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Are there centaurs in outer space? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Daniel, do you think the universe is still capable
0:11
Speaker 1: of surprising us? What do you mean? It's blowing my
0:14
Speaker 1: mind all the time, that is what I mean. You're
0:17
Speaker 1: always saying that we could discover anything out there. I
0:19
Speaker 1: do say that, like, you know, there might be huge
0:22
Speaker 1: purple dragons out there past the edge of the observable universe. Yeah,
0:26
Speaker 1: but then what if we actually discover huge purple dragons?
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Speaker 1: Would you be like I saw that coming? No, I
0:33
Speaker 1: would think like, wow, so cool. I wonder how we
0:36
Speaker 1: could talk to dragons about business. But you don't think
0:39
Speaker 1: there are actually dragons in space? Do you? Probably not?
0:42
Speaker 1: But hey, some future astronomer listening today, we'll discover a
0:46
Speaker 1: new kind of fiery star out there and call it
0:49
Speaker 1: a space dragon. I guess you could say it be
0:52
Speaker 1: in the night sky, you know, at night with the
0:54
Speaker 1: k Sir Jorge, that is a terrible joke. Hi am
1:12
Speaker 1: Orham made cartoonists and the creator of PhD Comics. Hi.
1:15
Speaker 1: I'm Daniel, I'm a particle of physicist, and I really
1:18
Speaker 1: do want to meet a space dragon. Welcome to our podcast,
1:21
Speaker 1: Daniel and Jorge Explain the Universe, a production of I
1:24
Speaker 1: Heart Radio in which We talk about all the things
1:26
Speaker 1: that are out there in the universe, the things that
1:29
Speaker 1: amaze us, the things that blow our minds, the things
1:31
Speaker 1: that make us curious, and also the things that we
1:34
Speaker 1: wonder if they are out there, the crazy hypothetical, the possible,
1:39
Speaker 1: the things that will blow the minds of future generations.
1:42
Speaker 1: And explain all of them to you. Is this Daniel
1:44
Speaker 1: where science fiction meets fantasy is who has been a
1:49
Speaker 1: tight connection between science and science fiction, and that connection
1:53
Speaker 1: is the fantasy of science fiction authors thinking of crazy
1:57
Speaker 1: stuff we might see one day. I mean, like agents
2:00
Speaker 1: and space dragons. Yeah, exactly. And I think that there's
2:03
Speaker 1: a lot of folks out there who are scientists or
2:06
Speaker 1: read science fiction who also appreciate fantasy and crazy dragons
2:10
Speaker 1: and magic and wizards and all that. Do you think
2:13
Speaker 1: there's some science spaces for any of that. No, I
2:16
Speaker 1: think it's all based in mythology. But it's all creative
2:19
Speaker 1: and I like reading it. So we usually talk about
2:21
Speaker 1: science fiction on this program, but I'm also a big
2:23
Speaker 1: reader of fantasy novels. But yeah, we talk about all
2:26
Speaker 1: the amazing things out there in the universe, all of
2:28
Speaker 1: the weird and unexplained objects and there's a lot of
2:32
Speaker 1: stuff out there in the universe and in space, floating
2:35
Speaker 1: out there. Who knows what's out there. Yes, And the
2:37
Speaker 1: more we look out there in space, the more we
2:39
Speaker 1: discover that there are lots of different kinds of things
2:43
Speaker 1: we never even imagined, and also that the distinctions between
2:47
Speaker 1: the categories we thought were crisp and clear are a
2:50
Speaker 1: little fuzzier than we understood. Yeah, there's a pretty big
2:53
Speaker 1: diversity out there, because it's not just suns and planets
2:56
Speaker 1: out in space floating out there and the darkness of
2:59
Speaker 1: the cosmos. But there's other kinds of objects, and sometimes
3:02
Speaker 1: they're kind of hard to categorize. That's right. The Solar
3:05
Speaker 1: System is more than just a sun and a few
3:07
Speaker 1: planets and a couple of moons. There's a huge spectrum
3:11
Speaker 1: of stuff all the way down from space dust up
3:14
Speaker 1: to the Sun itself and basically everything in between. And
3:18
Speaker 1: where we draw the lines. What we call a planet,
3:20
Speaker 1: what we call a brown dwarf, what we call a star,
3:23
Speaker 1: what we call an asteroid, sometimes just has like a
3:26
Speaker 1: historical basis more than a scientific one. So if there
3:29
Speaker 1: are dwarf planets, Daniel or they're also elf planets, those
3:34
Speaker 1: have been taken over by the dwarfs. That's all that's left.
3:36
Speaker 1: The dwarves won that war, they leave for the West already.
3:39
Speaker 1: That's right. There's a whole other set of solar systems,
3:42
Speaker 1: deep deep in the galaxy where the elves have retreated to.
3:45
Speaker 1: But I mean, this is sort of a continuing conversation
3:48
Speaker 1: I feel with astronomers, like what counts as a planet,
3:51
Speaker 1: as an asteroid, as a space rock, or even as
3:54
Speaker 1: a sun. So it's hard to tell the difference between
3:57
Speaker 1: a sun and a planet. Yeah, exactly, if Jupiter was bigger,
4:00
Speaker 1: it would be right on that threshold where you might
4:02
Speaker 1: argue like it's a really big planet, No it's a
4:05
Speaker 1: failed star. No, it's a brown dwarf. And this isn't
4:08
Speaker 1: just like astronomers being picky or astronomers coming up with
4:12
Speaker 1: silly names for things. This just reflects how we look
4:15
Speaker 1: out at the sky and see different kind of things
4:17
Speaker 1: and try to make sense of them. You can't just say, hey,
4:19
Speaker 1: there's lots of stuff out there. We can't categorize it
4:21
Speaker 1: at all. You have to try to say, we're talking
4:24
Speaker 1: about these kinds of stuff and that kind of stuff.
4:26
Speaker 1: And when you face a bunch of messy observations. You
4:29
Speaker 1: have to try to find categories and patterns. Yeah, So
4:32
Speaker 1: today we'll be talking about one such object in the
4:34
Speaker 1: Solar System, one that has a pretty mythic name to
4:38
Speaker 1: be on the program. We'll be talking about what is
4:45
Speaker 1: a space centaur and what happens when they do battle
4:49
Speaker 1: with space dragons or space unicorns. That's that's the one
4:52
Speaker 1: I want to right around in. Well, that is an
4:55
Speaker 1: ancient rivalry unicorns versus centaurs. They do not get along really.
4:59
Speaker 1: Oh man, can you have a space centaur with a horn?
5:05
Speaker 1: Where would the horn go? Exactly? Based uni center? Would
5:08
Speaker 1: it go on the forehead of the guy or the woman?
5:12
Speaker 1: Where else would it go? I don't know. I mean
5:15
Speaker 1: I guess it could come out of their chest? Yeah, exactly.
5:18
Speaker 1: Like I have a lots of basic quests about centers,
5:20
Speaker 1: like where is their belly button? You know, is it
5:22
Speaker 1: sort of on the person part or all the way
5:24
Speaker 1: down or like you know, anyway, a lot of interesting
5:28
Speaker 1: questions you could talk about when it comes to centaurs. Well,
5:31
Speaker 1: but that's a different podcast. That would be the Dungeons
5:34
Speaker 1: and Space Dragons podcast. Daniel and Jorge explained the universe
5:38
Speaker 1: of fantasy creatures. But yeah, there's is such a thing
5:41
Speaker 1: as a space center, like this is actually something that
5:45
Speaker 1: physicists talk about in conferences and in papers. That's right. Yeah,
5:48
Speaker 1: it's something pretty awesome. And it came up on the
5:51
Speaker 1: podcast a few weeks ago, just sort of obliquely when
5:53
Speaker 1: we were talking about other things in the Solar System,
5:56
Speaker 1: and we got a bunch of listeners right in saying,
5:58
Speaker 1: what is that real? Are there actually space centaurs? And
6:01
Speaker 1: so we thought we would dive into it into a
6:03
Speaker 1: whole episode. They thought you were kidding or so they're
6:07
Speaker 1: calling us out. They're calling us out, and we are
6:10
Speaker 1: stepping up and explaining exactly what a space center actually think.
6:14
Speaker 1: You didn't just make all this stuff up twenty minutes
6:17
Speaker 1: before we started. No, this is not a fiction podcast.
6:20
Speaker 1: This is real. But you know, sometimes in science we
6:23
Speaker 1: borrow words from other fields, We borrow them from art
6:26
Speaker 1: or from philosophy to try to describe some relationship we see,
6:29
Speaker 1: to try to capture something about this new kind of
6:32
Speaker 1: object that we can't describe in any other way. And
6:35
Speaker 1: sometimes it seems creative and clever, and sometimes it seems
6:38
Speaker 1: awkward and clunky. What percentage, Daniel, what percentage of physics
6:41
Speaker 1: names you think are awkward versus right on? Well, I
6:45
Speaker 1: would estimate that you would place it about clunky, But
6:50
Speaker 1: I think there's some art to them, you know. I
6:52
Speaker 1: think sometimes I see where they're going, even if they
6:54
Speaker 1: didn't necessarily really hit the target. All right, Well, as usual,
6:58
Speaker 1: we were wondering how many people out there had heard
7:01
Speaker 1: of a space center or even knew what it could
7:04
Speaker 1: possibly be. So Daniel went out there into the wild
7:07
Speaker 1: to the internet to ask people what is a space centaur?
7:11
Speaker 1: And thank you to everybody who volunteered to answer this
7:14
Speaker 1: particularly strange question. If you are willing to put your baseless,
7:18
Speaker 1: unresearched answers to difficult physics questions on the podcast, please
7:22
Speaker 1: write to me at questions at Daniel and Jorge dot com.
7:26
Speaker 1: You'll think about it for a second. Is someone approached
7:28
Speaker 1: you and asked you what a space centaur is, what
7:33
Speaker 1: would you say. Here's what listeners had to say. I
7:36
Speaker 1: do not know what a space centauris, but I know
7:40
Speaker 1: what a center is, so I'm guessing it's an astrological
7:45
Speaker 1: phenomena that feels like magic, but it's actually a science.
7:49
Speaker 1: I have no idea what that is. Uh, but it
7:52
Speaker 1: sounds like a new kind of tesla, or maybe a
7:54
Speaker 1: rocket of some kind. The space center is a NASA operate,
7:58
Speaker 1: a museum where villites I engage with space science. If
8:02
Speaker 1: it isn't a mythical beast that flies through the cosmos,
8:04
Speaker 1: then I imagine it's a classification of some kind. I
8:09
Speaker 1: have a memory of it being something to do with
8:11
Speaker 1: maybe an unstable orbit or some kind of like collision
8:14
Speaker 1: course in the future. I think I heard about these
8:17
Speaker 1: things a few weeks ago Discovery. So I see a
8:23
Speaker 1: rocky objects between Jupiter and Neptune. A space center sounds
8:32
Speaker 1: like a constellation, maybe near Alpha cent Tori. If not that,
8:36
Speaker 1: then some kind of nebula. Maybe A space center is
8:41
Speaker 1: a child about human from Earth and a human born
8:43
Speaker 1: in another planet, say Mars, for example. So I don't
8:46
Speaker 1: know about you, but I feel like we got exceptionally
8:48
Speaker 1: creative answers this week. A tesla, I think my favorite
8:54
Speaker 1: is the child of a human from Earth and a
8:56
Speaker 1: human born on another planet. What a great idea to
8:59
Speaker 1: call that a space center. That is pretty good. It's
9:01
Speaker 1: like the writing science fiction fantasy right now exactly. I
9:05
Speaker 1: hope that sparked somebody to write their whole novel. Nobody
9:08
Speaker 1: thought it was an actual center, and everyone sort of
9:10
Speaker 1: assumed it's some kind of object in space. Yeah, but
9:13
Speaker 1: it's such a weird thing that nobody heard of that
9:15
Speaker 1: the guesses were pretty wide. I mean, one person was
9:18
Speaker 1: guessing that it was a space center because I think
9:20
Speaker 1: the idea of a centaur was so strange. They must
9:23
Speaker 1: have thought I made a typo in the question a
9:26
Speaker 1: space center does make more sense than a space center?
9:30
Speaker 1: All right, well, let's jump into it, Daniel. I assume
9:33
Speaker 1: the answer is going to be very magical and legendary,
9:36
Speaker 1: but step us through it. What is a space center?
9:39
Speaker 1: So to understand what a centaur is, you first have
9:42
Speaker 1: to understand two other things, and that's asteroids and comets,
9:47
Speaker 1: because that's what you're saying. Before you know, you look
9:49
Speaker 1: out into space and you see lots of really weird
9:51
Speaker 1: stuff out there, and the deeper you look, the more
9:54
Speaker 1: weird stuff you see. And the more we learned that
9:56
Speaker 1: there's a lot of objects out there in space. It's
9:59
Speaker 1: not just planets and the Sun and a few moons.
10:02
Speaker 1: There are zillions of asteroids, and there's lots of comets,
10:05
Speaker 1: and then out there beyond Pluto, there's an enormous number
10:08
Speaker 1: of frozen rocks. So astronomers are trying to come to
10:11
Speaker 1: grift with this incredible number and variety of stuff by
10:15
Speaker 1: giving them all names that describe roughly what they do.
10:18
Speaker 1: Some of these names are like anchored in history because
10:21
Speaker 1: they come from very early observations. Right, Astronomy is a
10:24
Speaker 1: field that's hundreds or thousands of years old, So to
10:28
Speaker 1: understand what a centaur is, you really need to understand
10:30
Speaker 1: first what an asteroid is, and what a comet is.
10:33
Speaker 1: According to what modern astronomers said, is that another mythical rivalry,
10:38
Speaker 1: like unicorns, there's a centaurs asteroids versus commets. No asteroids
10:42
Speaker 1: and comets get along. In fact, sometimes they mix and
10:45
Speaker 1: form space centaurs or space mermaids. Oh my goodness, that's
10:50
Speaker 1: the next level mermaids. Yeah, exactly. That would have been
10:53
Speaker 1: even a better name, because makes sense for things to
10:55
Speaker 1: swim through space rather than gallop through space with their
11:00
Speaker 1: with an unknown bellyable location. Yeah, that's right. Maybe they
11:03
Speaker 1: can swim through the sea of dark matter that's out
11:05
Speaker 1: there using their dark matter tails and lure astronauts to
11:10
Speaker 1: their doom. Alright, so it sounds like we need to
11:14
Speaker 1: understand what asteroids and comets are, and I'm guessing many centaurs.
11:17
Speaker 1: It's like a mix of the two or somewhere in between. Yeah, exactly.
11:21
Speaker 1: So an asteroid is a really cool object. It's basically
11:23
Speaker 1: just a big rock floating out in space that didn't
11:26
Speaker 1: get gathered together into a moon or a planet. But
11:29
Speaker 1: it has a really interesting history. The word asteroid basically
11:33
Speaker 1: means not a star because it's something that early astronomers
11:37
Speaker 1: saw out there in space. But it was too small
11:40
Speaker 1: to look like a planet, right, You couldn't like see
11:42
Speaker 1: a disk, but it moved the way a planet did.
11:45
Speaker 1: It wasn't so far away, it didn't move like a star.
11:48
Speaker 1: So it's this weird object that was discovered when they said, well,
11:51
Speaker 1: it must be nearby because it moves like a planet,
11:54
Speaker 1: but it's really really small and it looks like a star.
11:57
Speaker 1: So they gave you this new name. Oh interesting. I
12:00
Speaker 1: guess I hadn't thought about it that we would have
12:03
Speaker 1: discovered asteroids before we had powerful telescopes, right, I guess
12:07
Speaker 1: at the beginning, it was just like a strangely moving
12:11
Speaker 1: pinpoint of light in the nights cut exactly. An Asteroids,
12:14
Speaker 1: like planets, don't shine light right there, just big dark rocks,
12:17
Speaker 1: but they can't reflect light, and so light goes from
12:20
Speaker 1: the Sun and bounces off it and comes to Earth.
12:22
Speaker 1: Then we can see them, and that's good because we'd
12:24
Speaker 1: like to know where the asteroids are so that we
12:26
Speaker 1: know they're not going to smash into the Earth. And
12:28
Speaker 1: we identified a few of them very very early on.
12:31
Speaker 1: It was like in the eighteen hundreds we had already
12:33
Speaker 1: seen ten of them. These are the bigger ones, the
12:35
Speaker 1: shinier ones, and so we could see that they were
12:38
Speaker 1: out there and they were floating around the Solar System.
12:41
Speaker 1: And for a long time, people like didn't even distinguish
12:43
Speaker 1: between a planet and an asteroid. In science papers from
12:47
Speaker 1: the eighteen hundreds, those two words are used interchangeably. It
12:51
Speaker 1: just means like a floating object in space that reflects light. Yeah,
12:54
Speaker 1: it's not a star. It's closer by, it's like orbiting
12:57
Speaker 1: our Sun and it's reflecting light. And from that point
13:00
Speaker 1: of view, what's the difference between Mars and a really
13:03
Speaker 1: big asteroid. They're both just big rocks in space, right.
13:07
Speaker 1: But then as you learn about these objects, you start
13:10
Speaker 1: to distinguish them. He's like, well, planets move in their
13:12
Speaker 1: own orbit and basically have cleared a path, whereas most
13:15
Speaker 1: asteroids are in a big belt. And so you come
13:17
Speaker 1: up with these ways of talking about things because they're related,
13:21
Speaker 1: but they're also important differences between planets and asteroids. It's
13:24
Speaker 1: not just a difference of size, like I would think
13:26
Speaker 1: it would be like a size threshold that you have
13:28
Speaker 1: to meet to be a planet. Isn't that what happened
13:30
Speaker 1: to Pluto, Like it wasn't big enough, so they got downgraded. Yeah,
13:34
Speaker 1: that is sort of what happened to Pluto. But it's
13:36
Speaker 1: also context, Like Pluto we found and it's out there
13:38
Speaker 1: and it's moving sort of like a planet. But then
13:41
Speaker 1: we found that Pluto is actually just one example of
13:43
Speaker 1: a lot of different objects that are deep out there
13:46
Speaker 1: in the Solar System, and it's not even necessarily the biggest,
13:49
Speaker 1: and so calling it a planet would mean you have
13:50
Speaker 1: to call all those other ones a planet also. So
13:53
Speaker 1: then yeah, they made an arbitrary distinction. They're like, sorry,
13:56
Speaker 1: we're going to define a planet to be just bigger
13:58
Speaker 1: than Pluto. The sort of get Pluto out the door?
14:01
Speaker 1: Is that why? Because they didn't want to admit there
14:04
Speaker 1: were a lot of planets in the Solar System. Yeah, well,
14:07
Speaker 1: they didn't feel comfortable with the idea of having lots
14:09
Speaker 1: and lots of planets in an unknown number of planets,
14:11
Speaker 1: because out there past Pluto, there's an enormous number of
14:15
Speaker 1: these things. These things are called trans Neptunian objects, and
14:19
Speaker 1: some of them are called plutoids or plutinos. But there's
14:22
Speaker 1: a huge number of these things out there, and if
14:24
Speaker 1: you said Pluto is a planet, then you'd have to
14:26
Speaker 1: call them all planets. And you know, planets have a
14:29
Speaker 1: historically important name, you know, like we like to think
14:32
Speaker 1: it's a special class of objects in the Solar System
14:34
Speaker 1: that we call planets because we live on one. So yeah,
14:37
Speaker 1: we could have gone with like there are many many planets,
14:40
Speaker 1: but they wanted to make it special. They wanted to
14:42
Speaker 1: reserve the name for special occasions. That was kind of
14:46
Speaker 1: I guess it was like, you know, you have friends,
14:48
Speaker 1: and you have best friends, and you could say, well,
14:50
Speaker 1: all my friends are my best friends, or you could
14:53
Speaker 1: acknowledge that some of your friends are actually closer than
14:55
Speaker 1: other friends. Right, I do have a friend who calls
14:58
Speaker 1: all of our friends best friends, and it's so confusing.
15:03
Speaker 1: Something there you go exactly, So then what was the
15:06
Speaker 1: rationale or what was the official excuse that they go
15:08
Speaker 1: by size. The long saga of the definition of Pluto,
15:11
Speaker 1: I think deserves its own episode. Um, we can go
15:14
Speaker 1: through the details of that. But we were saying that
15:16
Speaker 1: asteroids were discovered, you know, in the eighteen hundreds, we
15:18
Speaker 1: have at ten of them, and then it rapidly cranked up.
15:21
Speaker 1: We had like discovered a thousand asteroids by the early
15:24
Speaker 1: nineteen hundreds, and by now we know that there are many,
15:27
Speaker 1: many of these things that are like probably more than
15:30
Speaker 1: a million asteroids, and a lot of them are floating
15:33
Speaker 1: in this asteroid belt, which is this big chunk of
15:36
Speaker 1: space between Mars and Jupiter, and some of them are
15:39
Speaker 1: actually co orbiting with Jupiter, like Jupiter has its orbit
15:43
Speaker 1: right this big circle, and in other places in that
15:46
Speaker 1: same orbit where Jupiter isn't there are big blobs of asteroids,
15:50
Speaker 1: big clumps of asteroids floating in the same path. They
15:53
Speaker 1: can share the same orbit. Wouldn't they have a different
15:56
Speaker 1: speed or something. They can share the same orbit, and
15:58
Speaker 1: they have a cool name. They're called Upiter Trojans. Yes,
16:02
Speaker 1: they really are called Jupiter trojans, and they get into
16:06
Speaker 1: these weird gravitational resonances with Jupiter because Jupiter is having
16:10
Speaker 1: a big influence on all the stuff that's going on
16:12
Speaker 1: in the Solar System out there, So you can't just
16:14
Speaker 1: ignore Jupiter. Jupiter is a huge gravitational attraction. Remember that
16:19
Speaker 1: of the stuff in the Solar System is the Sun,
16:22
Speaker 1: and of that remaining one percent, Jupiter is most of
16:24
Speaker 1: it jupiters of that one percent, So the first approximation
16:29
Speaker 1: the Solar System is just the Sun and Jupiter. So
16:31
Speaker 1: if you're out there near Jupiter has a huge influence
16:34
Speaker 1: on what's happening gravitationally, and some of these rocks get
16:37
Speaker 1: tossed down into the inner Solar System by Jupiter, they
16:40
Speaker 1: get disturbed, and some of them found these resonances where
16:43
Speaker 1: they can stay happily in Jupiter's orbit. All right, Well
16:47
Speaker 1: that's an asteroid, and so that's one half of the
16:50
Speaker 1: space center puzzle. The other have our comments, which we'll
16:54
Speaker 1: get into in a short bit, But first let's take
16:57
Speaker 1: a quick break. All right, Danny, we're talking about space mermaids. Unicorns.
17:13
Speaker 1: Man unicorns stand space unicorns. I guess maybe more like
17:17
Speaker 1: space Vegas is too. That could be pretty cool. They're like,
17:20
Speaker 1: have birds have courses? Right? Yeah? Or what about griffins?
17:23
Speaker 1: Are those like half birds half lions? Right? Those would
17:26
Speaker 1: be cool space griffins, space hippogriffs. That that's the next level.
17:32
Speaker 1: Most of these things we just made up. But some
17:34
Speaker 1: of these things are real and are out there in space.
17:36
Speaker 1: But they're also just sort of funny names that astronomers
17:39
Speaker 1: gives to things to try to show us the relationships
17:41
Speaker 1: between what they've discovered. All right, So an asteroid is
17:44
Speaker 1: a space rock. That's sort of the definition somewhere between
17:48
Speaker 1: like a baseball and what like the size of the
17:51
Speaker 1: Moon is what would be considered an asteroid. Yeah, they're
17:54
Speaker 1: like between a meter and up to like five dred kilometers.
17:57
Speaker 1: The biggest one called Vesta is like five hundred kilometers wide,
18:01
Speaker 1: and they're mostly rocks, and they're mostly in the Inner
18:04
Speaker 1: Solar System so they don't have a lot of ice,
18:06
Speaker 1: so they can be pretty big and they're mostly rock
18:09
Speaker 1: and they are in the Inner Solar System. Those are
18:11
Speaker 1: the key points to be an asteroid. Really, what if
18:13
Speaker 1: you're a big rock but you're outside of the Inner
18:16
Speaker 1: Solar System, but bomb you might be a centaur. I see,
18:21
Speaker 1: it's like a location. It's like a discriminating by where
18:24
Speaker 1: you're from, all right, So that's one half of the puzzle.
18:27
Speaker 1: The other half of our comets. Now, comets are different
18:30
Speaker 1: than asteroids. Comets are different from asteroids. They come from
18:33
Speaker 1: a different place in the Solar System. They come from
18:36
Speaker 1: out beyond Neptune, the Kuiper Belt. This is huge collection
18:41
Speaker 1: of rocky and icy objects. So that's the second key.
18:45
Speaker 1: Comets come from deeper out either the Kuiper Belt or
18:48
Speaker 1: the Orc Cloud, and they are made of different stuff.
18:51
Speaker 1: They tend to have a lot more ice in them.
18:53
Speaker 1: They're these big, dirty snowballs of ice and dust. And
18:56
Speaker 1: there's a reason for that. There's more ice out in
18:58
Speaker 1: the far edges of the Solar System because it was
19:01
Speaker 1: colder out there. The water in the inner Solar System
19:03
Speaker 1: got sort of blown out by the pressure from the
19:06
Speaker 1: Sun out to the outer Solar System. So rocks that
19:08
Speaker 1: coalesce out there deeper in space tend to have more
19:12
Speaker 1: ice in them. So comets come from the Kuiper Belt
19:15
Speaker 1: or the Arch Cloud, which is this hypothetical collection of
19:18
Speaker 1: trillions of icy objects deep out there, and they tend
19:23
Speaker 1: to be made more of ice, like water ice or
19:25
Speaker 1: like messane ice, both kinds of ice or other kinds
19:28
Speaker 1: of liquids, all kinds of ice. And don't get me
19:30
Speaker 1: started on how planetarry geologists talk about ice like they
19:33
Speaker 1: talk about the ice giants of Neptune, and they say
19:36
Speaker 1: these things are filled with water ice, but they don't
19:38
Speaker 1: actually mean these things are frozen water to them, like
19:41
Speaker 1: a water ice. It's a whole category of states of
19:44
Speaker 1: water that could be solid but could also be technically
19:47
Speaker 1: a liquid, but are not actually frozen water. So the
19:51
Speaker 1: whole idea of an ice is a very sort of
19:52
Speaker 1: confusing in general topic which is badly named. But in general,
19:57
Speaker 1: there is a lot of frozen water and a lot
19:59
Speaker 1: of very areous organic ices out there in the deep
20:02
Speaker 1: Solar system. All right, we won't get you started that, Daniel.
20:06
Speaker 1: Although ice giants also sounds like a mythological creature, Well,
20:10
Speaker 1: Neptune is reel and it's out there, and it's called
20:12
Speaker 1: an ice giant even if it has a lot of
20:14
Speaker 1: water and no ice. But these comets, they're also tend
20:18
Speaker 1: to be smaller, like you know, they're not up to
20:21
Speaker 1: five kilometers wide. They're like five to five miles wide,
20:26
Speaker 1: and you can tell that they're made of different stuff
20:27
Speaker 1: because when they plummet to the inner solar system, they
20:30
Speaker 1: get a coma and they get a tail, like their
20:33
Speaker 1: edges tend to be burned off by the sun the
20:35
Speaker 1: solar pressure, it's frying the outside, and you get this
20:39
Speaker 1: long tail of material. It's basically coming off of the comet.
20:42
Speaker 1: So they're not like as densely packed that they tend
20:45
Speaker 1: to be more susceptible to the Sun. I guess further
20:48
Speaker 1: out there, away from the Sun, it's more likely for
20:52
Speaker 1: molecules to form into solids because it's colder, and so
20:55
Speaker 1: there's just more things you can make rocks out of,
20:58
Speaker 1: whereas maybe closer to the Sun, you know, there are
21:00
Speaker 1: certain things like water or methane that evaporate. That's right.
21:03
Speaker 1: Your distance to the Sun definitely changes the composition of
21:07
Speaker 1: materials in the solar system, which are the basic building
21:09
Speaker 1: blocks of everything we're talking about. And it's really fascinating.
21:13
Speaker 1: And you know, we've only until recently seen one example
21:16
Speaker 1: of a solar system ours, and now we're starting to
21:19
Speaker 1: see other solar systems and we're looking at those and
21:21
Speaker 1: we're saying Hey, are the patterns that are in our
21:24
Speaker 1: Solar system also present in those? And we're finding really
21:27
Speaker 1: surprising things, like we're finding huge planets like the size
21:30
Speaker 1: of Jupiter really really close to the Sun, not just
21:33
Speaker 1: in the outer Solar system. These are called hot Jupiters.
21:36
Speaker 1: We actually did a whole fun podcast episode about this
21:39
Speaker 1: is our Solar System weird and all the things we're
21:41
Speaker 1: learning about our Solar system by looking at others. But
21:44
Speaker 1: in general what you say is corrected. That tend to
21:47
Speaker 1: be different kinds of things deeper in the Solar System
21:49
Speaker 1: than closer in, and this affects how these objects come together.
21:53
Speaker 1: And it's one reason why comets are different from asteroids
21:56
Speaker 1: because they're made of different stuff because they come from
21:58
Speaker 1: further app interesting, can we see asteroids and comets and
22:02
Speaker 1: other solar systems yet? And b wouldn't it be cool
22:06
Speaker 1: to have a novel about bix space war between our
22:09
Speaker 1: centaurs and there are unicorns and another solar systems mermaids
22:14
Speaker 1: that would I want to read a book called Exo
22:16
Speaker 1: Mermaids would be pretty cool mermaids. No, we think we
22:23
Speaker 1: have seen a comment from another solar system, but we
22:25
Speaker 1: can't see them in their solar system. We think that
22:28
Speaker 1: oh muamua, that weird cigar shaped object that came through
22:31
Speaker 1: our solar system a couple of years ago wasn't exo mermaid.
22:34
Speaker 1: It was probably a lost comment from another solar system,
22:38
Speaker 1: but we don't know. It came through really fast, and
22:40
Speaker 1: we only spotted it when it was halfway through the
22:42
Speaker 1: solar system, so we only got like good pictures as
22:45
Speaker 1: it was on its way out. So there's still a
22:47
Speaker 1: lot of questions about what exactly OMMA was. But most
22:51
Speaker 1: likely it was something from another solar system's equivalent of
22:54
Speaker 1: the Orc cloud that got lost and ejected into space
22:57
Speaker 1: and drifted over here. But we can't see these things
23:00
Speaker 1: from other solar systems because they're so small. Like if
23:03
Speaker 1: we wanted to point your telescope at another star, we
23:06
Speaker 1: can just barely detect the planets, which are these huge masses.
23:10
Speaker 1: So we're very far from being able to see exo
23:12
Speaker 1: asteroids or exo commets or exo mermaids. All right, So
23:15
Speaker 1: those are commets, And now the comets have sized restrictions too,
23:19
Speaker 1: or do they also range from like small to gigantic.
23:22
Speaker 1: They tend to be smaller than asteroids and that's because
23:25
Speaker 1: they form deeper out and they just haven't gathered together
23:27
Speaker 1: into larger objects, and Neptune tends to keep these things small.
23:31
Speaker 1: Like Neptune is also a really big planet, and so
23:34
Speaker 1: it's gravity tends to break stuff up because of tidal forces,
23:38
Speaker 1: and so anything in the Kuiper Belt that would gather
23:40
Speaker 1: together into a larger object generally gets torn apart by Neptune.
23:44
Speaker 1: It's like the big bully on the playground out there
23:46
Speaker 1: and doesn't want anything to challenge its supremacy. So they
23:49
Speaker 1: tend to be up to about like twenty five miles wide.
23:52
Speaker 1: Do we think, wow, So there's an active effort not
23:55
Speaker 1: to have more planets. That's right. It's a good old
23:58
Speaker 1: boys club, you know, and it's old worth something. If
24:00
Speaker 1: it's exclusive, you can keep people out. That tunes the bouncer,
24:06
Speaker 1: it's the enforcer exactly, all right. So that those are
24:09
Speaker 1: asteroids in comments, And now I'm guessing that a space
24:13
Speaker 1: center is like a mix of the two. Is it
24:15
Speaker 1: like half asteroid half commet Like the top half is one,
24:19
Speaker 1: the bottom half is another. Where do you put the
24:21
Speaker 1: horn on the space center exactly? Or the belly button right?
24:24
Speaker 1: And the asteroids half belly buttons due depends on how
24:28
Speaker 1: they are born. Deep mystery of science, they have multiple
24:31
Speaker 1: belly bons. Well, you're sort of right. A space center
24:36
Speaker 1: is half asteroid half comet, but not in the sense
24:39
Speaker 1: that a centaur is. It's not like you take an asteroid,
24:41
Speaker 1: cut it in half and slap it onto the half
24:44
Speaker 1: of a comet and this weird hybrid object you would
24:46
Speaker 1: call a centaur. That would be pretty cool, but like
24:48
Speaker 1: the tail trailing, that would be like a pretty killer commet. There. Yeah,
24:53
Speaker 1: it's sort of like punk, you know, like shave half
24:54
Speaker 1: your head and have the other half long or something,
24:57
Speaker 1: or maybe it's like a mullet. This is in the
24:59
Speaker 1: front rocking the front party in the back. Anyway, a
25:03
Speaker 1: centaur is not an actual mix of an asteroid and
25:06
Speaker 1: a comet. It's an object which has some of the
25:09
Speaker 1: characteristics of both, so it doesn't fall neatly into either category.
25:15
Speaker 1: And this is what I was saying earlier, is that
25:16
Speaker 1: as we look deeper into the Solar system and catalog
25:19
Speaker 1: more and more stuff, we find that the transitions between
25:22
Speaker 1: our categories are kind of fluid and fuzzy and in
25:25
Speaker 1: the end kind of arbitrary, you know. We have to
25:27
Speaker 1: make categorizations so we can talk about stuff. You know,
25:30
Speaker 1: when you go to a meeting of astronomers and you say,
25:32
Speaker 1: I'm studying the planets, you don't want to every time
25:35
Speaker 1: have to define what you mean by a planet, so
25:37
Speaker 1: that you've got to have words we can all agree on,
25:40
Speaker 1: even if they are arbitrary. So what we've discovered is
25:42
Speaker 1: that there is a population of rocks out there which
25:46
Speaker 1: don't fall nicely into either the category of asteroid or
25:50
Speaker 1: of comet. So the solution was give it a cool name,
25:54
Speaker 1: and now everyone's happy, and now everyone's happy. But now
25:58
Speaker 1: everyone said arguing about whether or not account as a
26:00
Speaker 1: space center or not. Yeah, exactly. And so these things
26:04
Speaker 1: are fun because they're sort of like comets because we
26:07
Speaker 1: think they come from deeper in the Solar System than asteroids.
26:11
Speaker 1: They're on these sort of longer elliptical orbits. Their orbits
26:14
Speaker 1: go out to like between Jupiter and Neptune. All the
26:17
Speaker 1: asteroids are in the inner Solar System, but the space
26:20
Speaker 1: centers they go out all the way to Neptune sometimes,
26:24
Speaker 1: so there's sort of like comets because they also they
26:26
Speaker 1: have some of these commas, like you can see these
26:29
Speaker 1: sort of fuzz around them that's getting blown off by
26:33
Speaker 1: the Sun. So they seem sort of like comets because
26:35
Speaker 1: they come from deeper in the Solar System and they
26:37
Speaker 1: have this fuzz. But they're also like asteroids because they're
26:42
Speaker 1: really really big. Some of them are way too big
26:45
Speaker 1: to be considered comets. And they also they cross the
26:48
Speaker 1: paths of these giant planets like comets and unlike asteroids.
26:53
Speaker 1: So there really are sort of a mix of the
26:55
Speaker 1: characteristics of the two different things. So wait, these are
26:59
Speaker 1: objects that they have like a tail, like comments like
27:01
Speaker 1: they have you know, like a trail of stuff facing
27:04
Speaker 1: away from the sun of like melted water or liquid.
27:08
Speaker 1: They don't have a tail to have a coma. What's
27:11
Speaker 1: the difference. So a tail usually comes if you have
27:13
Speaker 1: like stuff that can be vaporized, like water or other
27:16
Speaker 1: things which can be vaporized, and dusk coma is more
27:19
Speaker 1: like you know, the little bits of stuff on it
27:22
Speaker 1: are sort of floating around it. These things are big
27:25
Speaker 1: enough that they can have their own gravity, so they
27:27
Speaker 1: can sort of hold onto these things. In fact, one
27:30
Speaker 1: of them is so big is has its own ring system,
27:33
Speaker 1: like you know Saturn has rings. What there's this one centaur.
27:37
Speaker 1: It's called charik Low and it's three hundred kilometers wide.
27:41
Speaker 1: It's the biggest known centaur and it orbits between Saturn
27:45
Speaker 1: and Urineus and it has rings around it. That's how
27:47
Speaker 1: big it is. It has its own gravity. Wow, what
27:50
Speaker 1: do you call the moon of a centaur? Daniel, I'm
27:54
Speaker 1: gonna have to defer to the official astronomy naming department,
27:57
Speaker 1: Like a fairy, a space ferry, I think, so us,
28:00
Speaker 1: a nymph maybe ego? Right, So it's it's like it
28:04
Speaker 1: has an entourage. It's not just the rock. It's like
28:06
Speaker 1: a rock with some fuzz, yeah, And that tells you
28:09
Speaker 1: a little bit about what it's made out of. That
28:11
Speaker 1: there's a big component of sort of space dust in there,
28:14
Speaker 1: not just like big deposits of metal and rock like
28:17
Speaker 1: an asteroid, more like space dust like a comet. And
28:21
Speaker 1: so that makes it more like a comet and less
28:23
Speaker 1: like an asteroid. But it doesn't have ice, or does it?
28:26
Speaker 1: Some of them? Maybe? I see these things are much
28:29
Speaker 1: more rare than the other ones, and so they're not
28:31
Speaker 1: as well studied. There's only like two hundred and fifty
28:34
Speaker 1: of them that have actually been identified. But you know,
28:37
Speaker 1: we can only really see the bigger ones. So the
28:39
Speaker 1: estimates range from like forty thousand of these things too,
28:42
Speaker 1: there might be ten million of these things out there
28:44
Speaker 1: in the Solar System. Okay, so then it's like an asteroid,
28:47
Speaker 1: you said, because of its size, but also it's orbit. Yeah,
28:52
Speaker 1: it's it's like an asteroid because it's really really big,
28:55
Speaker 1: and it's sort of unlike an asteroid because of its orbit.
28:58
Speaker 1: Like asteroids tend to stay either in the asteroid belt
29:01
Speaker 1: or in Jupiter's orbit. These Jupiter trojans that we talked
29:04
Speaker 1: about before, these guys tend to be more stable than
29:08
Speaker 1: a comet, right, But they have these orbits that are
29:10
Speaker 1: really long and elliptical, and they pass the giant planets.
29:14
Speaker 1: They're like cross over the orbits of the giant planets.
29:17
Speaker 1: Sometimes they're further out than Jupiter. Sometimes they're closer in
29:20
Speaker 1: than Jupiter. So that sort of makes them more like
29:23
Speaker 1: a comet. But then again they're sort of big, lack
29:25
Speaker 1: an asteroid. Interesting. I don't know, I'm not getting a
29:28
Speaker 1: big comet vibe from these, you know what I mean,
29:31
Speaker 1: Like it feels like maybe just like a rogue asteroid
29:33
Speaker 1: or something. All right, Well, you know, on the common
29:35
Speaker 1: side of it. They have these big elliptical orbits and
29:38
Speaker 1: we think that maybe they came from the Kuiper Belt,
29:41
Speaker 1: Like these things don't look like the same kind of
29:44
Speaker 1: material that makes up asteroids. They're made it more of
29:47
Speaker 1: the same stuff that comments are made out. So I
29:50
Speaker 1: guess this is the kind of argument that astronomers would
29:52
Speaker 1: have a conferences. They're like, oh, but it's big, so
29:55
Speaker 1: it must be an asteroid. No, it has this weird orbit,
29:57
Speaker 1: so it must be a comment. So that's why they
29:59
Speaker 1: came up with the name. Yeah, yeah, exactly. And of
30:02
Speaker 1: course nobody even agrees on what the definition of a
30:05
Speaker 1: space center is. There's like seven different definitions of a
30:09
Speaker 1: space center for real, for real, Like JPL has one,
30:15
Speaker 1: the Jet Propulsion Lab in Pasadena down here in southern California.
30:19
Speaker 1: They define a space center in one way. And then
30:22
Speaker 1: there's another group called the Minor Planet Center, which is
30:25
Speaker 1: an important institution in astronomy, and they have a different
30:28
Speaker 1: definition for what a space center is. And the differences
30:31
Speaker 1: in like how you measure the orbit details doesn't matter
30:35
Speaker 1: if you cross Neptune or if you cross Jupiter, and
30:37
Speaker 1: these are just like totally arbitrary, but conflicting definitions of
30:41
Speaker 1: what a space centaur is. I guess there's such a
30:44
Speaker 1: weird variety of stuff out there that, you know, you
30:47
Speaker 1: kind of need more names to be able to talk
30:49
Speaker 1: about all these things. And it gets tricky when you
30:52
Speaker 1: try to put things into bins. Or you could just
30:54
Speaker 1: be inclusive and say, hey, there's just sort of stuff
30:56
Speaker 1: out there, and they're all my best friends, and they're
30:59
Speaker 1: all a little bit different, and you can categorize them by,
31:02
Speaker 1: you know, their orbit and their composition and not get
31:04
Speaker 1: so hung up on names. I guess space stuff, planet stars,
31:10
Speaker 1: everything in between is just space stuff. It's all just
31:12
Speaker 1: particles to me, right, Like this is a big collection
31:15
Speaker 1: of particles, a little collection of particles. What's the difference
31:19
Speaker 1: two particle physicists. I guess all five percent of the
31:22
Speaker 1: universe looks like a particle. All right, let's get into
31:24
Speaker 1: where they actually come from and if we have actually
31:29
Speaker 1: set ined some with our very own eyes. But first
31:32
Speaker 1: let's take another quick break. All right, Daniel, we're talking
31:46
Speaker 1: about space centaurs, which are a mix of asteroids and
31:50
Speaker 1: comets that are like you know, space giant space rocks
31:53
Speaker 1: that are kind of in between. They're big and rocky,
31:57
Speaker 1: but they also have these weird orbits that make them
32:01
Speaker 1: sort of like commets. Yeah, and so there's sort of
32:03
Speaker 1: a mix between the two different things. And some things
32:07
Speaker 1: are called comets, some things are called asteroids, some things
32:10
Speaker 1: are called centaurs, and then you have these weird objects
32:12
Speaker 1: that nobody agrees about because they fall sort of like
32:15
Speaker 1: in between the definitions from different organizations. So there's an object,
32:20
Speaker 1: for example, called Chiron, which some folks classify as a comet,
32:24
Speaker 1: some folks classify as an asteroid, and some folks classify
32:27
Speaker 1: as a space centaur. So it's a little bit of everything. Wow. Yeah,
32:30
Speaker 1: I guess there's no agreed upon a set of definitions,
32:34
Speaker 1: Like there's no International Space Stuff Naming Committee. No. I
32:39
Speaker 1: think the problem is there are too many of those
32:41
Speaker 1: committees and they don't agree with each other. And so
32:44
Speaker 1: I think this like controversy about Pluto and is it
32:47
Speaker 1: a planet or is it a dwarf planet or whatever,
32:50
Speaker 1: it's just the tip of the iceberg. It's just the
32:52
Speaker 1: tip of the frozen comet. When it comes to like
32:54
Speaker 1: the naming controversies we're gonna be facing in the future
32:57
Speaker 1: as we discover more and more stuff out are in
33:00
Speaker 1: the Solar System, and people are gonna be arguing like
33:02
Speaker 1: should you name stuff based on where it is now
33:05
Speaker 1: or where you think it was formed, or what it's
33:07
Speaker 1: made out of, or it's possible history or its gravitational
33:11
Speaker 1: role in the Solar System. And there's lots of like
33:14
Speaker 1: philosophical differences about how you categorize this stuff that I
33:17
Speaker 1: think we're gonna be hearing more and more about in
33:19
Speaker 1: the future. I guess maybe some naming groups are like
33:23
Speaker 1: you know, committees, some of them are groups, some of
33:25
Speaker 1: them are centers, so they're just sort of a naming
33:28
Speaker 1: war for those two. That's true, Yeah, exactly, the naming
33:32
Speaker 1: centaur wars. All right, well, step of three, or where
33:35
Speaker 1: can we see one and what what do they look like?
33:37
Speaker 1: So we've never actually photographed one up close, like we've
33:40
Speaker 1: identified them in telescopes. We see these things, we can
33:44
Speaker 1: tell that they're they're they're reflected light, but we've never
33:47
Speaker 1: liked passed a space probe by one to get a
33:50
Speaker 1: close up picture of the way we have of asteroids
33:52
Speaker 1: and of comets, and of course of planets and dwarf
33:55
Speaker 1: planets and all those other kinds of things. So space
33:58
Speaker 1: centers or one of those last things that are really
34:00
Speaker 1: unexplored in our Solar system. And there's some really fascinating
34:04
Speaker 1: questions about what they are and where they come from.
34:07
Speaker 1: Like question number one is why do they have their
34:10
Speaker 1: weird colors? Like they have colors. There's different colored space centaurs. Yeah,
34:14
Speaker 1: there are two different kinds of space centaurs at least,
34:18
Speaker 1: and they range from very very red sort of like
34:21
Speaker 1: the surface of Mars too much more blue sort of
34:24
Speaker 1: like Urinus. And so that's fascinating that there's these two camps.
34:28
Speaker 1: There's like two kinds of centaurs. I don't know which
34:30
Speaker 1: ones are the good ones and which ones are the
34:31
Speaker 1: evil ones or if it's much more nuanced than that,
34:34
Speaker 1: but there are red and there are blue centers. Thing. Wait, um,
34:38
Speaker 1: so we don't have a photograph of them, but we
34:41
Speaker 1: can tell from the light that they they reflect what
34:44
Speaker 1: color they are, Like they look like pin points, but
34:46
Speaker 1: like a red pin point and a blue pin point sometimes. Yeah,
34:50
Speaker 1: just like when you look at the night sky, you
34:51
Speaker 1: can tell which planet is Mars because it actually looks
34:55
Speaker 1: red to the naked eye, even though your naked eye
34:58
Speaker 1: can't really like see the size of Mars. You can
35:01
Speaker 1: still measure the light that comes from a pin prick,
35:04
Speaker 1: and that's the limitation of our knowledge about space center.
35:06
Speaker 1: So far. We basically just see them as pin pricks
35:09
Speaker 1: in telescopes because we've never done a close up fly by.
35:13
Speaker 1: And now there's also a little bit of controversy about
35:17
Speaker 1: these objects, yeah, because the color is an important clue.
35:20
Speaker 1: Like one question we'd like to ask is where did
35:22
Speaker 1: these things come from? Where were they made? Because remember,
35:25
Speaker 1: we're interested in studying the Solar System not just because
35:28
Speaker 1: stuff out there in space is cool it is, but
35:30
Speaker 1: because we think it tells us a story about how
35:33
Speaker 1: the Solar System was formed and what happened and where
35:36
Speaker 1: everything came from and whether it was unusual. And we
35:39
Speaker 1: think that a lot of these objects can tell us
35:41
Speaker 1: about that story based on where they are now and
35:44
Speaker 1: the way we do that as we build a complete
35:46
Speaker 1: model of how the Solar System was formed and we
35:48
Speaker 1: try to compare what that predicts to what we actually
35:51
Speaker 1: see out there in space, and where there's something we
35:54
Speaker 1: don't understand that tells us that something in our model
35:56
Speaker 1: is wrong, and so we're interested in, like where did
35:59
Speaker 1: these space guitars form? Do they form with the asteroids
36:03
Speaker 1: and then get sort of knocked out into weirder, longer orbits,
36:06
Speaker 1: or did they form with the comets and somehow get
36:09
Speaker 1: preferentially selected and pulled into the inner Solar system somehow?
36:13
Speaker 1: And so one great way to do that is to
36:15
Speaker 1: look at their composition. And we can't really do that
36:18
Speaker 1: without sampling them, but we can get a clue by
36:20
Speaker 1: looking at their light, so looking at whether they reflect
36:23
Speaker 1: red or blue light and comparing that to what we
36:26
Speaker 1: see from other parts of the Solar system. Like you
36:30
Speaker 1: might think, well, if these things are red and blue,
36:33
Speaker 1: what else out there is red and blue? And if
36:35
Speaker 1: you look at the Kuiper Belt, where we think that
36:37
Speaker 1: these things might come from, we find that those objects
36:40
Speaker 1: are not actually by colored. There aren't red and blue
36:43
Speaker 1: objects out there in the Kuiper Belt. Wait, if something
36:46
Speaker 1: is red and blue, would it be purple? Can there
36:50
Speaker 1: be purple centaurs? If not purple purple dragons? No, we
36:54
Speaker 1: mean that the Kuiper Belt doesn't necessarily have like a
36:57
Speaker 1: distribution of colors the way we see in centaurs, like
37:00
Speaker 1: centers tend to be red or blue. You don't have
37:03
Speaker 1: an individual center that's red and blue. You have red
37:06
Speaker 1: centaurs and blue centaurs, but if you look out in
37:08
Speaker 1: the Kuiper Belt, you don't see red objects and blue objects.
37:12
Speaker 1: So it suggests that that maybe they don't come from
37:14
Speaker 1: the Kuiper Belt. Maybe they come from somewhere else, like
37:17
Speaker 1: maybe they are not evenly distributed, like maybe they come
37:21
Speaker 1: from one of two places, yeah, Or maybe there's some
37:24
Speaker 1: process which is related to their composition which preferentially selects them.
37:28
Speaker 1: And there's this whole other group of objects out there.
37:31
Speaker 1: The Kuiper Belt is part of this set of objects
37:34
Speaker 1: we called trans neptunity and objects basically anything out there
37:38
Speaker 1: past Neptune. And in that group of stuff, there's a
37:42
Speaker 1: group of objects called plutinos, which are basically the category
37:46
Speaker 1: of objects that Pluto is in. You know, dwarf planets
37:50
Speaker 1: out there really far in the Solar System, and those
37:53
Speaker 1: things tend to have interesting colors. Like you remember when
37:56
Speaker 1: we did that fly by Pluto. One of the big
37:58
Speaker 1: shocks was frankly, how interesting Pluto was to look at.
38:02
Speaker 1: Are we sorry we downgraded it now they're like, oh,
38:06
Speaker 1: you're kind of cooler than we thought. We're sorry we
38:08
Speaker 1: kick you out of our club. Yeah, I think that's
38:10
Speaker 1: what happens when you kick somebody at your best friends
38:12
Speaker 1: club and then you discover they actually really talented and
38:14
Speaker 1: you wish you had stayed friends with them. That Pluto
38:17
Speaker 1: has these really interesting features. It's really interesting colors, and
38:20
Speaker 1: it has this heart shaped pattern on it. It's a
38:22
Speaker 1: pretty beautiful planet, actually non planet, non planet, thank you
38:26
Speaker 1: very much, as a dwarf planet. And a lot of
38:28
Speaker 1: these plutinos out there have interesting colors, and so those
38:31
Speaker 1: things tend to have both red and blue colors. So
38:35
Speaker 1: it might be that these centaurs used to be plutinos
38:38
Speaker 1: that used to be objects out there past Pluto and
38:42
Speaker 1: somehow got knocked in words by some process we don't understand. Now,
38:47
Speaker 1: can I actually see uspace on center with my naked eye,
38:50
Speaker 1: Like if I look out into the night sky, is
38:51
Speaker 1: it possible that I might see one going by? No,
38:54
Speaker 1: they tend to be further out and they're too small,
38:56
Speaker 1: so you definitely need a telescope to see one, the
38:59
Speaker 1: same way that you and see asteroids with your naked eye.
39:01
Speaker 1: And asteroids are sometimes even bigger than space centers and
39:04
Speaker 1: it's closer in, So if you see one with your
39:07
Speaker 1: naked eye. It means we're in trouble. Runaway, runaway to Mars. Maybe, Yeah,
39:14
Speaker 1: quick build that ship. All right, Well, that is what
39:18
Speaker 1: a space center is. It's um a sort of a
39:21
Speaker 1: half asteroid, half common but not really. It makes just
39:24
Speaker 1: sort of like a fuzzy object that falls in between
39:27
Speaker 1: the two. And so we see that the stuff out
39:29
Speaker 1: there in the Solar System can't be nicely categorized into
39:33
Speaker 1: little bins. That makes sense. There's stuff out there that,
39:35
Speaker 1: you know, might be a planet, might be a star,
39:37
Speaker 1: might be a dwarf planet. But there's an incredible variety
39:40
Speaker 1: of stuff out there for us to identify and to
39:43
Speaker 1: learn from. Yeah, I think the cool thing is that
39:45
Speaker 1: there are still things out there, even in our Solar
39:48
Speaker 1: System that kind of defied definition or that still kind
39:52
Speaker 1: of surprises or still has this talking about what's out
39:54
Speaker 1: there and how it all came to be. Yeah, and
39:56
Speaker 1: the far reaches of the Solar System are not very
39:59
Speaker 1: well explored. This trans Neptunian objects and stuff out there
40:02
Speaker 1: past Pluto is too far for us to see most
40:05
Speaker 1: of it, and we haven't sent very many probes, and
40:08
Speaker 1: so we're constantly surprised whenever we learned about them, and
40:11
Speaker 1: I think there are a lot more surprises out there
40:13
Speaker 1: waiting for us. And you know, even further out the
40:16
Speaker 1: Orc cloud. Remember that's something we've never actually seen. It's
40:19
Speaker 1: just theoretical. And when it's just theoretical, that means there
40:23
Speaker 1: are definitely surprises waiting for us. Oh yeah, what could
40:26
Speaker 1: there be? There could be interesting new things and maybe
40:29
Speaker 1: some of our listeners could discover one day armies of
40:33
Speaker 1: elves waiting to take back the Solis. Yeah. Yeah, what
40:36
Speaker 1: do you call a half common half planet, Daniel or
40:39
Speaker 1: a half moon have planetoid? I call it an ambush
40:43
Speaker 1: waiting to happen. They call it a future Nobel prize
40:45
Speaker 1: for somebody that's listening to this. All right, Well, the
40:48
Speaker 1: next time you look up at the night guy, think
40:49
Speaker 1: about it. There might be a Centaurs out there, or
40:52
Speaker 1: even new undiscovered objects at b B you could name,
40:57
Speaker 1: or at least fantasized about naming. And please be responsible
41:01
Speaker 1: with your future astronomical namings because we might have to
41:03
Speaker 1: cover it on the podcast. Yep. All right, Well we
41:06
Speaker 1: hope you enjoyed that. Thanks for joining us, see you
41:09
Speaker 1: next time. Thanks for listening, and remember that Daniel and
41:19
Speaker 1: Jorge Explain the Universe is a production of I Heart
41:22
Speaker 1: Radio or more podcast from my heart Radio. Visit the
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41:29
Speaker 1: to your favorite shows.