Are there planets without a star?

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Speaker 1: Hey, Daniel, did you ever want to be an astronaut? Well, yes, but I didn't because I'm terrified of the danger and the adventure. Yeah, I'm not ready to travel in the space until it's safe and routine. Yeah, it is pretty dark and scary out there, But isn't that kind of the point of space exploration to go out there and discover and find new things hiding in the darkness. Yeah, and I want other people to go out there take those risks, and then I can just read about it in the newspaper. Hi am or Handmay, cartoonist and the creator of PhD Comics. Hi. I'm Daniel Whitson. I'm a particle physicist, and I'm a stay at home adventurer of the mind couch Explorer. I'd like to explore this vast universe from the comfort of my office. But welcome to our podcast, Daniel and Jorge Explain the Universe, a production of I Heart Radio, in which we take you on an exploration of all the amazing, crazy, monkers, beautiful, nasty, crazy, weird things in this universe. Did I say crazy twice? That's because the universe is that crazy. It's double crazy. I feel like the things we're learning in science every year, every decade, every generation are crazier than the things we learned before. It's not just that we're learning more, but the stuff we're revealing is just more bonkers than anything we could have imagined. Don't you feel that way? Well, do you think it's crazier than what we thought it was before? You know, is it crazier than Greek gods and Norse mythology? Well, I think it's maybe less creative, but it's definitely crazier. Every generation has had to absorb ideas which were very difficult to swallow because they completely conflict with our view of the world. You know, the universe is expanding, there is no sense of location and time. You know, things are fundamentally random. Space curves like these are hard things to get your mind around, and they get harder and harder as we discover them. Yeah. We are not the center of the universe, and the universe is not like what we see around are where we are. Yeah, and every time we look out into space we discover new stuff, weird stuff. Places we thought were empty turned out to be filled with interesting, fascinating, weird kinds of matter. M Yeah, because that's kind of the history of humanity and science. Right, Like, we look around and we assume that the whole universe is kind of like where we're at. Right. We thought the world was flat because everything seems flat around us, And we thought that the Earth was the center of the universe because everything seems to provolve around this. But then as we learn more that we learn that there are more and more different things out there. We keep learning that the assumptions we make, that the generalizations we make about what we learned here, cannot be applied everywhere. And that's the exciting part. That's the moment of discovery, when you realize, oh, I thought the universe was this way. It turns out it's actually totally different in a way I never imagine. We're intellectually maturing as a species by discovering our universe and coming to grips with it. And it's not always the way we liked it, but it turns out to be quite fascinating to the other program will be tackling one such idea that you know, maybe a lot of people even today think is true, but actually it turns out to be much more complex than that. That's right, that darkness out there is more filled with interesting stuff and rocks than you could have ever imagined. Yeah, stuff that's out there hiding in the darkness, other worlds out there looking at ours and wondering what would it be like to be so close to a nice, warm, toasty star. Yeah. So today on the program, we'll be tackling the question are there planets without stars and not just a movie stars? Right? We're talking about are there places in the universe then don't have a son or a star near them? I like the one you asked though, Like, are their planets out there with only being C list actors? That's right? Where everyone uh it only has five seconds of fame. You can only be in one movie and then your career is over. It's like turn limits for for Hollywood actors. That's great, and then that'd be great if we got rid of celebrity culture in our society. Yeah, well, that won't appeal to any of our celebrity listeners, you know. So Hey Brad Pitt, don't worry. You can still come on the program. But apparently it works if you If you speak badly about somebody don't want to come on our show, then that's true. To defend themselves, maybe to grab any kind of publicity they can. That's true. Stay tuned for our episode in which science fiction authors come on the show and respond to our critiques. And when we're thinking about the broad universe, you know, you are used to thinking about your planet is having one very important feature, which is the on And every time you think about a planet, you imagine, well, planets form around stars, right, and so it's a bit mind bending to imagine that the universe might be different. Yeah, a lot of people might be surprised to learn that not every planet out there is centered around the star. You may be shocked to discover that rogue planets are not that rare. That the universe may be chalk filled with these floating dark bodies. Yeah, and that's the official physics name for them, right, like a planet without a star. It's officially called a rogue planet. Yes, but you will not be surprised to discover there is some controversy about what exactly gets called a rogue planet. Oh wow, physicists arguing about what to name something that's so rare, not only arguing about whether something is a good name, but like what exactly falls into this category? You know, the whole Pluto, like is it a planet? Is it not a planet? Thing? That's this same controversy large interesting because I guess everything is sort of being pulled by every star in the universe, So technically there there isn't this a planet that's not being pulled by a star. I like that. You're sort of saying every planet is part of a sum solar system, even if it's sort of distant from its star. Right, Well, technically, right, don't all solar systems sort of overlap with each other? Technically because the force of gravity is infinite has infinite reach. Yeah, that's true. The force of gravity is infinite, but at some point the force of gravity from these stars is basically negligible and there's essentially no effect on these planets, and they're more affected. Yeah, negligible, They're more affected by the mass of the galaxy. So I think the distinction is are you orbiting a star or are you orbiting the center of the galaxy? All right, Well, I was a little surprised to find out that there are road planets out there, and that there are apparently not just a few of them. But we were wondering how many people out there knew the same fact that there are planets out there in space without stars. So I walked around campus a you see, Irvine, and I asked folks what they thought and if they had a guess for how many rogue planets there might be in the universe. To think about it for a second, how many planets out there in the universe? Would you, guys are out there floating without a star. Here's what people had to say. I have no clue how many there are. My guests understanding from what I think I know is that they're by one way or another of something flying by the end up injected from the star that they'reth I have not do you think does exists? I don't think. I can't imagine that that would be not true, honestly, like a lot of just like ten, I would have no idea how to give a number, Um I would I would actually have to say probably a lot, just because gravity is so you can get a star really close to another set of planets and then it throws them off in space. So probably a lot, probably, I think. So you think it's like seven or like a billion? Jeeus? Um, Well, in a in a big universe, I don't know if we could count. No, I think every planet. I think interested pretty good mix of reactions. Yeah, a lot of open minds. I love the people who say the universe is so big you can never say no, you can never say that something doesn't exist. I think that's a great attitude because technically, in an infinite universe, anything can happen, right, and anything is happening. Yeah, in an infinite universe, everything that can happen eventually will happen and is happening somewhere. So it's a good attitude. Now, we don't know the universe is infinite, but it's definitely pretty big right somewhere out there. There's a version of this podcast in which you and I are the A List celebrities. That's not this version. What are you saying? I don't I'm confused. I think we're run out of letters letters. That's right with the Triple A. We're the Triple We're Triple A celebrities, which sounds good, but really, welcome to the minor the Ego podcast, folks. Yeah, so, um, but people seem sort of skeptical. I mean, some people said yes, but it sort of seemed like yes, probably, but probably it's probably not very common, that's right, and it's immediately a fascinating question. It's the kind of thing you might not ever think about. You think, oh, well, planet is of course they form around stars, and that's reasonable because stars form from the gravitational collapse of stuff, and plants do the same thing, and so you should imagine they formed together. They're probably associate with each other. You probably don't ever think that there are dark bodies floating out there in between the stars. But as soon as somebody suggested to you, then you have to wonder, well do we know, how do we know? Have we looked? Could we see them? And immediately it's a question you need to know the answer to. Yeah, because if it's a lot, then they would be pretty uh interesting, I guess, or dangerous because what if one of them hits us? Yeah, it's a little bit dangerous. But also it just changes sort of your your view of the universe. I mean, what if there are more rogue planets out there than non rogue planets, then your whole view of like what is a planet has to all of a sudden change from oh, they're all around stars to well, my sense of a planet is unusual is a typical? Oh I see, it could be that our kind of planet is the minority. Yeah, exactly, Just like we discovered that our kind of matter is a small fraction of all the matter in the universe. All of a sudden, things we thought were typical are now weird. It'd be like discovering their more continents out there. Or you know, you grow up in your family eats a dinner a certain way, and then you go to a friend's house you discover, oh man, my family is weird. We are and we don't use utensils at home or whatever it is. You know, it's it's maturing in that same way, right, It's expanding your horizon and your idea of the universe. And that's why this is such a fun opportunity to learn something new about the universe. All right, so let's get into it. Daniel Wood exactly is a rogue planet. Right, So let's begin with technical definitional stuff that we could argue about easily for half an hour. And and and very importantly, is there a first rogue planet called rogue one? Well, the movie rights for that one I've already been locked up, unfortunately. Yeah, Well they're not definitely not making a sequel of that one. I liked it. I liked it, but you know, Rogue two's agent is not exactly getting a lot of traction in Hollywood. But a rogue planet is a planet that's not orbiting a star. And you said earlier, and you're right that every planet feels the gravity from every star in the galaxy, but you have to look at its motion, like the motion of the Earth is that we are orbiting our star. We're moving around our star. But if we were a rogue planet, then our primary motion would just be around the center of the galaxy. Would be the same category as the stars, like our star orbits the center of the galaxy. It's a planet that's not sort of trapped by the gravitational well or pool of a star. Yeah, we liked to in goo a Solar System as an object because it's gravitationally bound that the dominant gravitational force on every object in the Solar System is the Sun. So it's like the Sun has its own little neighborhood in which it's gravity is more powerful than any other gravity. Or I guess maybe not not just that it's more powerful, but it's powerful enough to to sort of trap things in its vicinity. Yeah, it's a stable to let it go exactly. But you know, the galaxy is big, and there are a lot of stars, but they're not that many, and so there's a lot of room out there between stars. Remember, we're you know, light years away from the nearest star, which makes a huge amount of space for stuff to be floating between the stars. Oh, I see, So there's a lot of room for you to be out there without falling into the you know, the trap of the gravitational pool of a star. Yeah, if you mapped the Milky Way onto Earth, for example, you know, you have like one house here in Los Angeles and another house like in Kansas, and another house like in New York City, and there'll be a lot of room between those that you could rogue around it. Yeah, you can have a rogue cabin in the woods and never have to get close to anybody. And I guess more importantly, you could be so far away from my house and your house in Kansas, Dad, you wouldn't feel the need to sort of go visit. Yeah, and you could largely ignore them. You know, those stars would just be other slightly more bright stars in the sky, and you wouldn't feel their gravitational pull strongly enough to get sucked into one of them. All right, So then what's the definition then that it's it's a planet, meaning like a ball of stuff? Is that what it means? What is exactly a planet? Yeah? Well that's where it gets tricky, right. Um. These are either things that were formed in other solar systems and then ejected, or you could also think about stars that never sort of got started, like failed stars. You know what if a star never sort of turns on because it's not big enough to burn, is that a rogue planet or is that a failed star? Is a heated debate in astronomy, But both of those things are out there well in a way sort of Jube, isn't Jupiter also kind of a failed star? Like it could have been a star but it wasn't. Yeah, And if Jupiter had formed far enough away from the Sun on its own, if it was like the center of its own little gravitational neighborhood, we would call it a sub brown dwarf star. But because it formed around our star, we call it a planet. And so there's a lot of energy spent in astronomy arguing about these names and definitions. And wait, you're saying that if Jupiter wasn't in our solar system, if it was out there, it would be considered a star even though it's not burning. Yeah, there's a whole category of stars called brown dwarfs and sub brown dwarfs that are just not big enough to ignite fusion and to burn and to glow. But why still call them a star if they're not ignited? I'm burning, see what I mean. People have strong feelings about this, like you do. Apparently in your mind you think, you think, if it's got to be burning to be a star, right, Well, other people think, oh know, it's a failed star. That's a kind of star, all right, So that's kind of the definition. It's a ball of stuff, or maybe the definition is kind of fuzzy, but generally speaking, a rogue planet is a ball of stuff. It could be gas. Could be rock too, right, rocks or gas or you know, it's compressed matter kind of um just to make it different than a cloud. And it's floating out there in space, not in the orbit of a star. Whatever that could mean. That's right, it's a it's a dense blob of stuff. Primarily orbiting the center of the galaxy instead of orbiting another star. All right, let's get into how we can see them even though it's dark out during space and how many there are out there in the universe. But first let's take a quick break. All right, I know there are floating planets out there in the universe in our galaxy that don't have a star. They're called road planets, and there might be a lot of them. So first of all, I guess, how do we even see them if it's they're not burning bright and they're not near a star for them to shine, Um, how do we know they're there? It's tricky, right, These are dark objects. They are not shining, they're not emitting light, and as you say, they're not close enough to any star to reflect light like like exoplanets are. So it's not easy to spot them, which is why for a long time we didn't even know that they existed. Um, but there are two ways to see them. One is you get really lucky, and one is close enough that we can see them in the infrared. Remember, these things are not burning, so they're not shining visible light, but they still have some heat to them and everything in the universe that has a temperature also radiates some energy, usually in the infrared, and so sort of glowing in the infrared. And we have infrared telescopes, I see, because we I think we're used to thinking of like asteroids and things out there in spaces being cold, but you could have, for example, like the Earth is kind of warm by itself. The Earth is kind of warm. And even if we were ten or fifty kelvin. And I want to give props to the person out there who wrote in to remind me that it's not degrees kelvin, it's just kelvin. But even if we were just ten or fifty kelvin, we would still radiate. Everything that's above absolute zero radiates some energy. It's called black body radiation. Oh, I see. It sort of shines in the infrared. Yeah. And there's a telescope called the Wise telescope w I S E, which is really good at seeing this stuff, and it's really good in the infrared. And so if it's close enough that you can spot them directly with the Wise telescope, but it has to be pretty close. So like if our son suddenly went out and there was no more light in our solar system, you could still maybe see the Earth and all the other planets. Yeah, you could, precisely. And we do this to study other solar systems. We look at them in the visible light and we also look at them in the infrared to try to get a glimpse for like, what is the stuff out there that's not blowing. It's still there, it's giving off different kinds of radiation. So we have lots of different ways of looking at the sky. The infrared, X ray, radio, These are all just different kinds of light though. They're all just different parts of the electromagnetic spectrum. But different things out there glow in different parts of these spectrums. So the most direct way is to look for them in the infrared. But they have to be really close by, Oh I see, because otherwise it would be too faint to see them. Yeah, Because these things are small and pretty faint, and so they're pretty hard to spot. The best way to see these things is to look for a little star eclipse. What well, if you have a big dark object somewhere out there in the universe and it passes between you and a star, then what happens It blocks the light from that star momentarily like a one time eclipse. Yes, like a one time eclipse, one time ever eclipse, one time ever. Yeah. And so you can see these things if you very carefully watch all the stars in the sky and wait for a blip. But there's something really fascinating because you might expect that, like a star eclipse would dim the star, that it would go out for a minute and then come back, right, that's you'd expect, But this is really weird. Gravitational effect. If the rogue planet or whatever it is alien ship is big enough, then it has a gravitational lensing effect. It acts like a big lens in space. Because remember gravity is the bending of space. So gravity can change the direction of light. We'll just block the light, they'll bend the light. I mean that sort of happens here on Earth too when there's an eclipse, right, doesn't the light sort of go around the Moon when it's blocking the sign a little bit? It does a little bit. Yeah, And in this case it can actually enhance the strength of that star because it acts like a lens. It gathers more light and it focuses it all on the Earth. So what actually happens when you get a micro lensing event they call it, is that the star gets brighter, not just a darker or like darker and lighter. Yeah, it actually gets brighter. It gets enhanced, right, it gets amplified by this micro lensing, and so the very center of it is blocked out. But you're gathering light from nearby and focusing it onto the earth. You actually get more of the starlight when it goes by. It's an eclipse that makes it the start look brighter. Yeah, recisely. It's really fun. And the telescope to see these things has a really awesome name. It's called the OGLE telescope. I thought I thought it was already too much to have a wise telescope. W I s e this one. I want to look at things called the OGLE if you want to sit on the couch and ogle the universe, and you do it using the optical Gravitational Lensing Experiment OGL. Wow, you guys probably pop some champagne when you came up with that name. So those are the two ways you can see him. You can see them either through micro lensing or anti eclipses or directly through the infrared. And so what do we know about them? Do we know are they sort of round like our planets necessarily, or do they look like giant asteroids or what do we expect them to look like? Yeah, we expect that they're mostly round because anything that's big enough gravity will make it round. You know, gravity is powerful, and if you've got a bit that's sticking out, eventually it's going to roll down. And so you have something that's big enough to have strong gravity, it's going to get around. Oh, I see, And you expect these to be big, right, I guess if you're If you're calling them planets, there's a certain size associated with that name, isn't there? Like Pluto got demoted because it wasn't big enough. Yeah, But the really amazing part is that probably there's a whole spectrum of sizes, from like things bigger than Jupiter down to Earth size things down to just rocks, and the number is probably inversely proportional to the size. So there are a certain number of Jupiter sized ones, and they're probably more Earth sized ones, and then probably like a xillion times more just box out there. But at some point they're just called rocks. You wouldn't call them planets, right, At some point they're called planets and then dwarf planets, and then yeah, just comets or rocks or dust. Right, and you know, some of these things have come to our solar system. Remember Omama and the comment that came through UM in December. These are just rocks from other solar system that flew through our Solar system. Wow, there are Jupiter size planets out there, just floating in space, not being bound to any star, just doing their own thing. And that was the question when people first thought about this. They thought, are they out there? Let's go look for them, and so they started using these two approaches, and what they found sort of boggled the mind. Right, they found more than they expected. Yeah, they found that there's something like around one Jupiter sized rogue planet for every star in the Milky Way. So there's hundreds of millions of these Jupiter size rogue planets out there. Yeah, more like a hundred billion, yeah, because it's not about a hundred billion stars in the Milky Way. And a few years ago there was a really exciting result. Some people said that there might be like two to four Jupiter size rogue planets out there for every single star, so like hundreds of billions, and everybody was like reacted just the way you did, like what And then another experiment did some measurements and they came back to everybody, calm down. It looks like there's probably just about one jupiter size road. And I was like, that's still crazy. I mean, I was thinking like there might be ten in the whole galaxy. Turns out there's billions and billions of these things, and those are the Jupiter sized ones. The milky ways litter with these. Yeah, they're everywhere, and if as you go down the mass scale right like Earth size planets, there might be ten or even a hundred times as many. Wow, it's just traffic out there. It's pretty messages stuff. Nobody's cleaned up, right. We formed all these solar systems and that all the leftover base are just still out there. But you know, it gets more and more uncertain. As the size of the object we're talking about gets smaller, it's harder to see, and so we've seen fewer of them, so we're making more of an extrapolation with more uncertainty. We're in early days of understanding this, and in five, ten, fifty years we'll have a much better handle on it. But right now it's pretty uncertain. Are they going to keep on floating out there? Or will will all of these planets eventually kind of fall into a star. Think about what happens when a big Jupiter's eye planet approaches a star. It's not that easy to fall into orbit. Remember, orbit requires being in the right location, having the right direction, and the right velocity. Much more likely is that you come into a solar system and you just sort of like mess it up. Yeah, you perturb the gravitational, the nice cozy gravitational orbits of everybody that's been there for billions of years, and you make more rogue planets like you come in and you bust up a family. If a Jupiter sized planet came into our solar system, we would probably lose a planet or two. Well, I hope it's not Earth. They can take Pluto, Neptune. You know, we don't even we don't even care about those. Wow, they haven't even arrived yet. And you're and you're already at the negotiating table offering up our neighbors. What has urine has done for me lately? Oh? Come on, it's comic fodder. Urine is really I would give away Neptune first, I see it's less funny. I see you need you want you want to planet around you can make fun of it. Yeah, exactly, some some planet has to be the butt of all of our jokes. So okay, So it's not likely because they're if they're already floating out there, you know, careening through space, it's unlikely for them to stop at any particular start. They'll just kind of bounce around from solar system to solar system. It is possible, it's possible for our start to capture a new planet, and people wonder about the history of our Solar system, you know, like some of our planets have weird orbits. Is it possible they were captured? But if you just shoot a planet at a star, most of the trajectories will lead to it just being like whipped around and shot out into space and probably losing some of its planets. I guess. Then that gets us to the question of how these planets even formed. If they are not in a solar system, and they were, probably they can be captured by a solar sism. Where did they even come from? So let's tackle that question. But first let's take a quick break, all right, So where do rogue planets come from. Is there like a rogue planet factory somewhere? Is there a rogue nation of planets where all of these planets go rogue from their rogue nation. Well, it depends on how you define a rogue planet. There is a big population of them that were probably formed around a star, just like Earth and Jupiter and all of our planets. They were part of some big cloud out of gas and dust and rocks which coalesced to form a star and planets. But remember that's not like organized. Nobody planned our Solar system, and so in the early days of our Solar system, stuff was pretty chaotic. It's not like everybody had cleared it up and say, everybody in this lane become Earth and everybody over here. You had stuff sort of bouncing around more. It was more disorganized, and so stuff got ejected. So some planets that were formed in the early days of our Solar system probably got ejected are now out there and planets we have a lost brother out there or sister. Yeah, we almost certainly do. And it's almost certainly almost certainly we um. It's a fun question to ask, like what fraction of planets end up in stable orbits and what fraction get ejected? Um, And you know we're looking at our Solar system billions of years in. It's basically after everything has settled down, you know, in our Solar system, people think, for example, like Saturn and Jupiter might have once had different orbits that might have been in a different order because we had more things. Yeah, and that there was a third planet, another icy giant, which got ejected from the Solar system. Like you look at the organization of our Solar system for clues, and you're like, this looks weird. You know, would make more sense if this crazy thing happened. And that's how we ended up with this configuration of our planets. Oh. Interesting, that's right, because the Solar System didn't always look like the Solar System. No. And remember Earth had a massive collision with like a planet sized object which led to the formation of the Moon. Where did that thing come from? Well, probably our Solar system and so and now it's been obliterated. Okay. So so that's one way you can create a rogue planet out there in spaces. You it's born in a Solar System along with other planets, but then the other planets sort of get together and and kind of vote, vote that planet out. That's right, planet survivor. But you know, from that planets point of view, they're probably like, I never wanted to be in a solar system anyway. It's so much more exciting out here in the backwoods. I see much cooler out here. It is much cooler out there. Um. And it could also be, as we talked about earlier, that something comes by and perturbs and nice stable solar system, like a black hole comes near a solar system and perturbs it and sucks out some of the planets, or even just you know, another passing rogue planet. So solar systems are not that stable. So so those are rogue orphan planets I guess you could call um. Then you can also have like true road planets or like uh, independently formed road planets, feral planets, maybe we can say native planets. These are the ones that you were saying don't really count as a star, and they're called sub brown dwarf stars, and they're just clumps of matter that started to form together but didn't get enough to form enough gravitational pressure that you would get hydrogen fusion at the core of it, and so you never start to burn, because you could just have dust out there and gas and just have it. If there's nothing around it, it'll just come together as a clump. It will come together as a clump. Eventually gravity wins. Right. Gravity is so weak but so patient, and it just pulls this stuff together whatever you started with. And you know, you might wonder like how does that start? And that's a whole other fascinating topic. People think that these clouds of gas and dust and maybe like a supernova shock wave passes through it and that triggers the coalescing. Anyway, we'll talk about that in another episode. But whatever you got around you forms into a blob and if it's not bright enough to burn into a star, then it becomes to tonight to start fusion. Right, that's what you yeah, Because you know, if you just have a rock out there, it's not enough to start fusion. You need enough mass that the gravity sort of takes over and you start that star and then it's basically a sub brown dwarf star. Man, I'm just gonna pass judgment right now, Daniel. I think I don't think they should be called stars, alright, Just climbing a sub brown dwarves or something. So would you call them a rogue planet then? Yeah? Right? Independent? An independent planet or yeah, why not? Is there an argument against calling them a road planet? Well, some people think that, you know, a planet is something that formed around a star, and so that a rogue planet. I think the generally acceptable term is that a rogue planet something was around a star and then got lost. It went rogue. You can't you can't be born rogue in astronomy, apparently, I see if by planet you mean something that forms around a star, then technically I think that doesn't form with it around a star is not a planet. But this is all semantics, but it's just what people decided to call this thing, so they can have words that they communicate with and all mean the same thing. Or maybe they just like arguing about this stuff at meetings. That's probably true also, or maybe if what do you mean by star is just like celestial objects, um, then this could be sort of a non shining star. Yeah, and these things sort of go the same way as the rogue planets. That is, when it comes to stars. We know more about bigger stars because they burn bright and we can see them. It's hard to spot brown dwarfs and sub brown dwarfs because they don't shine like stars. We think that the number of these things grows very quickly though, as you dial down the mass of the object from bright star to sub brown dwarf to just dark little blob. So there's a lot more sub brown dwarfs out there than there are burning stars. There are more failed stars and stars. Is that what you're saying? Big surprise, right? There are more waiters than celebrities in Hollywood. Wow. The analogies just keep keep on rewarding us here. It turns out what we've learned here in Los Angeles does apply to the rest of the universe. In this one case, l A is the center of the universe. Obviously, it has taught us something about template is a template for the rest of the universe. That is terrifying. That is terrifying, alright, cool, So it's pretty interesting to know, to understand, to to have a sense that there are giant planets out there floating in space without a home. You know, they're just cruising through space like a like a spaceship. I guess, yeah, And you have to wonder, like, what would it be like to stand on the surface of that planet in perpetual night. You have no seasons, you right, you could do a lot of great astronomy, right because you have no sun to interfere with your telescopes. You could have a walk around that planet, go all the way around, and you would only see the night sky with stars in it. Yeah, but you could stay up all night long, every night. You would never get a sunburn's right, that industry, that industry would just not take off. Good for astronomers, bad for practicing gamble. Yeah, and also makers a swimsuits, probably because you know it'd be pretty cold. Right. We rely on our Sun not just for sunlight but also for the warmth, and it provides something like point nine seven percent of the energy on the surface of the Earth comes directly from the Sun. Really, but aren't there planets in our Solar system that are like super hot by themselves or is it all also from the Sun? There are like Venus is super hot, but all that energy comes from the Sun. And the reason it's super hot is that has these thick clouds that trap that energy. So all the surface energy from all the on all the planets in our Solar system is almost all from the Sun. But that's from on the surface, if you wanted to live on the surface and have a view of the night sky. But technically, could you in one of these road planets, could you like evolve life inside of it where where it is warm? You might because, as you say, the core of our planet is warm, and that's not from the Sun, that's from the gravitational pressure. Right, the Earth is also being squeezed and melt the rock, and from the radioactive decays that are happening inside that rock that radiates a little bit of energy. And so there is you know, there are hot spots underground. And so if you're on one of these rogue planets safe for example, the Earth went rogue, right, what would happen? Well, their ocean good? Not good? Right? You throw away all your sunscreen, Sorry about that, and the the oceans would freeze and the atmosphere would like turn to snow and just like accumulate on the surface of the Earth, which would be crazy. But if you go down deep enough, they would still be warmth, and so there might be enough energy sort of bubbling up through the crust to keep like a layer of water melted. Oh. Interesting, you could have like underground oceans. Yeah, you could have underground oceans that the Earth would be covered in layer of ice, but a mile or maybe two miles down there could still be water and it might be warm enough to sustain life. So you would throw your sunscreen, but not your swimsuit. Try to take your swimsuit or maybe your wet suit, because I don't think it's going to be very warm. But you could find like you know, cracks in the Earth's mantle underground where there's geothermal energy, and there are there is life the very bottom of the ocean, clustered around these thermal vents. Yeah, and they don't have any sunlight that you just live off of the hot water from these events. They've been planning for this for a long time. Yeah, they're ready for They're ready for Earth, Bill Rode. They're the rogue life right there, ready to take over when Earth goes rogue. There are the waiting waiting to rise up. But I think what I what I'm saying is that that that could happen in one of these rogue planets out there. I mean, there could be like a giant floating Jupiter out there in space. It's actually like a spaceship full of life under the surface. Yeah, and it doesn't have to be that life evolves on a planet and then it goes rogue. I think you're saying, like, could life evolve on a planet when it's a rogue And I think the answer is yeah. You could have a good water on a rogue planet and life could evolve, and it could evolve under like a mile of ice and never see the sky. Right, it might not even be aware that the universe is larger than its ocean. It would be like rogue life. And you have to wonder, like, what kind of technology could you evolve? Like, could you become intelligent? Could you evolve technology? Could you drill out of the ice and then discover that? Imagine what that would be like to be that kind of I want to read a science fiction novel about life that evolves on a rogue planet and develops the technology, drills as of the ice, and then discovers Oh my gosh, the university is so much bigger than we ever imagined. What a moment. Right, There's a story that you and I were talking earlier about. The writer thought Chiang, he has a story I don't know if you read it, called The Tower of Babel where that's kind of the plot where they drill through the ceiling of heaven. Oh my gosh, I want to read that story. That sounds awesome. Yeah. Alright, So that that's kind of possible, is that there are and and there are so many of these road planets out there that it's it probably is maybe possible that there is life and the life started in one of these road planets. Yeah, it's very exciting for the possibility of alien life, which you know, I'm a fan of. You know, recently we've learned that there are a huge number of planets around other stars. That was a big moment just in astronomy in general, but also for us who promote alien life, to realize that there are other places for life in the universe around other stars. That was exciting. Now we're learning that that's a tiny fraction of all the planets out there, and that there's an enormous number of these dark rogue planets, and I think it's more challenging for life to form on a rogue planet, but hey, you've got more opportunities also, right, there's a there's like a hundred billion rogue planets the size of Jupiter. Yeah, and maybe tend to a hundred times as many Earth sized planets out there, and just in our solar systems, I mean just in our galaxy that would be getting kind of crowded. Just in our galaxy, I mean, I mean the galaxy. There's hundreds and hundreds of billions of these and and maybe there are hundreds of billions of galaxies. So who knows, right there could be a rogue life form out there. My money is that there is. I mean, it just seems so much more likely. It seems so impossible to imagine that nowhere out there, in any of these planets has life begun. There's so many opportunities and so many ways for life to happen we haven't even imagined. I would definitely put my money on there being rogue alien life. Can you imagine them bursting out of their shell and be like WHOA what is this? Even crazier though, is that like one of these rogue planets could pass by our solar system, you know, within a few au you know, just outside the edge of Pluto, and we wouldn't even see it, and they might not even see us, And so we could be like there could be like cosmic neighbors and zooming by and we're not even paying attention. And maybe, just maybe this happened a few billion years ago, and maybe, just maybe an asteroid hit that road planet and ejected a piece of rock with life that then landed. I'm taking it too far, No, I like that. There are a lot It's totally possible. It's possible for life to have originated somewhere else and then come to Earth. All right, Well, that's pretty interesting to know. It just sort of makes you look at space and the night sky differently. And in all those places where you only see blackness, there could be planets out there, floating and possibly with life. Yeah, and this life might not be looking back at you. It might be hidden under two miles of ice, looking up at the inside of its ocean and wondering what l is out there? Right, that's no interest in being famous like a star, only because they don't even know it's possible. Once they get a taste of it. Though, Once stay discovered television, it's all over. Who doesn't want to be a star? All right, Well, we hope you enjoyed that little tour into the blackness of space and what could be out there. Waiting for us to discover and as usual, you are in no danger as you sit on your couch or sit in the seat of your car and listen to us helping you explore the universe. All right, We hope you enjoyed that. See you next time. Before you still have a question after listening to all these explanations, please drop us a line. We'd love to hear from you. You can find us on Facebook, Twitter, and Instagram at Daniel and Jorge That's one word, or email us at Feedback at Daniel and Jorge dot com. Thanks for listening and remember that Daniel and Jorge, Hey, Explain the Universe is a production of I Heart Radio. From more podcast from my Heart Radio visit the i heart Radio app, Apple Podcasts, or wherever you listen to your favorite shows. Yeah