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What's in the asteroid belt? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: What if we've been looking for life in all the
0:11
Speaker 1: wrong places. Sure, we're searching for signs of life on Mars,
0:16
Speaker 1: and we're hunting down planets around other stars and far
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Speaker 1: away solar systems, hoping to find one with an atmosphere
0:23
Speaker 1: and maybe even signs of life. But what if life
0:27
Speaker 1: could be out there, but not on a planet, not
0:30
Speaker 1: even on a moon. What if life could be out
0:33
Speaker 1: there but hiding in something much smaller. Hi, I'm Daniel.
0:53
Speaker 1: I'm a particle physicist, a sometimes author, and a twice
0:58
Speaker 1: a week podcast host. You are listening to the podcast
1:01
Speaker 1: Daniel and Jorge Explain the Universe, brought to you by
1:05
Speaker 1: I Heart Radio. My usual co host, Jorge isn't here
1:09
Speaker 1: still this week. He'll be away for a little while,
1:11
Speaker 1: but don't worry, folks, he'll be coming back soon. Our
1:15
Speaker 1: podcast is dedicated to zooming around the universe, exploring everything
1:19
Speaker 1: that's weird, that's amazing, that's crazy, that blows your mind,
1:22
Speaker 1: that maybe you hear scientists talking about but never really
1:26
Speaker 1: understood until today until we break it down for you.
1:30
Speaker 1: So the goal of our podcast is to share with
1:32
Speaker 1: you the amazing, crazy bunkers universe that we live in.
1:36
Speaker 1: Without blowing your mind too much. We want to download
1:40
Speaker 1: that information into your brain so that you really get it,
1:42
Speaker 1: so you can appreciate, just like scientists on the cutting
1:45
Speaker 1: edge of knowledge, how amazing and crazy this universe is.
1:49
Speaker 1: And a lot of times on this podcast we go
1:51
Speaker 1: far away and talk about the center of the galaxy
1:54
Speaker 1: or other galaxies, or the structure of the whole universe,
1:57
Speaker 1: or we zoom down a tiny little particles and talk
1:59
Speaker 1: about how amazing and weird they are and the strange
2:02
Speaker 1: rules that governed life of the quantum realm. But there
2:05
Speaker 1: are mysteries close to home, and we have talked, for example,
2:08
Speaker 1: about the mysteries of lightning and house skip stones, and
2:11
Speaker 1: also about weird things going on in our solar system,
2:14
Speaker 1: and that is the focus of today's episode. We want
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Speaker 1: to understand the weird stuff that's in our neighborhood. We
2:20
Speaker 1: want to make sure, then we look over our shoulder,
2:23
Speaker 1: we understand what's going on, because people think, oh, our
2:26
Speaker 1: solar system, we've been exploring it for hundreds of not
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Speaker 1: thousands of years. Surely we understand what there is to
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Speaker 1: know there. Surely we have a grasp on everything that's
2:34
Speaker 1: going on in the Solar System. Well, not true, and
2:38
Speaker 1: some of those amazing mysteries are hiding in a place
2:40
Speaker 1: you probably don't even think about. If I tell you
2:43
Speaker 1: to imagine the Solar System, you probably think of the Sun.
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Speaker 1: First off, it's the biggest, baddest object in the Solar System,
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Speaker 1: and then of course the planets zooming around it, with
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Speaker 1: the star being our blue globe that we call home.
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Speaker 1: But there's something else there. There's another big piece of
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Speaker 1: the Solar System that takes up a huge chunk. It's
3:01
Speaker 1: an important element, but it's not a dense object like
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Speaker 1: planets in the Sun. It's the asteroid belt. The asteroid
3:09
Speaker 1: belt is this weird collection of rocks between Mars and Jupiter,
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Speaker 1: and it turns out there's a lot of things we
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Speaker 1: don't understand about. It's starting off with why is there
3:18
Speaker 1: an asteroid belt. It goes planet planet, planet, planet, planet,
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Speaker 1: asteroid belt, planet, planet, planet, planet, anything that's weird in science,
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Speaker 1: anything that sticks out, that's a clue that's going to
3:29
Speaker 1: show you the path to an answer. It's gonna reveal
3:32
Speaker 1: something about why it looks that way and not some
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Speaker 1: other way. So every time we find a pattern that
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Speaker 1: doesn't quite fit, we ask why, and hopefully those answers
3:42
Speaker 1: lead to mind blowing discoveries and probably more questions. But
3:46
Speaker 1: it's not just the fact of the asteroid belt that's weird,
3:48
Speaker 1: it's what's inside it. So the question will be answering
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Speaker 1: today is what's going on with the asteroid belt? And
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Speaker 1: I have to share with you that learning about the
4:03
Speaker 1: asteroid belt, I had a personal oh my god, is
4:07
Speaker 1: it aliens moment when one of these strange, bizarre, crazy
4:11
Speaker 1: features of the asteroid belt was first discovered. We'll talk
4:14
Speaker 1: about that soon, but first I was wondering, what do
4:18
Speaker 1: people know about the asteroid belt? Do people out there
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Speaker 1: even know what's in the asteroid belt? And why it's interesting?
4:23
Speaker 1: Does everybody know that there is an asteroid belt? So,
4:26
Speaker 1: as usual to sort of get a sense for how
4:28
Speaker 1: much people know and what their questions are, I walked
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Speaker 1: around campus at you see irvine and I asked people, Hey,
4:35
Speaker 1: what do you think is in the asteroid belt? People
4:38
Speaker 1: thought that was a weird question, but as usual, they
4:40
Speaker 1: were games. So thank you again to the students that
4:42
Speaker 1: use the irvine for answering a weirdos weird questions. Here's
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Speaker 1: what they had to say. But before you answer, think
4:49
Speaker 1: to yourself, do you know what's in the asteroid belt?
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Speaker 1: How accurately could you describe it? Here the answers from
4:55
Speaker 1: students at you see irvine for the most precious rocks,
4:58
Speaker 1: and then now it's a debris because space jump in
5:01
Speaker 1: all that, and then it's accumulating, So it can be
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Speaker 1: I believe, a combination of things of sizes at least
5:08
Speaker 1: from larger to smaller, tiny rocks next to moon, maybe
5:14
Speaker 1: the size of the moon, bigger, I don't know, combination
5:17
Speaker 1: of sand and some other chemicals. I would say they're
5:21
Speaker 1: pretty big rocks, but there's a lot of diversity there.
5:24
Speaker 1: I'm under the impression that it's a lot of rocks
5:26
Speaker 1: and maybe a couple of like icy stuff in there too.
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Speaker 1: They could be as big asn't want to as big
5:33
Speaker 1: as Earth. It just depends, like where you are. I
5:36
Speaker 1: would say it varies a lot, like maybe somewhere from
5:39
Speaker 1: like the car through maybe like a small moon or something.
5:43
Speaker 1: So of course the most popular answer is asteroids. That
5:46
Speaker 1: makes sense. You wouldn't call it the asteroid belt if
5:49
Speaker 1: you didn't have asteroids in it. But what are asteroids?
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Speaker 1: And of course you heard a lot of people say, rocks,
5:55
Speaker 1: big rocks, small rocks, read the little rocks. Some people
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Speaker 1: even thought that there were rocks in there the size
6:00
Speaker 1: of the moon. So there's a big variety of reactions
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Speaker 1: out there to what's in the asteroid belt. So that
6:06
Speaker 1: makes me feel like, yeah, let's dig into it. Let's
6:09
Speaker 1: make sure everybody out there knows what the asteroid belt is,
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Speaker 1: what we know about it, what we don't know about it,
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Speaker 1: and what amazing potential alien discoveries it might be hiding.
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Speaker 1: All right, So first of all, where is the asteroid belt.
6:23
Speaker 1: The asteroid belt is between Mars and Jupiter, right, so
6:27
Speaker 1: we got four inner planets and then we got this
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Speaker 1: big swath or rocks or asteroids, and then we got
6:33
Speaker 1: the outer planets Jupiter, Saturn, and the Neptune Uranus. Of course,
6:38
Speaker 1: so we sort of divides the Solar system. Right, you
6:40
Speaker 1: have these inner rocky planets and then the asteroid belt,
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Speaker 1: and then you've got the big gas planets on the outside.
6:46
Speaker 1: And that seems like a clue, right, So let's dig
6:49
Speaker 1: in a little bit. What is in the asteroid belt. Well,
6:53
Speaker 1: it's not just asteroids, right, Asteroids means a lot of things,
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Speaker 1: and the asteroid belt was discovered actually in the eight hundreds,
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Speaker 1: because some of these asteroids in the belt are big, like,
7:04
Speaker 1: they are really big. In fact, the asteroid belt doesn't
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Speaker 1: just have asteroids in it, it also has dwarf planets,
7:11
Speaker 1: planets that are as big as Pluto, not quite the
7:15
Speaker 1: size of our moon, right, but these are big rocks.
7:18
Speaker 1: And remember, the way we see these things in the
7:20
Speaker 1: sky is we can't see them glow directly. They don't
7:23
Speaker 1: give off light the way the sun does. We can
7:26
Speaker 1: only see them when the Sun's light shines on them
7:28
Speaker 1: and then bounces back to Earth, the same way we
7:31
Speaker 1: see our own moon, which also doesn't actually glow in
7:34
Speaker 1: the sky. It's just a reflection of the light from
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Speaker 1: the Sun. So any of these objects for us to
7:39
Speaker 1: see them, they have to be shiny, and they have
7:42
Speaker 1: to be big, because that's the only way we can
7:44
Speaker 1: see this stuff. So of course, in the eighteen hundreds,
7:47
Speaker 1: the first thing we found were the biggest ones. That's
7:49
Speaker 1: back before we had amazing space telescopes to track all
7:52
Speaker 1: these things down. And there are four objects in the
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Speaker 1: asteroid belt that take up a whopping half of the mass.
8:00
Speaker 1: That's right. You add up all the rocks and set
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Speaker 1: and sand and dust and ice and all that stuff
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Speaker 1: in the asteroid belt, and why it Half of it
8:07
Speaker 1: is in just four objects, and these were the first
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Speaker 1: four scene. Those are Series, which is a little dwarf planet,
8:14
Speaker 1: Vesta Palace, and Hygia. Again, I don't know who's in
8:18
Speaker 1: charge of naming these objects. I'm not even sure how
8:20
Speaker 1: to officially do pronounce them, but I think it's sort
8:23
Speaker 1: of awesome that they're out there, that's sort of dominating
8:25
Speaker 1: the asteroid belt. So it's mostly these big four asteroids.
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Speaker 1: And then in the late eighteen hundreds people were looking
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Speaker 1: more and more and they saw smaller rocks. But it
8:35
Speaker 1: drops off pretty fast, and so it took until about
8:38
Speaker 1: eighteen sixty eight before people had seen a hundred of
8:41
Speaker 1: these things, and then in the early nineteen hundreds they
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Speaker 1: had seen a thousand, and then by one we had
8:48
Speaker 1: found ten thousand individual objects in the asteroid belt. And
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Speaker 1: now we have more than a hundred thousand individual objects characterized.
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Speaker 1: We know where they're going, we know half fast they're spinning,
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Speaker 1: we know their orbit. They each probably have names, though
9:02
Speaker 1: those names, of course are probably not very creative. If
9:05
Speaker 1: you have to name a hundred thousand objects in the
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Speaker 1: Solar System. You probably come up with a scheme, and
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Speaker 1: they probably have really boring names like letters and numbers.
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Speaker 1: So most of the mass is in just four these objects, right,
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Speaker 1: and those are really sort of like many planets. They
9:19
Speaker 1: can't really even call those asteroids. But you know, a
9:22
Speaker 1: lot of this is just terminology. What do you call
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Speaker 1: a planet? What do you call it dwarf planet? What
9:27
Speaker 1: do you call an asteroid? This is just sort of
9:29
Speaker 1: arbitrary stuff that we made up. Like a whole controversy
9:32
Speaker 1: about whether Pluto is a planet or a dwarf planet
9:35
Speaker 1: comes down to semantics. It's not like there's a clear
9:38
Speaker 1: difference between one object and the other. People just have
9:41
Speaker 1: to draw a line somewhere and then you say, well,
9:43
Speaker 1: on this side of the line your planet over here,
9:45
Speaker 1: your dwarf planet. Doesn't really necessarily mean anything. So sometimes
9:49
Speaker 1: I feel like the whole controversy about whether Pluto is
9:52
Speaker 1: a planet or not is a bit overblown. It's there,
9:55
Speaker 1: we know what it is. It's a thing, you know,
9:57
Speaker 1: it's part of our family. Do we have to be
9:59
Speaker 1: so we're about labels anyway? Even if you add up
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Speaker 1: all the stuff in the asteroid belt, all the rocks
10:06
Speaker 1: and dust and ice and all of that stuff that's there.
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Speaker 1: It's only four percent of the mass of the Moon.
10:12
Speaker 1: That's right. The Moon is more than twenty five times
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Speaker 1: more massive than all the stuff in the asteroid belt
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Speaker 1: put together. And that tells you two things. One, we've
10:22
Speaker 1: got a big moon, like it's the truth, like, of
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Speaker 1: all the moons in the Solar System, Earth is odd
10:27
Speaker 1: for having such a big moon. Also, it tells you
10:31
Speaker 1: that the asteroid belt is not that big, right, There's
10:34
Speaker 1: not that much stuff in it. You probably imagine the
10:37
Speaker 1: asteroid belt is like space totally dotted with rocks, and
10:41
Speaker 1: like that scene in Star Wars where the Millennium Falcon
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Speaker 1: is trying to navigate its way at high speed through
10:46
Speaker 1: those rocks and just barely whizzing by and almost crashing.
10:49
Speaker 1: That's not the experience we have when we send probes
10:53
Speaker 1: through the asteroid belt, because the asteroid belt is not
10:56
Speaker 1: that dense. Remember, space is big, like really really big.
11:01
Speaker 1: If you're gonna fly out into the Solar System, you're
11:03
Speaker 1: very unlikely to hit a planet, right, because even though
11:06
Speaker 1: planets are big, they're not big compared to the Solar System.
11:10
Speaker 1: In the same way, the asteroid belt. Even though it's
11:13
Speaker 1: distributed across lots of little rocks, it still doesn't fill
11:17
Speaker 1: up space. It doesn't even come close to filling up space.
11:20
Speaker 1: We have sent lots of probes to the outer part
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Speaker 1: of the Solar System and never even worried about having
11:25
Speaker 1: them hit an asteroid. It's difficult, in fact, to hit
11:28
Speaker 1: an asteroid. The Japanese recently sent up an awesome probe
11:32
Speaker 1: to land on an asteroid and punch it to see
11:34
Speaker 1: what it's made out of and understand, you know, is
11:37
Speaker 1: it made out of carbon or silicon or ice or whatever.
11:39
Speaker 1: And that was hard, right, So it's not easy to
11:42
Speaker 1: run into an asteroid. If you want to fly your
11:44
Speaker 1: spaceship through the asteroid belt, most likely you'll never even
11:47
Speaker 1: see one. And if you just watch these things, they
11:50
Speaker 1: don't even bounce into each other. Very often. Asteroids of
11:53
Speaker 1: any size hit each other around every ten million years.
11:56
Speaker 1: And that's because number one, there aren't very many in
11:59
Speaker 1: space big, but also number two, because it's been around
12:02
Speaker 1: for billions of years, and so by now a lot
12:05
Speaker 1: of those collisions that were if they were going to happen,
12:08
Speaker 1: they sort of already happened. And what you have left
12:10
Speaker 1: is a bunch of asteroids in their own lane. It's
12:13
Speaker 1: like a huge traffic jam, but all the collisions have
12:16
Speaker 1: happened already, and all those wrecks have been towed off
12:19
Speaker 1: the road, and now you just have a bunch of
12:21
Speaker 1: clean lanes and safe drivers and everybody's sort of go
12:24
Speaker 1: in their own way, so you can very safely navigate
12:27
Speaker 1: through the asteroid belt, though you'll see some weird stuff,
12:30
Speaker 1: like some of these rocks that we see in the
12:32
Speaker 1: asteroid belt are kind of hard to understand. Some of
12:35
Speaker 1: them are spinning super fast, Like it takes the Earth
12:38
Speaker 1: twenty four hours to rotate one time, but it takes
12:41
Speaker 1: these rocks less than thirty seconds some of them to
12:44
Speaker 1: rotate to do a full rotation, and one of them,
12:47
Speaker 1: the speed champion the asteroid belt, doesn't complete turn in
12:51
Speaker 1: ten seconds, so it's spinning like crazy. And while most
12:55
Speaker 1: of the things in the Solar System go in the
12:56
Speaker 1: same direction, and that comes from the initial angular momentum
13:00
Speaker 1: in the Solar system that's rotating blob of gas and
13:03
Speaker 1: dust that formed the star and the planets and all
13:06
Speaker 1: that stuff, some of them are going the opposite direction
13:09
Speaker 1: their retrograde. They're like spinning the wrong way. So there's
13:13
Speaker 1: a lot of clues there, and there's a lot of
13:14
Speaker 1: clues about how the Solar System was formed. Why is
13:17
Speaker 1: the asteroid belt there? Why is it there and looked
13:19
Speaker 1: like this, Why does it have these weird elements in
13:21
Speaker 1: it doing this strange stuff? A lot of fascinating questions
13:25
Speaker 1: to dig into, and we'll dig into them, but first
13:27
Speaker 1: we'll take a quick break. All right, So we're talking
13:42
Speaker 1: about the asteroid belt. What mysteries does it contain? What
13:46
Speaker 1: secrets of the origin of the Solar System are hidden
13:49
Speaker 1: there in the asteroid belt? Well, it turns out a lot.
13:52
Speaker 1: And the first question you might ask, if you're a
13:54
Speaker 1: scientist is why isn't there a planet there? Like why
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Speaker 1: is there an asteroid belt and not just a planet?
14:01
Speaker 1: If you make a plot of the distance from the
14:03
Speaker 1: Sun of the various planets and you start with the ones,
14:06
Speaker 1: you know, then there's sort of a gap there. You
14:09
Speaker 1: expect there to be a planet there between Mars and Jupiter.
14:13
Speaker 1: And very early astronomers, they were big into these kind
14:16
Speaker 1: of patterns. We didn't have a detailed mathematical understanding of
14:19
Speaker 1: how things worked, even before gravity and understanding orbits and stuff.
14:23
Speaker 1: People were just looking at patterns like the distances from
14:26
Speaker 1: these planets to the Sun, and it just didn't look right.
14:30
Speaker 1: There was this weird gap there and made people think
14:32
Speaker 1: could there be another planet there hiding. Then of course
14:35
Speaker 1: we saw the little rocks there, and people understood, oh,
14:38
Speaker 1: there's no planet there. There's just sort of a big
14:41
Speaker 1: slew of rocks. But it makes you wonder why. And
14:44
Speaker 1: one of the most natural stories to imagine is maybe
14:47
Speaker 1: there used to be a planet there. Maybe there was
14:50
Speaker 1: an ancient planet and got ripped apart by some disaster,
14:53
Speaker 1: and what we're looking at now is basically the shrapnel
14:56
Speaker 1: from some ancient murder mystery. They even named it. It's
14:59
Speaker 1: called Phaeton, which is a really cool name for a planet. Unfortunately,
15:03
Speaker 1: that's a cool story, but it's unlikely to be the
15:06
Speaker 1: accurate scientific description of what happened there. But it just
15:09
Speaker 1: shows you that people have been thinking about this for
15:11
Speaker 1: a long time. People have been wondering why is an
15:14
Speaker 1: asteroid belt there, Why isn't there a planet. And to
15:17
Speaker 1: understand why there isn't the planet there, why we have
15:19
Speaker 1: an asteroid belt, we have to understand two things. First
15:23
Speaker 1: is how the Solar System was formed, Like, where did
15:25
Speaker 1: this all come from? Anyway? How are any of the
15:28
Speaker 1: planets made? And why wasn't there one made there? Well,
15:31
Speaker 1: we think that the Solar System, it's ancient progenitor, is
15:34
Speaker 1: just a big cloud of gas and dust and stuff.
15:38
Speaker 1: Some of that gas is hydrogen, which probably comes from
15:41
Speaker 1: the Big Bang. It's left over from billions of years ago.
15:44
Speaker 1: Some of it is helium, also maybe from the Big
15:46
Speaker 1: Bang or fused together hydrogen in the COREUS stars. And
15:50
Speaker 1: then the rest of it, the heavier elements, either made
15:53
Speaker 1: in old stars which then blew up and spewed their
15:56
Speaker 1: remains all over the university, gathered back together by gravity,
16:00
Speaker 1: or even the remnants of neutron star collisions. Remember, all
16:03
Speaker 1: the gold and the heavy elements on Earth were made
16:06
Speaker 1: not in stars, not in supernovas, but instead they were
16:10
Speaker 1: made when neutron stars collided. Because that's the crazy situation.
16:15
Speaker 1: You need to fuse those heavy metals. And we have
16:17
Speaker 1: a whole podcast episode about that, which I suggest people
16:20
Speaker 1: dig into if they like these questions. So we have
16:23
Speaker 1: the raw materials, we've got the hydrogen, we've got the helium,
16:25
Speaker 1: we got the heavy stuff. All this is left over
16:28
Speaker 1: from previous activity in the universe and then what happens. Well, gravity,
16:32
Speaker 1: Gravity is the dominant force that controls the structure of
16:36
Speaker 1: the universe. It's the weakest force. It's totally weird. We
16:39
Speaker 1: don't understand is it a force, is it just a
16:42
Speaker 1: bending of space? Is it something else? Can it be
16:44
Speaker 1: described by quantum mechanics. We have so many questions about gravity,
16:48
Speaker 1: But one thing we do know about it is that
16:50
Speaker 1: it almost always wins in the end because it's patient.
16:54
Speaker 1: And remember that gravity has this other feature that, unlike
16:57
Speaker 1: the other forces, it can't be opposed, like electromagnetism can
17:01
Speaker 1: be balanced. You can have things that are neutral, but
17:04
Speaker 1: gravity operates on everything with mass, and because we've never
17:07
Speaker 1: seen anything with negative mass, gravity is only attractive. And
17:11
Speaker 1: so it just keeps pulling and pulling and pulling. It's patient,
17:15
Speaker 1: it's slow, but eventually it does what it needs to do.
17:19
Speaker 1: And so you take this huge cloud of gas and
17:22
Speaker 1: dust spread out across an enormous area, and slowly the
17:26
Speaker 1: gravitational forces between these particles, tiny little objects. It tugs
17:30
Speaker 1: them closer and closer, and it gathers them together and
17:33
Speaker 1: eventually gathers it together. So densely that you get things
17:36
Speaker 1: like stars and planets and other stuff. And you might think, first, well,
17:42
Speaker 1: why doesn't it just gather everything together into one big blob, right,
17:46
Speaker 1: Why doesn't it just make a big star? Why do
17:48
Speaker 1: you get anything but the star? Then initial cloud of
17:51
Speaker 1: gas and dust and particles. It's spinning, of course, because
17:54
Speaker 1: everything in the universe is spinning from some previous interaction
17:58
Speaker 1: that happened, maybe from the initial looks illusion of the
18:00
Speaker 1: supernova or whatever that generated that stuff. And that spinning
18:04
Speaker 1: can't just go away. Remember, in our universe we have momentum,
18:07
Speaker 1: so if you push something in space, it will go forever.
18:10
Speaker 1: If you start something spinning, it'll spin forever until something
18:14
Speaker 1: stops it. And so this cloud of gas and dust
18:17
Speaker 1: that created our solar system was spinning, and it is
18:19
Speaker 1: still spinning, and that spinning keeps it from collapsing, but
18:23
Speaker 1: only in the direction that it's spinning. It's spinning around
18:27
Speaker 1: a plane. That plane is now the plane of our
18:29
Speaker 1: solar system, and that's why everything in our solar system
18:32
Speaker 1: is sort of flat, is spinning around the same axis
18:35
Speaker 1: because that's the original access of spin. And in that direction,
18:39
Speaker 1: gravity can't do everything. It's opposed by this rotation. The
18:43
Speaker 1: rotation keeps it from falling into the very center. That's
18:46
Speaker 1: why the Earth is in orbit around the Sun rather
18:48
Speaker 1: than just falling in. That's why the Moon is in
18:51
Speaker 1: orbit around the Earth rather than just falling in. But
18:54
Speaker 1: in the other direction, perpendicular to the plane of the
18:57
Speaker 1: Solar System, there's no rotation, and so gravity can do
19:01
Speaker 1: its job and it flattens things as much as it can.
19:04
Speaker 1: So gravity does all this work, and some of the
19:07
Speaker 1: stuff is spread out, some of the gas and the
19:09
Speaker 1: dust doesn't fall all the way into the center because
19:12
Speaker 1: of this rotation. So the stuff in the center condenses
19:15
Speaker 1: into a star, and the rest of the stuff grabs
19:17
Speaker 1: itself together. It forms into these distributed objects, and that's
19:20
Speaker 1: how you get the planets. The planets are only there
19:23
Speaker 1: because the original blob was rotating. If it wasn't rotating,
19:26
Speaker 1: we would just have one star. But now you have
19:28
Speaker 1: these large gravitational objects, these planets, and they start to
19:32
Speaker 1: affect the stuff around them. And Jupiter, of course, is
19:35
Speaker 1: the monster planet. It has most of the mass of
19:38
Speaker 1: all the planets. It's tiny compared to the Sun, but
19:41
Speaker 1: of course it's huge compared to the Earth. And it
19:44
Speaker 1: has its own gravity, and that gravity is very powerful,
19:47
Speaker 1: and it yanks and it pulls on things. We've talked
19:50
Speaker 1: to in this podcast about how Jupiter massages its own
19:53
Speaker 1: moons because of the tidal forces, and this is exactly
19:56
Speaker 1: the issue. We think that the gravity from Jupiter is
19:59
Speaker 1: too strong to let the stuff in the asteroid belt
20:03
Speaker 1: ever pull together to form a planet. So the asteroid
20:06
Speaker 1: belt is sort of like leftovers from the original formation
20:09
Speaker 1: of the Solar System. We think that a long time ago,
20:12
Speaker 1: maybe in the first ten million years of the Solar System,
20:15
Speaker 1: most of the Solar System looked a lot like the
20:17
Speaker 1: asteroid belt ahead rocks and chunks of stuff that were
20:20
Speaker 1: slowly gathering together. But Jupiter prevents those rocks in the
20:23
Speaker 1: asteroid belt from getting any further. It keeps them down
20:27
Speaker 1: from creating their own planet. It's like Jupiter is like
20:29
Speaker 1: a union buster, right. It says, nobody get together. I'm
20:32
Speaker 1: gonna treat you all individually. And so the tidal forces
20:36
Speaker 1: from Jupiter prevent this from happening. Every time Jupiter sweeps around,
20:39
Speaker 1: it tugs on all these objects and prevents them from
20:42
Speaker 1: gathering together. Remember, gravity is slow, and gravity is gentle
20:46
Speaker 1: and it doesn't take that much perturbation to prevent it
20:49
Speaker 1: from pulling all of this stuff together. And Jupiter is
20:51
Speaker 1: a big, popa planet, and when it sweeps around it
20:54
Speaker 1: messes it all up. And you might think, well, if
20:57
Speaker 1: Jupiter can do that on the inside, wasn't to do
20:59
Speaker 1: that on the out side. Well, the reason is that
21:01
Speaker 1: Saturn is further away from Jupiter. There's a bit more
21:03
Speaker 1: space there, and literally there's more space there, not just
21:06
Speaker 1: in the gap between the objects, but because Saturn is
21:10
Speaker 1: further out, it has much more space to move, and
21:13
Speaker 1: Jupiter's gravity drops from much more rapidly as you got
21:16
Speaker 1: on the outside compared to being on the inside. While
21:19
Speaker 1: it seems more dramatic to have had a planet there
21:21
Speaker 1: which then got torn up in some sort of ancient
21:23
Speaker 1: battle or collision between objects, that's not the case. In fact,
21:27
Speaker 1: nothing really even got started there. They think there used
21:29
Speaker 1: to be a lot more asteroids than the asteroid belt
21:32
Speaker 1: when the Solar System was young, but then those got
21:34
Speaker 1: tugged out of orbit and collided and probably a lot
21:37
Speaker 1: of those hit the Earth. There's this period in the
21:39
Speaker 1: early Solar System called the late heavy bombardment when a
21:42
Speaker 1: lot of objects came raining in and landing on the
21:45
Speaker 1: Earth and the other inner planets. So most of the
21:47
Speaker 1: asteroid belt from the very early days has been lost,
21:50
Speaker 1: either due to collisions like we talked about earlier, hitting
21:53
Speaker 1: other planets, or just getting tugged out of their orbit
21:56
Speaker 1: by Jupiter. So what we have is a small remnant
21:59
Speaker 1: of our original asteroid belt. We're lucky, frankly, they even
22:02
Speaker 1: have it at all. But there are some really fascinating
22:05
Speaker 1: objects in the asteroid belt, and one in particular, that
22:08
Speaker 1: dwarf planet Series that holds a special mystery, one that's
22:11
Speaker 1: been in my mind for years, and we'll talk all
22:14
Speaker 1: about it, but first let's take another break, al right.
22:29
Speaker 1: So we're talking about the mysteries of the asteroid belt,
22:32
Speaker 1: why we have it where it is, what's in the
22:34
Speaker 1: asteroid belt, And the big Papa asteroid in the asteroid
22:37
Speaker 1: belt is actually a planet, and it's called Series C
22:40
Speaker 1: E R E S. And it's pretty big. It's almost
22:44
Speaker 1: a thousand kilometers in diameter. This is no small rock.
22:47
Speaker 1: This is something to be taken seriously. And Series is
22:50
Speaker 1: a fascinating object for many reasons. But the thing that
22:53
Speaker 1: really sticks out of me is something which literally sticks out.
22:57
Speaker 1: They sent a probe past and it took a picture
22:59
Speaker 1: of Series, and he saw something really weird on the surface.
23:02
Speaker 1: All right, if you haven't heard of this before, it's
23:04
Speaker 1: gonna blow your mind. It blew my mind when I
23:07
Speaker 1: heard it. Series has something on it which looks like
23:10
Speaker 1: a pyramid. Now, I know, pyramids are a favorite element
23:14
Speaker 1: of stories of the occult, and people think maybe aliens
23:17
Speaker 1: came to Earth and built pyramids and all sorts of stuff,
23:20
Speaker 1: and a lot of that, of course, is nonsense. But
23:22
Speaker 1: there is a weird pyramid on Series. And when I
23:25
Speaker 1: first saw these pictures, I gasped. I thought, oh my gosh,
23:30
Speaker 1: maybe this is the moment we find an alien artifact.
23:34
Speaker 1: And I read a lot of science fiction and I'm
23:36
Speaker 1: desperate defined aliens, and in a lot of those science
23:39
Speaker 1: fiction stories where humanity comes across aliens, this is how
23:43
Speaker 1: it starts. We find some weird feature on somewhere in
23:46
Speaker 1: the Solar System and can't be explained. I mean, think
23:48
Speaker 1: about two thousand and one, right, the monolith it was
23:51
Speaker 1: there orbiting Jupiter. What we're looking for is something unnatural,
23:55
Speaker 1: something strange, something which we cannot explain without invoking intelligent life.
24:00
Speaker 1: And something like a pyramid. Wow, that's amazing. Now, this
24:04
Speaker 1: pyramid on Series is pretty weird. First of all, it
24:08
Speaker 1: rises five thousand meters above the surface. That's not tiny.
24:13
Speaker 1: That's enormous, especially compared to the size of Series. It's
24:18
Speaker 1: fully one percent of the height of Series itself. If
24:22
Speaker 1: you had an object, if you had a feature that
24:24
Speaker 1: big on Earth, it would be eight times higher than
24:27
Speaker 1: Mount Everest right in relative size to the Earth. So
24:31
Speaker 1: this is not a tiny mountain. If you are on Series,
24:33
Speaker 1: you would definitely know about it. It seems like it's
24:36
Speaker 1: about two hundred million years old. And they can date
24:39
Speaker 1: these things by seeing how many collisions there are nearby stuff.
24:43
Speaker 1: You can tell how old something is on in the
24:45
Speaker 1: Solar System just by counting the sort of collision to
24:48
Speaker 1: impact craters, because everything in the Solar System eventually is
24:51
Speaker 1: hit with little rocks. Now, NASA, when they first saw it,
24:53
Speaker 1: they announced this and they describe this, and I'm gonna
24:55
Speaker 1: quote here they say, it's quote like nothing humanity has
24:59
Speaker 1: ever scene. And not only is it something we've never
25:02
Speaker 1: seen before, there's not even any other one on Series.
25:06
Speaker 1: It's not like we saw this planet and we're like, oh, look,
25:09
Speaker 1: it has all these weird bumps on it. How could
25:12
Speaker 1: that be? What makes those It's maybe evidence of some
25:15
Speaker 1: new geological feature. There's only one. So we have this
25:19
Speaker 1: weird planet in the asteroid belt with this strange pyramid
25:22
Speaker 1: on it. And this is not just a mountain which
25:25
Speaker 1: looks a little bit like a pyramid. The first pictures
25:28
Speaker 1: it looked a lot like a pyramid. It looked like
25:30
Speaker 1: an artificial structure. This is the kind of thing that
25:33
Speaker 1: makes people go, wow, we better get another picture of
25:36
Speaker 1: this thing. And so of course they did. They sent
25:38
Speaker 1: out more probes and they focus telescopes on it, and
25:40
Speaker 1: everybody wanted to know what is this weird thing on Series?
25:44
Speaker 1: And the short answer is we still don't really know.
25:47
Speaker 1: There are some nice ideas. People think that Series underneath
25:52
Speaker 1: has a molten core, but it's not molten rock. The
25:55
Speaker 1: inside of the earth. When you dig down into the earth,
25:57
Speaker 1: this molten rock. Because of all the pressure, Series has
26:01
Speaker 1: molten mud. Right. Do you think that there's water on Series?
26:05
Speaker 1: Maybe liquid water and it combines with a service to
26:07
Speaker 1: make this sort of molten mud, and that sometimes this
26:11
Speaker 1: mud might push up or spew up based on something
26:14
Speaker 1: happening on the inside of series, and this mud is
26:18
Speaker 1: actually not that hot, and so they call this sort
26:20
Speaker 1: of like a cryo volcano, like a cold volcano. So
26:24
Speaker 1: they think it's like some salty, rocky, frozen mud that
26:28
Speaker 1: came out from the interior and pushed up like a
26:30
Speaker 1: big ZiT. And that's possible, and they have some simulations
26:34
Speaker 1: that suggests this kind of thing could happen. But then
26:37
Speaker 1: why is there only one? Why is there just this
26:40
Speaker 1: one feature? If this is the kind of thing that
26:42
Speaker 1: happens inside series, you would expect to see more than one,
26:46
Speaker 1: and you'd expect to see big ones and then lots
26:48
Speaker 1: of little ones. But you know, sometimes weird things happen.
26:52
Speaker 1: Sometimes in the solar system, there's a one off event,
26:56
Speaker 1: and that could explain it. It could just be a strange,
26:59
Speaker 1: one off event in the solar system that nobody understands.
27:02
Speaker 1: Or hey, it could be aliens. We're still not are now.
27:07
Speaker 1: Don't go running off and tell people that Daniel said
27:09
Speaker 1: they're aliens in the Solar system. There probably aren't. That
27:13
Speaker 1: kind of explanation requires extraordinary evidence. But I really enjoy
27:17
Speaker 1: thinking about it. I really enjoy holding out hope that
27:20
Speaker 1: maybe one of these things we're seeing in the Solar
27:22
Speaker 1: system is not just going to tell us about the
27:24
Speaker 1: origins of our solar system and how it was formed
27:26
Speaker 1: and how planets are formed, and how solar systems everywhere
27:30
Speaker 1: put together, and those are all fascinating questions I want
27:32
Speaker 1: the answer to. But I'm holding out hope that maybe
27:35
Speaker 1: there's a clue in our Solar system of something weirder,
27:37
Speaker 1: something grander, something which reveals the secret about the universe
27:41
Speaker 1: we have been dying to know the answer to, namely,
27:44
Speaker 1: are we alone? And so it turns out that the
27:47
Speaker 1: asteroid belt not only does it have lots of these
27:49
Speaker 1: fun mysteries in it, but there's lots of places to hide.
27:52
Speaker 1: There's lots of these asteroids we haven't examined, and there's
27:55
Speaker 1: still the possibility that we could land on one of
27:58
Speaker 1: these and explore it and find some thing weird, something
28:01
Speaker 1: weirder even than a pyramid. We could find alien technology,
28:04
Speaker 1: We could find all sorts of crazy stuff. The point
28:06
Speaker 1: is that there's a huge amount of area in our
28:09
Speaker 1: Solar system that remains unexplored, lots of opportunities to find life,
28:13
Speaker 1: to find alien civilization, to find all sorts of crazy
28:17
Speaker 1: stuff that would literally blow our minds. And so while
28:20
Speaker 1: we should zoom our minds around the universe and think
28:22
Speaker 1: about all the crazy stuff happening far away and also
28:25
Speaker 1: under our feet, remember that right here in our neighborhood
28:28
Speaker 1: there are plenty of opportunities to make mind blowing, earth shattering,
28:33
Speaker 1: paradigm shifting discoveries. All right, this has been an episode
28:37
Speaker 1: of Daniel and Jorge Explain the Universe, all about the
28:40
Speaker 1: mysteries of the Asteroid Belt. Thanks for tuning in, and
28:43
Speaker 1: if you have questions about something you'd like to hear
28:45
Speaker 1: us talk about, please send them to us at Questions
28:48
Speaker 1: at Daniel and Jorge dot com. Thanks for tuning in.
28:59
Speaker 1: If you still have a question after listening to all
29:02
Speaker 1: these explanations, please drop us a line. We'd love to
29:05
Speaker 1: hear from you. You can find us at Facebook, Twitter,
29:07
Speaker 1: and Instagram at Daniel and Jorge That's one word, or
29:11
Speaker 1: email us at Feedback at Daniel and Jorge dot com.
29:15
Speaker 1: Thanks for listening, and remember that Daniel and Jorge Explain
29:18
Speaker 1: the Universe is a production of I Heart Radio. For
29:21
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