Audioburst Search

The Search for New Planets, Sun Blobs andHotJupitersw/ Sara Seager

Automatic TRANSCRIPT

Hey folks. Do you like podcasts like the one you're listening to right now or like other podcasts on the ear. Wolf Network and do you like putting things on your body or putting liquids in containers. Well then check out. PUD SWAG DOT COM for all the podcast swag you could dream of it's right there in the name pod. SWAG DOT COM for podcast swag to find it and get yourself self some sweet year. Wolf merch go to pod SWAG DOT com the context hello welcome to factually Adam Khan over and you know these forget but we live on a huge watery magnetic rock that is to say a planet. That's what the planet is and this rock circles as slow motion nuclear explosion and since there others La- motion nuclear explosions out there floating around in the void. It's logical to conclude that there are other water. MAG balls circling them right other planets just like ours. That's an exciting thought because planets are wear life grow so if they're alien planets. Maybe there's alien life out there. We can talk to or destroy. You know maybe we're the bad hey guys in the movie. Hell maybe we'll eat them. Maybe we'll just be giant alien farms alien ant farm good band underrated but just because it seems likely or intuitive that other stars have planets planets that doesn't necessarily mean it's true right science as always requires evidence to establish anything and if you go back to the early nineteen nineties even and we actually didn't have any evidence at all that other planets existed humans had advanced to the point where we've created. Microsoft Excel and Madonna's sex book but we still had zero proof that there are any planets outside the solar system let alone any that might support life within the astronomy community the search for EXO planets as planets. It's outside. The solar system are called was considered a little Kooky. It was a weird topic and it was even treated with some suspicion because there'd been decades of claims that exo plants have been discovered but all those claims have been proven wrong which made the whole field seem a little scammy. You know Kinda like people who say they've discovered cold fusion or who describe had themselves as influencers right you just have trouble trusting them but in recent years all of that has changed there has been nothing short of an exoplanet revolution Aleutian in astronomy. The first breakthrough happened in Nineteen ninety-two astronomers at the Era Cbo Observatory in Puerto Rico actually discovered to actual planets. That's about twenty three hundred light years away in the Constellation Virgo but importantly this planetary system looked nothing like ours. These planets were four times the size of earth with orbits the only ninety eight and sixty five days and the system is tiny the whole thing could fit inside the orbit of mercury but it was a start three years later in nineteen ninety-five. I five there is another huge step forward. Scientists discovered a planet circling a star like our own Sun in the Pegasus Constellation. It was a gas giant about half the massive Asif Jupiter which circled its star once every four days not very earth-like but still after that point that floodgates open and Jupiter like planets planets were discovered on a monthly or sometimes even weekly basis from then on by two thousand two. We've confirmed almost a hundred EXO planets but look I know I know who cares about Jupiter sized sized planets. Those big gase guys crappy candidates to find life to find live. We would need to find earth size planets but earth size planets are very very difficult to find from the surface of earth itself to find smaller planets. You need to go into space and in two thousand nine. NASA launched the Kepler mission to do just that part of couples job is to find find out how many planets exist in the habitable zone where life is possible in their solar systems and it used what's called the transit method of EXO planet discovery to do that now. We're GONNA talk about the transit transit method a lot later in this episode but you need to know is that Kepler helped create a gold rush of planetary discovery unlike anything else in scientific history think about out in one thousand nine hundred we had no proof that there was a single planet outside of our solar system and now over four thousand exo planets have been identified more on the way and we are able interesting that there are up to ten billion habitable planets in our Galaxy Day by day. We are inching closer to finding another earth like planet and defining the telltale signs of life out there in the universe to finally find out that we are not alone well our guest. Today is a leading figure in this effort to to find another earth. She's an astrophysicist and a planetary scientist at mit and a macarthur fellow. Please welcome Sara Seager Sarah. Thank you so much for being on the show great to be here him so you search for EXO planets at Mit. Tell me about how that is done like what is what does that look like on a day to day well. The funny thing is finding planets like a lot of jobs. We sit in from the computer a lot. We have a lot of meetings the differences though at the end of the day we find lots and lots of what we call planet candidates and the way we do this is we actually have a very fancy very expensive space satellite. It's called tests like the girl's name transiting exoplanet survey satellite and tests is essentially like four glorified telephoto lenses if you will all attached to a platform and it looks out lots and lots of stars over very wide field of the sky and that data comes down to Earth through the deep space network and we analyze that data looking for planets and so what sort of analysis of the data shows you that a planet is there because my understanding is. You're not actually able to see these optically right. You're not like literally seeing a sphere against a black background and going Oh. I think I see some clouds and stuff. So so what are you what are you looking for. It's really a lot of detailed detailed work. What we're looking for is we're looking at. We're looking for planets. Whose orbits are specially aligned? They're called transiting planets and as seen from our telescope hope they happen to be fortuitously line so that the planet goes in front of the Star as seen from the telescope and what that amounts to is just a tiny tiny tiny drop in brightness uh-huh with a very characteristic shape so we're monitoring all these stars like tens of thousands hundreds of thousands of stars at a time and our computer literally punks a little circle down over each star and counts up how bright that stars and it does that over and over again as a function of time and then the computers looking for that little tiny drop in brightness that repeats each time the planet goes in front of the star does so cool so it's just a it's just looking for a little periodic flicker exactly it's a periodic flicker and it's funny but this field is really quite mature. Now I mean it seems crazy right to just say hey this type of planet finding it's it's just mainstream routine and I could even train like if you wanted to and you were here I would invite you to one of our planet finding sessions because you know our computers do all the hard work but at the end of the day we go from tens of thousands of these so-called light curves down to like fifty that we have to sort through as humans and we have a team of experts and we all sit around the table in the screens twice a week for a couple of hours. Those are our planet vetting sessions and we sort through them and yeah I wouldn't if you around here. It actually invite you due to see how that operates. I'm a hundred percent going to take you up on that. That sounds amazing all right that'd be so fun and so once we find these so-called planet candidates we release them to the community and they're publicly available if you know where to get them to get on the Internet it's on an archive called mask and they they host pretty much all astronomy public data and you'd go on there and you could download the light curves and we also have coordinated follow-up team because these little flickers of light as you called them. There's a number of other things that could be causing them. Specifically Binary Stars to stars that happened to each other and eclipsing each other which is Louis Louis legalist arrangement for stars like I love Yeah. I love thinking about it but okay so you know some of these the binary okay well. One person's trash is another person's person's treasure. NFL for us the binary stars we just don't want them and so we have a team of follow up observers and they're somewhat self organized to sort through what these these little dips and later are they genuine planets or are they false positives and so there's they're binary star people out there. Who If you find it. It's a false positive. They're you're like. Oh boy a new binary star for me Binary Star Man. That's a hate there binary. They're all the people out there. The binary stars variable stars. Some stars just vary in brightness seemingly randomly. There's people who like that. There's very special types of variable stars like they have names like Delta Kuti. They're named after their prototype star and people love specializing unlike individual types of variable stars so there's all kinds of interest so this is a very like crowdsourcing is not the right word but this is a real group effort for it to like sort through all this data I with computers and then with humans pouring over it to find the planets are are we limited so I'm interested when you you say the transient transient planet so they have to pass in front of the Star from our perspective in order for us to detect does that mean we're only able to detect a very area that must be a small subset of the number of it is plans that are out there so we said we limited to a really small subset of what we're able to see for now now we are. I mean there's a lot of other techniques of planets this particular one transiting planets. It's actually just the most mature and in terms of the detectors and the technology. It's just just the easiest way to find planets right now. That's why it's right now the main game in town but if we had this conversation you know ten years ago or ten years from now we might be talking about a different planet finding technique. I Love I love charting the way that science changes in that way that the techniques change and the discoveries that we make as a result alter the techniques change. Where do you have. Are there techniques that you foresee coming in the future of the that'll become mature that allows them in different ways. Yes there are there's. There's a couple of them. I can describe both if you honor pick one but we'll see you so the transiting planets definitely it's limited and just you know it's really just the first part of a much longer journey in discovery. Would I really like my favorite method. That's still to mature are is called direct imaging and that doesn't mean we're going to get a picture like the beautiful apollo images of earth it means that we will see the planet and its own reflected light but to do that we have to be able to block out the starlight to see the planet directly so imagine like putting your hand up to the late or your hand up to the sun and blocking out we have to block out the starlight and astronomers already do this for a special kind of really weird type of planet but there's some very big very hot very young planets out there and they shine from their own thermal energy heat and we can block out the starlight and we can see those planets typically quite far from the star. They're not like really anything that we call that you know we're familiar with from our own solar system but nonetheless the technique works. They're the only problem is we have to do way better to find planets like those in our solar the system particularly like Earth's like we'd have to make the technique. Maybe I WANNA say one hundred thousand times better so that's the big number I mean imagine trying to make anything you do one hundred times better yeah uh my my goal for my own life as a comedian is to make you know maybe do things twice as good three times good. I think that'd be the maximum I could hope to achieve but doing the same thing a hundred thousand times better as wild but that's I mean that happens in science right. I mean our our ability to. I don't know look at data transmission and you know you know. Pack Technology and stuff like that is is orders of magnitude youtube better than it was a hundred years ago. It's not it's not wild to think that that could happen right well. We're planning for it to happen. Oh that's what I that's what I it. That's that's amazing so let me describe it a little more to because there's different ways to block out starlight but one way is with a giant specially shaped screen and we call it star shade and Star Shane rationing and you've got a great these numbers yeah to listen to these numbers but it would be tens of meters in diameter so imagine if the star she's thirty meters in diameter. That's somewhat close to one hundred feet. That's wow I mean. One hundred feet wide and this star shade would have its own spacecraft craft and it would fly in outer space with a telescope. They're separated from each other by vast distance of tens of thousands of kilometers well well and this star sheet has a very special shape. It's shaped like a flower and it would block the starlight completely so that only planet would enter the telescope. That's what a what a beautiful image just like astonished picturing what that would look like How is it able to separate the the light from the star versus the light from the plan a knuckle quite clear on that mechanism well it just it's actually I'm GONNA explain the complication from it but the concept itself is really quite straightforward because it would be like you having let's say a dinner plate like a circular kind of object putting it in front of the Senate and putting it in front of the Suns at arm's length it would just block out the light so to like the overall concept is literally just blocking the major complication is this though it turns out if you block out a point source of light like a pinprick of light guess what you actually don't end up blocking out because light can act like a wave and instead of blocking it out the light. Benz around the edges of if you had a giant circular screen and you get ripples just like if you throw yeah just like if you throw a pebble in a pond ripples but these are light ripples not waterway ripples so what the star shade has this like a very clever for solution is it's an incredibly special shape so that starlight that you're blocking out it's still diffraction sill bends around the edges but it cancels itself vowed in a very special way so that the image is incredibly dark that would be like throwing a pebble in a pond and instead of getting ripples the pond would be perfectly smooth well the waves all the waves would be pushed to the outer edges so you're you're controlling rolling the shape of the pebble such that the waves that it generates cancel themselves out perfectly so it ends up going into the pond with no ripple. That's a really interesting way to look at it yeah. We'll the ripples would be configured. Somewhere else that is that is so so so incredibly credibly cool all right I'm you know I it for you to be doing this in your daily life and and then to talk to someone like me who's thinking about it for the first time and having my mind blown by must be a little. I'm glad you well. It's great that you're so induced about it but this idea was first conceived in the nineteen sixties really gives an idea kind of on paper and mathematically was conceived by a personal lyman Spitzer who is also one of the literally the a father of the Hubble Space Telescope and it wasn't like build a bull or anything at the time nor was it billable each decade when people revisited it and in two thousand some fifteen I got to lead a team of people in our job was to either bring star shade to life showing the world that it's possible or to show the world it's impossible and it's an idea that should be kind of shelf forever so fortunately we showed it was possible and we continue to work on it. Today are there are there plans to actually launch it and and included well. That's why that's why I said before. We're doing the easier things I an easier usually means cheaper so we the ideas out there. Were we're kind of competing to try to get selected but it's not a funded mission right now. It's moving forward developing technology so we hope it will be real someday but what you're eating with a lot of other ideas yes but you're working on it in order to make it real one day. You're in that you're in that. We're working on it. That's right. We're working on it to make it real one day and so if you do that you will. If we have that star shade we'll be able to see EXO. Planets not not see them directly but just observe their light directly yes. We'll be able to observe their directly. Which is why we creatively call it direct imaging and we'll be able to see solar system like planets around on the nearest sun like stars like we'll be able to see like another earth another? Jupiter another Venus may be things like that and those are the real goal yeah those the things that are hard to see now like seeing seeing earth size planet is specifically difficult as my understanding seen an earth sized planet around a Sun like star in an earth like orbit hasn't hasn't been done actually. It's still out of reach really that so because I know that you know as I talked about the intro. We've now seen many many exoplanets but we have not seen in sort of an earth twin in that way at all no no but we're starting to think we have a bunch of like call them cousins around. We're not sure exactly what they are but right now many of the potential earth cousins there around small stars much smaller and much redder than our sun again. We're kind of doing the things I but we have a phrase. We call it. You could probably think of something more funny and pet for astronomy about as funny as we can get. We call it. The race to the bottom got us. Were racing to like look at the smallest ours possible the smallest stars it's just easier to find planets around them because the signal is bigger like imagine the transiting. Anthony Planet going in front of the Star right in front of a small star it takes out a much bigger area than in front of a big star. So how do we when you're actually trying to learn about those planets. If all we're seeing right now is a flicker in front of us star or if you know in the future if we get star shade Goin Owen and again incredible name I love to say if we get star-shaped going and we're getting that direct light that still far from actually being able to to go like look and see. Oh yeah I'm seeing an atmosphere look. See some purple clouds or whatever how do we learn about the planets from this somewhat abstract sounding data yeah and the funny thing is that hundreds of people around the world work on that very question one way is that when the planet goes is in front of the Star it blocks out light in the ratio of the area of the planet to the area of the Star so if we know the area or the size of the star we can get the size of the planet similarly. There's another technique we could follow up with to get the mass of the planet and if you have the mass and the size you can get the density of the planet so you could no is this like really heavy like a rocky planet it or is it very kind of light like a giant exit plant like a giant planet like Jupiter so kind of we can tell approximately what the planet's made of if we can get a mass in assize so that's the first thing to do the second thing with these transiting planets and I'm not sure if this will blow your mind or not but when the planet goes in front of the Star I I want you to imagine the star light shining through the planet atmosphere just like shining a flashlight through fog some light might make it through in some light may not make it through right and so because the star lights shining through the atmosphere we can pick up what part of that is from the planet atmosphere and we're actually able to measure the very crudely but what is in some exoplanet atmospheres and dozens of exoplanet atmospheres have been observed that way yeah that does my mind and you have a great track record for blowing my mind over the of course of his episodes so far you're saying that based on the quality of the light in that little flicker you're able to detect because because it's some amount is being blocked by certain atmospheric qualities you know certain certain things in the atmosphere. You're able to tell what's in the atmosphere by what happens to the light passing around the planet. I I can actually see yeah. I can explain it a little more specifically. So first of all we can look at the star by itself and then we look at the star when the planets in front of us star and we can subtract those and then we're left left with the atmosphere but here's the thing if you ever look at a rainbow so everyone hopefully go has got to see a rainbow at some point the summer I got to see I saw even a double rainbow. Oh but you what you probably don't know is that if you look at a rainbow very very very closely you would actually see that some parts of the rainbow are missing like little tiny the colors little tiny strips of colors would be missing like a tiny bit of really dark ride and a little more of maybe light red and orange in fact is because of molecules in our atmosphere will in the sun's atmosphere and in our atmosphere they absorb radiation the molecule delay explain to my students is like the molecule kind of takes a bite out over the rainbow and they're all these lines called spectroscopy lines and people work hard to match up like a fingerprint if you will like each atom and molecule has a somewhat unique fingerprint of which colors it takes away and so effectively we look at this transit at different wavelengths wavelength or in different colors and we see those different differ from each other so there's so the atmosphere has a because of the elements that are in the atmosphere has like a fingerprint anger print that causes some light that goes through it to be do not travel all the way through exactly yeah exactly. You said it way better than yeah no I. I want to take that one step further though I want to get one step further to what it really is imagine now. We're looking at a color or wavelength where the atmosphere's transparent. There's there's no molecule or atom or anything. Absorbing at that particular wavelength then the planet is a certain size is just you know the size of what it is now imagine an adjacent wavelength or color where there's gases like molecules atoms that are absorbing incredibly strongly. The light is not making it through as you said and the planet actually appears a tiny tiny tiny bit bigger is that atmosphere is like adding another layer to the planet and so we're specifically looking for transits that are different sizes sizes at different wavelengths. Oh Wow okay. I follow yeah if you look at different wavelengths of light would the planet would appear different sizes because certain more of is getting blocked at different wavelengths exactly yes. That's what that's what it is actually wow that is so cool and also by the way I had no idea that happened with rainbows on earth that we're seeing in a way earth's fingerprint every time we look at a rainbow we're seeing its own spectral graphic fingerprints. You're seeing Earth's but mostly mostly what you're seeing in Earth's rainbow if you could do what I said was most of what you're seeing is. The sons actually so-called photos here. It's called photos here not an atmosphere but mostly what you're seeing is coming from the sun but yes you could you could actually see Earth's imprinted on that and what you you know we have these instruments. We call them spectra graphs and they split the sunlight up so much. It's like a rainbow spread out hugely over your detector and that's where you can really see those lines amazing so you can also get these. You can also get these little slides. We use them in the classroom awesome and you hold it up to the light and you can see what I'm talking about. How how so like you hold it up. What do you see like it's a little slide. That's what it's called a diffraction grating. It's sort of makes fake rainbow for you. So it creates a rainbow for you and you literally can see these little black lines where mostly things in the sun in our absorbing I see just demonstrate that affect demonstrate yeah just agenda straight yes that is so cool so so by using all these techniques weeks and by the way this is incredible that you're able to get all of this from again what seems like the tiniest amount of data just a little flicker in front of a in front of a star you're. You're you know we've been working at right. It sends incredible but we've been working on this for a long time in fact. I know this will sound like very arrogant but I actually invented that technique almost twenty years ago. Wow twenty years ago. People thought it was just never going to go anywhere. They thought that you know we can barely find planets. We don't even really know if they're real planets and when the first transiting transiting planet was found I actually wrote this paper and I worked super hard to get it out because it's a highly competitive field and people use that technique a couple of years later and saw the first gas yes in the first exoplanet atmosphere then and today it's become so standard it's standard in the field and there's dozens if not like over hundred people around the world or more working on this. I first of all first of all that is not arrogant at all for you to say. I'm so happy that you said it and I if that were me. I would be shouting from the rooftops because that's incredible bill so you're so you're saying that the technique that you invented was later used to fine the first gas plan X. Plants. Is that the case well. It's it was it was the technique was used to find the first atmosphere around on an excellent. What I have to ask what what does that feel like you know as a you know as a scientist but also as a person to have made a contribution that has really enlarged our understanding of the universe in like such a concrete way. I haven't really thought of it that way. That's off have to think about it. I mean there's several things I could say but one is of course I'm very proud of that secondly. Honestly there's a huge comfort. Just knowing that the laws of physics and chemistry not only only apply everywhere but they're reliable you can use them to you know say something and that that can really be reality. That's amazing to the third communists. You know we're always onto to the next thing you know. Ambitious people like there's never any rest like I'm sure it's the same with you do something that people think is great but now it's the next thing he's on the next thing certainly certainly the that's that's one hundred percent true and I'm always yeah. I'm I'm never able to to re you. You have to try to find those moments of pride in your work and okay that actually was there actually was really cool that that that happened but yeah. I relate to that feeling of you know. I've I've only gotten little glimpses. This is of it myself when often like working with computers or video games or things like that where I think I I come up with a theory about like oh I think I think it works this way and then and I I think this is how this system operates Let me come up with a theory and see if if if I'm right if I tested somewhere else when it does there's like a huge pleasure in knowing that you understood the laws and you were you were able to use them to make a valid inference but also the laws are like universal in whatever sphere working in there is a real comfort in that that must be an incredibly powerful feeling scientist it has it's very gratifying. Wow well. Let's let's talk about what everyone everyone wants to talk about. The most is again earth-like planets and finding life on planets because well for so to some extent that often seems like our goal like like that's certainly how the press reports on it is when you know whenever an extra planet makes the news it's when it is most similar to Earth or or more related to to life in some way first of all I want to know. Do you share that desire. Is that your goal as well or are you interested in in any old planet. I I definitely share the desire and make it my life school to find another earth like a true earth twin orbiting a sun like star and hopefully one that shows signs of life on it and so as as the so that's my main goal but as there's about their right as the kind of days and years and decades go by. I'm still doing my best to like make the foundation for it so that even if it can't I mean it sounds terrible. I shouldn't be saying as you know if it doesn't get to happen for me. I gotTa make sure it can happen yeah. I don't think that sounds terrible at all. I think that sounds absolutely correct like I mean the wh- what about it sounds terrible that it feels that it shouldn't be such self driven desire that like you know I I want to find it is that is that your concern or so so much that it's just like some really big on having concrete goals and realizing them right so it's sort of depressing if you can't reach sure goal. I think that's the way to see it. So when I started working on earth and earth twins around Sun like stars. I got to be involved with these big NASA concept projects precursors to the star state if you will but I was always the youngest person like I'm sure you had that as well. There's some point when you're like you look around. You're always the youngest. We're young is like thirty so yeah so so you're always the youngest person it's like. Oh this. I have so much time. This field will always happen. Things always go now. let's say twenty years later or more. I'm now I won't I don't think I'm one of the older older people but I'm one of the leaders say you know we went from that to that but then what happens twenty years from now than I roll off and then the other people roll on so instead of like finding that perfect or twin win with all the signs of life and water and all the other wonderful things now my goal is to get star. She launched even if it's a small version to find planets that are like earth that show water in the atmosphere water vapor which on a small rocky planet is signs of liquid water oceans needed for all life as we know it and hopefully won't even oxygen where we may not be one hundred percent certain so you'll be interviewing me or someone else download and we can't say oh yeah. We're definitely there. No we'll say hey. This is great. This is like the planet candidates I told you about. This is like a life potential. Oh but we need more work because once we can anchor it with like an amazing discovery that now people are going to want to do more than more things will fall and then the next generations can continue the search and why why do you feel that the search for an earth twin is like why why is that the goal for Goal Oh for you. Maybe that's an easy question. Maybe it's a hard one. I think it's a hard one. I mean oftentimes. It's hard to say why we're doing what we're doing. You know like you can't ask a child. Oh why did you learn to walk. I mean they just sometimes you're just driven on the inside for some reason one of the reasons. I think is so we do kind of want to know. Where did we come from you. Know why are we here and this is just more kind of concrete scientific way of trying to address that question like how did our earth come to be. Is that unique is is it rare or are there more like it out there. Do you feel that in your if you if you had to give it a probability of in your lifetime us us finding that earth twin. What would you give it. I do have a number. It's going to be funny but it's like eighty. Five percent eighty five percent yeah I did that makes me so happy because also I'm a little younger than you. I think so I think my number will be a little higher. Maybe this is the thing is that we know. Planets on its are incredibly common. It appears that allstars as far as we can tell seem to have planets except maybe some extreme really big hot stars yes and with the Kepler space telescope scope although we didn't reach down to the truth twin Kepler has shown that small rocky planets are also very very common and so. It's likely that they're out there we just I I feel I do believe that the I mean all the evidence points towards that small rocky planets are very common and that's why I believe that the nearest sun like stars ars have rocky planets just waiting to be found and then how far does that go to you know being an earth like planet the small rocky planet around a Sun like star. Does that fit earth twin for you or do you also want to see water. Do you also want to see green stuff. You know how many colors that exist on earth need to exist on this planet for us to say this. Is You know we've found what we're looking for. I think we definitely WANNA see water. We definitely WANNA on a planet that has liquid water which will see by seen water vapor. If we know it's a small rocky world think about it like Venus also rocky planet but Venus is like our sister planet but it's incredibly hostile to life so hot at the surface hot enough to melt lead yeah and and if we and maybe this is not even in your field because I think astro biology is something else but if we were to find that small rocky planet with water on it you know life just being a chemical reaction that exists exist under the right circumstances as I understand it. After we've gotten that far down the you know probability curve to finding all those elements. What are the chances that it such a planet could have life on it. You know we definitely don't we don't have a scientific answer to that. I would love to say that I I. I think if the ingredients are there. I like to think life will find a way to form but we're that's partly what we're we're trying to address. The funny thing is there's people here on earth who are trying to create artificial artificial life in the lab like they're literally just trying to start with basic ingredients and create a cell a living cell cornelis. Tell me well yeah. They always tell me you know we find signs of life elsewhere. That's fantastic because they'll know that their job is. Let's say easy right. Life can happen all the time but the other way round no no no. I need you to prove that you can figure out how to make life because if you can do that tells me that life should be everywhere because it's easy to get started right so based on that sort of assumption that I laid out which I I assume would be shared by you and these folks that that life is a chemical reaction that given the right substances in the right conditions life is going to sort of spontaneously form is is that correct. That's you're correct on must show. I share that assumption. Although I don't know if I'll biologists show that assumption got it but so there are folks out there who are saying all right. Let's try to get the conditions together and see if we can do it. Let's see if we can get some molecules replicating themselves elves with variations right That's man well you know after the show. I'll hit you up. Maybe you can connect me one but those folks is now. I want to talk to them too but I have so many more questions but we have take a quick break. We'll be right back with more Sara seager. Look let me ask you questions. Your calendar to empty are those big gaps in between your events staring staring a hole right in your face. Well meet the Scheduling Assistant that works twenty four seven behind the scenes to fill your calendar from the moment clients book with you. Acuity is there to automatically added. We send confirmations deliver text reminders and process payments. You never have to ask that dreaded question. What time works for you again. 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I just go to acuity scheduling dot com slash. Factually that's a cutie scheduling dot com slash. Factually I all right Sara so we've been talking about why we wanna find an earth like planet let's talk about what we you know how we go about finding one what we need to do in order to find one you said you were in your race to the bottom looking for you know the smallest stars stars in order to find those is that did I understand you're right that very small stars or where where we might find an earth twin or well that very small stars. I'd say we'd find an earth cousin so we might find a planet that could support life around Red Dwarf Star but it would be very different from what we have here on our planet. Let me explain clean not to you though please just for a moment I wanna take you on a virtual trip to a rocky planet around a small star a rocky planet in the so called Habitable Zone of that star so first of all the small stars they give out very little energy so for planet to be the right temperature for life. It has to be pretty close to the star. That's like the Fire Era Campfire. If it's a small fire you have to huddle pretty close to it to stay warm and that's what the had a weak zone means right that there's a distance from the star where you're going to get the right temperatures. You would need in order for water in life-form right. That's that's the habitable zone. Yes and they're like everything in science. There's a simple picture and then it's always more complicated than that. Of course you know what it's the greenhouse effect of the atmosphere that really controls the surface temperature like you're on our planet. We're worried about adding adding parts per million of carbon dioxide but imagine if these planets had way more carbon dioxide you know they'd be way hotter but anyway so we could go to this planet first of all the Star might be a bit bigger in the sky depending on the system sears. You know because you're closer so the star might be bigger. What's interesting about these planets because they're so close to the star. Do Tidal interactions just like our moon and the earth have reached tides on each other. You know we have the ocean tides because of these interactions over long periods of time. The planet gets into interesting configuration. It would rotate one time for every time its orbit's. That's like the Moon or moon is so called tidally he locked. It shows the same face earth at all times right. It's actually rotating one time for every time it orbits so the we this would mean if we could visit the planet is that one side of of the planet is always in daylight and the other side is always night. So which side would you go. Where would you go. Which side would you go to the the light side. I think so I could see stuff okay well. The astronomers would probably go to the dark side but for what it's worth fair enough honeymooners you'd want yeah and the honeymooners. I might go to where the sun is always setting. wow desire because the sun is always in the same spot in the sky depending on where you are on the planet surface. That's right the planets always in the same part of the sky at all times. Wow crazy this world is a little different also because the planet is so so close to the star by Kepler's third law planets closer to the star also or bit more quickly so when some of these so called earth cousins around small stars a year would only only be about ten days. Wow Yeah so every year would go by pretty quick. Although who knows maybe they'll celebrate centuries rather than but but how would you even mark mark a year going by because there are no days because the planet's not rotating yeah there are no days but don't forget it's orbiting and so the stars in the UH night sky they change over time just like here on earth. You know sometimes if you if you look out at night Orion we only see a Ryan around here here at in the wintertime actually so you know whenever I see a Ryan Setting. It's this giant constellation the western sky. I'm so happy because it means. Spring and summer is coming and then now in fall you start to see it and it's like oh great that means we're in for a cold one that means long cold winter is about to arrive so he had just like that. The stars would be different. That's the only way you can tell. I guess you'd have to go to the nightside to tell that yes so so the sun is stationary but meanwhile the stars are like whipping around basically because you're you're orbiting yeah. That's that's right. Yes that's right yeah going to this point. It sounds while it does. It sounds wild. It'd be cool to go on vacation. They're just for you know a difference but on the other hand it could be terrible planet to visit because most so these like nearly all of these red dwarf stars have flares giant bursts of energy that would hit the planet and 'cause you know huge UV index index. Like what kind of sunscreen would you bring it could you. Couldn't you know you know how we're addicted to our cellphones. The high energy particles from these flares. There's would knock out the electronics and your phone wouldn't work. Wow so these flares are pretty crazy and you know maybe it wouldn't be such a great place to visit after all the flares and these high energy particles would because mutations and cancer so we kind of go back and forth about these earth cousins you know do the planets even have atmospheres these flares and other activity from the star like blow the the atmosphere way. Could there be like there. Maybe it has to live on the dark side or under the surface to be protected from these flares. We're not really sure wow that's that is that is such a wild vision is is it possible for life to arise or water to exist and that kind of situation or is there like back to crazy of a temperature differential or anything like that well so people have been working on you know we always haven't we have an answer for almost any question so that's good news uh-huh and people have worked out that have worked out that if there's an atmosphere and as long as the atmosphere is let's say mark like Marzieh's atmosphere which is a pretty thin atmosphere than the energy will circulate circulate around the planet and it should have somewhat of an even temperature. Do you know our planet our planet. Venus rotates very slowly like it rotates it has like a few hundred day rotation period I want to say it's like two hundred and something so Venus has the same temperature all around because it's got this heavy atmosphere that moves energy around just like for for people who live somewhere where it's when you know it's still hot out now but winter is always come approaching. They GonNa Winter's Day. If you open your door to your house or your building than the hot hot air rushes out in the cold air rushes in so it's like that hot air wants to move around where it's cold so that probably wouldn't be your biggest problem is probably these flares on earth. We had on on earth this digressing a little boat an earth in the around. I WanNa see it was about eighteen fifty. We had a giant flare event and it has a name name. It's called the Carrington event after Carrington British astronomer. Who was studying the sunsetting sunspots any notice the sunspot? Whiten a little bit in a day and a half later. Dan a half later our earth became electrified and people didn't really understand at the time. Maxwell's equations weren't articulated they we didn't really understand magnetic fields or relationship to sunspots but in this giant event flair and corona like a part of the sun came off the sun and had had a magnetic field embedded in came hurtling towards earth and it hit our magnetic field and induced a current and this current lit up our earth people could see the northern lights almost down to the equator in the northeast there reports of the northern lights like lighting up the sky. You could read a paper at nighttime and telegraph operators some of them. I'm Komo some of these telegraphs actually caught fires caught fire and some of them could take the batteries out of their end telegraph and it still worked actually so these some of these flares can be pretty intense and on some of these Dwarf Stars called Dorsey Red Dwarf Stars people have observed flares and seeing that some of the flares are as powerful as that Carrington event then amazing so I'm really scaring you off these plants. I mean you know we're not sure how crazy they are but they're pretty crazy. The incredible so so the Carrington event like a essentially what it just created electrical activity just in stationary wires is like you know you're you're holding a light bulb and a light bulb turns on and away or exactly yes and so by the way is separate topic but we're kind of worried that if that event happened today we're in big trouble right because that was my next question grids. It's actually a real concern. You can look this up later and maybe for another show do do an interview on this because there are sort of set of people worried that if this happens we're not really prepared for it right and that was the last the that was the the most recent one we had was over a hundred years ago right right. That's right and but you know I. I don't know if I would hit panic right now. Because if the sun gives off one of these blobs it has to be coming in our direction you the right time. It could give off one of these another time and send it off in another direction. That wouldn't hit earth. I see everyone just to say that. These planets close to the star. They're more more in the line of fire than we are to our son. Everyone's always worried about asteroids coming hitting the earth but we don't worry about what's going on us from the Sun Right Man I love I love thinking about these Red Dwarf Stars are there. Are there any other sort. Dr Strange Planetary Configurations that that you've come across there are and the crazy thing is that we haven't yet found any solar system copies. Although our solar system is hard to find so nearly every type of planet I could construct a like like a picture or visit to so I could mention a couple the other ones sure one of them is again we can and it turns out we can find planets close to the star more easily than we can find planets further away but there are some planets so close to the star way closer to the star than anything. We've been talking about that. The surfaces should be hot enough to melt rock so these planets may have liquid lava lakes that is not from volcanic activity but there are just so heated by the star that there's just molten rock covering the surface another type of planet. I just is love because it's so mysterious our planets that are two to three times the size of earth these planets had the Kepler Space Telescope showed that planet's two to three times the size of earth are the most common type of planet in our galaxy as far as like the kepler parameter space or the Kepler range of planet periods or it's can tell and it's just astonishing because we expected that Jupiter Jupiter sized big planets would be the most common type of planet out there because it's the end member number of planet formation like imagine that planets form it starts out kind of like those dust bunnies under your bed that dust and junk kind of starts collecting in the the material surrounding a stars the stars being born in this material grows kind of like dirty snowball and eventually the dirty snowball will like a cosmic vacuum cleaner suck and everything around it and keep growing until it exhausts food supply if you will and not be a giant planet yet these two planets that are a couple times the size of earth appear to be like ten times more common than Jupiter size planets and so we don't Yan and you know what else is. Our solar system does not have one of those we don't have. We don't have a plan. We don't have a planet that is two to three times the size of earth at all we don't we have. Neptune and your and there are four times the size of earth we have Jupiter. That's eleven times. TMZ Saturn's also very big so it's so baffling right that the most common what might be the most common type of planet out there like we don't have one we don't know what it is as we don't know where it came from and and yeah so though that we have ideas about what it could be but we can't sort through those ideas until we get a lot more information so that means for instance if if the most common kind was the size of Jupiter then we could say okay well then anytime we see one of those that's probably. Jupiter like planet but since we don't have however you are saying one. That's two to three times the size of earth when you detect those you say well. We actually don't know what those plants are like. It is that but it's one more thing I forgot to say that is when you have an extreme and member you can tell what it is like. If I gave you a box and it was so heavy that you could barely lifted like you could guess what's in it right. It has to be like iron or whatever the heaviest thing you can think of right how to be or if I gave you a box. That felt like nothing was in it. You know what it might be that nothing was in it just air yeah so we we can tell things are at the extremists but these planets to three times the size of earth. They just happened to be like intermediate like if I gave you like a medium weight box that was kind of inbetween air and iron like you might not know because it could be so many things so it just turned out that these planets happen to fall in this in between range and they could it'd be a number of different things and we just don't know what they are. We don't even know why would they have formed and started to become big and not continue to grow. It's like meeting yeah. Why why would they have stopped growing so we have a lot of questions about them. I see you know just thinking about the way that you know these. Astronomical bodies form arm is one of the most mind blowing things to me because I overuse the word mind-blowing but I have trouble thinking what other word to use in this sense because the way the way you describe it as you know my understanding is there was one point there's just stuff floating around in the galaxy and then eventually what let's just sort of comes together because of gravity it just sort of coalescence into a lobby ball that happens to be a sphere in most in most cases cases because that's how gravity works and that's just happening randomly. We've got we've got random assortment of of planets just sort of forming in that way it's. I don't know there's something very disorienting to think that everything you know every planet that exists in the in the universe is because of that sort of random collection process I haven't thought of it that way before but it does it does seem a little disheartening in a way that things are just you don't like to think that you existing or your life or whatever happens due to random chance but the fact that our planets that's are just some huge accumulation of random chance does make it look that way well. It's not a I want to be clear. It's it doesn't. I don't think it's negative I do find it somewhat disorienting but what it throws into relief for me. Is that sort of you know what's happening on. Earth is the end of a extreme. You know extreme sequence of random chance after random chance after random chance that that you know there there was a star you know with the correct size that you know the correct type of matter coalesced at the right distance with the right properties and then all all the conditions that are necessary for life to form were on this planet and happen to be stable enough for life to develop to a level where it created this entire new level of complexity of culture which is what we're doing right now. You and I are operating on the level of culture. It's like happenstance after happenstance after happenstance after happenstance and that makes what's going on this planet seem all the more remarkable to me I never agree with people who who make who feel that that devalues life or devalues human life. I think it makes it more valuable. because it you know we're the most remarkable thing happening in the universe but it does make it seem. Maybe less likely that we're going to encounter her. Another another instance of ourselves out there in might actually well. Our Universe is so vast and our galaxy alone has hundreds hundreds of billions of stars and our universe has hundreds of billions of galaxies so it's probably out there somewhere but our media question is out there around one of the nearest stars that we can actually start to probe yeah so I have. I have your that. Some of your early work was on hot jupiters. What are those and how do you like how how how are those surprising things well hot jupiters are jupiter-size or Jupiter mass planets but instead of being like five times the earth Earth's under sense and taking twelve years to go around the sun. These planets are so close to the star the time it takes them to go around the stars only a few days and and having these hot jupiters right up against their star is pretty crazy. 'cause we're confident that there's not enough material for. Jupiter form right close to the star so the thinking is that these big hot jupiters must have formed much further away from their current position and that early on after formation they migrated they interacted with the disc material on moved inwards stopping right close to their star wow so they they moved from one spot in the solar system to another which is not something and normally think of planets doing right right and these hot jupiters the reason. I studied them early on because they were the only thing thing to study and they're easy to find because they're so big and hot and the right close to the star and so that's why studied them initially well. That's some of your old work. I I WANNA talk about Some you know some brand new work on this topic. That's just been done as we're recording this. This episode won't come out until a little bit later on the day that we're recording this. There was a a report just put out that a team believes they found a planet that has water vapor and possibly really even rain. You're quoted in the article. I read about this. I'm just curious for your for your take on this potential discovery because I know it's very early yet yes well. This is one of those mysterious planets that's between two and three times the size of earth that we were talking about. That's one of the most common types of planets in our galaxy so it's a big step a milestone to be able to study its atmosphere because the hope is that eventually the atmosphere will help us know what the planet is made of is the planet like a giant can't waterworld like a scaled up version of one of Jupiter's icy moons. Is it a planet that has like a deep rocky core surrounded by giant envelope of hydrogen. We'd I'd like to eventually be able to discriminate between those so while this new measurement didn't discriminate between them. It's the first time that we've been able to the community. The astronomers have been able to observe the atmosphere Masirah such a such a small one of these mysterious objects so yeah has water vapor in the atmosphere and the authors of one of the two competing papers comed- an argument that the temperature in the atmosphere crosses over that the temperature in the atmosphere might also be suitable for liquid water postulating escalating that there could be water clouds in the atmosphere with water droplets and that's interesting. I it's it's interesting. It's very very very early and we're not we're not entirely sure about the liquid water particularly but the rest of it you you feel confident about. I do well so it's definitely a robust detection of water vapor and it's tough and if this field is tough because planets are so small and the atmospheres are even smaller so just to get any data at all is really a triumph for us and it definitely has water vapor and there's indication that you know we make models to fit the data and we ask what's the best fit model in this case the best fit model shows water but also clouds must be present and if they're clouds they're likely water clouds and so you sort of use reasoning to infer what could be there including the possibility of liquid water droplets yeah. This is such an incredible field because it it seems like so much happening thing almost on a daily basis and you know so many it all feels that that you know the parts of science where it's really really big or really really really small are the ones that take the longest and yet. This is one where it feels like we're we're making progress so quickly. do you share that feeling well yes and no like so as I mentioned I I wrote down about the technique about twenty years ago a few years after that people started the atmosphere. This particular data set took three years to accumulate so someone would have proposed for it. Actually one of the lead authors of lead author run on the papers is one of my former students trained and he must have proposed for the day to four years ago and it took three years to get the data probably like another year to analyze it so from the behind the scenes view. It took quite a long time but I guess it does. It's one of those phrases. This is what they use for. Kids say the days go by slowly but the years go by fast the tediously work on it all. It just seems to occur in a hurry well. It's yeah I I'm not trying to minimize the Labor that goes into it either or or make it sound easy in any way but you know our our understanding of the universe around us is being is being rewritten here it is it really is yes but it's also fair to say that really bright people who are extremely hard workers and ambitious like there's a lot of people funneling into the field to make things happen and so that's partly wires seen so many great results amazing. So what is your. What is your hope for the future of the field. I mean you've talked about it a little bit but what do you hope that new discoveries covers in this field will will bring to humanity large well. My biggest hope more practically is that we can study the very nearest stars like our very nearest neighbors so we can see the planets around them and understand their entire planetary systems and find Earth's if they're there and study the planet atmospheres to look for water and signs of life. That's my immediate goal. I hope finding another earth would help us realize we're not alone like in this universal sense and that will give us some understanding scene of where we've come from and where we might be going well. I couldn't be more fascinated by the work you're doing and I thank you for bringing us that perspective both you know as a scientist and on the show today yeah thank you so much for being here. It's been incredible. Thanks for having me. It's been a fun conversation. All right folks that is it for this week's episode of factually. I WanNa thank Sara seager again for coming on the show and thank you for listening also our wonderful producer. Dana Wiccans a researchers Sam Rodman. I'd like to Andrew W K for letting US use his song. I don't know anything as our theme song and you can follow me on twitter at Adam connery you can follow me at twitch twitch which dot TV slash Adam Connor you WanNa watch me play some video games every now and again. You can sign up for my mailing list. We'll send you a regular fascinating facts. Adam conover dot net mental then. We'll see you next week. contractually thanks for listening.

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