Latest / Daniel and Kelly’s Extraordinary Universe / What would happen if the sun became a black hole?

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What would happen if the sun became a black hole? · Daniel and Kelly’s Extraordinary Universe

0:09
Speaker 1: Horror. Can I ask you a hypothetical question? I'm not
0:14
Speaker 1: a big fan of speculation. Well, my question is, what
0:17
Speaker 1: if you liked hypothetical questions? Isn't that a hypothetical question
0:21
Speaker 1: in itself? That's right, exactly, it's a hypo hypothetical question.
0:26
Speaker 1: In that case, I guess I would be very happy
0:29
Speaker 1: right now if I like hypothetical questions. In that universe
0:32
Speaker 1: in which you do like hypothetical questions, I've got one
0:35
Speaker 1: for you, all right, I am hypothetically excited. So do
0:40
Speaker 1: you worry about dramatic ways that the world might hypothetically end?
0:45
Speaker 1: I think I worry about any kind of way that
0:47
Speaker 1: the world might end, both the dramatic and the documentary.
0:51
Speaker 1: You mean in the actually hurtling down the road from
0:55
Speaker 1: to us from the future sort of imminent disasters that
0:58
Speaker 1: we're ignoring mostly because the are inconvenient. Well, what do
1:01
Speaker 1: you mean by dramatic? Like A like a like if
1:03
Speaker 1: the world turned into a giant banana or something that
1:06
Speaker 1: would be dramatic. But I hadn't mind things like, you know,
1:08
Speaker 1: getting zapped by an alien ray, or maybe the whole
1:11
Speaker 1: planet falling into a wormhole, or maybe getting smashed into
1:15
Speaker 1: some rogue asteroid or comment. Oh man, well, I wasn't
1:19
Speaker 1: worried before, but I am now. Well, be sure these
1:24
Speaker 1: are just hypothetical questions, and so all your worries are
1:27
Speaker 1: also hypothetical. I am hypothetically terrified. Well, let me hypothetically
1:32
Speaker 1: reassure you you probably should worry about all that stuff. Hi.
1:51
Speaker 1: I'm Daniel. I'm a particle physicist. And I'm Jorge. I'm
1:54
Speaker 1: a physical cartoonist and the creator of PhD Comms. And
1:59
Speaker 1: this is our podcast, Daniel and Jorge Explain the Universe,
2:03
Speaker 1: a production of My Heart Radio which we try to
2:06
Speaker 1: take you on a trip out into the universe to
2:08
Speaker 1: explore all of the amazing and incredible and potentially universe
2:13
Speaker 1: and earth ending things that can happen. That's right. We
2:16
Speaker 1: explore the real, we explore the conceptual, We explore the hypothetical,
2:20
Speaker 1: the universe in which Daniel starts the podcast instead of Joge.
2:24
Speaker 1: I wonder if people are a little bit freaked up
2:26
Speaker 1: by that. Listeners, you are in that universe. This is
2:31
Speaker 1: this is a hypothetical podcast right now. Now, we love
2:34
Speaker 1: to talk about things that happened in the universe, Things
2:36
Speaker 1: we understand, things we don't understand, but we've noticed in
2:39
Speaker 1: our emails that we've been getting a lot of hypothetical
2:42
Speaker 1: questions like what would happen if? And so today on
2:45
Speaker 1: the podcast, we'll be talking about one very dramatic question
2:50
Speaker 1: that people have been writing in about today's topic is
2:58
Speaker 1: what would happen if the Sun became a black hole?
3:03
Speaker 1: We need some dramatic music there. Not a white hole,
3:06
Speaker 1: not a rose hole, not something else entirely, but the
3:10
Speaker 1: sun became a black hole. And I think this is
3:12
Speaker 1: a fascinating question because I think people are intrigued by
3:16
Speaker 1: the concept of black holes, but they also find them
3:18
Speaker 1: mysterious and dangerous, you know, And so they're dangerous. I
3:23
Speaker 1: think the blackness of it, and you know, the mystery
3:25
Speaker 1: of it makes it a little scary. Yeah, And the
3:28
Speaker 1: the idea that, you know, we're comfortable here on Earth,
3:32
Speaker 1: but we live in a tiny little shell of gas
3:34
Speaker 1: on the crust, you know, on this cool crust floating
3:38
Speaker 1: above Magna, in a crazy, dramatic, powerful universe that could
3:42
Speaker 1: snuff us out in a moment without even noticing or caring.
3:46
Speaker 1: And so I think maybe this question reflects people's like
3:49
Speaker 1: feeling that our life on this planet is precarious, right,
3:52
Speaker 1: that there's things out there that are incredibly powerful and
3:55
Speaker 1: dangerous and uh, you know, and they wonder like could
3:58
Speaker 1: these things happen to us? Are most of the questions
4:01
Speaker 1: we get hypothetically about, uh, the end of the world
4:05
Speaker 1: and things like this. No, No, most of them are, hey,
4:08
Speaker 1: can you explain this? Or you said this on the
4:10
Speaker 1: podcast and I didn't understand, um, And I'm happy to
4:13
Speaker 1: answer those questions. But sometimes they are a bit more dramatic,
4:16
Speaker 1: and hey, maybe these are just questions from script writers
4:19
Speaker 1: working out their ideas, you know, um, and it's so
4:23
Speaker 1: awesome send us your ideas. We love to dig into them.
4:26
Speaker 1: But this one is not a crazy question, right, because
4:30
Speaker 1: I think maybe a lot of people know about black holes,
4:33
Speaker 1: and maybe a lot of people have heard that black
4:36
Speaker 1: holes come from stars, right from suns, that's right, Yeah,
4:40
Speaker 1: I mean the end a black hole is just a
4:42
Speaker 1: really a dense clump of mass, dense enough so that
4:45
Speaker 1: even light cannot escape. And you know, stars are also
4:48
Speaker 1: dense clumps of mass, and you're right, end point of
4:50
Speaker 1: a life of some stars is a black hole. And
4:53
Speaker 1: so I wouldn't say it's not a crazy question, but
4:56
Speaker 1: it's it's not a super crazy question. Yeah, absolutely, there's
5:00
Speaker 1: some some reason to that. We'll dig into that. But
5:03
Speaker 1: before before we do, I thought, let's see if this
5:07
Speaker 1: is something people wonder about. If this people worry about,
5:11
Speaker 1: what do people think would happen if the sun became
5:13
Speaker 1: a black hole? And so I walked around on the
5:16
Speaker 1: streets and these questions. I did not ask of people
5:19
Speaker 1: that you see Irvine, because I was out of town
5:21
Speaker 1: for the summer. But it's a rather international crowd. Folks
5:24
Speaker 1: in Heathrow Airport, folks on the streets, important Portugal folks anywhere.
5:29
Speaker 1: I found them speaking English, and we're willing to answer questions.
5:32
Speaker 1: Are you serious? Really? Yes, absolutely you were. This is
5:35
Speaker 1: our our international plot. That's right. I'm probably breaking all
5:38
Speaker 1: sorts of international laws about recording people. But you know,
5:43
Speaker 1: for you listen release for you'll hear a variety of
5:47
Speaker 1: accents and a variety of ideas. Awesome, So think about
5:50
Speaker 1: it for a second. Well, what do you think would
5:52
Speaker 1: happen if the sun, if our sun, our lovely, bright,
5:56
Speaker 1: beautiful sun, became a black hole? What do you think
5:58
Speaker 1: would happen? Here's what be had to say. Well, I
6:03
Speaker 1: guess we would suck in. We would be sucked in
6:06
Speaker 1: if you used it will be really dark outside. Then
6:10
Speaker 1: after that we can improve where lights some sense, we
6:13
Speaker 1: can't solve the problem. Solve that problem, however, Chetska is
6:17
Speaker 1: going to be the bigger problem. The Earth will whenish
6:21
Speaker 1: in the black hall. But this is not an option,
6:24
Speaker 1: I think, because no, I have no idea. A lot
6:28
Speaker 1: would happen, although we probably wouldn't know about it for
6:31
Speaker 1: eight minutes. We're far too close to be in a
6:34
Speaker 1: stable or with a black hole. Even if this of
6:38
Speaker 1: one solar mass, we would disappear into the into the Sun.
6:43
Speaker 1: That would be very difficult for farmers. I think the
6:46
Speaker 1: Sun would go through various phases before that, of its
6:50
Speaker 1: its core helium expanding or something changing gravitational forces. So
6:59
Speaker 1: I think by the time the Sun became a black hole,
7:04
Speaker 1: we would be either well fried or well suffocated or something.
7:09
Speaker 1: All right, not a lot of sunny answers or optimistic.
7:13
Speaker 1: A lot of a lot of bad things happened here,
7:15
Speaker 1: and people nobody thought it would be good news. Right,
7:20
Speaker 1: Nobody said yes, that sounds awesome. Finally my plan has
7:24
Speaker 1: come to fruition. No no evil villains out there, planning
7:28
Speaker 1: to make this happen. Um. There's sort of two categories
7:30
Speaker 1: of answers. I thought, like one is people thought, well,
7:33
Speaker 1: that's just the end, because there's a black hole nearby.
7:35
Speaker 1: We're getting sucked in, right an The other one because
7:39
Speaker 1: that's what black holes do. They suck. That's what they do.
7:44
Speaker 1: Black holes suck. Um. And the other category is, you know, well,
7:49
Speaker 1: if the black the sun becomes a black hole, then
7:51
Speaker 1: it's no longer a sun, and we sort of rely
7:53
Speaker 1: on the sun being a sun providing light and heat,
7:57
Speaker 1: and so that would also kind of suck in a
7:59
Speaker 1: different way. I like the person who said it would
8:01
Speaker 1: be bad news for farmers exactly, like like just farmers.
8:08
Speaker 1: Everyone else would be cool with it, but farmers they
8:11
Speaker 1: won't get that, you know, farmers tank. Yeah. Well, you
8:14
Speaker 1: know that answer came from a guy who runs a
8:16
Speaker 1: farm in Portugal, and so maybe that was on the
8:19
Speaker 1: forefront of his mind. Is that possible? Could our son
8:21
Speaker 1: become a black hole? And you know, there we can
8:24
Speaker 1: give a pretty definitive answer, right there is almost no
8:27
Speaker 1: universe in which our son becomes a black hole. And
8:31
Speaker 1: that might be surprised or farmers everywhere or relie you
8:35
Speaker 1: can hear Jorge stopping to pack his emergency go bag. No,
8:40
Speaker 1: it's not something that power down. Hey, I didn't get
8:45
Speaker 1: an invite to your emergency spaceship. Why is that you
8:47
Speaker 1: powered the thing up? You're packing it, and you had
8:50
Speaker 1: your own I thought, oh, man, awkward, I thought you had.
8:54
Speaker 1: You should have talked about this. It's kind of embarrassing.
8:57
Speaker 1: Some stars become a black hole, and the basic idea
8:59
Speaker 1: is gotta have enough mass, right, you don't have enough
9:02
Speaker 1: mass to create enough gravity to pull the thing together
9:06
Speaker 1: to make a black hole, then you just get sort
9:09
Speaker 1: of a dense blob of stuff. Anything above like six
9:12
Speaker 1: or eight, maybe ten masses of our sun solar masses
9:16
Speaker 1: can become a black hole. Um, stars that are smaller
9:19
Speaker 1: than that don't have enough gravity to squeeze things together
9:23
Speaker 1: to become a black hole. That doesn't sound like a
9:25
Speaker 1: very safe margin of error, you know what I mean? Like,
9:28
Speaker 1: if our son was just you know, a couple of
9:30
Speaker 1: times bigger, it would totally pretty possible. I don't know,
9:33
Speaker 1: the Sun is pretty big, dude, So we're talking about
9:35
Speaker 1: a huge amount of stuff you need to add, Like
9:38
Speaker 1: ten solar masses is not just like the change in
9:40
Speaker 1: your pockets. Right, it's a huge amount of stuff, I guess.
9:44
Speaker 1: I mean, how confident are you on that map? You know,
9:49
Speaker 1: is it like it would never be able to turn
9:51
Speaker 1: into a black hole, or is it like not likely
9:54
Speaker 1: to get turned into a black or he starts to
9:55
Speaker 1: power up his spaceship again, I can hear it. Know,
10:00
Speaker 1: we're fairly certain that the Sun is not going to
10:02
Speaker 1: become a black hole. But that doesn't mean that, like
10:05
Speaker 1: it's all cool, right the Sun. We did talked about
10:08
Speaker 1: this on a whole other podcast. The Sun is going
10:10
Speaker 1: to end its life when it's done with its fusion cycle.
10:13
Speaker 1: And when that and before that happens, it's going to
10:15
Speaker 1: expand and get huge, and the radius of the Sun
10:19
Speaker 1: will be larger than the orbit of the Earth, meaning
10:22
Speaker 1: that the Earth will be inside the Sun. Right, And
10:26
Speaker 1: so even though the Sun is not going to end
10:28
Speaker 1: its life as a black hole, that doesn't mean that
10:31
Speaker 1: when the Sun ends its life, will all still be
10:33
Speaker 1: happily here on Earth, farming in Portugal. We won't even
10:36
Speaker 1: need to see this black yeah, exactly if it, if
10:38
Speaker 1: it could turn into a black hole, we wouldn't even
10:40
Speaker 1: survive see it. Yes, So it doesn't actually even really
10:42
Speaker 1: matter if the Sun becomes a black hole or a
10:45
Speaker 1: white dwarf, which is much more likely, because we will
10:47
Speaker 1: be toast either way, unless, of course, we all cram
10:50
Speaker 1: onto Jorge Special Spaceship and we can just watch the
10:52
Speaker 1: party from the safety of Pluto. How big is this
10:56
Speaker 1: big ship anywhere? Now you went ahead and told everyone, Daniel,
11:01
Speaker 1: thanks a lot. You know, only our listeners, which of
11:04
Speaker 1: course are the most intelligent, best looking, privileged people on Earth.
11:09
Speaker 1: That's right. If you had to self select, you have
11:11
Speaker 1: to select the population of people to say, from humanity obviously,
11:17
Speaker 1: now boarding Zone A for Jorge Spaceship, our premium listeners, Daniel,
11:21
Speaker 1: Jorge explain the universe. Oh sorry, you haven't listened to
11:27
Speaker 1: all of our podcast episodes. Oh but you know, some
11:32
Speaker 1: people might be wondering about about what I said there
11:34
Speaker 1: because another podcast we said that you could take anything
11:37
Speaker 1: and make it a black hole, right, like and take
11:39
Speaker 1: a baseball and you make it small enough, you can
11:42
Speaker 1: make it a black hole. And that's true, right. All
11:44
Speaker 1: you need is a certain density of stuff. Um, but
11:47
Speaker 1: for stars you do need a certain density. But to
11:50
Speaker 1: get to that density you need a minimum mass because
11:54
Speaker 1: there's there are things that are preventing stars from just
11:57
Speaker 1: falling in. Right. The reason everything like your pillow and
12:00
Speaker 1: your hamster doesn't don't become black holes is because there
12:04
Speaker 1: are other forces preventing them from becoming super dense. And
12:08
Speaker 1: so for stars to have enough gravity to overcome the
12:12
Speaker 1: barriers to that density, they have to have a certain mass.
12:15
Speaker 1: I think what you're saying is that technically the Sun
12:18
Speaker 1: could become a black hole, right, Like, if the hand
12:21
Speaker 1: of God reached out and grabbed the Sun and squished it,
12:24
Speaker 1: it could become a black hole. But naturally, left to
12:27
Speaker 1: its own devices, our sun can't won't ever turn into
12:31
Speaker 1: black That's right. Exactly, if the hand we got reached
12:33
Speaker 1: out and squeezed all the mass in the Sun down
12:36
Speaker 1: to a ball about three kilometers wide or smaller, then
12:40
Speaker 1: it would be dense enough to be a black hole.
12:42
Speaker 1: But there's physics that prevent that from happening, right, Squeezing
12:46
Speaker 1: that stuff down would take a force that gravity can't do,
12:49
Speaker 1: and so gravity not being the hand of God, can't
12:52
Speaker 1: turn this mass into a black hole. But wait, into
12:55
Speaker 1: a ball three kilometers white, But then how big would
12:57
Speaker 1: the hole be? Would the whole bet three kilometers why
13:00
Speaker 1: you mean like I mean, like theon the event horizon life.
13:04
Speaker 1: If you've got all the mass of the Sun into
13:06
Speaker 1: a sphere three kilometers wide or less than the black hole,
13:09
Speaker 1: the event horizon would be three kilometers, right, And again,
13:13
Speaker 1: we don't know what's going on inside the event horizon
13:15
Speaker 1: of a black hole. We don't know if all that
13:17
Speaker 1: stuff is squeezed in at a little point at the
13:20
Speaker 1: center of singularity or sort of quantum fuzzed out, or
13:23
Speaker 1: if it's you know, distributing its some sort of weird pattern.
13:26
Speaker 1: We don't know, and actually doesn't even really matter um
13:30
Speaker 1: from a gravitational point of view, And that's the point
13:32
Speaker 1: we're gonna talk about later. If you're on the outside
13:35
Speaker 1: of a sphere, then the only thing that matters to
13:38
Speaker 1: affect how much gravity there is is just how much
13:41
Speaker 1: stuff there is in the inside of that sphere. Like
13:44
Speaker 1: you're standing on the surface of the Earth, the force
13:47
Speaker 1: of gravity from the Earth depends only on your distance
13:50
Speaker 1: from the center of the Earth and how much mass
13:53
Speaker 1: there is in the Earth. If you rearrange stuff inside
13:57
Speaker 1: the Earth, it doesn't change how much you weigh and
14:00
Speaker 1: change the force of gravity, right, which which is cool
14:03
Speaker 1: to think that if you go down to your basement,
14:05
Speaker 1: you literally weigh a little bit less, right, a little
14:08
Speaker 1: bit more, sorry, a little bit more. You get an airplane,
14:10
Speaker 1: you weigh less because you're further from the center of
14:12
Speaker 1: the Earth, and so you have a smaller force. But
14:16
Speaker 1: if if you go down into your basement, then there's
14:19
Speaker 1: less earth down. No, you're right, yeah, you're right. Yeah.
14:22
Speaker 1: If you drill into the earth, right, yeah, then there
14:27
Speaker 1: is less earth inside that sphere whose radius is your
14:31
Speaker 1: distance from the center of the Earth. Yes, you're absolutely right.
14:34
Speaker 1: So as you drill into the earth, your weight drops
14:36
Speaker 1: because eventually goes down to zero as you get to
14:39
Speaker 1: the center of the Earth if you're exactly the center
14:41
Speaker 1: of the Earth, and the gravity from all the bits
14:44
Speaker 1: cancels and you feel no force of gravity. So if
14:47
Speaker 1: you're trying to lose weight, just go down to your
14:49
Speaker 1: basement and yourself or or get an airplane. Interestingly, the
14:54
Speaker 1: force of gravity. Force of gravity is strongest on the surface, right,
14:57
Speaker 1: because as you leave the surface, you increase the radius
15:01
Speaker 1: from the center. The mass need is the same, but
15:03
Speaker 1: the radius increases, and if you drill down as the earth,
15:06
Speaker 1: the mass decreases faster than the radius squared term. So
15:10
Speaker 1: the surface of the Earth is where you are the heaviest. Well, um,
15:14
Speaker 1: we were talking about black holes though, that's right, um,
15:17
Speaker 1: But the point is if you took all the mass
15:20
Speaker 1: of the Sun and you squeezed it into a ball
15:22
Speaker 1: three kilometers of radius or less, it would be a
15:25
Speaker 1: black hole. But physics can't accomplish that. So right, so
15:30
Speaker 1: you know, hey, if aliens came by and they did
15:33
Speaker 1: something weird to the Sun, they could turn the Sun
15:35
Speaker 1: into a black hole. So let's explore that scenario where
15:38
Speaker 1: the hand of God or aliens turned the Sun into
15:41
Speaker 1: a black hole. What would happen. Let's get into that. So,
15:44
Speaker 1: assuming that it does happen, let's find out what it
15:48
Speaker 1: means for us. But first let's take a quick break.
16:03
Speaker 1: All right, So the hand of God Daniel came down
16:05
Speaker 1: and or went up and squished the Sun down into
16:08
Speaker 1: a black hole and uh, or Aliens went out there
16:13
Speaker 1: and use some special machine to turn our son into
16:15
Speaker 1: a black hole. What does that mean for us? Yeah?
16:18
Speaker 1: What does that mean for us? And I think a
16:20
Speaker 1: lot of people think, well, black holes suck stuff in,
16:23
Speaker 1: and so if there's a black hole that nearby, it
16:24
Speaker 1: would just suck us in, right, and that would be
16:27
Speaker 1: the end. And a lot of people we interviewed said that,
16:30
Speaker 1: But remember that gravity is not all powerful. Right. There
16:34
Speaker 1: is already a very strong gravitational force towards the center
16:37
Speaker 1: of our Solar system from the mass of the Sun.
16:40
Speaker 1: But the Earth is not getting sucked into the Sun
16:43
Speaker 1: right now? Right? Why not? Because the Earth is in orbit.
16:47
Speaker 1: It has too much velocity. Right. You can think of
16:50
Speaker 1: an orbit. It's sort of like constantly falling towards the
16:53
Speaker 1: center and missing because you have too much forward velocity.
16:57
Speaker 1: And that's what the Earth is doing that falling. Would
16:59
Speaker 1: you miss so you come back around and you miss again,
17:02
Speaker 1: and you come back around and you miss again. That's
17:03
Speaker 1: when being an orbit really mean. Yeah, sort of like
17:06
Speaker 1: forever falling down the stairs. Right. And if the Sun
17:10
Speaker 1: became a black hole, it wouldn't change the mass of
17:13
Speaker 1: the Sun, right, We're talking about just squeezing the Sun
17:15
Speaker 1: down to a smaller radius that becomes a black hole.
17:18
Speaker 1: It doesn't change the mass. And the gravitational forces we
17:21
Speaker 1: were saying a minute ago depends just on two things.
17:24
Speaker 1: The total mass inside that sphere, right, the sphere that's
17:28
Speaker 1: the radius um that's your radius from the center of
17:31
Speaker 1: the mass um. That's you mean, like all the maths,
17:35
Speaker 1: it's closer to you to the center of the Sun
17:38
Speaker 1: or the black yes, exactly um. And so if you're
17:41
Speaker 1: just squeezing the Sun smaller, that doesn't change that number.
17:45
Speaker 1: So it depends on that that the mass, and it
17:47
Speaker 1: depends on your distance from the center of the mass, right,
17:51
Speaker 1: and that number is not going to change either. So
17:53
Speaker 1: you could take the Sun and squeeze into a black hole,
17:56
Speaker 1: it wouldn't change the Earth's orbital dynamics at all. Just
18:00
Speaker 1: because it's a black hole doesn't mean it magically has
18:03
Speaker 1: a greater gravitational poll. It's the same gravitational force. Nothing
18:07
Speaker 1: magic happens when it becomes a black hole, that's right.
18:10
Speaker 1: The only thing that changes is the gravitational effect um
18:15
Speaker 1: on things that are super close to the black hole.
18:17
Speaker 1: Before the Sun became a black hole. In this hypothetical example,
18:21
Speaker 1: the closest you could get to it is the surface
18:23
Speaker 1: of the Sun. That's where the strongest gravitational force was.
18:26
Speaker 1: Right Now, because you've squeezed the Sun down, you can
18:30
Speaker 1: get closer, and so there is a stronger gravitational force,
18:34
Speaker 1: right because you can get closer to this, to this
18:36
Speaker 1: mass than just the surface of the Sun, than the
18:39
Speaker 1: radius to the Sun, because now you shrunk the radius down.
18:42
Speaker 1: So there is a region, a new region where the
18:46
Speaker 1: gravitational force is stronger than anything used to be. But
18:49
Speaker 1: the Earth is not in that region, and the gravitational
18:51
Speaker 1: force at the rateus the Earth doesn't change at all.
18:54
Speaker 1: So the Earth would just orbit this black hole the
18:57
Speaker 1: way the Earth orbited the Sun. I think it might
18:59
Speaker 1: make we help people to think about, like maybe not
19:02
Speaker 1: like a dramatic collapse into a black hole, but just
19:05
Speaker 1: like imagine the Sun you know, shrinks a little bit,
19:08
Speaker 1: you know, like gets a little bit more dance or compact,
19:11
Speaker 1: or if it like fluffs up a little bit and
19:13
Speaker 1: gets a little bit bigger and fluffier, it's still the
19:16
Speaker 1: same amount of mass. And so our orbit wouldn't be
19:20
Speaker 1: effective if the Sun got a little bit fluffier or
19:23
Speaker 1: a little bit denser. Right, that's exactly right. So if
19:25
Speaker 1: the Sun shrank by one percent, right, and the mass
19:28
Speaker 1: did the same, it wouldn't change our orbit. And so
19:31
Speaker 1: if it shrank by or yeah, we still be going
19:39
Speaker 1: around the exact same orbit. Yeah, exactly, And and things
19:42
Speaker 1: do orbit black holes, right, The most direct way that
19:45
Speaker 1: we've seen black holes is from stuff orbiting them. There's
19:48
Speaker 1: a black hole in the center of our galaxy, and
19:50
Speaker 1: we see stars moving around it, and we can calculate
19:53
Speaker 1: the mass that black hole based on the orbit of
19:55
Speaker 1: the stars. We see gas orbiting black holes and being
19:59
Speaker 1: squeezed in the sage by the title forces and emitting
20:01
Speaker 1: crazy radiation, and so we see stuff orbiting black holes.
20:05
Speaker 1: Stuff does orbit. It's not like everything near a black
20:08
Speaker 1: hole just automatically get sucked in, right, And so the
20:12
Speaker 1: same thing would happen here. Well, I guess the part
20:14
Speaker 1: that is tripping me up is that, you know, I
20:16
Speaker 1: can imagine the Sun collapsing ten percent and still the
20:21
Speaker 1: Earth goes around on the same orbit. But you know,
20:24
Speaker 1: at some point the Sun, you know, something sort of
20:27
Speaker 1: magical happens, right, like suddenly becomes a black hole and
20:30
Speaker 1: you have an event horizon and you see the black dot.
20:33
Speaker 1: And so you're telling me that really, nothing sort of
20:37
Speaker 1: magical happens, right, like nothing from our point of view,
20:40
Speaker 1: nothing changes, Like the fact that it suddenly became a
20:43
Speaker 1: black hole doesn't suddenly make it like a bigger sucker.
20:49
Speaker 1: That's right. It doesn't make it bigger sucker stuff at
20:51
Speaker 1: our radius, right, so you know, one a U nine
20:55
Speaker 1: million miles from the Earth, the force of gravity doesn't change. Also,
20:59
Speaker 1: at where the surface of the Sun used to be,
21:02
Speaker 1: the force of gravity hasn't changed, because again you're at
21:04
Speaker 1: the same distance, right, and the same amount of stuff.
21:08
Speaker 1: But now I say you were like at half the
21:11
Speaker 1: radius of the old sun. Right, this is a place
21:14
Speaker 1: you can see that's now empty space that used to
21:16
Speaker 1: be the center of the Sun. So you couldn't get there.
21:19
Speaker 1: But now there's a spot there where there's incredibly strong gravity.
21:23
Speaker 1: You can get closer and closer to the surface. Remember,
21:26
Speaker 1: as we said before, the strongest gravity of any object
21:29
Speaker 1: is at its surface, and now that surface is much
21:31
Speaker 1: much closer to the center of all the mass, and
21:35
Speaker 1: so on the surface the gravity is much much stronger.
21:39
Speaker 1: So it is sort of magical in that way. So
21:42
Speaker 1: it's it's sort of like you open up new real
21:44
Speaker 1: estate in our solar system, but you you sort of
21:46
Speaker 1: don't want to be in the real estate because the
21:48
Speaker 1: gravitational forces are going to be crazy. Exactly. You've opened
21:51
Speaker 1: up new, crazy, intense real estate, but it's on a
21:53
Speaker 1: crazy hill, and you don't want to buy there exactly, um,
21:57
Speaker 1: because you're just gonna roll right down into the ocean. Um.
22:01
Speaker 1: And and so you know, people might feel like, oh, well,
22:03
Speaker 1: how can it not change anything to create a black hole?
22:06
Speaker 1: It does change something, right, It just doesn't change anything
22:09
Speaker 1: outside the radius of the old Sun because they're the
22:13
Speaker 1: gravity is the same. It wouldn't affect our orbit, right,
22:17
Speaker 1: Like the Earth would still take a year to go
22:19
Speaker 1: around it, and we would probably still spin one once
22:23
Speaker 1: a day. Um, but it would probably have other pretty
22:26
Speaker 1: bad effects, right, yeah, absolutely, all right, let's get into that.
22:30
Speaker 1: But first let's take another quick break. All right. I know,
22:45
Speaker 1: so if the Sun became a black hole suddenly, we
22:48
Speaker 1: wouldn't affect our orbit, right, We would still go around
22:51
Speaker 1: in once a year, and we would still spin around
22:53
Speaker 1: one a day, but it would have other kind of
22:58
Speaker 1: bad effects, right, that's right. If you have solar panels
23:01
Speaker 1: on your roof and you're using them to power your tesla,
23:04
Speaker 1: for example, then you're gonna need to figure something else
23:08
Speaker 1: out because if the Sun becomes a black hole, it's
23:11
Speaker 1: no longer fusing and no longer giving off light, and
23:16
Speaker 1: that light is the source of all energy and you know,
23:20
Speaker 1: animation of life on Earth. And so yeah, again pretty
23:23
Speaker 1: dark eight minutes later, and uh, sort of never lighten
23:28
Speaker 1: up again. It would be basically nighttime forever. Wait, so
23:31
Speaker 1: that a black hole is totally cold, right, It's not
23:35
Speaker 1: emitting any radiation or light. It might be emitting some
23:38
Speaker 1: very very low level of radiation called Hawking radiation, but
23:41
Speaker 1: that's never been experimentally confirmed. And even if it is,
23:46
Speaker 1: it's a tiny amount of radiation. And I mean the
23:50
Speaker 1: amount of radiation the Sun currently gives out is incredible.
23:53
Speaker 1: I mean it's almost a hundred million miles away, and
23:58
Speaker 1: yet it can burn you, right, can fry your eyeballs
24:01
Speaker 1: if you stare at it for a few seconds. So
24:04
Speaker 1: the amount of radiation coming off that thing is huge.
24:06
Speaker 1: Now you suddenly just delete all that radiation, right, and
24:10
Speaker 1: so the Solar system becomes a very dark place very quickly.
24:13
Speaker 1: Wait what happens to all that radiation? It just stays
24:16
Speaker 1: inside of the black hole. Now, well, the radiation comes
24:19
Speaker 1: from fusion, right, Like, where does that radiation come from?
24:22
Speaker 1: The Sun is a huge ball of plasma. It's fusing
24:25
Speaker 1: and releasing energy, right, and a black hole is not
24:29
Speaker 1: doing that. A black hole. Usually a black hole's form
24:32
Speaker 1: when a star can no longer do fusion, right, because
24:36
Speaker 1: the fusion is preventing a star from collapsing. Gravity is
24:39
Speaker 1: pulling the star in trying to squeeze it down, and
24:42
Speaker 1: a fusion is this explosion. It's constantly happens blowing the
24:45
Speaker 1: star up to keep it from getting squeezed down. And
24:48
Speaker 1: so if the aliens come and they squeeze the Sun
24:52
Speaker 1: into a tiny little black hole, then you know, who
24:55
Speaker 1: knows what's going on inside there, but nothing is coming out? Yeah? Wow,
24:59
Speaker 1: So it would be super weird, right because like if
25:03
Speaker 1: it happened right now, we wouldn't feel the difference right away,
25:07
Speaker 1: you know, like we would still be able to walk around.
25:09
Speaker 1: The Earth would still be spinning, we'd still be going
25:12
Speaker 1: in an orbit, but it just be like complete night
25:16
Speaker 1: all the time exactly. I mean we'd have great we
25:19
Speaker 1: do with great astronomy for a while, right until we
25:21
Speaker 1: ran in a power and food exactly. Yeah, no light,
25:28
Speaker 1: no heat right, Um, that would be pretty bad. And
25:31
Speaker 1: we rely on the Sun for a lot of stuff.
25:33
Speaker 1: You know. It fascinating to me though I didn't realize
25:35
Speaker 1: until recently that life on Earth didn't start in a
25:39
Speaker 1: way that was taking advantage of the sun. Right. Photosynthesis
25:42
Speaker 1: took a while to develop, like you know, hundreds of
25:45
Speaker 1: millions of years, so very very early life on Earth
25:48
Speaker 1: didn't rely directly on the Sun the way all life
25:51
Speaker 1: on Earth are almost all life and Earth currently does
25:54
Speaker 1: it relied on like geo thermal energy, right, energy from
25:57
Speaker 1: the heat of the Earth. Yeah, exactly. So there might
26:00
Speaker 1: be other sources of energy you could tap into. You
26:02
Speaker 1: have to drill down into the earth and and find
26:05
Speaker 1: some warmth there, um, but it would be pretty dismal.
26:09
Speaker 1: Your teslas certainly wouldn't be running very long. You could
26:11
Speaker 1: get energy maybe from the center of the Earth, right
26:15
Speaker 1: and power up lamps to grow your vegetables. Would that
26:18
Speaker 1: be possible. That would be possible, Yeah, but not for
26:22
Speaker 1: feeding billions of people. I mean, we have a huge
26:24
Speaker 1: fusion reactor out there in the center of the solar
26:26
Speaker 1: system just just pumping out energy, and we're just psiphing
26:30
Speaker 1: off a tiny little fraction of it to grow all
26:32
Speaker 1: of our plants to feed all of our people, um.
26:35
Speaker 1: And so we lose that. We do not have something
26:37
Speaker 1: that we can just like slot into place. We don't
26:39
Speaker 1: have a backup star, you know, a backup source of
26:42
Speaker 1: energy that can replace the Sun. Not yet. In fact,
26:45
Speaker 1: we're getting more and more reliant on solar energy because
26:48
Speaker 1: because we treat it as a renewable source of energy.
26:51
Speaker 1: And so I read recently that like now in the
26:54
Speaker 1: US at least or in Texas even um wind and
26:57
Speaker 1: solar power are providing war energy than coal. Right, coal
27:02
Speaker 1: is stored energy. We're digging up from the earth. Well,
27:05
Speaker 1: which is good news, right, it is good news. Of course,
27:09
Speaker 1: the hand of God comes down and smells out the sun,
27:12
Speaker 1: which the people in Texas um. You know, I don't
27:16
Speaker 1: know where I'm going. I don't know either, but I
27:18
Speaker 1: don't know where this podcast is going because it sounds
27:20
Speaker 1: like we're sort of promoting coal as backup for alien
27:23
Speaker 1: invasion or something. I'm not sure. Yeah, yeah, Just to
27:27
Speaker 1: be clear, we don't expect the hand of God or
27:30
Speaker 1: aliens to turn our son into a platform anytime. So
27:34
Speaker 1: it's all those solar panels that is probably the best
27:37
Speaker 1: thing for us right now. Yes, exactly. We are just
27:40
Speaker 1: exploring crazy hypotheticals in today's podcast. We are not giving
27:44
Speaker 1: you survivalist advice. We're going to be on the cover
27:47
Speaker 1: of Coal magazine, scientists come out in favor of coal.
27:52
Speaker 1: There we go, you're the one percent, Daniel Um. And
27:56
Speaker 1: you know, there's other interesting things like you get no
27:58
Speaker 1: more light from the sun, you get no more heat
28:00
Speaker 1: from the sun. You also there'll be no more solar radiation,
28:04
Speaker 1: which means like no solar wind. And the solar wind
28:07
Speaker 1: is these charge particles that come off of the Sun.
28:09
Speaker 1: You know, also a product of fusion that give you
28:12
Speaker 1: things like you know, the Northern lights, and so not
28:16
Speaker 1: only would we have night all the time, but we
28:18
Speaker 1: wouldn't even have you know, cool fancy glowing lights in
28:21
Speaker 1: the North and South Pole. Although I feel like that
28:23
Speaker 1: would be the least of our worries, you know, if
28:26
Speaker 1: the sun went out. If the sun went out, yeah,
28:28
Speaker 1: but you know, um, I figure at least you'd be
28:31
Speaker 1: able to have great night camping. But you know, all right,
28:33
Speaker 1: well it sounds like it wouldn't if the Sun turned
28:36
Speaker 1: into a black hole. You know, it wouldn't be a
28:39
Speaker 1: total collapse of humanity right away, right, Things would sort
28:43
Speaker 1: of still keep going. But eventually, Um, having no sun
28:46
Speaker 1: would be bad news for other reasons other than physics.
28:49
Speaker 1: That's right. If the sun went black hole. You wouldn't
28:52
Speaker 1: die in the way you might have expected, but you
28:54
Speaker 1: almost certainly will. I don't that's something that's right. But
29:01
Speaker 1: we don't expect the Sun to become a black hole.
29:03
Speaker 1: And though we do expect the Sun to expend its
29:06
Speaker 1: fuel and end its life as a cozy white dwarf,
29:09
Speaker 1: that also won't happen for billions of years. And so
29:12
Speaker 1: none of this is a reason to forget the very
29:15
Speaker 1: real ways in which we, we humans, might extinguish ourselves
29:19
Speaker 1: or destroy our planet by worrying about crazy, hypothetical astronomical
29:24
Speaker 1: problems that are very unlikely to bother us. But I
29:27
Speaker 1: think it's it's sort of tells you a little bit
29:29
Speaker 1: about how physics works, you know. It's sort of interesting
29:32
Speaker 1: to think that even if something like this happened, a
29:35
Speaker 1: lot of physics would just still keep going. Yeah, physics
29:38
Speaker 1: never quits, right and just keeps chugging along. All right. Well,
29:42
Speaker 1: we hope you enjoyed that discussion didn't get to alarm,
29:44
Speaker 1: and please remember to still get those solar panels um
29:49
Speaker 1: and that wind energy. Please, that's right. And if you
29:52
Speaker 1: are the aliens listening to this podcast, please don't turn
29:55
Speaker 1: the sun into a black hole. We need it all right, Well,
29:58
Speaker 1: thanks for listening. We go to joined that. And if
30:00
Speaker 1: you have questions about weird things that might be out
30:03
Speaker 1: there in the universe, weird things that might happen to
30:05
Speaker 1: our planet, please send us an email to Questions at
30:09
Speaker 1: Daniel and Jorge dot com. We love your questions, crazy
30:13
Speaker 1: or not, hypothetical or conceptual. See you next time. If
30:24
Speaker 1: you still have a question after listening to all these explanations,
30:27
Speaker 1: please drop us a line. We'd love to hear from you.
30:30
Speaker 1: You can find us at Facebook, Twitter, and Instagram at
30:34
Speaker 1: Daniel and Jorge That's one word, or email us at
30:37
Speaker 1: Feedback at Daniel and Jorge dot com. Thanks for listening,
30:41
Speaker 1: and remember that Daniel and Jorge Explain the Universe is
30:43
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