of our sun.
Speaker 1: Those black holes are really really big, and if you
Speaker 1: fall into one of those, the gravity at the outskirts
Speaker 1: of the black hole is not actually that strong. I mean,
Speaker 1: it's strong enough to suck up light, but it's not
Speaker 1: so strong to like tear you apart to spaghettify you.
Speaker 1: So you might be able to survive the very first
Speaker 1: few moments of falling into a really really big black hole,
Speaker 1: and then you can take it selfie, although you can
Speaker 1: never send that selfie to anyone. Hey, selfies are just
Speaker 1: for yourself, right, that's why they're called selfie. Ironically, that
Speaker 1: is the opposite purpose of a selfie. They should be
Speaker 1: called that everyone else's. But it is interesting what you
Speaker 1: said about the black holes having a size, because it's
Speaker 1: it's kind of into it's like a hole in space,
Speaker 1: but it does have volume, right, Like, it does occupy
Speaker 1: three dimensional space. In fact, it's a sphere in space, right,
Speaker 1: I mean, it's just kind of distort space, but it
Speaker 1: does sort of occupy a certain you know, length, width
Speaker 1: and in height. Yeah, if you say black hole, you're
Speaker 1: probably imagining like a circle on the ground a two
Speaker 1: dimensional object that things can fall into and disappear, like
Speaker 1: in cartoon shows. But as you say, they are three
Speaker 1: dimensional objects. So the simplest black hole, one that isn't spinning,
Speaker 1: would be a perfect sphere, and you can fall into
Speaker 1: it from any direction. If you're looking at a perfect
Speaker 1: sphere that's perfectly black, it's always just gonna look like
Speaker 1: a circle to you because there's no texture to it,
Speaker 1: so you can't sort of like tell how much curvature
Speaker 1: it has. But actually, if you look at a black hole,
Speaker 1: you don't even really just see a black sphere. It
Speaker 1: looks even bigger than it actually is because the paths
Speaker 1: of light around the black hole are really really weird.
Speaker 1: Like if somebody was very close to the edge of
Speaker 1: the black hole on the back side of it and
Speaker 1: turned on a flashlight, you could see it from the
Speaker 1: other side of the black hole because the light from
Speaker 1: that flashlight would curve around the black hole, bent by
Speaker 1: its incredible gravity to your eyeballs. So if you're near
Speaker 1: a black hole, if you're just looking at it, you
Speaker 1: can actually see the entire surface of the black hole
Speaker 1: right in front of you. You can see the front
Speaker 1: and the back right though it just looks black, right, Yeah,
Speaker 1: it just looks like a bigger black circle than it
Speaker 1: actually is. It's like puffed up, yeah, like puffed up
Speaker 1: because in the vicinity of a black hole, space is curved,
Speaker 1: and when space is curved, you can't trust your eyes
Speaker 1: to be just showing you what he's there. You're seeing
Speaker 1: now an image of what is there, and then image
Speaker 1: can be distorted, just like if you're in a fun
Speaker 1: house mirror and it's not flat and what you're seeing
Speaker 1: isn't reality the same as true. Near a black hole,
Speaker 1: light doesn't travel in straight lines anymore, and so what
Speaker 1: you see is an image is generated by the physical
Speaker 1: stuff that's there, but it's not a fully faithful image
Speaker 1: of what's actually out there. It's a little bit mind
Speaker 1: bending because a black hole is sort of like a sphere.
Speaker 1: It sort of has the surface, but it's not really
Speaker 1: a surface because it's not solid. It's just kind of
Speaker 1: like the edge of the hole. So it's like a
Speaker 1: three dimensional edge of a hole is the surface of
Speaker 1: a black hole. Yeah, And what you call the edge
Speaker 1: of a black hole is a little bit arbitrary. We
Speaker 1: usually use the location of the event horizon, the point
Speaker 1: past which light and particles and nothing can escape, and
Speaker 1: to mark the edge of the black hole. But there's
Speaker 1: nothing there at the edge. It's sort of like a
Speaker 1: calculation we do to say where it is, and you
Speaker 1: can't actually even tell where the event horizon is until
Speaker 1: the end of the universe. The definition of the event
Speaker 1: horizon is any particle past this point never escapes. But
Speaker 1: it's not always easy to tell exactly what can escape
Speaker 1: and what can't, and so you can't actually know in
Speaker 1: any moment where the event horizon is. You have to
Speaker 1: sort of like wait to the end of time and
Speaker 1: then say, particles that got closer than this, none of
Speaker 1: them escaped. So here was the event horizon, right, because
Speaker 1: we actually like fall into the hole that sort of
Speaker 1: almost sort of never happens, right, because time gets distorted
Speaker 1: around the black hole that it basically as you said,
Speaker 1: happens never. Yeah. And also there's just like nothing there
Speaker 1: at the event horizon. It's not like a surface you
Speaker 1: land on. It's just a point of no return. It's
Speaker 1: like if you got into your car and you drove
Speaker 1: too far away from a gas station so that you
Speaker 1: didn't have enough gas to get to the next gas station.
Speaker 1: Nothing would happen at that moment when you had gone
Speaker 1: too far. You would only realize it later, like, oops,
Speaker 1: we forgot to get gas and now we're stranded. The
Speaker 1: moment when you crossed that threshold where you now too
Speaker 1: far away from the nearest gas station you don't have
Speaker 1: enough fuel to get one, no warning light necessarily goes off.
Speaker 1: And the same is true for the event horizon. It
Speaker 1: just feels like the rest of space. You pass through it,
Speaker 1: and unbeknownst to you, you are now wrapped inside the
Speaker 1: black hole. Right, Although you know, if you're flying that
Speaker 1: close to a black hole, you can't claim not to
Speaker 1: have seen it because it's going to look pretty big
Speaker 1: to flying close to a black hole. Right. Oh yeah,
Speaker 1: it's definitely irresponsible space flight in the same way like
Speaker 1: you should know if you're about to run out of gas,
Speaker 1: and somebody should be paying attention to it, or at
Speaker 1: least there should be a warning alarm on your space ship.
Speaker 1: Black hole ahead, turn right, use your Z powers now.
Speaker 1: But as you said, it doesn't occupy space because it
Speaker 1: is an object. It doesn't have less solid surface, and
Speaker 1: it's also like moving around in space, right, black holes
Speaker 1: can move around in space. Even though their holes in space,
Speaker 1: they can move around in space. It's like a moving hole. Yeah,
Speaker 1: well they are a thing, right, They are made out
Speaker 1: of mass, and so like everything else, they have a location,
Speaker 1: and then they can have a velocity. But you know,
Speaker 1: the velocity of the black hole is relative, just like
Speaker 1: everything else. If you are moving towards a black hole,
Speaker 1: you could also say the black hole is moving towards you.
Speaker 1: There is no difference in the physics of the universe
Speaker 1: in those two pictures, and so black holes, like everything else,
Speaker 1: can have location and velocity. Yeah, there could be one
Speaker 1: moving towards us right now, right almost definitely, because we
Speaker 1: know that there's a supermassive black hole at the heart
Speaker 1: of the Andromeda Galaxy which is coming for us. Right
Speaker 1: The Andromeda Galaxy is going to collide with the Milky
Speaker 1: Way in a few billion years, and so the black
Speaker 1: holes at the heart of each galaxy are moving towards
Speaker 1: the other galaxy. So, yeah, black holes are headed our way.
Speaker 1: Better get working on that Z force, Daniel. We're counting
Speaker 1: on you. I only have the P force, the physics force.
Speaker 1: Other people have to work on the Z force, or
Speaker 1: it could be the W force. For whites and there
Speaker 1: you go. I guess the the Andromeda black hole. That's
Speaker 1: something we don't want to catch alther if you find
Speaker 1: a good container for it. I guess, yeah, maybe you do.
Speaker 1: All right, well, let's talk about whether or not a
Speaker 1: black hole can be involved in an eclipse, whether it
Speaker 1: can eclipse other things, or whether you can eclipse a
Speaker 1: black hole. But first let's take a quick break. All right,
Speaker 1: we're talking about the physics of Pokemon, right, that's the
Speaker 1: title of the episode. That's right, Pokemon characters use physics
Speaker 1: on each other. I feel like that would be a
Speaker 1: pretty viral title to put on this episode. What do
Speaker 1: you think, physics of Pokemon? It might be viral. It
Speaker 1: would also be totally misleading, but I guess that's how
Speaker 1: everything goes viral. But we could do a whole episode
Speaker 1: on this, right, just pick a bunch of Pokemon cars
Speaker 1: and we'll break down the physics of their superpowers. Yeah,
Speaker 1: le's good like this. Yeah that's totally made up. Yeah
Speaker 1: that doesn't where Yeah that's ridiculous, But could it happened?
Speaker 1: Aren't there books about the physics of Star Trek and
Speaker 1: Star Wars in a multiverse where Pokemon is real, But
Speaker 1: we are talking about the powers of one specific Pokemon.
Speaker 1: Which Pokemon has this power? Daniel did, did you look
Speaker 1: up the name? Well, according to my research, it says
Speaker 1: any non mega evolved non primal Pokemon can use black
Speaker 1: hole eclipse if it knows a damaging dark type move
Speaker 1: and holds darkinium z and if it's trainer where's a
Speaker 1: z ring? So if that made sense to you, please
Speaker 1: explain it to me. Well, that's a lot of preconditions there,
Speaker 1: so any Pokemon that checks those boxes can use it. Yeah,
Speaker 1: apparently any non mega evolved non primal Pokemon. I don't
Speaker 1: know if there's a lot of them or just one.
Speaker 1: We we should you should have interviewed an expert. But anyways,
Speaker 1: we're asking the question of whether or not you can
Speaker 1: actually eclipse a black hole or I guess involved a
Speaker 1: black hole in an eclipse. And you said, Daniels, there's
Speaker 1: two possibilities here. You can either eclipse a black hole
Speaker 1: or have the black hole eclipse something else. And so
Speaker 1: I guess, first of all, Daniel, what's the legal definition
Speaker 1: of an eclipse? So an eclipse is a fun astronomical
Speaker 1: situation where two things fall along the same line, your
Speaker 1: line of sight. So you're looking out into the universe
Speaker 1: and you can imagine a line between your eyeball and
Speaker 1: some object. If something else passes along that line, then
Speaker 1: it has eclipsed whatever you were looking at. So if
Speaker 1: you're looking at the Sun not recommended, and the Moon
Speaker 1: passes in front of it, then that's a solar eclipse. Right.
Speaker 1: The moon is eclipsing the Sun because it's passing along
Speaker 1: the line between your eyeball and the Sun. Interesting, so
Speaker 1: if a technically, if I put my thumb in front
Speaker 1: of me and block out the Sun, I'm creating a
Speaker 1: solar eclipse. That's what you're saying. Yeah, I mean your
Speaker 1: thumb is not an astronomical object. Have you seen my sun?
Speaker 1: It's pretty stiller. It's been a while, So assuming you've
Speaker 1: upgraded it with your Z powers, than maybe or his
Speaker 1: them can perform in eclipse. One of my favorite things
Speaker 1: though about solar eclipses is that they're possible. Right, Like,
Speaker 1: the moon can block the Sun in the sky, which
Speaker 1: requires not just that the Moon goes in front of
Speaker 1: the Sun, but that the Moon is the same size
Speaker 1: or bigger than the Sun in the sky. The amazing
Speaker 1: thing is that the Moon and the Sun are just
Speaker 1: about the same size in our sky, like they can
Speaker 1: eclipse each other just about, which is a total cosmic coincidence.
Speaker 1: The Moon could have been bigger, or it could have
Speaker 1: been further, or it could have been closer. They don't
Speaker 1: have to be the same apparent size in the sky,
Speaker 1: and yet they are. Yeah, that's a pretty wild coincidence.
Speaker 1: Although it is also a function of where we are
Speaker 1: right now, right, because eventually the Moon is going to
Speaker 1: move further away from Earth and so it will look
Speaker 1: smaller than the Sun. Yeah, exactly, it gets smaller and
Speaker 1: smaller every year, and before like it maybe increased or
Speaker 1: times or millions of years ago, the moon looked bigger
Speaker 1: than the Sun during a solar eclipse. Yeah, And the
Speaker 1: Sun is also growing in size as it gets older, right,
Speaker 1: and pushing out more of its layers further and further.
Speaker 1: So the Sun is getting bigger and the Moon is
Speaker 1: getting smaller. And it's a really valuable lesson about coincidences.
Speaker 1: You know, sometimes we see coincidences out there in the
Speaker 1: universe and we go, oh, there must be an explanation
Speaker 1: for that, and can't be by chance, But sometimes it is, right.
Speaker 1: We don't think there's a reason that the Moon and
Speaker 1: the Sun happened to appear to be the same size
Speaker 1: in our sky, but it seems like a huge coincidence.
Speaker 1: But sometimes they just happen. Yeah, And I guess the
Speaker 1: coincidence is that they're almost the same size and from
Speaker 1: our point of view and the sky. But it's sort
Speaker 1: of not a coincidence that it just happens to fly
Speaker 1: in front of the Sun, right, because the Moon is,
Speaker 1: you know, spinning around Earth all the time, and we're
Speaker 1: spinning around the Sun all the time, and so technically
Speaker 1: the Moon kind of sits everywhere at any point in
Speaker 1: the sky at some point eventually, right, So it's not
Speaker 1: a coincidence that it just happens to line front of
Speaker 1: the Sun, that's right. And most of the things in
Speaker 1: the Solar System are in the same plane, and so
Speaker 1: it's possible for them to line up. If the Moon,
Speaker 1: for example, was orbiting the Earth outside the plane of
Speaker 1: the Earth's orbit, it would be much harder for it
Speaker 1: to eclipse the Sun. But because it moves around in
Speaker 1: the same plane than it gets itself between the Earth
Speaker 1: and the Sun, and of course it doesn't eclipse the
Speaker 1: entire Earth. The Moon casts a shadow on the Earth,
Speaker 1: and that shadow moves across the surface of the Earth.
Speaker 1: When you're in that shadow, then you can see the eclipse.
Speaker 1: And at the same time, there are people who are
Speaker 1: not in that shadow who can still see the Sun
Speaker 1: sort of around the side of the moon because they
Speaker 1: have a different angle. I saw the total eclips back
Speaker 1: in two thousand eighteen. Was it? It was pretty awesome event. Yeah,
Speaker 1: And there's another one coming up in a in a
Speaker 1: year or two. Right. There are a bunch of eclipses
Speaker 1: all around the world the next few years, and if
Speaker 1: you have the opportunity to see them, I totally encourage you.
Speaker 1: Even though it has no deep astronomical significance, is just
Speaker 1: sort of like a cool event. It makes you feel
Speaker 1: connected to people who have seen these things since prehistoric
Speaker 1: times and looked up and wondered, like, WHOA, something is
Speaker 1: different about the sky today. I wonder what that means. Yeah,
Speaker 1: just like I feel connected to my thumb whenever I
Speaker 1: put it in front of the sun. Are there times
Speaker 1: you don't feel connected to your thumb. That's what we
Speaker 1: should worry about. Sometimes I feel like the thumb is
Speaker 1: like we're not connecting into a deep level. You know,
Speaker 1: you and your thumb needs to go to therapy. It
Speaker 1: sounds like work out these issues. Yeah, yeah, do you
Speaker 1: know anyone Maybe there's a good podcast for that. Maybe
Speaker 1: I can point you to one I could point off
Speaker 1: with my index finger isn't talking to me either, so
Speaker 1: there's always a surprise in the podcast. This is the
Speaker 1: direction I never would have guessed. Yeah, but it's interesting.
Speaker 1: So what do you call a solar eclipse? Is when
Speaker 1: something blocks your view of it? Right, Like, you can
Speaker 1: also have a moon eclipse, right, the lunar eclipse, Yeah,
Speaker 1: that's right. That's when the Earth gets between the Sun
Speaker 1: and the Moon, and so the Moon is then blocked
Speaker 1: from the Sun by the Earth, and so you can
Speaker 1: still see the Moon, but it's sort of like shaded.
Speaker 1: It turns a funny color because it's no longer getting
Speaker 1: as much direct sunlight because it's in the Earth's shadow.
Speaker 1: So basically, eclipses are like when somebody gets into somebody
Speaker 1: else's shadow, right, or I guess technically a lunar eclipse
Speaker 1: is like an earth eclipse if you were standing on
Speaker 1: the moon. Yeah, although if you were in the moon
Speaker 1: you would probably call that is solar eclipse, right, because
Speaker 1: the Sun would be getting eclipsed. Are you saying it's
Speaker 1: all relative, Daniel, It's all relative and the names are
Speaker 1: not consistent. That's exactly the lesson of the podcast, all right.
Speaker 1: And so it's interesting that you can you can block
Speaker 1: out the light from the Sun, but that applies also
Speaker 1: to any star, right, Like, you can have eclipses out
Speaker 1: there in space with any star, not just our sun.
Speaker 1: That's right. Stars out there have their own planets, and
Speaker 1: those planets have moons, and so on those planets there
Speaker 1: are eclipses happening. Those planets. Moons are blocking that Sun's
Speaker 1: light and creating shadows which crawl along the surface of
Speaker 1: those planets around other stars, and maybe aliens are looking
Speaker 1: up at those and being impressed by the astronomical display.
Speaker 1: But we can actually see those eclipses as well, because
Speaker 1: sometimes those planets pass in front of their star, blocking
Speaker 1: a little bit of the light from that star. So
Speaker 1: instead of making a line from your eyeball to our sun, now,
Speaker 1: imagine a line from your eyeball to some star far
Speaker 1: far away, millions or billions of miles away, and a
Speaker 1: planet can pass along that line. Now, because you're so
Speaker 1: far away. The planet can't hope to block the entire star,
Speaker 1: but what it can do is dim it a tiny
Speaker 1: little bit. And that's actually one way that we discover
Speaker 1: planets around other stars. We see them making these sort
Speaker 1: of many or partial eclipses of their star. Yeah, it's
Speaker 1: one way we can detect a planet and other stars.
Speaker 1: And in fact, you sort of look for its stars
Speaker 1: that twinkle a little bit periodically, right with a constant beat,
Speaker 1: and that kind of tells you, hey, maybe it has
Speaker 1: a planet swinging around it. Yeah. You study the brightness
Speaker 1: of the star and you notice a dimming and it
Speaker 1: dims periodically. So it dims for like a few days,
Speaker 1: and then it gets bright again for a fixed amount
Speaker 1: of days, and then dims again, and it happens periodically,
Speaker 1: and that's how you can tell that something is going
Speaker 1: in front of it and blocking it, because otherwise stars
Speaker 1: can just twinkle and dust clouds can interfere with your observation.
Speaker 1: But if it's something regular, then you know that it's
Speaker 1: probably something orbiting near the star that's moving around it.
Speaker 1: And so it's a really powerful way to discover these
Speaker 1: other planets and also to measure their size because the
Speaker 1: more dimming you get the bigger the planet is, and
Speaker 1: these are always tiny little eclipses. You need really sensitive
Speaker 1: telescopes to even notice that these things are dimming. You
Speaker 1: could never see this with a naked eye, right, And
Speaker 1: so if you see a star out there dimming and
Speaker 1: being eclipse regularly, it might be a planet in its orbit.
Speaker 1: But it's kind of interesting also to think about that.
Speaker 1: You know, there are probably eclips is happening all the
Speaker 1: time with all the stars out there, right, Like maybe
Speaker 1: even asteroid flies near us, or it gets in our
Speaker 1: way between us and another star. Technically that's an eclipse too. Yeah,
Speaker 1: that's probably true, And there are eclips is happening that
Speaker 1: we can't see, right this technique of seeing these planets
Speaker 1: and we're lo eyes on the planet lining up with
Speaker 1: our line of sight to that star. There are plenty
Speaker 1: of planets out there around stars that are just not
Speaker 1: aligned with us. Like we talked about how in our
Speaker 1: Solar system, the Moon and the Earth and the Sun
Speaker 1: of mostly aligned in the disc of the Solar system.
Speaker 1: But the disc of our Solar system is not the
Speaker 1: same as the disc of other solar systems. Those are
Speaker 1: mostly random. I mean every solar system has its own
Speaker 1: disc and the planets mostly follow that disc, but the
Speaker 1: arrangement of our disc relative to other Solar System discs
Speaker 1: is kind of random, which means that most stars, when
Speaker 1: their planets passes in front of them, don't cause an
Speaker 1: eclipse that we can see. All right, Well, we're talking
Speaker 1: about whether or not you can involve a black hole
Speaker 1: in an eclipse, and so Daniel, can can you eclipse
Speaker 1: a black hole? Or can a black hole eclipse something else? Yeah,
Speaker 1: it's a really fun question. Let's first talk about whether
Speaker 1: you can eclipse a black hole. And the very question
Speaker 1: is like, well, could you see a black hole anyway? Right? Like, technically,
Speaker 1: what does it mean to see a black hole? Like,
Speaker 1: even if there was nothing between you and the black hole,
Speaker 1: are you actually seeing a hole? Like the whole it
Speaker 1: was the absence of something, right, Exactly. A shadow can't
Speaker 1: cast a shadow, right in the case of an eclipse
Speaker 1: on the Earth, the moon is casting a shadow on
Speaker 1: the Earth. But a black hole doesn't give off anything
Speaker 1: to create a shadow. And so technically a pure classical
Speaker 1: general relativity black hole is completely black. You saw it
Speaker 1: out in the middle of space, you would not see
Speaker 1: it doesn't give off any light. The only way you
Speaker 1: could see it is if it was in front of
Speaker 1: something else that was bright. It was like passing in
Speaker 1: front of a star and eclipsing it. So a classical
Speaker 1: black hole doesn't give off any light. Something could technically
Speaker 1: block your view of the black hole, right, Like if
Speaker 1: a planet happened to fly between you and the black hole,
Speaker 1: you wouldn't see the black hole anymore? Would you call
Speaker 1: that an eclipse? That sounds like a legal decision? Mean
Speaker 1: the black hole not giving off any light than is
Speaker 1: it being eclipsed? Right, And let's say behind the black
Speaker 1: hole isn't like a galaxy or something bright or a
Speaker 1: cloud of a bright cloud of gas or something, so
Speaker 1: you can actually without the planet blocking, you would see
Speaker 1: the black hole. But now there's a planet between you
Speaker 1: and the black hole, so you don't see the black hole.
Speaker 1: And technically it would sort of look like an eclipse, right,
Speaker 1: It would be like a black circle getting blocked by
Speaker 1: something maybe brighter. Yeah, that's technically possible. But we do
Speaker 1: think that black holes do give off a little bit
Speaker 1: of radiation in some cases, and the black holes create
Speaker 1: an environment that gives off a lot of radiation, a
Speaker 1: lot of light. So if you move away from just
Speaker 1: like the classical general relativity pure black sphere and talk
Speaker 1: about like the quantum version of it, or if you
Speaker 1: talk about the stuff around the black hole, in the
Speaker 1: environment created by the black hole, then that could be eclipsed, right,
Speaker 1: because what stuff falls into the black hole, it tends
Speaker 1: to get sped up so fast that it actually burns up.
Speaker 1: And then that's right right. So things when they come
Speaker 1: near the black hole, they don't always fall right in.
Speaker 1: I mean, if your head is straight for the black hole,
Speaker 1: you're going into the black hole. But if you sort
Speaker 1: of go near the black hole, then you get bent
Speaker 1: towards it and you sort of spin around it for
Speaker 1: a long time before falling in. And so that's all
Speaker 1: the accretion disc. It's like stuff that's on deck to
Speaker 1: be sucked into the black hole. And while you're in
Speaker 1: the accretion disk, the black hole is still working you.
Speaker 1: It's got these tidal forces. It's pulling on the part
Speaker 1: that's closer to you harder than the part that's further
Speaker 1: from you, because gravity is stronger for closer things, and
Speaker 1: so big clouds of gas and dust that are about
Speaker 1: to fall into the black hole have a lot of
Speaker 1: internal friction because of the black holes tidal forces, so
Speaker 1: they get heated up incredibly hot and admit a lot
Speaker 1: of radiation, and some stuff almost falls into the black hole,
Speaker 1: but the strong magnetic fields like guided around the black
Speaker 1: hole and it gets spun out at the top of
Speaker 1: the black hole, making these enormous jets of radiation. So
Speaker 1: black holes, even though themselves past the event horizon are black,
Speaker 1: the stuff around them could actually be very, very bright.
Speaker 1: These things quasars are some of the brightest things in
Speaker 1: the universe. Yeah, we've had episodes about that. Now. It's
Speaker 1: kind of ironic, right that some of the brightest things
Speaker 1: in the universe actually come from black holes. Yeah, because
Speaker 1: they are the source of a lot of gravitational energy,
Speaker 1: so they can speed stuff up, they can focus stuff,
Speaker 1: they can shoot stuff in another direction, even though you know,
Speaker 1: if they actually ate that stuff up, you would never
Speaker 1: see it. But when they're not actually eating stuff, they're
Speaker 1: also powering the acceleration of other stuff nearby, which creates
Speaker 1: fantastical light shows. And those light shows can be eclipsed
Speaker 1: right right, although, as you said earlier, not every black
Speaker 1: hole has these light shows, right, Like, there's a whole
Speaker 1: range of black holes. There are maybe black holes who
Speaker 1: are sitting all by themselves somewhere with nothing around it
Speaker 1: to feed it to make it bright. And there are
Speaker 1: black holes with huge clouds of stuff that is constantly
Speaker 1: falling into the black holes. Yeah, there's a broad diversity
Speaker 1: of black holes. The ones with big accretion disks are
Speaker 1: the ones that are easier for us to see because
Speaker 1: you can see the accretion disk right. Otherwise, it's very
Speaker 1: difficult to spot a black hole. You have to see
Speaker 1: it passing in front of something else. You have to
Speaker 1: see it eclipsing something in order to spot it. Mostly
Speaker 1: the way that we've identified black holes is from their
Speaker 1: accretion disk or from like the motion of stuff near them,
Speaker 1: indicating that there must be something very very heavy but
Speaker 1: not right there. Well, I think I see what you're saying. Like,
Speaker 1: if you define an eclipse as when you're blocking the
Speaker 1: light that's coming from something else, then you sort of
Speaker 1: need the situation where the black hole is giving off
Speaker 1: light from its incretion disk to have a black hole eclipse. Yeah,
Speaker 1: Otherwise you're just having a shadow of a shadow. And
Speaker 1: I don't even know what that is, but probably exists
Speaker 1: in the Pokemon universe. A shadow of a shadow is
Speaker 1: a it's a double shadow, it's a shadow squared. But
Speaker 1: I guess you could thankically block the shadow of a shadow, right,
Speaker 1: like you could blog looking at the shadow. Yeah, I suppose.
Speaker 1: I mean, if you stand in a shadow, do you
Speaker 1: still have your own shadow? I don't know. That's a
Speaker 1: philosophical question. That's like the sound of one hand clapping. Well,
Speaker 1: I guess you need like a third source of light
Speaker 1: or something, right, right, Yeah, and then you can also
Speaker 1: it's a complicated shadows, but you're saying there's a situation
Speaker 1: in which a black hole could have an increation disk
Speaker 1: around it, which would make it bright, in which case
Speaker 1: something could float between you and it and block your
Speaker 1: view of this light source exactly, And that would be
Speaker 1: a really powerful way to see interesting things really really
Speaker 1: far away. Because black holes are very very bright when
Speaker 1: we see them. We can see them in very very distant,
Speaker 1: very ancient galaxies. So the very powerful probe of what's
Speaker 1: out there in the universe. There's sort of like these
Speaker 1: pencil rays of light that shine out into the universe.
Speaker 1: We can use them to measure like the density of
Speaker 1: stuff along that ray. We once talked about the cosmic
Speaker 1: web and how we use these pencil rays of light
Speaker 1: from quasars to like illuminate the universe and tell like
Speaker 1: where the dark matter is and where these filaments of
Speaker 1: gas between the galaxies are super interesting. And when something
Speaker 1: else happens to pass in front of that pencil ray
Speaker 1: of light in a way that we can see it,
Speaker 1: then we can use that to identify something. We can
Speaker 1: use that to see something that otherwise would have been
Speaker 1: invisible to us. So we can use these eclipses as
Speaker 1: ways to find stuff really really far away. Wait wait
Speaker 1: you mean, what what does this stuff do well? For example,
Speaker 1: the technique we talked about for finding planets around other
Speaker 1: stars that mostly only works in our galaxy because the
Speaker 1: stars have to be close enough for us to like
Speaker 1: resolve a single star and measure its brightness very effectively.
Speaker 1: So it's very difficult to see exoplanets in other galaxies
Speaker 1: because remember, our galaxies like a hundred thousand light years across.
Speaker 1: Other galaxies are like millions of light years away, So
Speaker 1: we can't really use that technique to find planets around
Speaker 1: stars in other galaxies. But scientists have recently used this
Speaker 1: to find planets passing in front of black holes in
Speaker 1: other galaxies because black holes are such intense sources of
Speaker 1: this kind of radiation whoa, because they act like a
Speaker 1: beacon within that other galaxy. But is this a planet
Speaker 1: that is part of the black hole system or is
Speaker 1: this like a random planet floating around another star that
Speaker 1: just happens to ones fly in front of the black hole.
Speaker 1: We don't know, and in the case of a recent observation,
Speaker 1: the theories that it might be a planet orbiting black
Speaker 1: hole with a period of about seventy years, which means
Speaker 1: that we wouldn't know for another seventy years because we'd
Speaker 1: have to wait that long to see the next eclipse.
Speaker 1: If it is in fact orbiting that black hole, it's
Speaker 1: just like a random transit, some blob passing in front
Speaker 1: of the black hole. Then it won't happen again. But
Speaker 1: they actually did see this. They looked out with the
Speaker 1: Chandra X ray telescope at a galaxy called the Whirlpool
Speaker 1: galaxy and they saw this kind of eclipse, meaning that
Speaker 1: we're looking at this galaxy that's far away, and we
Speaker 1: think that the light coming from it is a black hole.
Speaker 1: That's right. We can zoom in on one part of
Speaker 1: that galaxy, and they think that there's a binary system there.
Speaker 1: They have like a normal like star and around it
Speaker 1: is orbiting a black hole, and the black holes probably
Speaker 1: from some other star which collapsed and left a black hole.
Speaker 1: So the origin is probably some binary star system. Two
Speaker 1: stars orbiting each other, and that's a little bit surprisingly
Speaker 1: not uncommon, because stars tend to form near each other.
Speaker 1: One of them becomes a black hole. They have this
Speaker 1: binary system where the black hole is now like sucking
Speaker 1: material from the other star and it generates a very
Speaker 1: bright accretion disk. And so from that black hole you
Speaker 1: now have this invariant hence source of radiation, and the
Speaker 1: telescope consume in on that and see the radiation from
Speaker 1: the accretion disc of this black hole as it eats
Speaker 1: its sibling. Wait, the black hole is orbiting the Sun.
Speaker 1: I guess it. It's it's a smaller mass than the Sun. Well,
Speaker 1: the sort of orbiting each other, right, the two both
Speaker 1: came from stars, and the black hole doesn't have all
Speaker 1: the mass of the original star came from Probably these
Speaker 1: two stars started out similar mass, and so more accurately
Speaker 1: you would say they orbit each other m And then
Speaker 1: on top of that they think that maybe there's a
Speaker 1: planet orbiting around the black hole that's orbiting around the
Speaker 1: Sun exactly, because the black hole is actually quite small,
Speaker 1: it's very compact, and so when this planet passes in
Speaker 1: front of the black hole, it actually eclipses a good
Speaker 1: fraction of it. We would think about a planet transitting
Speaker 1: in front of a star in our galaxy, it's a
Speaker 1: tiny little dip in front of that star. But here,
Speaker 1: because the accretion disc in the black hole are very compact,
Speaker 1: every compressed by gravity, this planet actually blocked most of
Speaker 1: the light from the secretion disc as it passed forward.
Speaker 1: So you can look at like the brightness of this
Speaker 1: black hole over time, and they see this huge dip
Speaker 1: as something apparently eclipsed it. It clips the black hole,
Speaker 1: lips the black hole. Yeah, but they only saw this once,
Speaker 1: or have they seen this periodically. They've only seen it
Speaker 1: once and now have a model for this system and
Speaker 1: how far aware this plant would have to be and
Speaker 1: how big it is, and in that model it takes
Speaker 1: about seventy years to orbit this system. But of course
Speaker 1: they're not making the grad student wait seventy years to graduate,
Speaker 1: although it could have also been like an asteroid passing
Speaker 1: in front of the Chindra telescope or something that could
Speaker 1: have caused this dip. Right, Yeah, there's a lot of possibilities.
Speaker 1: We don't see this thing very directly. We only just
Speaker 1: see a dip in this black hole, which we otherwise
Speaker 1: can't explain, which means something probably passed in front of
Speaker 1: it to block our view. And one hypothesis is a planet,
Speaker 1: but we can't tell very precisely. Right, it could have
Speaker 1: been somebody's thumb. Maybe did you put your thumb on
Speaker 1: Chindre that day? Is that what happened? I don't know.
Speaker 1: My son doesn't tell me everything it does. That's the
Speaker 1: whole problem. But if it's true, then it's really interesting
Speaker 1: because it's the first time we've discovered a planet in
Speaker 1: a far away galaxy using this transit technique. Interesting. That's amazing,
Speaker 1: and it would be amazing to be on that planet.
Speaker 1: Can you imagine living on that planet and having like
Speaker 1: not just a sun but a black hole also kind
Speaker 1: of like sunrising and sunsetting every day and seeing the
Speaker 1: black hole eat your sun. Right, That sun gets dimmer
Speaker 1: and dimmer every year as the black hole pulls the
Speaker 1: material out of it. Wow, that'd be a pretty amazing
Speaker 1: view when you look up from that planet. I wonder
Speaker 1: if that's where Pokemon out from, that's where they get
Speaker 1: their Z power from the view. It's so amazing. Alright, Well,
Speaker 1: we've seen a black hole get eclipse, and there are
Speaker 1: other examples of that, and there's also the reverse situation
Speaker 1: of whether or not a black hole can eclip something else.
Speaker 1: So let's get into those. But first let's take another
Speaker 1: quick break. All right, we're talking about black hole eclipses,
Speaker 1: whether or not you can eclipse a black hole or
Speaker 1: whether a black hole can eclip something else. And it
Speaker 1: turns out that yes, you can eclipse a black hole.
Speaker 1: We've seen it. We have data from a black hole
Speaker 1: being eclipse out there in another galaxy. That's right. Even
Speaker 1: though black holes are super powerful in the real world
Speaker 1: and in Pokemon, you can just stand in front of
Speaker 1: them and block their light. Yeah, it's pretty amazing. We
Speaker 1: have data from that. And you said there's another example
Speaker 1: of a black hole eclipse that we've seen. That's right.
Speaker 1: There's a really cool galaxy about sixty million light years away.
Speaker 1: It goes by the exciting name of n GC, and
Speaker 1: it's exciting because it has a very active galactic nucleus.
Speaker 1: This is what astronomers say when they mean that there's
Speaker 1: a big black hole at the heart of it, and
Speaker 1: it's very powerful and it's shooting a lot of stuff out.
Speaker 1: So if you imagine a galaxy is like a big
Speaker 1: flat disc of stuff, maybe with arms trailing behind it.
Speaker 1: Now add to that huge jets of stuff shooting up
Speaker 1: and down sort of from the middle of that disk.
Speaker 1: So the galaxy is no longer just like flat. It
Speaker 1: now has like an axle around which it's spinning. And
Speaker 1: so we've seen this galaxy and and has something eclipses. Yeah,
Speaker 1: astronomers were really curious about what was going on in
Speaker 1: the heart of that galaxy, and they wanted to know
Speaker 1: how big was the black hole and how big was
Speaker 1: the active part of it, this sort of like really
Speaker 1: intense part of the center of the galaxy. How big
Speaker 1: is that accretion disk. Problem is that the galaxy is
Speaker 1: so far away that it's really hard to measure that.
Speaker 1: Like we've taken pictures of black holes and their acreation disks,
Speaker 1: but it's very very difficult, and for this galaxy, it's
Speaker 1: too far away for us to even use the event
Speaker 1: horizon telescope. So they were trying to figure out how
Speaker 1: big this thing was. And then they got lucky. They
Speaker 1: got lucky because a big cloud of gas, when they
Speaker 1: already knew and they had studied before, passed in front
Speaker 1: of the black hole and eclipsed it. Because they knew
Speaker 1: how big this cloud was and how fast it was going,
Speaker 1: they were able to use that to measure the size
Speaker 1: of the black hole accretion disc itself. Wait, what so
Speaker 1: there was a black hole in another galaxy far waing
Speaker 1: and a gas cloud within that galaxy pass in front
Speaker 1: of it, or between us and that other galaxy. The
Speaker 1: gas cloud is part of that other galaxy. You know, Oh,
Speaker 1: I see? And how do we know how big that
Speaker 1: gas cloud was? Because it's so far away. It's so
Speaker 1: far away, but it's really big. And so they were
Speaker 1: able to measure the size of this gas cloud. It's
Speaker 1: much bigger than the black hole, but it's big enough
Speaker 1: to see with the telescopes. It's big enough to see. You.
Speaker 1: We can see other galaxies and we can see individual
Speaker 1: components of it. We can't always resolve things as small
Speaker 1: as stars, but big gas clouds we can resolve. And
Speaker 1: so the cloud eclipse the black hole in the middle
Speaker 1: or the quasar in in the middle, like it blocked
Speaker 1: it completely or it just made it kind of fuzzy
Speaker 1: for a while. It blocked it almost completely. I mean,
Speaker 1: some light can get through it at some wavelengths. But
Speaker 1: you can see definitely the dramatic dimming of this black
Speaker 1: hole because this cloud passes in front of the accretion disk,
Speaker 1: and so as it passes in front of one side
Speaker 1: of the acreation disc, it starts to dim. And then
Speaker 1: if it's totally blocking the disk, then you get the
Speaker 1: minimum brightness. And then as it starts to reveal the
Speaker 1: accretion disc again, the light comes back up. And so
Speaker 1: from the size of the gas cloud and the speed
Speaker 1: and with the gas cloud was moving, you can figure
Speaker 1: out the size of the accretion disk, which is what
Speaker 1: the astronomers are really curious to know. Interesting, So these
Speaker 1: are recorded instances of black hole eclipses, Like you could
Speaker 1: be the astronomer that saw a black hole eclip. Yeah, exactly.
Speaker 1: And these are lucky coincidences, right, just like the Sun
Speaker 1: and the moon lining up. In the case that these
Speaker 1: things line up in the sky, we can use that
Speaker 1: to learn something about these systems. We're always taking an
Speaker 1: advantage of what's going on in the universe. Astronomers never
Speaker 1: get to like build experiments and say what happens if
Speaker 1: I crash these two things together, or if I pass
Speaker 1: this in front of the other thing. They have to
Speaker 1: just be clever in other ways of saying, well, I
Speaker 1: didn't get to design this situation, but what can I
Speaker 1: do to learn about the universe? Frum it anyway, And
Speaker 1: so I love seeing astronomers be clever this way and
Speaker 1: figure out, like how to use the lucky lining up
Speaker 1: of these two objects to learn something about them. And
Speaker 1: in this case, I used the gas cloud to learn
Speaker 1: about the size of this black hole. What did they
Speaker 1: learn about it? So they learned the size not just
Speaker 1: to the black hole, but also the disc around it, right,
Speaker 1: because it's the disc around it, the accretion disc that
Speaker 1: really is generating that radiation. So they learned that this
Speaker 1: disc is about seven a U wide, where a us
Speaker 1: the distance from the Earth to the Sun. And so
Speaker 1: if you put this thing in our solar system and
Speaker 1: you extend out past the Earth's orbit and out past Mars,
Speaker 1: so this thing is really pretty big. Wait, we can
Speaker 1: measure the size of the cloud before, but we couldn't
Speaker 1: measure the size of the black hole. Yeah, and the
Speaker 1: cloud is bigger than the black hole, so we were
Speaker 1: able to resolve it all right. Well, the final question
Speaker 1: is whether a black hole could eclipse something else. Like
Speaker 1: if there's a star or a sun out there and
Speaker 1: a black hole pass in between it and us, would
Speaker 1: it create an eclipse? That would be pretty dramatic, wouldn't it.
Speaker 1: That would be pretty dramatic, But it's almost impossible. If
Speaker 1: somebody standing on the other side of a black hole
Speaker 1: and like turning on and off a flashlight, then a
Speaker 1: lot of those photons would get to you anyway. Remember
Speaker 1: that space around the black hole is really really curved,
Speaker 1: so light doesn't always travel in straight lines. So light
Speaker 1: that comes out from their flashlight that wouldn't otherwise get
Speaker 1: to your eye gets bent by the black hole towards
Speaker 1: your eye. So the black hole would eat some of
Speaker 1: the photons from the flashlight, but other photons that were
Speaker 1: going in other directions would get bent towards your eyeball,
Speaker 1: so you would still see it. Right, Like if a
Speaker 1: black hole just happened to fly into our solar system
Speaker 1: and get between us and the Sun, it wouldn't totally
Speaker 1: block the Sun. It would only block some of it. Yeah, Like,
Speaker 1: if somebody stood on the other side of a black
Speaker 1: hole with a laser of single photons, they could shoot
Speaker 1: them at the black hole and you would eat them
Speaker 1: and you wouldn't see it. But if their source has
Speaker 1: any sort of width to it, if the photons come
Speaker 1: out at any sort of angle, then some of those
Speaker 1: are going to get bent around the black hole and
Speaker 1: towards your eye. We see the same thing happening actually
Speaker 1: already with the moon the Desiginstein's famous proof of general
Speaker 1: relativity that space is curved by mass, because he showed
Speaker 1: that photons from the Sun don't always get blocked by
Speaker 1: the Moon. The Moon bends them around itself a tiny
Speaker 1: little bit. The Moon is lensing the light from the
Speaker 1: Sun a little bit, and a black hole would be
Speaker 1: a very very powerful gravitational lens. So it's almost impossible
Speaker 1: to hide behind a black hole, right, you're saying, like,
Speaker 1: because the Moon is almost the same size as the
Speaker 1: Sun and the sky, it doesn't totally block the Sun
Speaker 1: because some of the light kind of flows around the
Speaker 1: Moon and gets to us anyway. But if the Moon
Speaker 1: was bigger, right, and the sky might like ten times
Speaker 1: bigger than the Sun. It would almost totally blocked the Sun, right, Yeah, exactly.
Speaker 1: Although the Moon was more massive than it would be
Speaker 1: more effective at bending some of the Sun's light towards us.
Speaker 1: And so there's two different effects going on there. And
Speaker 1: so something is very small, like a black hole and
Speaker 1: very very dense, it's going to be excellent at gathering
Speaker 1: light that otherwise wouldn't have gone to you and sending
Speaker 1: it your direction. So what would we see if a
Speaker 1: black hole stood between us and our son. We would
Speaker 1: see like a black circle with a bright ring around it, right,
Speaker 1: and then that ring would sort of merge with the
Speaker 1: Sun and kind of distort the light around it, and
Speaker 1: then they would block the Sun, and then it would
Speaker 1: keep going. Yeah exactly. It would look really weird and awesome.
Speaker 1: It reminds me actually of a great science fiction book
Speaker 1: I read, Paraheli In by Greg Egan. He talks about
Speaker 1: what happens when a black hole enters our solar system,
Speaker 1: and it's not something you should look forward to because
Speaker 1: it would disrupt everything in the solar system even before
Speaker 1: it made an impressive distortion of the Sun's light. Would
Speaker 1: be bad news, but let's say it was a really
Speaker 1: big black hole. It would totally eclipse our sun, right,
Speaker 1: or we we still see all of the light from
Speaker 1: the sun. We wouldn't, right, We would only see some
Speaker 1: of the light from the sun get bent around the
Speaker 1: black hole, but mostly it would be blocked. We wouldn't
Speaker 1: see all of the light from the sun because photons
Speaker 1: shot directly towards the center of the black hole would
Speaker 1: still fall into the black hole, but photons shot in
Speaker 1: other directions would get bent around it. To us, well,
Speaker 1: there would be a range, right, wouldn't there be a range? Like,
Speaker 1: It's not just the ones directly to the center of
Speaker 1: the black hole and the ones a little bit off
Speaker 1: to the side also get sucked into the black hole. Yeah,
Speaker 1: the bigger the black hole, or the closer you are
Speaker 1: to it, the sort of the wider range of photons
Speaker 1: that do fall into the black hole. But also the
Speaker 1: more powerful the black hole, the more it's able to
Speaker 1: bend other photons around it so that you can see it.
Speaker 1: And have we seen an example of this, I guess
Speaker 1: we kind of have, right, I mean, we've taken pictures
Speaker 1: of black holes, right, we have pictures of black holes,
Speaker 1: and presumably there are stars behind the black hole that
Speaker 1: we're not seeing because they're getting blocked by this black hole.
Speaker 1: I don't know that we've seen that directly. We've discovered
Speaker 1: smaller black holes because of their gravitational effects on the
Speaker 1: nearby stars. Like if you see a star and it's
Speaker 1: moving in such a way that you can tell it's
Speaker 1: orbiting something, but you don't see the thing there, then
Speaker 1: you deduce that there's probably a black hole there, even
Speaker 1: if you don't see it. I don't know if we've
Speaker 1: seen direct lensing of background stuff from a tellar mass
Speaker 1: black hole. Well, I guess if we have a picture
Speaker 1: of a black hole, technically it was blocking something behind it, right,
Speaker 1: assuming there was something behind it, then yeah, it's getting blocked. Yeah, well,
Speaker 1: technically there that has to be something behind it, doesn't there.
Speaker 1: I mean, it's not like they're it's totally empty space
Speaker 1: behind it, right, Yeah, there's always background galaxies no matter
Speaker 1: how far you look. All right, Well, I think your
Speaker 1: point is that it's complicated, right, because black holes bend
Speaker 1: space so much that it and they act like lenses
Speaker 1: out there in space that it's it's kind of a
Speaker 1: complicated situation to have a black hole block something else. Yeah,
Speaker 1: black holes are great at bending light and eating photons,
Speaker 1: but they're also great at showing you what's behind them. Yeah,
Speaker 1: but definitely, for sure, we've seen things block black holes
Speaker 1: from our view. It's just that the situation is more
Speaker 1: complicated for a black hole blocking our view of something else. Yeah, exactly.
Speaker 1: All right, Well, I think the main lesson is Pokemon
Speaker 1: is right. I think that's what you're seeing, right, that's right.
Speaker 1: You don't need a physics degree. You just invest your
Speaker 1: college savings in Pokemon. That's right. Just catch them all
Speaker 1: and you can't retired to that tropical island or at
Speaker 1: least pay for your son's college. It kind of caused
Speaker 1: the same these days, does cause the same. Maybe you'll
Speaker 1: get a PhD in Pokemon. I think there are pro
Speaker 1: hard people getting their PhDs on the cultural impact of Pokemon.
Speaker 1: I'm sure you can get a PhD on anything, exactly.
Speaker 1: Everybody can get a PhD. Al right, Well, I guess
Speaker 1: the next time you look out into the night sky
Speaker 1: or even the daytime sky, imagine that there are black
Speaker 1: holes out there being eclipse and also eclipsing our view
Speaker 1: of the universe. Because the universe is full of all
Speaker 1: these amazing objects and be impressed by how astronomers are
Speaker 1: taking an advantage of coincidences and happenstands out there in
Speaker 1: the universe to teach us lessons, to reveal the nature
Speaker 1: of the mysteries of our cosmos. That's right. The main
Speaker 1: lesson here is don't put your thumb down on physics.
Speaker 1: Give it those thumbs up. Yeah, two thumbs up to astronomy.
Speaker 1: All right. We hope you enjoyed that. Thanks for joining us,
Speaker 1: See you next time. Thanks for listening, and remember that
Speaker 1: Daniel and Jorge explained. The Universe is a production of
Speaker 1: I Heart Radio. For more podcast from my Heart Radio,
Speaker 1: visit the I Heart Radio app, Apple Podcasts, or wherever
Speaker 1: you listen to your favorite shows. Ye