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Do fission reactors occur naturally? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, or hey, where do you get all your energy from?
0:11
Speaker 1: What do you mean? Well, you know you do this podcast,
0:14
Speaker 1: we write books, you run a TV show, you survive
0:17
Speaker 1: as a parent. What powers all of that activity? Fear? Maybe? Now,
0:21
Speaker 1: mostly it's just it is that it really just been
0:24
Speaker 1: in this. There's no other secret sauce you think I
0:27
Speaker 1: have like an arc reactor in my chest like Iron Man.
0:30
Speaker 1: It does seem like a superhuman level of activity. Sometimes
0:33
Speaker 1: should be a Marvel character like Nanimate procrasta man Now,
0:38
Speaker 1: I like Vnanim. I'll contact Marvel. I'll tell him it's
0:41
Speaker 1: very appealing, all right, I hope they don't slip up.
0:59
Speaker 1: Hi I am or am a cartoonists and the creator
1:01
Speaker 1: of PhD comics. Hi, I'm Daniel. I'm a particle physicist
1:04
Speaker 1: and a professor at u C Irvine where we have
1:07
Speaker 1: a working nuclear reactor. Oh my goodness. Is this out
1:11
Speaker 1: of your garage or like in your office or do
1:14
Speaker 1: you have an actual lab? No, under the chemistry building
1:17
Speaker 1: there is a functioning nuclear reactor which you can go
1:20
Speaker 1: and visit and like glows blue and everything. Is that
1:23
Speaker 1: a good idea to put it under? Like a campus
1:25
Speaker 1: full of thousands of kids? Well, I don't know, but
1:28
Speaker 1: we weren't going to put it under the physics building.
1:29
Speaker 1: That's why it ended up under the chemistry building. Oh,
1:32
Speaker 1: I see, the chemistry people are more expendable. I didn't
1:36
Speaker 1: say that. I'm just happy to not have it in
1:38
Speaker 1: my building. They're just danser and can absorb all of
1:40
Speaker 1: the you know, particles that come out. But it's pretty
1:43
Speaker 1: cool to visit and to like imagine all those crazy
1:46
Speaker 1: particle things happening right down in there. But anyways, welcome
1:49
Speaker 1: to our podcast, Daniel and Jorge Explain the Universe, a
1:51
Speaker 1: production of I Heart Radio in which we do get
1:54
Speaker 1: right down in there. We talk about all of the crazy,
1:57
Speaker 1: amazing things that are really happening out there in the universe.
2:01
Speaker 1: This chaotic buzz of insanity which is reality, is the
2:05
Speaker 1: subject of the podcast and the thing that we try
2:08
Speaker 1: to explain, and we shy away from none of it,
2:10
Speaker 1: from the tiniest little things to the hugest, vastest mysteries
2:14
Speaker 1: of the deepest cosmos. We attack all of it and
2:17
Speaker 1: explain all of it to you. That's right, because the
2:20
Speaker 1: universe sort of doesn't sleep. There's always something going on
2:22
Speaker 1: in the universe, making energy exploding and crashing into each other.
2:26
Speaker 1: And it's amazing to think about the idea that we
2:28
Speaker 1: could one day understand all of it. That is a
2:31
Speaker 1: crazy idea I've never heard before, that the universe might
2:34
Speaker 1: even sleep, you know, like imagine if like all of
2:37
Speaker 1: physics went to bed at night and just like stopped
2:40
Speaker 1: happening to a nap, cosmic nap, like the universe take
2:46
Speaker 1: a break for a minute. Let us catch up. We're
2:48
Speaker 1: still figuring things out. I mean, that's what's going on
2:50
Speaker 1: inside of black holes. It's just you know where the
2:52
Speaker 1: universe goes to take a nap. Oh yeah, it's just
2:54
Speaker 1: like a Google where they have nap pods. This is
2:56
Speaker 1: where like particles can go to take a break. Finally,
2:59
Speaker 1: like these folk, time has been going for billions of
3:01
Speaker 1: years without stopping. Who take a load off? You think
3:04
Speaker 1: the universe needs a vacation or something. You think the
3:06
Speaker 1: universe is tired. It seems to be pretty active and
3:09
Speaker 1: picking up on energy with its expansion. That's true. The
3:12
Speaker 1: universe does seem relentless, and so there's a lot going
3:15
Speaker 1: on in the universe, and sometimes we wonder how does
3:19
Speaker 1: all this energy go out into the universe? That's right,
3:21
Speaker 1: because all the stuff around us contains an incredible amount
3:25
Speaker 1: of energy. All the matter around you are these tiny
3:28
Speaker 1: little systems bound together with incredibly strong forces, which, if
3:32
Speaker 1: manipulated in just the right way, can release them in
3:35
Speaker 1: incredible bursts of energy. Yeah, and somehow, throughout the years,
3:39
Speaker 1: humans have figured out how to sort of take advantage
3:41
Speaker 1: of this idea of releasing the energy that stored inside
3:45
Speaker 1: of the bonds of the things that make up the universe,
3:47
Speaker 1: and sometimes for good reasons, and sometimes for not so
3:50
Speaker 1: great reasons. That's right. And you can see around you
3:53
Speaker 1: in the night sky, for example, fusion reactions happening that
3:57
Speaker 1: last millions and billions of years. At the heart of stars,
4:00
Speaker 1: of course, is a kind of a nuclear reactor. Down
4:04
Speaker 1: here on Earth. We don't see that as often, thankfully,
4:07
Speaker 1: but we've been able to sort of engineer similar stuff
4:10
Speaker 1: happening so we can take advantage of it and empower
4:13
Speaker 1: our air conditioners. Yeah, anytime that you hear a pop
4:17
Speaker 1: out in your daily life, it's probably some sort of
4:20
Speaker 1: chemical bond breaking up and releasing energy out into the world.
4:24
Speaker 1: Does that happen to you a lot? You just like
4:25
Speaker 1: turn around and hear something pop. Isn't that what happens
4:29
Speaker 1: every time you hear a car running? I have an
4:31
Speaker 1: electric car now, so it's totally silent. Oh interesting. Now
4:35
Speaker 1: you can sneak up on people. That's exactly why I
4:38
Speaker 1: got it. I can sneak up on them and like
4:40
Speaker 1: steal a look of their ice cream code or something.
4:42
Speaker 1: Oh my god, that is a little disturbing. You're like
4:46
Speaker 1: the ice cream bandit, the electric ice cream bandit. I've
4:49
Speaker 1: never actually done that, but now every time I'm gonna
4:51
Speaker 1: get in my car, I'm going to think about maybe
4:53
Speaker 1: doing that. But yeah, it's sort of an interesting idea
4:55
Speaker 1: to think about the humans sort of harnessing this power
4:58
Speaker 1: of this ability to kind of really the energy inside
5:01
Speaker 1: of everyday matter, right. I guess we started it with fire.
5:04
Speaker 1: Fire maybe was the first sort of maybe you know,
5:06
Speaker 1: chemical energy causing reaction that we came up with. Yeah.
5:09
Speaker 1: I think about it as if matter is like a
5:11
Speaker 1: bunch of tiny little springs bound together, and if you
5:14
Speaker 1: find just the right way to release those springs, you
5:16
Speaker 1: can capture all that energy and use it for something else.
5:19
Speaker 1: And exactly, fire is just that there are chemical bonds
5:22
Speaker 1: stored within the carbon and the other elements within wood,
5:25
Speaker 1: for example, and heat will release them in this chain reaction.
5:29
Speaker 1: That's the magic, where some energy is released and then
5:31
Speaker 1: it causes the neighbors to release their energy, which causes
5:34
Speaker 1: the neighbors to release their energy. And that's the magic,
5:37
Speaker 1: because you don't want to release the energy of just
5:39
Speaker 1: like one atom. Yeah, and so we figured out fire,
5:42
Speaker 1: and then eventually humans invented I guess it explosives and
5:46
Speaker 1: gasoline and engines and and so we're pretty good, it
5:49
Speaker 1: seems at kind of releasing that energy, at least the
5:52
Speaker 1: chemical kind. Yeah, we are. And all these things so
5:55
Speaker 1: far also happened in nature, right, Like fire is started
5:59
Speaker 1: by lightning, and most of the chemical chain reactions that
6:03
Speaker 1: humans have taken advantage of you can also see happening
6:06
Speaker 1: in nature. Yeah, and eventually we were able to harness
6:09
Speaker 1: the energy inside of atoms, right, I mean, we've figured
6:12
Speaker 1: out fusion and fission for both reactors and bombs, that's right.
6:17
Speaker 1: And I actually grew up in the town where the
6:18
Speaker 1: bombs were invented, in Los Almos. So this, like capturing
6:23
Speaker 1: the power at the heart of an atom, is sort
6:24
Speaker 1: of essential theme to my childhood. There's a certain glow
6:27
Speaker 1: about new Daniel. No, that's all the plutonium aid as
6:32
Speaker 1: a child. I see that's different. All right, Well, um, yeah,
6:36
Speaker 1: we made fusion and fission bombs. And as you were saying, Daniel,
6:38
Speaker 1: fusion happens a lot in nature. It happens naturally every
6:41
Speaker 1: time there's a sun, and every time you look out
6:44
Speaker 1: into the night sky, each one of those stars is
6:46
Speaker 1: a fusion reactors. There's basically an ongoing fusion bomb at
6:50
Speaker 1: each one of those pinpoints in the sky. That's right.
6:52
Speaker 1: It's awesome because it's a fusion bomb into continuous explosion
6:55
Speaker 1: that's also held in place by gravity. So it's like
6:59
Speaker 1: a stable reaction, which you know we've discovered is not
7:02
Speaker 1: that easy to engineer, but the universe has done it.
7:05
Speaker 1: It's amazing to me that stars exist and that they
7:07
Speaker 1: last for so long. Yeah, definitely, this night sky would
7:11
Speaker 1: be a lot less prettier without fusion and stars in it.
7:14
Speaker 1: I mean, what would Van Go have painted in Starry Night,
7:17
Speaker 1: the Blackie Blackie Nights? Yeah? Yeah, So the stars are fusion,
7:21
Speaker 1: and so we know that happens out in nature a lot.
7:23
Speaker 1: But the fission is different than fusion, right, it's sort
7:25
Speaker 1: of the opposite of fusion, that's right. Fusion is when
7:28
Speaker 1: you squeeze together light nuclei to make heavier ones, like
7:33
Speaker 1: squeeze hydrogen together to make helium. But fission is when
7:36
Speaker 1: you start with something which is already big and heavy,
7:39
Speaker 1: like uranium or plutonium, and your crack it into smaller nuclei,
7:43
Speaker 1: which also releases energy. Right, And so fission is the
7:47
Speaker 1: one that I think maybe most people associate with nuclear
7:50
Speaker 1: power right here on Earth, that that humans have been
7:53
Speaker 1: able to engineer. Right. I think most nuclear power plants
7:57
Speaker 1: and the nuclear bombs that we've made, and the people
7:59
Speaker 1: were about our fission, right, that's right. All of the
8:02
Speaker 1: nuclear power plants are fission. We're working on fusion plants,
8:05
Speaker 1: but nobody's really made that work yet. Our nuclear weapons,
8:08
Speaker 1: and initially we're fission because it's simpler and easier to
8:11
Speaker 1: get to work, but then more recently they are fusion
8:14
Speaker 1: powered because there's much more destructive. Actually, some of our
8:17
Speaker 1: nuclear weapons are fission bombs that are used just to
8:20
Speaker 1: trigger a fusion reaction. So they're like fission and fusion.
8:23
Speaker 1: It's a fusion of fission and it's insane. It's like,
8:26
Speaker 1: how do you light a fusion bomb. You need a
8:28
Speaker 1: fission bomb just to get it going, just give it
8:31
Speaker 1: a little extra fuss. But yeah, I guess there's sort
8:34
Speaker 1: of this weird thing that you know, we can't quite
8:36
Speaker 1: make fusion power happen here on Earth, but it hadn't
8:39
Speaker 1: happening all over the universe. And but then we can
8:42
Speaker 1: make fission bombs and fission reactors here on Earth. We've
8:45
Speaker 1: gone pretty good at engineering those, but maybe don't quite
8:48
Speaker 1: see them out there in the universe as much. Yeah,
8:50
Speaker 1: fission reactors take really special conditions which you don't find
8:54
Speaker 1: out there in the universe. And it makes me wonder
8:56
Speaker 1: like our humans the only ones who are doing this
8:59
Speaker 1: are these react actions only happening in our laboratories. And
9:03
Speaker 1: so to be on the podcast, we'll be asking the
9:05
Speaker 1: question can a fission reactor happen naturally? And Daniel, this
9:14
Speaker 1: isn't one of those episodes where we actually like tell
9:16
Speaker 1: people how to make afficient bomb or something dangerous out there.
9:20
Speaker 1: It's not another one of those episodes, is it. No,
9:22
Speaker 1: this is not in the Supervillain how to series. Check
9:29
Speaker 1: out our YouTube series on how to become a super
9:31
Speaker 1: Villain using physics, So check out our lessons on our website.
9:35
Speaker 1: First adopt a white cat, second by a volcano. Shave
9:39
Speaker 1: your head? What you got to shave your head? I'm out,
9:42
Speaker 1: nothing's worth that. Let's be honest. We're almost at the
9:45
Speaker 1: battling stage anyway. Not me, I'm and I still have
9:48
Speaker 1: a vibrant head of hair, not a single gray It's
9:51
Speaker 1: all that plutonium. It's all that plutonium exactly. Yeah. But anyways,
9:55
Speaker 1: so I guess the question is, like, can we know
9:58
Speaker 1: that a fusion reactor happens naturally nature? It's on every
10:01
Speaker 1: at the center of every star. But the question is
10:02
Speaker 1: does a fission reactor happen naturally in the universe? Like,
10:05
Speaker 1: can you have a fission star even out there in space? Yeah,
10:09
Speaker 1: we actually did a whole episode about can you have
10:11
Speaker 1: stars that are run by fishing? That was a listener question,
10:14
Speaker 1: which is super awesome, and we decided it might be possible,
10:18
Speaker 1: but it was very unlikely to arrange the circumstances necessary.
10:22
Speaker 1: And what we'll discover in today's episode is that fission
10:25
Speaker 1: is delicate and you have to have just the right
10:28
Speaker 1: conditions arranged in just the right way at just the
10:30
Speaker 1: right time to make it happen, or you need clever
10:33
Speaker 1: human engineers. Well, it seems kind of weird to me, right,
10:36
Speaker 1: because it seems generally that it's easier to break things
10:39
Speaker 1: than it is to put them back together. So it's
10:41
Speaker 1: kind of weird to think that fission is sort of
10:43
Speaker 1: like rarer or harder to achieve. Yeah, that's true. All
10:46
Speaker 1: though the products that you need for fission, the heavy stuff,
10:49
Speaker 1: are generally more rare than the products you need for fusion,
10:52
Speaker 1: which is the light stuff. Like, remember, the universe still
10:55
Speaker 1: mostly hydrogen. We've been working at it for fourteen billion
10:58
Speaker 1: years and still most of the stuff in the universe
11:01
Speaker 1: is just what it started as, which is hydrogen. All right, Well,
11:04
Speaker 1: as usual, we were wondering how many people out there
11:06
Speaker 1: have thought about this question and knew whether nuclear fission
11:10
Speaker 1: reactors can happen in nature. So Daniel went out there
11:13
Speaker 1: into the Internet to ask people this question. So thank
11:16
Speaker 1: you denizens of the Internet for answering these questions. And
11:19
Speaker 1: if you are a denizen of the Internet and have
11:22
Speaker 1: not yet answered our questions, we want to hear your voice,
11:25
Speaker 1: especially if you have a super awesome, unusual, weird voice
11:28
Speaker 1: that people would like to listen to. But even if
11:30
Speaker 1: you don't and you like answering random questions, shoot us
11:33
Speaker 1: a note to questions at Daniel and Jorge dot com.
11:36
Speaker 1: Here's what people had to say. I don't think nuclear
11:39
Speaker 1: fission can occur naturally because you always hear about how
11:44
Speaker 1: lighter elements, for like fuse to form heavier elements, and
11:48
Speaker 1: that's how all the heavier elements in the universe have
11:51
Speaker 1: been formed. But you never hear anything about the opposite
11:54
Speaker 1: reverse and like there's no splitting, there's no creation of
11:59
Speaker 1: more sort of hydrogen that you hear of. My initial
12:03
Speaker 1: response was, yes, nuclear fission occurs in nature naturally, and
12:07
Speaker 1: it was just a trick from nature that we've copied.
12:11
Speaker 1: But on the other hand, I don't see nuclear bombs
12:15
Speaker 1: spontaneously going off in nature underground all the time, so
12:19
Speaker 1: maybe not. But I can also imagine that in high
12:23
Speaker 1: energy occurrences like a Supernovy or other I energy occurrences,
12:29
Speaker 1: stuff gets bombarded with neutrons and adams split. So I
12:37
Speaker 1: still have to go with yes, but I'm not totally certain.
12:40
Speaker 1: I would like to think so, but I think most
12:44
Speaker 1: nuclear fission that I know about is something man made,
12:47
Speaker 1: so maybe well, since we full split atoms in duicular, reactors.
12:53
Speaker 1: Um it sounds like gonna be a bit scary if
12:55
Speaker 1: it happened anywhere on Earth naturally. Yes, I believe it can.
12:59
Speaker 1: I think there's an example of it having happened to
13:04
Speaker 1: something billion years ago in continental Africa somewhere. I don't
13:11
Speaker 1: know of any other examples, but I believe it can
13:13
Speaker 1: happen naturally. Quite sure that the strong forces which I'm
13:19
Speaker 1: pretty sure keeps those nuclear together, some electrom and egg
13:22
Speaker 1: forces keeping it together, that they would take a lot
13:25
Speaker 1: to oppose that. So I'm thinking maybe in some sort
13:28
Speaker 1: of extreme gravity situation. But but still I still think
13:34
Speaker 1: it's nuclear too small and the strong forces too strong
13:37
Speaker 1: too to have some sort of nuclear fission occur naturally.
13:41
Speaker 1: I think it's naturally. I don't know how to explain it,
13:45
Speaker 1: and I don't know how. I do not know if
13:48
Speaker 1: nuclear fission occurs naturally, but I assume it does because
13:54
Speaker 1: the vast quantities of different elements the universe has so
14:00
Speaker 1: sure what's happened before in the universe all right on
14:05
Speaker 1: the whole, it seems like most people thought that yes,
14:07
Speaker 1: the answer was yes, that you can have fission out
14:09
Speaker 1: there in nature happened naturally. Yeah, And I think this
14:12
Speaker 1: is motivated by the general feeling that like, wow, it's
14:15
Speaker 1: a big universe, and everything you imagine might happen is
14:18
Speaker 1: probably out there happening somewhere. They've heard our podcast so
14:22
Speaker 1: much that now they just assume that anything that sounds
14:25
Speaker 1: crazy is happening somewhere, at least in one spot in
14:28
Speaker 1: this infinite universe. And it's a good motivation, you know.
14:31
Speaker 1: After physicists take advantage of that all the time. They
14:34
Speaker 1: can't like do experiments like what happens when two neutron
14:37
Speaker 1: stars collide. You can't build a neutron star collider. So
14:40
Speaker 1: you just look out in the universe and say, hey,
14:42
Speaker 1: let's watch and see if we spotted happening, and then
14:45
Speaker 1: we can do our experiment effectively. Yeah, so I guess them,
14:48
Speaker 1: why do you Why do we even need to hire you, Daniel?
14:51
Speaker 1: Somebody's got to eat the plutonium man. Yeah, somebody's gonna
14:55
Speaker 1: make the banana jokes. All right. So let's talk about
14:57
Speaker 1: this question of whether or not nuclear fish in reactors
15:01
Speaker 1: can happen naturally out there in the universe. And so,
15:04
Speaker 1: first of all, I guess let's step through it in
15:05
Speaker 1: more detail. What is nuclear fission. So fission is when
15:10
Speaker 1: you break up heavy nuclei into smaller atoms. So everything
15:15
Speaker 1: above iron, everything that's heavier than iron, that has more
15:19
Speaker 1: protons in the nucleus than iron, if you're cracking in half,
15:23
Speaker 1: then you release energy and you make two smaller nuclei, right,
15:27
Speaker 1: Because I guess all matter, all the stuff we're made
15:29
Speaker 1: out of, is made out of atoms, and an atom
15:32
Speaker 1: is in nucleus with electrons flying around it, and so
15:35
Speaker 1: the only difference between like uranium and carbon is just
15:38
Speaker 1: how much stuff is in the nucleus, right, which is
15:40
Speaker 1: just protons and neutrons exactly. And the thing that defines
15:43
Speaker 1: an element is the number of protons in itsel If
15:46
Speaker 1: you add a proton, you change the charge because protons
15:49
Speaker 1: are charged, and then you need another electron, and that
15:52
Speaker 1: changes the fundamental chemical reactions that it can be involved in.
15:55
Speaker 1: Is that changes sort of the identity of it. And
15:58
Speaker 1: you can add neutrons if you like. New strons are neutrals,
16:00
Speaker 1: so they don't take change to charge and don't require
16:02
Speaker 1: another electron, but it does give you another isotope. And
16:05
Speaker 1: as you add protons and neutrons, things get heavy, and
16:08
Speaker 1: there are some arrangements that are stable, they can hang
16:11
Speaker 1: out basically forever. But there are lots of these arrangements
16:14
Speaker 1: which are not stable, which will eventually just sort of
16:17
Speaker 1: break up on their own. We had a whole fun
16:20
Speaker 1: podcast about really heavy elements and which ones are stable
16:23
Speaker 1: and which ones are not stable, which you can check
16:25
Speaker 1: out if you're interested in the nuclear physics of it.
16:27
Speaker 1: So I guess that you're saying the identity of atoms
16:30
Speaker 1: has all everything to do with the protons in it.
16:32
Speaker 1: So like hydrogen just has one proton in the middle,
16:35
Speaker 1: but uranium has like two five protons, typically hundreds of
16:40
Speaker 1: protons in the nucleus. Uranium has ninety two protons in it,
16:44
Speaker 1: but it occurs in nature in a couple of different isotopes.
16:47
Speaker 1: Uranium two thirty five or two thirty five refers to
16:51
Speaker 1: the number of protons and neutrons together, So if you
16:55
Speaker 1: do some quick math, you can discover uranium two thirty
16:57
Speaker 1: five has nine two protons and a hundred and forty
17:02
Speaker 1: three neutrons stuffed into it. And it's also uranium two
17:06
Speaker 1: thirty eight, which comes with three more neutrons, and so
17:10
Speaker 1: most of the uranium out there is you two thirty eight,
17:12
Speaker 1: which is much more stable. You two thirty five is
17:15
Speaker 1: more rare and much more useful actually for fission, right, right,
17:20
Speaker 1: And but you know they're not as good as you two.
17:22
Speaker 1: I think they've been working on it for a lot
17:24
Speaker 1: longer though, still waiting to have that breakthrough album. There
17:27
Speaker 1: are a lot more heavy metal. Maybe there are no
17:29
Speaker 1: hit wonder now I'm just kidding, I think. I think
17:31
Speaker 1: what you're saying is that, you know, uranium has ninety
17:34
Speaker 1: two protons and i'm a whole bunch of neutrons, and
17:36
Speaker 1: it's sort of like legos, right, Like you can just
17:38
Speaker 1: add these building blocks and you get different atoms, which
17:41
Speaker 1: means at some point you could potentially break them apart
17:44
Speaker 1: to get two of the lighter elements, right, yeah, exactly,
17:48
Speaker 1: You break up that nucleus, and then you share those protons,
17:52
Speaker 1: those n protons between the products, and so you get
17:55
Speaker 1: things made out of smaller numbers of protons. Yeah, And
17:58
Speaker 1: so that's a fission action. That's nuclear fission, that's right.
18:01
Speaker 1: And nuclear fission mostly we do it with uranium two
18:04
Speaker 1: thirty five and sometimes with plutonium two thirty nine, where
18:08
Speaker 1: again the number is the total number of protons and
18:11
Speaker 1: neutrons together, and so in most nuclear reactors that generate power,
18:15
Speaker 1: you have either uranium two thirty five or plutonium two
18:18
Speaker 1: thirty nine, all right, And so somehow breaking up the
18:21
Speaker 1: inside of an atom, the nucleus of an atom into
18:24
Speaker 1: smaller elements, somehow that crew releases a whole bunch of energy, right,
18:28
Speaker 1: which is kind of weird to think about if you
18:30
Speaker 1: think about it, right, like, why would breaking something release energy? Yeah, Well,
18:34
Speaker 1: because there's energy stored in there. You know, you can
18:37
Speaker 1: imagine if you like mechanical analogies, you can imagine like
18:40
Speaker 1: that they're stored in there with a bunch of springs
18:42
Speaker 1: that are really tautly wound together, and when you break it,
18:46
Speaker 1: what happens is that the springs release and they shoot
18:48
Speaker 1: the parts out, and there's parts are now moving really
18:51
Speaker 1: really fast. So the energy that was stored in that
18:53
Speaker 1: spring has now been transformed into the motion of the
18:57
Speaker 1: particles that are flying out. And that's essentially it's happening here,
19:00
Speaker 1: except instead of having like literal springs, you have gluons,
19:04
Speaker 1: the carriers of the strong force that are tying these
19:07
Speaker 1: things together. There's a lot of energy in those bonds,
19:10
Speaker 1: and when you break it up, that energy is released
19:12
Speaker 1: and the particles come out moving really quickly. I guess
19:15
Speaker 1: maybe it might help if we maybe talked a little
19:17
Speaker 1: bit about what's actually going on. Like if I break
19:19
Speaker 1: a banana and two or if I break my cell
19:21
Speaker 1: phone or something like, I don't get a lot of
19:23
Speaker 1: energy getting released, right, Like, things are breaking and bonds
19:26
Speaker 1: are breaking, but there's not a lot of like where
19:28
Speaker 1: does that energy come from? Actually, yeah, well, if you
19:30
Speaker 1: do break a banana and half or you break your
19:32
Speaker 1: cell phone and half, you are breaking bonds. Those are
19:35
Speaker 1: chemical bonds, right, Those are bonds between atoms, and the
19:38
Speaker 1: atoms are not changing. You might be taking a molecule
19:40
Speaker 1: and breaking into its atoms, or you might be just
19:43
Speaker 1: sort of like cracking a crystal a long you know,
19:46
Speaker 1: a part of its lattice, and so their bonds between
19:49
Speaker 1: molecules that are being released. But you don't notice any
19:52
Speaker 1: energy being released there because the energy is really really small.
19:55
Speaker 1: But when you break a nucleus in half, then the
19:57
Speaker 1: energy released is huge and the and it's much bigger.
20:00
Speaker 1: It's because the strong forces involved in the strong force
20:03
Speaker 1: as well, it's really strong and so it has a
20:05
Speaker 1: lot of energy stored inside these atoms. It's much stronger
20:09
Speaker 1: than the electromagnetic force, which is one that's holding your
20:12
Speaker 1: banana or your cell phone together. I guess it's kind
20:15
Speaker 1: of like you say that, like there's a spring holding
20:17
Speaker 1: these these nuclear particles together, and so suddenly if you
20:20
Speaker 1: like detach those springs, they're gonna spring out, right, all
20:23
Speaker 1: that sort of stretched energy has to go somewhere. Yeah,
20:25
Speaker 1: it's sort of like a jack in the box, right,
20:27
Speaker 1: and you open the top and boom, everything pops out.
20:30
Speaker 1: Or it's like you know, one of those cans full
20:31
Speaker 1: of snakes, so you open it up and like bang,
20:34
Speaker 1: everything flies out. And and that's exactly what happens here.
20:37
Speaker 1: You crack open the nucleus it was held together sort
20:40
Speaker 1: of delicately. You crack it open and everything flies out
20:43
Speaker 1: with a bunch of energy. But it's sort of like
20:44
Speaker 1: a reverse jack in the box, right, because the springs
20:46
Speaker 1: are pulling stuff together, not sort of being compressed and
20:50
Speaker 1: wanting to explode. Yeah, exactly here in this case, the
20:53
Speaker 1: bonds are holding them together, so they're sort of trapped
20:55
Speaker 1: in a bound state where the bonds you know, have
20:58
Speaker 1: a potential, well, where everything like trapped inside You can
21:02
Speaker 1: think of that sort of as like the box that's
21:04
Speaker 1: holding the jack in the box together, or they can
21:06
Speaker 1: that's holding the snakes inside. But inside there are things
21:10
Speaker 1: with a lot of energy that are desperate to get out.
21:12
Speaker 1: They're trapped into a stable configuration currently, but if you
21:16
Speaker 1: destroy the barriers that are holding them in, they will
21:18
Speaker 1: fly out. I wonder if it's like, you know, wrapping
21:21
Speaker 1: something up in bungee cords and holding this time some
21:24
Speaker 1: something big together with bungee cords or rubber bands, and
21:26
Speaker 1: then when you cut a rubber band, you know, it
21:29
Speaker 1: snaps and they go flying out. Yeah, exactly, Take a
21:31
Speaker 1: huge ball of rubber bands and cut it in half
21:34
Speaker 1: with a circular saw. Then the rubber bands are going
21:36
Speaker 1: to go everywhere, and they're not just gonna lie down
21:38
Speaker 1: nicely on the table. All right, Well, that's nuclear fishing.
21:41
Speaker 1: That's what happens when fission happens in an atom. And
21:44
Speaker 1: so let's get into whether or not it happens naturally
21:48
Speaker 1: in nature and whether or not we've ever seen it happen.
21:51
Speaker 1: But first let's take a quick break. We're talking about
22:06
Speaker 1: nuclear vision and how to make it at home, right, Daniel,
22:09
Speaker 1: With some simple ingredients. That's right. First call up the
22:13
Speaker 1: n s A and book your room because you're gonna
22:15
Speaker 1: be staying with them for a long time. Make sure
22:18
Speaker 1: you get a spot with the window. Oh man, I
22:19
Speaker 1: wonder if there are people from the n s A
22:21
Speaker 1: listening to us? Then is always listening, It's just not
22:25
Speaker 1: counted in our podcast listenership, which I don't think it's fair.
22:28
Speaker 1: I see right, right, we could have one more added
22:30
Speaker 1: to our data, unless they're listening to the ads, in
22:32
Speaker 1: which case, hey, it's all cool, it's all but yeah,
22:37
Speaker 1: we talked about vision and what it is. It's when
22:39
Speaker 1: you break up a heavy atom into lighter atoms, when
22:43
Speaker 1: you redistribute the number of protons in the nucleus. And
22:46
Speaker 1: so the question we're asking today is can that happen
22:48
Speaker 1: naturally in nature? And more specifically, can you like have
22:52
Speaker 1: a reactor of it that creates a bunch of energy
22:56
Speaker 1: happen in nature? Exactly because fission itself, like an atom
23:00
Speaker 1: aching into smaller pieces and releasing energy that happens all
23:03
Speaker 1: the time, like uranium just sitting around is unstable, and
23:07
Speaker 1: those atoms will crack and have and they will fly apart,
23:10
Speaker 1: and lots of atoms are unstable, and every time that
23:13
Speaker 1: happens you call it radioactive decay. It really is vision.
23:17
Speaker 1: But what we do inside of reactor is not just
23:18
Speaker 1: have like one atom break and half or two atoms
23:21
Speaker 1: break and half. We have something special. We have a
23:24
Speaker 1: chain reaction, a self sustaining reaction sort of like fire.
23:28
Speaker 1: That's very special arrangement which only in this century we
23:31
Speaker 1: were able to engineer to make happen. So you're saying that,
23:34
Speaker 1: like fission bitte self does happen in nature, like things
23:37
Speaker 1: break apart in nature all the time. But it's getting
23:39
Speaker 1: it to like be self sustaining and have it sort
23:42
Speaker 1: of be like a fire where it's constantly happening. That's harder.
23:46
Speaker 1: Or like did you see the sun for fusion, that's
23:48
Speaker 1: harder to do, Yeah, exactly. It's like the difference between
23:50
Speaker 1: having a spark and having a fire. You know, we've
23:53
Speaker 1: all been there at a campsite shooting sparks at something
23:56
Speaker 1: and trying to get a fire started. It's not always
23:58
Speaker 1: easy to get a fire. Star did right. You can
24:01
Speaker 1: have smarks, which are evidence of energy being released. Right,
24:04
Speaker 1: the same chemical process is at work, But to get
24:07
Speaker 1: a fire started, you need to get enough heat so
24:09
Speaker 1: that you're igniting more fuel, which can then release more heat,
24:13
Speaker 1: which can ignite more fuel. So it's a self sustaining part,
24:16
Speaker 1: which is quite tricky to happen even for fire, sometimes
24:20
Speaker 1: especially difficult for a fission chain reaction. So this happens
24:24
Speaker 1: in nature for fusion, like in the sun and the stars.
24:28
Speaker 1: That seems it seems to happen more easily for fusion
24:30
Speaker 1: than for fission. That's right, But again that's probably just
24:33
Speaker 1: because there is a lot of fuel for fusion around, right.
24:35
Speaker 1: Fusion requires light elements, and there are a lot of
24:38
Speaker 1: light elements in the universe. It's mostly hydrogen out there,
24:42
Speaker 1: and so that's fuel for fusion, all right. So you're
24:45
Speaker 1: saying that if fision, making fission happen constantly is hard,
24:49
Speaker 1: But we figured it out here on Earth right in
24:51
Speaker 1: our nuclear reactors and in our nuclear bombs. So how
24:54
Speaker 1: do how do we do it? So the key things
24:56
Speaker 1: you need to make a self sustaining fission reaction, you
24:59
Speaker 1: need to say things. One is you need enough fuel
25:02
Speaker 1: sort of close to each other, because you need one
25:04
Speaker 1: fission reaction to trigger the next one, which triggers the
25:08
Speaker 1: next one, right, sort of like if you're trying to
25:09
Speaker 1: start a fire, you don't spread your logs out everywhere.
25:12
Speaker 1: You get them close together so the heat from one
25:14
Speaker 1: can ignite the next one. And then you also need
25:17
Speaker 1: something to get the neutrons that fly out to be
25:20
Speaker 1: at the right speed, because the neutrons that fly out
25:23
Speaker 1: don't always come out at just the right speed to
25:25
Speaker 1: trigger the next reaction. So you need one a critical mass,
25:28
Speaker 1: and two you need this thing called a neutron moderator,
25:32
Speaker 1: which makes the neutrons go with just the right temperature. Yeah,
25:35
Speaker 1: those neutrons are not as neutral as they seem. Sometimes
25:38
Speaker 1: you get a pull it back. Sometimes well they're just
25:40
Speaker 1: so excited to get out there into the world and
25:42
Speaker 1: do something like Hey, neutron, look, let me give you
25:44
Speaker 1: some career advice. Okay, you don't want to burn out immediately,
25:47
Speaker 1: all right, So let's tackle each of these interns. So
25:50
Speaker 1: you say you need critical mass because in a chain
25:52
Speaker 1: reaction fission, In a fission chain reaction, you have like
25:56
Speaker 1: one atom splits open that releases a bunch of energy,
25:59
Speaker 1: and that energy comes out as particles I guess or photons,
26:03
Speaker 1: and then those hit other heavy nuclei which then causes
26:06
Speaker 1: them to break, and then those release more energy, which
26:09
Speaker 1: causes other things to break. So that's what you mean
26:11
Speaker 1: by chain reaction, right, Yeah, exactly. And what happens when
26:15
Speaker 1: you break up the uranium, for example, is you get
26:19
Speaker 1: the fragments, you get the like lighter elements, and then
26:22
Speaker 1: mostly you get neutrons. Like you get some energy in
26:25
Speaker 1: terms of photons, but then also you get these neutrons.
26:27
Speaker 1: And that's critical because it's the neutrons that are going
26:30
Speaker 1: to trigger the neighboring atoms to break apart. For example,
26:33
Speaker 1: you take a neutron and you shoot it into a
26:36
Speaker 1: uranium atom, and it will make it unstable. It will
26:39
Speaker 1: give it enough energy so that instead of being like
26:42
Speaker 1: a nicely built piece of lego, it's like a little
26:45
Speaker 1: wobblie and then it's going to break open. And so
26:48
Speaker 1: it's the neutron that triggers the reaction in the neighbor Interesting,
26:52
Speaker 1: so I guess, first of all, when a atom breaks apart,
26:55
Speaker 1: why does it release a lot of neutrons and not
26:57
Speaker 1: like protons or something else. Yeah, actually shoots out a
27:00
Speaker 1: bunch of particles. And so sometimes you get neutrons, sometimes
27:03
Speaker 1: you get gamma rays, you can also get protons. Mostly
27:06
Speaker 1: the protons like the cluster together into these other nuclei,
27:09
Speaker 1: so we call these nuclear fragments. They go off and
27:12
Speaker 1: form little daughter particles. But you can sometimes get protons out,
27:15
Speaker 1: and also the neutrons that you shoot out, they will
27:18
Speaker 1: eventually decay because neutrons are not stable, so you will
27:21
Speaker 1: eventually get protons coming out also. All right, so you're
27:24
Speaker 1: saying that's pretty interesting, because that's one thing I didn't
27:26
Speaker 1: know is that I always thought that when fishing reactions happen,
27:28
Speaker 1: it's like the energy from the shooting particles break the
27:32
Speaker 1: other ones in part, but it's really more like you're
27:34
Speaker 1: shooting off hairs and they break the camel back of
27:37
Speaker 1: other Yeah, it's like little bullets, right. These neutrons are
27:41
Speaker 1: like little bullets, and they're shooting out and they have
27:43
Speaker 1: just the right interactions to mess up the neighbors. And
27:46
Speaker 1: so it's sort of like you know, divorces spreading throughout
27:49
Speaker 1: a friend group. You know, people get grumpy, they get divorced,
27:53
Speaker 1: they start complaining to their friends about their marriages, and
27:55
Speaker 1: their friends are like, oh, that sounds familiar, maybe we
27:58
Speaker 1: should get divorced. Yeah, it's like I was saying, it's
28:00
Speaker 1: like it's shooting hairs that break the camel's backs all around,
28:02
Speaker 1: and then when those camels break apart, that shoots off
28:05
Speaker 1: hairs that break other camel backs, right exactly. And so
28:08
Speaker 1: what you need is a critical mass. When those neutrons
28:10
Speaker 1: fly out of the fission ing atom, they need something
28:14
Speaker 1: to hit, and so you need to have enough fuel
28:16
Speaker 1: sort of packed densely together in order to make it
28:19
Speaker 1: so that you can have a self sustaining reaction. And
28:22
Speaker 1: critical mass is probably like a phrase you've heard before,
28:24
Speaker 1: and that's essentially the most important component and having a
28:27
Speaker 1: nuclear reaction, right, because I guess if the camels are
28:30
Speaker 1: too far apart, you know, one of them will just
28:33
Speaker 1: break apart and send hairs flying up, but that the
28:35
Speaker 1: hairs won't hit the other camels, so you need them
28:37
Speaker 1: pack close together. I see that you prefer to talk
28:39
Speaker 1: about camels than divorces, but I'll go, yeah, it's a
28:43
Speaker 1: bit of a bummer camels that, you know, more fun image.
28:47
Speaker 1: Our camel's monogamous, by the way, do they meete for life? Yeah,
28:50
Speaker 1: let's talk about camel divorce. I'm just trying to fuse
28:54
Speaker 1: it all together rather than fission, our analogies into two
28:57
Speaker 1: different topics. Um any analogies for fission can we come
29:01
Speaker 1: up with? We've already broken bananas and jack in the
29:04
Speaker 1: box inverse jack in the boxes and camels and divorce.
29:09
Speaker 1: All right, so critical masks, we get a chain reaction
29:11
Speaker 1: of fission, and you also you need to slow down
29:14
Speaker 1: the neutron somehow. Yeah. The problem is that when the
29:16
Speaker 1: neutrons fly out, they have a lot of energy, so
29:19
Speaker 1: they're called fast neutrons. They're just moving really really quickly,
29:23
Speaker 1: and even if you pack your uranium pretty tightly, the
29:26
Speaker 1: neutrons that come out are moving too quickly to ignite
29:29
Speaker 1: the neighboring uranium nuclei into breaking because the faster they're going,
29:34
Speaker 1: the more the like the universe is compressed for them,
29:38
Speaker 1: and so they have a smaller chance of hitting those neighbors.
29:41
Speaker 1: So what you need is something to slow down those
29:43
Speaker 1: neutrons to just the right speed so they have a
29:46
Speaker 1: high enough chance of hitting a nucleus and triggering another
29:50
Speaker 1: reaction out. Interesting, it's about like the probability of hitting
29:54
Speaker 1: another atom, right, Like the hairs from the camel are
29:58
Speaker 1: flying off to fast, they'll just miss all the other camels.
30:02
Speaker 1: But if it's growing slow, then it's a bigger chance
30:04
Speaker 1: that you know, a camel will walk into the path
30:07
Speaker 1: of one of these hairs. Yeah, because you don't want
30:09
Speaker 1: your neutrons to fly all the way through your fuel
30:10
Speaker 1: and escape with their energy. You want them to deposit
30:13
Speaker 1: that energy in some other nuclei so you can trigger
30:17
Speaker 1: another reaction. So basically you have to make your fuel
30:19
Speaker 1: opaque to neutrons rather than transparent. And so to do that,
30:23
Speaker 1: you've got to slow them down because fast neutrons will
30:26
Speaker 1: escape and slow neutrons will be captured by neighboring atoms
30:30
Speaker 1: and trigger more reactions. All right, So you need critical
30:32
Speaker 1: mass and you need to slow down your neutrons, and
30:35
Speaker 1: if you do that, then you can get a efficient
30:37
Speaker 1: chain reaction to heaven. And that's what gives you nuclear
30:40
Speaker 1: bombs and nuclear reactors, that's right. That's mostly the designed
30:43
Speaker 1: for a nuclear reactor, not nuclear bomb. And so if
30:46
Speaker 1: you're a nice person out there and looking to build
30:49
Speaker 1: the next generation of nuclear reactors and provide clean, green
30:52
Speaker 1: energy to the future, then we support you. If you're
30:55
Speaker 1: out there trying to build a nuclear weapon, then you know,
30:58
Speaker 1: check out another podcast. You done here here you can
31:01
Speaker 1: basically turn this off. But this was first done in
31:05
Speaker 1: in Chicago by Enrico Fermi, and it's not an easy
31:08
Speaker 1: thing to accomplish. This right balance of having the right
31:11
Speaker 1: massive fuel and just the right sort of neutron moderator
31:15
Speaker 1: take of the neutrons at the right speed. It's really
31:17
Speaker 1: quite delicate. So that's how you make a nucleon fission reactor.
31:20
Speaker 1: And so now the question that we started with was
31:22
Speaker 1: does it occur naturally in nature? Are their stars out there?
31:26
Speaker 1: Are there things that are naturally reacting with fission constantly?
31:30
Speaker 1: So let's get into that question. But first let's take
31:32
Speaker 1: another quick break. All right, can a fish and reactor
31:48
Speaker 1: happened naturally on this universe? Daniel? I guess the question
31:53
Speaker 1: is is there somehow, you know, like we see stars
31:56
Speaker 1: out there that are constant fusion reactors? Do we see
32:00
Speaker 1: and I don't know, some weird concentration of uranium or
32:03
Speaker 1: plutonium that is constantly also reacting and giving off energy? Yeah, well,
32:08
Speaker 1: what you need are both of the elements, right, You
32:10
Speaker 1: need some critical mass of uranium or plutonium, and you
32:14
Speaker 1: need something to moderate the reaction so that it can
32:17
Speaker 1: self sustain rather than just like burning itself out by
32:20
Speaker 1: shooting these neutrons out and losing all of their energy.
32:23
Speaker 1: And so in our episode about fission stars, I think
32:26
Speaker 1: we concluded that there isn't enough uranium in the universe
32:30
Speaker 1: to make like dense blobs of uranium that could do that.
32:33
Speaker 1: But you know, there are deposits of uranium here in
32:37
Speaker 1: the crust of the Earth surface, and so you can imagine, like, hmm,
32:40
Speaker 1: could there like just like happen to be really rich
32:43
Speaker 1: deposits of uranium in the Earth surface and just the
32:46
Speaker 1: right arrangement to somehow like create natural fission reactors, right,
32:51
Speaker 1: because I guess you could get a chain reaction going
32:53
Speaker 1: with any amount of uranium, but I guess if you
32:55
Speaker 1: only have like a teaspoon of it, it won't last
32:57
Speaker 1: very long. Right, So you're saying, like maybe here on
32:59
Speaker 1: Earth we could have enough uranium together that we do
33:04
Speaker 1: get this sort of nuclear constant reaction going exactly. And
33:07
Speaker 1: this is something that in nineteen fifty six a business
33:10
Speaker 1: was thinking about. It is Paul Kuroda, and he predicted
33:13
Speaker 1: that it would be possible. He said, if you have
33:15
Speaker 1: a configuration in the Earth's crust where you have exactly
33:19
Speaker 1: the right amount of uranium in the right configuration, and
33:22
Speaker 1: like water leaks in and provides just the right kind
33:26
Speaker 1: of like neutron moderation, then you could get a nuclear
33:29
Speaker 1: reaction going just like by itself spontaneously underground. I guess
33:34
Speaker 1: I'm surprised that it doesn't happen more often. Is it
33:36
Speaker 1: the case that you know, we have a lot of
33:38
Speaker 1: uranium here on Earth and it's it's fission ng, it's
33:41
Speaker 1: breaking up apart, but it's not causing a chain reaction,
33:44
Speaker 1: so it's not sort of like burning up really quickly.
33:46
Speaker 1: That's exactly right. Uranium just sitting around is constantly fissioning
33:51
Speaker 1: and constantly breaking up, and sometimes it's even in critical mass.
33:55
Speaker 1: But there's not a neutron moderator, and so you need
33:57
Speaker 1: that second piece to make these elf sustaining reaction happen. Well,
34:02
Speaker 1: and so that's happened here on Earth. So someone predicted it.
34:04
Speaker 1: But have we found an actual like natural fission reactor
34:08
Speaker 1: on Earth. Yes, Actually, somebody has figured out that billions
34:12
Speaker 1: of years ago deposits in the earth in Gabon in
34:16
Speaker 1: the African continent did experience a nuclear self reaction. Basically,
34:21
Speaker 1: there was a reaction happening underground on Earth, and the
34:25
Speaker 1: way they discovered is really quite a fun story what happened.
34:28
Speaker 1: Uranium is a very special and important material, right, and
34:31
Speaker 1: we don't want the wrong people to get their hands
34:34
Speaker 1: on it, so people do very careful accounting of like
34:37
Speaker 1: the amount of uranium. Remember that uranium comes into flavors.
34:40
Speaker 1: There's the U two thirty five, which is the important
34:43
Speaker 1: one you need for doing fission, and then there's U
34:45
Speaker 1: two thirty eight, which is much longer lasting and much
34:48
Speaker 1: less useful. So typically what you do is you mind
34:51
Speaker 1: uranium and then you try to get the U two
34:53
Speaker 1: thirty five out of it. You can do like centrifuging
34:56
Speaker 1: or any sort of like you know, processing to get
34:58
Speaker 1: it out, and most natural deposits have a pretty small
35:02
Speaker 1: amount of it. It's something like zero points seven per cent.
35:06
Speaker 1: So there was this material that they mined in Gabon
35:08
Speaker 1: and they were processing it in France and they discovered
35:11
Speaker 1: a whole on a second, it's really really low in
35:14
Speaker 1: you two thirty five, And they were wondering, like did
35:16
Speaker 1: somebody steal all the uto thirty five? Like where did
35:19
Speaker 1: all the you two thirty five go? It's like this
35:22
Speaker 1: material has already been depleted of the fission material, because
35:27
Speaker 1: I guess most of the uranium and Earth was sort
35:29
Speaker 1: of created at the same time, and so they all
35:31
Speaker 1: are have the same sort of ratio of the two
35:33
Speaker 1: kinds of uranium. That's right. And it's like a big clock.
35:36
Speaker 1: You know, billions of years ago there was more U
35:38
Speaker 1: two thirty five on Earth, and it's just depleting, like
35:42
Speaker 1: it's just constantly fission ing and breaking up and turning
35:45
Speaker 1: into other stuff. So the U two thirty five fraction
35:49
Speaker 1: in deposits is dropping all over the Earth constantly. And
35:52
Speaker 1: you know where was this made? When did this clock start? Well,
35:56
Speaker 1: we think that this stuff was made like in supernovas
35:58
Speaker 1: or in the collisions of neutron stars billions and billions
36:01
Speaker 1: of years ago, and so it's just been like slowly
36:04
Speaker 1: fission ng into other stuff very gradually over billions of years.
36:09
Speaker 1: And now, just because of where we are in time,
36:12
Speaker 1: it happens to be about points seven percent of natural uranium.
36:16
Speaker 1: So I guess we assume that all of the uranium
36:18
Speaker 1: on Earth was made at the same time, like there
36:21
Speaker 1: was one event that created all this uranium. Yeah, mostly,
36:24
Speaker 1: or at least you know too within a billion years
36:26
Speaker 1: or so. All right, So then we found this piece
36:27
Speaker 1: of uranium rock that had a different ratio of the
36:30
Speaker 1: two kinds of uraniums. It had less of the two
36:33
Speaker 1: thirty five exactly, had less of the useful stuff, the
36:35
Speaker 1: stuff that you could use to do fission. And so
36:38
Speaker 1: for first people were like, hold on a second, somebody
36:40
Speaker 1: must have like slurped it out or stole it or whatever.
36:43
Speaker 1: But then they discovered that all of the deposits from
36:46
Speaker 1: this one mine had this low fraction that you know,
36:49
Speaker 1: that most of the stuff was essentially already depleted of
36:53
Speaker 1: what you could use for fission. And so then they
36:56
Speaker 1: started thinking, hold on a second, maybe this is an
36:58
Speaker 1: example of a natural reactor. Maybe it's just sort of
37:01
Speaker 1: like visioned on its own and burnt out all of
37:04
Speaker 1: the useful uranium, like it's ignited. Right, It's like you're
37:07
Speaker 1: looking for coal deposits, but you find some coal that
37:10
Speaker 1: already looks burned out. Yeah, exactly, And so that's exactly
37:14
Speaker 1: what happened. And what they figured out is that there
37:17
Speaker 1: are very rich deposits of uranium in this mind so
37:20
Speaker 1: like excellent critical mass, just what you need, and that
37:24
Speaker 1: there were cracks in the rock where groundwater could seep in,
37:27
Speaker 1: and so the groundwater would seep in and then surround
37:30
Speaker 1: these deposits and essentially act like a neutron moderator. So
37:35
Speaker 1: like crack and get inside. And you know, this is
37:37
Speaker 1: something that like engineers spent a lot of time becoming
37:40
Speaker 1: proficient in how to design, but it just sort of
37:43
Speaker 1: like happened accidentally and randomly in this one spot, and
37:48
Speaker 1: it was just in the right way to moderate those
37:50
Speaker 1: neutrons so they have the right energy to trigger this
37:53
Speaker 1: self sustaining reaction. So really all you need is like
37:57
Speaker 1: just add water to uranium in the right way and
38:01
Speaker 1: you can get a little nuclear reactor. Yeah, but you
38:03
Speaker 1: need water and like internally, right, you can't just like
38:06
Speaker 1: put a chunk of uranium in a glass of water.
38:09
Speaker 1: You need to be internal so that they can like
38:11
Speaker 1: really capture those neutrons and slow them down and before
38:15
Speaker 1: they hit another piece of uranium. So you need like
38:17
Speaker 1: a cracked piece of uranium, you like a drill holes
38:19
Speaker 1: in uranium first or something. Oh, I see, you need
38:21
Speaker 1: like a little water barrier between different parts of the
38:24
Speaker 1: uranium so that it slows down the neutrons. And then
38:27
Speaker 1: what happens, right, What happens is you produce a lot
38:29
Speaker 1: of heat, and so then the water gets hot and
38:32
Speaker 1: it turns into steam, and it boils away and it
38:34
Speaker 1: turns off the reaction. Then it cools down and more
38:38
Speaker 1: water drips in and it starts again. And so they
38:40
Speaker 1: were able to figure out that this thing was on
38:42
Speaker 1: a three hour cycle. It's like thirty minutes of intense
38:46
Speaker 1: fission reactions boiling this water into steam, and then like
38:49
Speaker 1: a two and a half hours for it to cool
38:51
Speaker 1: down and for water to come back in and for
38:53
Speaker 1: things to kick off again. Wow. And so this happened
38:57
Speaker 1: for how long you think this happened billions of years ago?
39:00
Speaker 1: For a few hundred thousand years. By counting like how
39:04
Speaker 1: much uranium has been depleted, they were able to figure
39:07
Speaker 1: out that this thing went on for quite a long time. Interesting,
39:10
Speaker 1: you said a hundred thousand years this was happening, So
39:12
Speaker 1: for a hundred thousand years, hundreds of thousands, Yeah, So
39:15
Speaker 1: for a few hundred thousand years, it's somewhere in Africa
39:18
Speaker 1: was unseasonably warm, or like the ground, somewhere in the
39:21
Speaker 1: ground or somewhere inside of a mountain, it was sort
39:24
Speaker 1: of like hot. Yeah, it was like a few hundred
39:26
Speaker 1: degrees selfius underground and over several hundred thousand years it
39:31
Speaker 1: consumed the physile material in like several tons of uranium. Wow.
39:37
Speaker 1: So it was like a naturally engineered nuclear reactor exactly.
39:42
Speaker 1: And it's producing crazy radiation right, is shooting off particles.
39:46
Speaker 1: And you know, if it had been really near the surface,
39:48
Speaker 1: it was like caused cancer and any animals or people
39:52
Speaker 1: living nearby. But of course it was billions of years ago.
39:55
Speaker 1: But it happened in Africa. So could that have somehow
39:58
Speaker 1: I don't know, mutative some plad or animal and here
40:02
Speaker 1: we are. Yeah, it's like an ultra version in two
40:03
Speaker 1: thousand one, you know, like a uranium monolith that like
40:06
Speaker 1: mutates our ancestors and makes them intelligent or or dumber.
40:10
Speaker 1: Maybe we would have been smarter if this thing happened. Happened. Interesting,
40:15
Speaker 1: I see, so maybe we are all really superheroes. Origin
40:19
Speaker 1: are and some you know radioactive event. Yeah. The thing
40:22
Speaker 1: I find it really interesting is that it's no longer
40:24
Speaker 1: possible because uranium is naturally depleting itself, Like this depleted
40:29
Speaker 1: itself really rapidly because of this critical mass and the
40:32
Speaker 1: neutron moderators, etcetera. But most uranium just sitting underground is
40:36
Speaker 1: naturally depleting itself, not through as a self sustaining reaction,
40:39
Speaker 1: just as it sort of falls apart and so on. Average,
40:43
Speaker 1: the uranium around the Earth is doesn't have the critical
40:46
Speaker 1: mass anymore to do this. This happened billions of years
40:48
Speaker 1: ago because back then it was much richer in uranium
40:51
Speaker 1: two thirty five. It hadn't like fallen apart yet into
40:54
Speaker 1: the lighter elements. Oh, I see, so this couldn't happen again. Really,
40:58
Speaker 1: even if you like put the water in and just
41:00
Speaker 1: the right way. No, it couldn't happen again. You don't
41:02
Speaker 1: have the critical mass in naturally occurring uranium or anymore anymore,
41:06
Speaker 1: not on Earth that we're aware of. Unless there's like
41:09
Speaker 1: a fresh batch of uranium that just landed from a
41:12
Speaker 1: neutron star collision in a neighborhood or somewhere else on
41:15
Speaker 1: another planet, it could certainly happen. But if there's uranium
41:18
Speaker 1: or the sort of of the same date as the
41:20
Speaker 1: ones that we're typically discovering, then it's no longer rich
41:24
Speaker 1: enough for this to happen. Interesting, I see, it's it's
41:27
Speaker 1: like it's stale exactly. Those camels got stale, to use
41:31
Speaker 1: your analogy, they got a wet or something. And I see,
41:36
Speaker 1: because the kind that we use for like nuclear reactors,
41:38
Speaker 1: the nuclear bonds, we have to like refine it, right,
41:41
Speaker 1: we have to make it richer in this special kind
41:44
Speaker 1: of uranium, hence the famous centrifuges used to make nuclear fuel.
41:47
Speaker 1: All right, so maybe it was once. It sounds like
41:50
Speaker 1: there was only a brief period of time maybe in
41:52
Speaker 1: the history of Earth, where a natural vision reactor could
41:55
Speaker 1: have occurred. But no, no longer, right, that's right. Now
41:59
Speaker 1: it's just up to us humans to engineer the precise
42:02
Speaker 1: conditions necessary to release this energy from the atoms. But
42:05
Speaker 1: I guess it could have happened in other parts of
42:07
Speaker 1: the Earth, not just in Africa, Like there could have
42:09
Speaker 1: been other reactors that we don't know about yet, and
42:12
Speaker 1: there could be reactors happening in other planets, perhaps are
42:15
Speaker 1: in other parts of the galaxy. Sure, this is the
42:17
Speaker 1: only one that we have found, but certainly possible that
42:20
Speaker 1: deeper in the Earth, or just in undiscovered uranium deposits,
42:23
Speaker 1: there's evidence that had happened other times in the history
42:26
Speaker 1: of the Earth, and it's certainly could be happening right
42:28
Speaker 1: now on a fresher planet out there, a less stale camel. Alright, cool, well,
42:33
Speaker 1: I guess the answer to the question, can a fission
42:35
Speaker 1: reactor happened in nature? The answer is yes, With the
42:38
Speaker 1: right conditions and the right time, in the right place,
42:40
Speaker 1: you can have like an actual nature vision reactor. How
42:46
Speaker 1: does that make you feel about the quality of human
42:48
Speaker 1: engineering versus just natural randomness? Well, humans were engineered by nature,
42:53
Speaker 1: so I think nature is the ultimate engineer. About that.
42:57
Speaker 1: Nature should be on all of our papers as well.
43:00
Speaker 1: It should be a Marvel superhero nature nature and should
43:03
Speaker 1: be totally naked right on that tural. Oh man, your
43:07
Speaker 1: mind is going to some interesting places today. Divorced dudity boy, Daniel.
43:13
Speaker 1: You know this is the family friendly podcast, right, We're
43:16
Speaker 1: not trying to fuse it with other ideas. I apologize clearly,
43:19
Speaker 1: the nature character for Marvel should be a camel. You're right,
43:22
Speaker 1: all right, Well, we hope you enjoyed that and then
43:24
Speaker 1: got you to think about what an incredible place nature
43:27
Speaker 1: is right where suddenly, for some reason, fission reactors can happen.
43:32
Speaker 1: That's right, So everything that you can't imagine. It's probably
43:35
Speaker 1: happening out there somewhere in the universe. Events are conspiring
43:39
Speaker 1: to create even the most delicate and elaborate scenarios in
43:43
Speaker 1: which the craziest particle interactions can occur. Well, thanks for
43:47
Speaker 1: joining us, see you next time. Thanks for listening, and
43:57
Speaker 1: remember that Daniel and Jorge Explaining Verse is a production
44:01
Speaker 1: of I heart Radio. For more podcast form My heart Radio,
44:04
Speaker 1: visit the I heart Radio app, Apple Podcasts, or wherever
44:08
Speaker 1: you listen to your favorite shows. Yeah,