WEBVTT - Is our solar system weird? 0:00:09.680 --> 0:00:12.160 Ay, Daniel, When you were growing up, when did you 0:00:12.240 --> 0:00:16.040 first realize that the rest of the world was not 0:00:16.480 --> 0:00:20.760 like the neighborhood you lived in. Mmm, well, I grew 0:00:20.840 --> 0:00:23.520 up in Los Alngos, where I was surrounded by people 0:00:23.560 --> 0:00:27.080 with pH d s, and now I live on campus 0:00:27.120 --> 0:00:30.680 at you see Irvine, also surrounded by people with PhDs. 0:00:31.040 --> 0:00:33.519 Are you saying that's not typical? First of all, I 0:00:33.560 --> 0:00:37.680 feel a little sad for you. The second, I think 0:00:37.680 --> 0:00:40.559 maybe you need to travel more. Hey, I mean I 0:00:40.600 --> 0:00:43.559 have lots of friends who don't have PhDs like me, 0:00:43.560 --> 0:00:47.280 And you mean you do know I have a PhD. Right, Oh, 0:00:47.320 --> 0:00:50.640 that's true. Actually, well, I'm sure one of my friends 0:00:50.720 --> 0:00:54.560 out there doesn't have a PhD in something. Probably sometimes 0:00:54.600 --> 0:00:57.360 you have to leave your comfort zone to discover what 0:00:57.520 --> 0:01:00.520 the rest of the world or the universe is. Like. 0:01:17.200 --> 0:01:19.480 Hi am or hand Ma cartoonists and the creator of 0:01:19.600 --> 0:01:24.000 PhD comics. Hi, I'm Daniel. I'm a particle physicist by 0:01:24.120 --> 0:01:27.120 day and a podcaster by night. It makes it sound 0:01:27.160 --> 0:01:29.840 like you're a superhero. Like you you put on a 0:01:29.880 --> 0:01:34.080 costume and you go and fight crime and discover things. Wait, 0:01:34.120 --> 0:01:36.320 which is the alter ego and which is a superhero. 0:01:36.440 --> 0:01:42.400 Ag are you saying particle physicists are superheroes or podcasters? Well, 0:01:42.440 --> 0:01:44.800 since I'm not a physicist, I would say the podcasters 0:01:44.800 --> 0:01:49.000 are the superhero. That's right. By day, a boring, run 0:01:49.000 --> 0:01:51.560 of the mill particle physicists like the kind you meet 0:01:51.600 --> 0:01:54.600 at your grocery store every day. No more like during 0:01:54.600 --> 0:01:59.680 the day. You're a physicist scientists supervillain during night, then 0:01:59.680 --> 0:02:02.800 you try to fix fixed by being a podcaster. That's right, 0:02:02.840 --> 0:02:06.160 And I take off my glasses to reveal my secret 0:02:06.200 --> 0:02:10.560 podcast identity. You shave your beard every night never. That 0:02:10.720 --> 0:02:13.840 is the source of my knowledge and inspiration, source of 0:02:13.880 --> 0:02:18.280 your source of professor male professor's powers. That's right. I 0:02:18.320 --> 0:02:23.080 am the Samson of physics. Before I grew this beard, 0:02:23.120 --> 0:02:26.000 I never achieved anything in science. Oh man, what if 0:02:26.000 --> 0:02:28.440 you could a got Does that cut your productivity? You 0:02:28.520 --> 0:02:33.240 can have? It's nonlinear. Well, welcome to our podcast, Daniel 0:02:33.280 --> 0:02:36.200 and Jorge Explain the Universe, a production of I Heart 0:02:36.280 --> 0:02:39.680 Radio in which we tackle all things about the universe 0:02:39.680 --> 0:02:42.799 that are mysterious, that are amazing, that are bonkers, from 0:02:42.800 --> 0:02:45.320 how the universe was formed, to how big is it? 0:02:45.480 --> 0:02:47.840 To how old the Earth is, to whether or not 0:02:48.000 --> 0:02:52.080 your facial hair determines your evil or innocence yep. Or 0:02:52.080 --> 0:02:55.080 whether being a podcaster makes you a superhero or not. 0:02:56.720 --> 0:02:59.359 I think we all know the answer to that one. 0:03:00.320 --> 0:03:02.799 But basically, we talk about all the things that are 0:03:02.960 --> 0:03:08.120 interesting and different and fascinating about our universe right especially 0:03:08.160 --> 0:03:10.520 the things around us, and we try to focus on 0:03:10.560 --> 0:03:13.680 the things that science is asking right now, the questions 0:03:13.760 --> 0:03:16.040 in the minds of scientists. We try to take you 0:03:16.240 --> 0:03:19.600 to the cutting edge of current science and then do 0:03:19.800 --> 0:03:24.000 obscurify it. We don't use complicated words like de obscurify. 0:03:24.080 --> 0:03:28.160 We try to make things clear and understandable. You just 0:03:28.200 --> 0:03:31.360 contradicted yourself there. I feel like we try to explain 0:03:31.440 --> 0:03:33.840 things in the simplest way possible. When we explain it 0:03:33.880 --> 0:03:37.960 are explaining, we use the most complicated words possible. Hey, 0:03:38.000 --> 0:03:40.480 this is Daniel Jorge explained the universe, not Daniel Jorge 0:03:40.560 --> 0:03:44.280 explained the explaining and then welcome through new podcast Daniel 0:03:44.280 --> 0:03:47.520 and Jorge explain. Daniel and Jorge explain the universe. That's right, 0:03:47.640 --> 0:03:50.560 the spinoff podcast exactly. I'm looking forward to that one. 0:03:50.680 --> 0:03:52.840 A lot of TV shows now having like an aftershow, 0:03:53.640 --> 0:03:57.240 So that's the better off solid podcasts. Yeah, let's talk 0:03:57.360 --> 0:04:02.920 Daniel and Jorge podcast. Doesn't that need to have somebody 0:04:02.920 --> 0:04:04.720 else on it though, where they can ridicule all of 0:04:04.720 --> 0:04:09.880 our jokes. Yeah, let's pretend to be some other person. Oh, 0:04:09.920 --> 0:04:12.160 there you go. I'll be David and you'll be Gearmo. 0:04:12.440 --> 0:04:19.599 David and Jose. David Jose ridiculed Daniel and Jorge. Al right, well, yeah, 0:04:19.640 --> 0:04:21.800 we talked about all the things scientists want to know 0:04:22.200 --> 0:04:26.000 and um and how they look at the universe as well, right, Like, 0:04:26.120 --> 0:04:28.400 you know, one way to look at the universe is 0:04:28.440 --> 0:04:31.440 to compare it to the things around us. That's right, 0:04:31.520 --> 0:04:34.839 and something we're always trying to do in sciences. Understand 0:04:35.279 --> 0:04:38.680 our context is understand where we live, because hey, this 0:04:38.760 --> 0:04:41.599 is our planet in our solar system. We'd like to 0:04:41.680 --> 0:04:44.200 know is the rest of the of the universe similar 0:04:44.240 --> 0:04:47.479 to what we're finding around us or is it totally different? Yeah, 0:04:47.520 --> 0:04:50.960 because we like the Earth presumably, and it's pretty comfortable. 0:04:51.200 --> 0:04:55.039 And I'm pro Earth. Your pro it's pretty I'm taking 0:04:55.040 --> 0:04:58.200 a controversial opinion here at night, you're pro probably during 0:04:58.240 --> 0:05:01.679 the day your entire Earth. Well, it's not like particle 0:05:01.720 --> 0:05:04.400 physicists threatened to destroy the universe at any moment, so 0:05:05.480 --> 0:05:10.160 on purpose, right, Hey, intentions matter. Okay, I'm sure they 0:05:10.200 --> 0:05:14.440 matter once we're all made out of dissolved particles now. 0:05:14.440 --> 0:05:16.520 But we want to understand the world around us, and 0:05:16.560 --> 0:05:18.800 we want to understand if there are other worlds out there, 0:05:18.839 --> 0:05:21.080 and we'd also just like to know is the thing 0:05:21.120 --> 0:05:24.320 that we've been studying for the entire history of science 0:05:24.680 --> 0:05:27.800 is it normal? Is it typical? Or are we studying 0:05:27.839 --> 0:05:30.240 something which turns out to be really unusual and that 0:05:30.279 --> 0:05:33.359 we can't generalize from to get sort of deeper truths 0:05:33.400 --> 0:05:35.920 about the nature of the universe. Yeah, we like the Earth, 0:05:36.040 --> 0:05:39.120 we like our solar system, but um is the rest 0:05:39.120 --> 0:05:41.920 of the universe like us. And we're an amazing moment 0:05:42.000 --> 0:05:44.760 in human history when we're for the first time really 0:05:44.800 --> 0:05:47.760 getting glimpses for what the rest of the universe looked like. 0:05:47.880 --> 0:05:50.159 You know, for thousands of years, all we could see 0:05:50.160 --> 0:05:51.800 where other stars, but didn't even know if there were 0:05:51.839 --> 0:05:54.839 other planets out there. And then fairly recently in human history, 0:05:54.880 --> 0:05:57.240 thousands of years ago we discovered that there are other 0:05:57.320 --> 0:06:00.680 planets out there. And now super recently, just like twenty 0:06:00.760 --> 0:06:04.560 years ago, we've begun seeing planets around other stars. So 0:06:04.600 --> 0:06:07.159 we can now ask and answer this question people have 0:06:07.200 --> 0:06:10.880 been wondering about four thousands and thousands of years. So 0:06:10.920 --> 0:06:18.839 today on the podcast, we'll be asking the question, is 0:06:18.880 --> 0:06:23.240 our solar system weird or typical? And either way we 0:06:23.360 --> 0:06:26.080 love it. Right, it's our solar system, whatever label you 0:06:26.120 --> 0:06:28.719 put on it, we like it. But we're still curious. 0:06:29.160 --> 0:06:31.560 Is it sort of the oddball solar system it's the 0:06:31.600 --> 0:06:33.919 only one we've been studying for a long time, or 0:06:34.040 --> 0:06:36.880 is it pretty typical? Yeah, this is a really cool question. 0:06:37.080 --> 0:06:39.560 And because you know, I think we grew we grew 0:06:39.640 --> 0:06:43.080 up in this solar system, right, and we don't have 0:06:43.160 --> 0:06:46.240 we have no idea whether it's every other solar system 0:06:46.279 --> 0:06:49.440 looks like this one, or whether we're like, it's really weird, 0:06:49.640 --> 0:06:55.520 odd special gem or disaster, depending on how things work 0:06:55.560 --> 0:06:58.720 out of a solar system. Yeah, and it's all we 0:06:58.760 --> 0:07:00.800 could have studied for the long this time because our 0:07:00.800 --> 0:07:03.960 telescopes couldn't see any further, so we were limited to 0:07:04.080 --> 0:07:07.080 only looking at our cosmic neighborhood, to studying our planet 0:07:07.320 --> 0:07:09.560 and the ones nearby, and so of course we were 0:07:09.600 --> 0:07:11.480 curious what else was out there in the rest of 0:07:11.480 --> 0:07:14.320 the universe. But imagine if you had only lived in 0:07:14.360 --> 0:07:17.200 your hometown your whole life, and you never received any 0:07:17.240 --> 0:07:19.600 news in the outside world, and so you didn't know 0:07:19.680 --> 0:07:22.520 that people eight differently in other countries, and people went 0:07:22.560 --> 0:07:25.000 to the bathroom differently in other countries, and dressed differently 0:07:25.000 --> 0:07:28.160 and spoke differently. You imagined that everything else in the 0:07:28.160 --> 0:07:31.360 world was sort of like your hometown. That's where we 0:07:31.400 --> 0:07:34.200 are right now in science we're wondering if those other 0:07:34.240 --> 0:07:38.320 solar systems are totally different or just the same as ours. Yeah, 0:07:38.360 --> 0:07:40.800 you're saying humanity sort of like a like those mirror 0:07:40.840 --> 0:07:45.040 cats you've seen documentaries. We were just finally sticking our 0:07:45.040 --> 0:07:47.000 head out of the hole in the ground that we've 0:07:47.000 --> 0:07:49.840 been living in and looking around this. Yeah, but we've 0:07:49.840 --> 0:07:52.000 been desperate to do it for for a long time, 0:07:52.040 --> 0:07:54.680 and we've only recently built a technology that's let us 0:07:54.920 --> 0:07:57.840 see other solar systems and start to get an answer 0:07:57.880 --> 0:07:59.720 to this question, because you know, I feel like most 0:07:59.720 --> 0:08:02.320 people just assume that the rest of the universe looks 0:08:02.400 --> 0:08:06.040 like our solar system and our planet, right Like, if 0:08:06.040 --> 0:08:09.360 you look at most science fiction TV shows and movies, 0:08:09.720 --> 0:08:12.600 you know, everywhere they go, it sort of looks suspiciously 0:08:12.680 --> 0:08:16.480 like Earth. Yeah, And I think that's a failure of imagination, 0:08:16.600 --> 0:08:18.960 especially on the part of science fiction. When you fly 0:08:19.000 --> 0:08:21.480 to another planet and you know, hey, it has oxygen 0:08:21.560 --> 0:08:24.200 on it and trees and hills and water that looks 0:08:24.240 --> 0:08:26.440 just like ours, and oh, people on it that look 0:08:26.520 --> 0:08:29.520 just like ours, but their foreheads are slightly wrinkly. I 0:08:29.560 --> 0:08:32.360 think that's a failure of imagination. But it's also sort 0:08:32.400 --> 0:08:37.240 of understandable because it's hard to imagine things totally different 0:08:37.280 --> 0:08:40.480 from anything you've ever seen before. That's why good science 0:08:40.520 --> 0:08:43.079 fiction is rare. Did you just insult All Star Trek 0:08:43.280 --> 0:08:45.480 and Star Wars that was supposed to be sort of 0:08:45.480 --> 0:08:48.440 like a subtweet? Didn't mention it by name, but yeah, yeah. 0:08:48.480 --> 0:08:50.920 And so the question is are those science fiction movies right? 0:08:51.080 --> 0:08:55.040 Are Are there really other earths out there? Are other 0:08:55.080 --> 0:08:58.960 solar systems like ours? Or are we unique in this universe? 0:08:59.000 --> 0:09:01.760 And so, as usual, we were wondering how what people 0:09:01.800 --> 0:09:05.120 thought about this question, whether people thought that we are 0:09:05.200 --> 0:09:08.120 unique or whether things are very different out there in 0:09:08.120 --> 0:09:10.760 the verse. So I walk around campus and I asked 0:09:11.120 --> 0:09:15.120 random students about other random solar systems. I think, for 0:09:15.160 --> 0:09:18.800 a moment, do you think other solar systems look like ours? 0:09:18.880 --> 0:09:21.760 Is our solar system typical or is our solar system 0:09:21.760 --> 0:09:25.000 going to turn out to be really weird? The galactic oddball. 0:09:25.200 --> 0:09:27.320 Here's what people had to say. From what I know, 0:09:28.559 --> 0:09:31.680 it's typical. Um, I mean it depends what you say. 0:09:31.760 --> 0:09:38.200 Typical is considering there billions of stars, but it's not unusual. No, 0:09:38.320 --> 0:09:41.160 I have no idea. It's probably random. If there were 0:09:41.360 --> 0:09:43.560 gases on a planet that were closer to the Sun 0:09:43.679 --> 0:09:46.600 or like star, maybe they would like dissipate faster. I 0:09:46.600 --> 0:09:51.680 think that it's ranks. I think you say I do 0:09:51.760 --> 0:09:54.079 not know. I think it's random, and I think it's 0:09:54.080 --> 0:09:58.360 going to be different Because our solar system it revolves 0:09:58.400 --> 0:10:00.640 around the Sun. I think other systems are gonna be different. 0:10:00.840 --> 0:10:02.959 So what do you think of those answers? Or pretty good? 0:10:03.000 --> 0:10:06.560 I thought I felt like people had a strong opinion 0:10:06.600 --> 0:10:10.600 about this topic. You know, everyone said I think it's X. 0:10:11.480 --> 0:10:14.240 Nobody said I don't know or only one. Only a 0:10:14.240 --> 0:10:16.080 few people said I had no idea, But a lot 0:10:16.080 --> 0:10:17.679 of people that were like, I think I have an 0:10:17.679 --> 0:10:20.320 opinion about this. Yeah, given that nobody really knows the 0:10:20.360 --> 0:10:22.760 answer to this question, I was a little surprised at 0:10:22.760 --> 0:10:25.240 the strength of people's opinions. I mean, I often ask 0:10:25.280 --> 0:10:28.040 people questions and they go, I have no idea quantum what. 0:10:28.520 --> 0:10:30.679 But this time people had an opinion. And maybe that's 0:10:30.679 --> 0:10:33.560 just because people have thought about this. They've wondered what 0:10:33.640 --> 0:10:36.800 other solar systems look like. They've thought about traveling to 0:10:36.840 --> 0:10:39.320 the stars and walking on those planets and wondered if 0:10:39.360 --> 0:10:41.760 they would be like ours. I wonder if you would 0:10:41.800 --> 0:10:44.240 get different answers if you caveat each time you ask 0:10:44.400 --> 0:10:47.360 these questions, If you caveat them with oh, and by 0:10:47.360 --> 0:10:49.360 the way, some of the smartest people in the world 0:10:49.440 --> 0:10:52.400 don't know the answer to this, I would be so 0:10:52.520 --> 0:10:57.280 much less fun. Who would want to answer that? Nobody? 0:10:58.600 --> 0:11:01.200 I love when people speculated. I of seeing them in 0:11:01.240 --> 0:11:03.960 their minds sort of take this question on and sometimes 0:11:04.000 --> 0:11:06.520 for the first time and formulate an answer. And my 0:11:06.600 --> 0:11:08.840 favorite moments are when you can see somebody giving an 0:11:08.840 --> 0:11:12.280 answer that sort of surprises themselves. They think about it, 0:11:12.280 --> 0:11:13.920 they give an answer that, oh, I didn't realize I 0:11:13.960 --> 0:11:16.800 do think that. That's fascinating. Makes me wonder how much 0:11:16.920 --> 0:11:22.000 we actually think about the things we say. Sometimes I'm 0:11:22.000 --> 0:11:23.880 just listening to my own self talking, I'm like, what 0:11:23.920 --> 0:11:26.160 did he just say? So that's the question of the day. 0:11:26.360 --> 0:11:30.920 Is is our solar system unique? Or is it pretty typical? 0:11:31.520 --> 0:11:34.000 And if it's not typical, how different could it be 0:11:34.200 --> 0:11:36.800 out there? And you should count yourself lucky to live 0:11:36.840 --> 0:11:39.040 in a time when we will know the answer to 0:11:39.080 --> 0:11:44.240 this question. Some of the greatest minds in history, Galileo Einstein, Newton, 0:11:44.360 --> 0:11:46.840 even recent people like Richard Feynman, they looked up at 0:11:46.840 --> 0:11:49.240 the stars and they wondered if other solar systems look 0:11:49.320 --> 0:11:52.720 like ours. They all died not knowing the answer. All 0:11:52.760 --> 0:11:55.120 you have to do is listen to this podcast. Yeah, 0:11:55.200 --> 0:12:00.599 so you're welcome. Are you taking it for all the 0:12:00.640 --> 0:12:03.520 scientific discoveries? Thank you? Or hey who personally built the 0:12:03.559 --> 0:12:06.319 Hubble space telescope with his own hands? I signed the 0:12:06.320 --> 0:12:08.480 back of it. I don't know if anyone will ever 0:12:08.679 --> 0:12:11.120 you drew a doodle on it? Are you the official 0:12:11.120 --> 0:12:14.560 cartoonist of the space telescope? Technically you can't prove that 0:12:14.600 --> 0:12:16.640 I didn't sign the back of the Hubble telescope. Oh 0:12:16.760 --> 0:12:20.320 I need another telescope trained on the space telescope to 0:12:20.320 --> 0:12:21.959 see the back of it. I wonder if anybody ever 0:12:22.000 --> 0:12:23.760 does that, But yeah, do you think so? Yeah, it's 0:12:23.800 --> 0:12:25.760 an interesting question. I'm sure a lot of people have 0:12:25.920 --> 0:12:28.920 asked before. So let's break it down for people, Daniel. 0:12:29.000 --> 0:12:32.320 Let's talk about our solar system, and then let's talk 0:12:32.360 --> 0:12:35.400 about what other solar system. Well, we know about other 0:12:35.440 --> 0:12:39.400 solar systems out there, right, and our solar system is 0:12:39.440 --> 0:12:42.800 actually quite fascinating because it has some sort of trends 0:12:42.840 --> 0:12:45.480 in it. And you have to remember that all of 0:12:45.520 --> 0:12:47.840 our knowledge of solar systems and how they're formed, all 0:12:47.840 --> 0:12:51.120 of our theories how solar systems were built, have been 0:12:51.160 --> 0:12:54.000 developed over decades or hundreds of years based on just 0:12:54.080 --> 0:12:58.079 this one example, our solar system. So you know, we 0:12:58.160 --> 0:13:01.680 sort of tuned these theories to describe what we've seen here, 0:13:01.800 --> 0:13:04.000 and now comes the big test to see whether these 0:13:04.080 --> 0:13:07.200 theories can be applied and explain other solar systems, right, 0:13:07.200 --> 0:13:09.440 Because I think maybe people a lot of people don't 0:13:09.440 --> 0:13:13.360 realize that we can't. Just up until very very recently, 0:13:13.400 --> 0:13:16.320 and only just now barely, we haven't really been able 0:13:16.400 --> 0:13:19.400 to like take a telescope pointing at another star and 0:13:19.720 --> 0:13:23.319 see another solar system, right like it's up until very 0:13:23.400 --> 0:13:26.760 very recently, it's been a complete mystery. What other solar 0:13:26.800 --> 0:13:29.600 systems look like? Yeah, the first planet around another star 0:13:29.800 --> 0:13:32.840 was seen just over twenty years ago, so it's a 0:13:32.920 --> 0:13:36.040 blip in human history and even in scientific history. But 0:13:36.200 --> 0:13:38.320 even before we talk about the other solar systems, our 0:13:38.360 --> 0:13:41.480 solar system is interesting, like there are some weird trends 0:13:41.480 --> 0:13:43.880 in it. You know, the first four planets in the 0:13:43.880 --> 0:13:47.240 Solar System are all rocky planets. Planets basically come in 0:13:47.280 --> 0:13:51.319 two flavors, rocky or gassy. It sounds like sounds like 0:13:51.360 --> 0:13:55.880 a bad ice cream shop. Yeah, like like like what 0:13:55.960 --> 0:13:57.959 happens when I like those into olm prison goes to 0:13:58.000 --> 0:14:01.480 an ice cream shop? Yeah, well, the first four planets 0:14:01.520 --> 0:14:04.480 have surfaces on them, right, You've got Mercury, Venus, Earth, 0:14:04.480 --> 0:14:07.760 and Mars. These are basically balls of rock, rock and metal. 0:14:08.280 --> 0:14:11.080 And so we call those rocky planets. And there's no 0:14:11.200 --> 0:14:13.760 gas planets in the inner flour And said, you know 0:14:13.840 --> 0:14:16.320 the four rocky planets, then you have the asteroid belt 0:14:16.320 --> 0:14:18.520 that we dug into in a recent episode. And then 0:14:18.640 --> 0:14:21.200 after the asteroid belt, you've got the gas giants and 0:14:21.200 --> 0:14:23.880 the ice giants. You got Saturned, You've got Jupiter, you've 0:14:23.880 --> 0:14:26.880 got Urinus and Neptune, and those are pretty different from 0:14:26.920 --> 0:14:28.960 the inner planets. Is there a reason we don't have 0:14:29.120 --> 0:14:33.040 liquid planets or like wet planets or like giant balls 0:14:33.080 --> 0:14:36.080 of of a liquid floating around. Well, we can't have 0:14:36.280 --> 0:14:38.800 liquid planets. In the far Solar System. We have basically 0:14:38.880 --> 0:14:41.240 ice giants Uranus and Neptune. A huge fraction of them 0:14:41.280 --> 0:14:43.200 is made of water, but it's frozen. Of course, it's 0:14:43.200 --> 0:14:45.640 too cold out there. There is of course water here 0:14:45.680 --> 0:14:47.720 on Earth. But could you have just like an entire 0:14:47.840 --> 0:14:50.400 drop of water be a planet, that would be pretty amazing. 0:14:50.440 --> 0:14:53.840 I think the pressure from it would probably crystallize the inside. 0:14:53.880 --> 0:14:57.320 So basically become an ice planet with a ocean around it, 0:14:58.000 --> 0:15:02.080 kind of like a Europa or what's what's the wound 0:15:02.120 --> 0:15:05.280 that's like a giant ocean. Yeah, Europa has a huge, 0:15:05.320 --> 0:15:08.680 actually thick crust of ice on top and then a 0:15:08.800 --> 0:15:11.720 layer of water underneath, like an ocean underneath, and then 0:15:11.800 --> 0:15:13.760 we don't know what's inside of that. So that's like 0:15:13.800 --> 0:15:15.840 an eminem sort of. But as the reason we don't 0:15:15.840 --> 0:15:19.480 have liquid planets, just just depending on the elements that 0:15:19.520 --> 0:15:21.520 we have in our Solar system, I don't think you 0:15:21.560 --> 0:15:25.400 can make a blob of of liquid water large enough 0:15:25.760 --> 0:15:28.320 stay liquid because the core of it would just be 0:15:28.320 --> 0:15:30.400 too dense. It would form a solid, like by the 0:15:30.440 --> 0:15:32.640 time it got big enough to be called the planet, 0:15:33.120 --> 0:15:35.760 would it would totally not be liquid. Yeah, the gravitational 0:15:35.800 --> 0:15:38.160 pressure would make the inside of it become a solid 0:15:38.280 --> 0:15:40.920 or or something more dense, so it wouldn't be liquid anymore. 0:15:41.120 --> 0:15:43.080 Do you have this fantasy of swimming through like a 0:15:43.120 --> 0:15:48.200 planet sized pool of water? The universe is biggest swimming pool. 0:15:48.200 --> 0:15:51.960 That would be pretty cool, nothing but a huge drop 0:15:51.960 --> 0:15:53.320 of water the size of the Earth and then a 0:15:53.360 --> 0:15:57.680 single diving boards. You're like, you think you have an 0:15:57.680 --> 0:16:02.920 infinity pool. I have a planet universe universe infinity pool. 0:16:03.960 --> 0:16:05.720 But no, we don't have any liquid planets in our 0:16:05.720 --> 0:16:08.920 solar system. But hey, maybe you know, we'll find planets 0:16:08.960 --> 0:16:11.040 in other solar systems that are liquids and that will 0:16:11.080 --> 0:16:14.040 prove us wrong, and maybe liquid planets are possible, but 0:16:14.080 --> 0:16:16.320 we don't happen to have any in our solar systems. 0:16:16.320 --> 0:16:19.240 That we have four rocky planets the asteroid belt and 0:16:19.280 --> 0:16:22.280 then the gas giants and the ice giants. And you're saying, 0:16:22.280 --> 0:16:24.080 that's kind of funny in that it's sort of like 0:16:24.120 --> 0:16:28.080 a pattern, like it's four rocky asteroid belt gas giants. 0:16:28.080 --> 0:16:32.960 It's not like rocky gas, rocky gas gas gas rocky. Yeah, 0:16:33.000 --> 0:16:36.000 it doesn't seem random. Here's a question from a listener, 0:16:36.040 --> 0:16:40.200 Camille who thought just the same thing. Hello, Danielle and Jey. 0:16:40.600 --> 0:16:43.160 One of the recent episodes I have listened to your show, 0:16:43.160 --> 0:16:46.000 which was all about the asteroid belt, you, daniel mentioned 0:16:46.000 --> 0:16:48.480 that there must be a reason why we have solid 0:16:48.640 --> 0:16:52.480 rocky planets before the asteroid belt and then only gas 0:16:52.520 --> 0:16:56.320 giants afterwards. But you never got to answering this question, 0:16:56.440 --> 0:16:58.360 is there a reason we know? Why? Is it like 0:16:58.480 --> 0:17:01.800 this that we see these kind of pattern other stuff? 0:17:02.040 --> 0:17:05.280 I'm dying to know. That's such a good point. Thank 0:17:05.320 --> 0:17:08.320 you Camille for sending in that question. And every time 0:17:08.359 --> 0:17:10.280 you see a pattern, you think maybe there's a reason 0:17:10.520 --> 0:17:12.680 and you want to untangle that reason. Now, it's very 0:17:12.800 --> 0:17:16.480 dangerous when you're drawing conclusions from one example. If you 0:17:16.560 --> 0:17:19.080 visit somebody's house and they're like, oh, look, their family 0:17:19.240 --> 0:17:22.080 is boy boy, boy, boy boy, girl, girl, girl, girl girl, 0:17:22.359 --> 0:17:24.359 you're going to conclude there's a reason, right that they 0:17:24.400 --> 0:17:26.440 all have younger girls and older boys. But if you're 0:17:26.440 --> 0:17:28.960 only looking at one house, you're gonna be totally wrong. 0:17:29.080 --> 0:17:32.480 That would be kind of impolite to ask Daniel. You're like, 0:17:32.520 --> 0:17:35.720 did you guys try are you're doing something different? You 0:17:35.720 --> 0:17:39.560 know when you um um, you know you'd be desperate 0:17:39.560 --> 0:17:43.640 to know though, you'd be super curious. And also, there's 0:17:43.680 --> 0:17:45.959 lots of families where it's like five boys and then 0:17:46.000 --> 0:17:47.600 a girl, and you know that they were trying for 0:17:47.640 --> 0:17:49.760 a girl and they finally got one and that's when 0:17:49.760 --> 0:17:52.119 they stopped having kids. That's when they're like, we're a 0:17:52.160 --> 0:17:55.800 closing shop. Yeah, so maybe our source systems close shops 0:17:55.840 --> 0:17:59.959 after after Neptune or uranus. We're done trying to make 0:18:00.000 --> 0:18:05.560 a liquid planet. It's not happening. We're sorry, we're trying 0:18:05.560 --> 0:18:07.679 to make a giant swimming pool, but you know, it 0:18:07.760 --> 0:18:09.720 just hasn't happened. That's right. The kid's gotta go swim 0:18:09.760 --> 0:18:12.320 somewhere else. But so we do have some explanations we've 0:18:12.359 --> 0:18:14.360 cooked up, but of course the proviso is, we don't 0:18:14.400 --> 0:18:16.399 know if this works until we try to apply to 0:18:16.440 --> 0:18:19.639 other solar systems. And the basic idea is that you 0:18:19.680 --> 0:18:23.879 don't get gas giants close into the sun because the 0:18:23.920 --> 0:18:26.800 Sun has all this radiation it spewing up the solar wind, 0:18:27.119 --> 0:18:30.800 and that basically blows out all the light elements, the hydrogen, 0:18:30.960 --> 0:18:32.919 the helium, all the stuff you need to make a 0:18:32.960 --> 0:18:35.560 gas giant, all the gas. It blows it away from 0:18:35.560 --> 0:18:37.800 the Sun. So that's why you don't have gas giants 0:18:37.800 --> 0:18:40.479 close up to their star. It's kind of like a cloud. 0:18:41.200 --> 0:18:42.840 It gets too close to the Sun, which is kind 0:18:42.840 --> 0:18:45.920 of wish evaprate. Yeah, and so that's sort of the 0:18:45.960 --> 0:18:49.199 explanation for why you have rocky planets close in. And 0:18:49.240 --> 0:18:52.520 then in the outer planets it's colder, and so instead 0:18:52.520 --> 0:18:54.720 of having liquid water, you have ice, and then that 0:18:54.840 --> 0:18:57.359 ice helps the core of the planet's form. You're like, 0:18:57.680 --> 0:19:00.159 you know, how does the planet form? Anyway, You the 0:19:00.200 --> 0:19:03.320 initial sort of disc of stuff from the that formed 0:19:03.320 --> 0:19:05.520 the whole Solar System, and some of it is spinning 0:19:05.600 --> 0:19:07.720 so it doesn't fall into the star. And then in 0:19:07.800 --> 0:19:10.520 the outer reaches, it's cold enough that you have ice 0:19:10.760 --> 0:19:13.879 and that helps accumulate the gravity very slowly gather the 0:19:13.920 --> 0:19:16.360 stuff together. Because you have ice out there, it can 0:19:16.359 --> 0:19:19.760 sort of add ice to your basic planet core and 0:19:19.800 --> 0:19:22.320 they can get big enough to suck up all the 0:19:22.400 --> 0:19:25.920 gas and the hydrogen in the helium. Because remember hydrogen 0:19:26.000 --> 0:19:28.480 helium is very light, which means it's hard to hold onto. 0:19:28.520 --> 0:19:31.679 You need a huge gravitational mass to attract that. So 0:19:31.720 --> 0:19:33.600 to make a gas giant, you have to form a 0:19:33.680 --> 0:19:37.040 really big core of some metals and some ice in 0:19:37.119 --> 0:19:38.960 order to pull in the rest of the gas. And 0:19:39.040 --> 0:19:41.280 that can only happen in the outer reaches of the 0:19:41.280 --> 0:19:43.879 solar system, where you have ice. And so the reason 0:19:43.960 --> 0:19:46.119 you get gas giants and the outer Solar system is 0:19:46.280 --> 0:19:49.200 because that's where the gas is and because that's where 0:19:49.200 --> 0:19:52.400 the ice is to help pull those light gases together 0:19:52.760 --> 0:19:55.240 into a gas giant. At least that's our theory, and 0:19:55.280 --> 0:19:57.879 that's based on just what we've observed, all right. So 0:19:58.200 --> 0:20:01.679 that explains why our solar system looks to wait us, 0:20:01.720 --> 0:20:05.360 why it's like rocky in the middle and then gassie 0:20:05.520 --> 0:20:08.560 out there in the edges of it. And so that's 0:20:08.640 --> 0:20:10.359 kind of the picture of our solar system. We have 0:20:10.400 --> 0:20:14.280 a yellow sun, some rocky planets, some asteroids, and then 0:20:14.480 --> 0:20:19.359 giant gas balls um swirling around the edges of them, precisely. 0:20:19.440 --> 0:20:22.240 And remember we've been aware of this for decades and 0:20:22.320 --> 0:20:24.920 decades and decades and so we had a long time 0:20:24.960 --> 0:20:27.440 to cook up this model based on just this one 0:20:27.600 --> 0:20:31.080 solar system. It's become very fine tuned and and very 0:20:31.080 --> 0:20:34.240 sort of baroque to explain exactly what we're seeing. And 0:20:34.280 --> 0:20:36.720 so now comes the test. Now we get to apply 0:20:36.840 --> 0:20:39.160 it to other solar systems and see if it also 0:20:39.200 --> 0:20:41.800 explains what we see out there. Yeah, all right, so 0:20:41.880 --> 0:20:45.840 let's get into what other solar systems look like. But 0:20:45.960 --> 0:21:01.320 first let's take a quick break. All right, we're talking 0:21:01.359 --> 0:21:04.199 about how our solar system may or may not be 0:21:04.280 --> 0:21:07.000 different than other solar systems out there, and we know 0:21:07.080 --> 0:21:09.199 that we have a pretty good picture you're saying, of 0:21:09.240 --> 0:21:11.320 our solar system, and it's taken as a while, but 0:21:11.400 --> 0:21:13.760 we can have a good idea of how our solar 0:21:13.800 --> 0:21:17.439 system formed sort of and or white looks like rocky 0:21:17.480 --> 0:21:20.440 planets and then gas giants. And so now the question 0:21:20.640 --> 0:21:23.800 is is this what other solar systems look like like? 0:21:23.840 --> 0:21:26.600