Episode 355·Deep read
David Kipping: Alien Civilizations and Habitable Worlds
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Lex Fridman Podcast #355 – David Kipping: Alien Civilizations and Habitable Worlds
Machine transcription by Qwen3-ASR 0.6B (MLX, local, Apache-2.0). May contain recognition errors.
The following is a conversation with David Kipping, an astronomer and astrophysicist at Columbia University, director of the Cool Worlds Lab, and he's an amazing educator about the most fascinating scientific phenomena in our universe. I highly recommend you check out his videos on the Cool Worlds YouTube channel. David quickly became one of my favorite human beings. I hope to talk to him many more times in the future. And now a quick few second mention of each sponsor. Check them out in the description. It's the best way to support this podcast. We got Simply Safe for home security, Shopify for e commerce, and ExpressVPN for privacy on the internet. Choose wisely, my friends. And now onto the full ad reads as always no ads in the middle. I find those annoying. So I try my best to make sure we don't have any. But if you skip these, please still check out the sponsors. I mean, without them, this podcast would not be possible. 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I was like, "Yeah," and together through that. There's like I don't know his life story. He doesn't know my life story, and I think there was a joint celebration of two lives that at least for time. Have enjoyed the hell out of some Metallica. So what can I say? Anyway, sign up for a one dollar per month trial period at Shopify dot com slash lex. All lowercase. Get a Shopify dot com slash lex pod for an extra three months free. This is Alex Friedman podcast. To support it, please check out our sponsors in the description. And now dear friends, here's David Kipping. Your research at Columbia is in part focused on what you call Cool Worlds or worlds outside our solar system where temperature is sufficiently cool to allow for moons, rings, and life to form and for us humans to observe it. So can you tell me more about the idea this place of Cool Worlds? Yeah, the history of discovering planets outside our solar system was really dominated by these hot planets, and that's just because of the fact they're easier to find. When the very first methods came online, these were primarily the Doppler spectroscopy method looking for wobbling stars, and also the transit method, and these two both have a really strong bias towards finding these hot planets. Now, hot planets are interesting. The chemistry in their atmosphere is fascinating. It's very alien. An example of one that's particularly close to my heart is Trace Two B, whose atmosphere is so dark it's less reflective than coal, and so they have really bizarre photometric properties. Yet at the same time, they resemble nothing like our own home. And so it said that there's two types of astrophysicists: the astrophysicists who care about how the universe works. They want to understand the mechanics of the machinery of this universe. Why did the Big Bang happen? Why is the universe expanding? How a galaxy's formed? And there's another type of astrophysicist which perhaps. Speaks to me a little bit more. It whispers into your ear, and that is why are we here? Are we alone? Are there others out there? And ultimately along this journey, the hot planets aren't going to get us there. We when we're looking for life in the universe, seems to make perfect sense that there should be planets like our own out there, maybe even moons like our own planet around gas giants that could be habitable. And so my research has been driven by trying to find these more terracous globes that might resemble our own planet. So they're the ones that lurk more in the shadows in terms of how difficult it is to detect. They're much harder. They're harder for several reasons. The method we primarily use is the transit method. So this is really eclipses as the planet passes in front of the star. It blocks out some starlight. The problem with that is that not all planets pass in front of their star. They have to be aligned. Correctly from your line of sight, and so the further way the planet is from the star, the cooler it is, the less likely it is that you're going to get that geometric alignment. So whereas a hot Jupiter about one percent of hot Jupiters will transit in front of their star, only about. Point five percent, maybe even a quarter of a percent of Earth-like planets will have the right geometry to transit, and so that makes it much much harder for us. What's the connection between temperature of the planet and geometric alignment, probability of geometric alignment? There's not a direct connection, but they're connected by an intermediate parameter which is their separation from the star. So the planet will be cool if it's further away from the star, which in turn means that the probability of getting that alignment correct is going to be less. On top of that, they also transit their star less frequently. So if you go to the telescope and you want to discover a hot Jupiter, you could probably do it in a week or so because the orbit period is of order one, two, three days. So you can actually get the full orbit two or three times over. Whereas if you want to set an Earth-like planet, you have to observe that star for three, four years, and that's actually one of the problems with Kepler. Kepler was this very successful mission that NASA launched over a decade ago now I think, and it discovered thousands of planets. It's still the dominant source of exoplanets that we know about, but unfortunately it didn't last as long as we would have liked it to. It died after about four point three five years I think it was, and so for an Earth-like planet that's just enough to catch four transits. A four transits was kind of seen as the minimum, but of course the more transits you see, the easier it is to detect it because you build up signal to noise. If you see the same thing, tick tick tick tick tick, the more ticks you get, the easier it is to find it. And so it was really a shame that Kepler was just at the limit of where we were expecting it to start to see Earth-like planets, and in fact it really found zero. Zero planets that are around stars like the sun, a orbit similar to the Earth around the sun, and could potentially be similar to our own planet in terms of its composition, and so it's a great shame, but that's why it gives astronomers more to do in the future. Just to clarify, the transit method is our primary way of detecting these things, and what it is is when the object passes occludes the source of light just a tiny bit, a few pixels, and from that we can infer something about its mass and size and distance and geometry all of that. That's like trying to tell. What at a party you can't see anything about a person, but you can just see by the way they occlude others. So this is the method. But is this a super far away? How many pixels of information do we have? Basically, how high resolution is the signal that we that we can get about these occlusions? You're right in your description. I think just to build upon that a little bit more, it might be almost like your vision is completely blurry, like you have an extreme you know hyperscription, and so you can't resolve anything, everything's just blurs, and but you can tell that something was there because it just got fainter for a short amount of time. Something someone passed in front of a light, and so that light. In your eyes would just dim for a short moment. Now the reason we have that problem with blueness or resolution is just because the stars are so far away. I mean these are the closest stars are four light years away, but most of the stars Kepler looked at were thousands of light years away. And so there's absolutely no chance that the telescope can physically resolve the star or even the separation between the planet and the star is or is too small, especially for a telescope like Kepler. It's only a meter across. In principle, you can make those detections, but. You need a different kind of telescope. We call that direct imaging, and direct imaging is a very exciting distinct way of detecting planets. But it, as you can imagine, is going to be far easier to detect planets which are really far away from their star to do that because that's going to make that separation really big, and then you also want the star to be really close to us, so the nearest stars. Not only that, but you would prefer that planet to be really hot because the hotter it is, the brighter it is, and so that tends to bias direct imaging towards planets which are in the process of forming. So things which have just formed the planet still got all of its primordial heat embedded within it, and it's glowing. We can see those quite easily, but for the planets more like the Earth, of course they've cooled down, and so we can't see that the light is pitiful compared to a newly formed planet. We would like to get there with direct imaging. That's the dream is to have the pale blue dot, an actual photograph of it, maybe even just a one pixel photograph of it. But for now the entire solar system is one pixel, certainly with the transit method most of the telescopes, and so all you can do is see where that one pixel which contains potentially dozens of planets and the star, maybe even multiple stars, dims for a short amount of time. It dims just a little bit, and from that you can infer something. Yeah, I mean it's it's like being a detective in the scene, right? It's very it's indirect clues of the existence of the planet. It's amazing the humans can do that. We're just looking out in these immense distances. And looking, you know if there's alien civilizations out there, like let's say one exactly like our own, we're like, would we even be able to see an Earth that passes. In the way of its sun and slightly dims, and that's the only sign we have of that of that alien human-like civilization out there. Is it just a little bit of a dimming? Yeah, I mean depends on on the type of star we're talking about. If it is a star truly like the sun, the dip that that causes is eighty four parts per million. I mean that's just it's like the same as a, as like a firefly flying in front of like a giant floodlight at a stadium or something. That's the kind of the brightness contrast that you're trying to compare to. So it's it's extremely difficult detection. And in the very, very best cases, we can get down to that. But as I said, we don't really have any true Earth analogs that have been in the exoplanet candidate yet. Unless you relax that definition, you say it's not just doesn't have to be a star just like the sun. It could be a star that's smaller than the sun. It could be these orange dwarfs or even the red dwarf stars, and the fact those stars are smaller means that for the same size planet passing in front of it, more light is blocked out. And so a very exciting system, for example, is Trappis one, which has seven planets which are smaller than the Earth, and those are quite easily detectable not with a space based telescope even from the ground, and that's just because the star is so much smaller that the relative increase in or decrease in brightness is enhanced significantly because that smaller size. So Trappis one e, it's a planet which is in the right distance for liquid water. It has a slightly smaller size than the Earth. It's about ninety percent the size of the Earth, about eighty percent the mass, and it's one of the top targets right now for potentially having life. And yet it raises many questions about what would that environment be like. This is a star which is one eighth the mass of the sun. It's stars like that take a long time to come off that adolescence. When stars first form like the sun, it takes them maybe ten hundred million years to sort of settle in to that main sequence lifetime. But for stars like these late M dwarfs as we call them, they can take up to a billion years or more to calm down, and during that period they're producing huge amounts of X rays, ultraviolet radiation that could potentially rip off the entire atmosphere. It may desiccate the plants in the system, and so even if water arrived by comets or something, it may have lost all that water due to this prolonged period of high activity. So we have lots of open ended questions about these M dwarf planets, but they are the most accessible, and so. In the near term, if we detect anything in terms of biosignatures, it's going to be for one of these red dwarf stars. It's not going to be a true Earth twin, as we would recognize it as having a yellow star. Well, let me ask you. I mean, there's a million ways to ask this question. I'm sure I'll ask it about habitable worlds. Let's just go to our own solar system. What can we learn about the planets and moons in our solar system that might contain life, whether it's Mars or some of the moons of Jupiter and Saturn? What kind of characteristics? Because you said it might not need to be Earth-like, what kind of characteristics might be we be looking for? When we look for life, it's hard to define even what life is, but we can maybe do a better job in defining the sorts of things that life does, and that provides some aspects to some avenue for looking for them. In the classically conventionally, I think we thought the way to look for life was to look for oxygen. Oxygen is a byproduct of photosynthesis on this planet. We didn't always have it. Certainly, if you go back to the Archean period, there was you know you have this period called the Great Oxidation Event where the Earth floods with oxygen for the first time and starts to saturate the oceans and then the atmosphere. And so that oxygen, if we detect it on another planet, whether it be Mars, Venus or an exoplanet, whatever it is, that was long thought to be evidence for something doing photosynthesis because if you took away all the plant life on the Earth, the oxygen wouldn't just hang around here as a highly reactive molecule. It would oxidize things, and so within about a million years, you would probably lose all the oxygen on planet Earth. So that was a conventionally how we thought we could look for life, and then we started to realize that it's not so simple because a there might be other things that life does apart from photosynthesis. Certainly, the vast majority of Earth's history had no oxygen, and yet there was living things on it, so that doesn't seem like a complete test. And secondly, could there be other things that produce oxygen besides from life? A growing concern has been these false positives in biosignature work, and so one example of that would be photosynthesis that happens in the atmosphere. When ultraviolet light hits the upper atmosphere, it can break up water vapor. The hydrogen splits off to the oxygen. The hydrogen is a much lighter atomic species, and so it can actually escape. Certainly, plants like the Earth's gravity. That's why we don't have any hydrogen or very little helium. And so that leaves you with the oxygen, which then oxidizes the surface, and so there could be a residual oxygen signature just due to this photosynthesis process. So we've been trying to generalize, and certainly in recent years there's been other suggestions of things we could look for in the solar system beyond nitrous oxide, basically laughing gas, is a product of microbes. That's something that we're starting to get more interest in looking for methane gas in combination with other gases can be an important biosignature. Phosphine, as well, and phosphine is particularly relevant to the solar system because there was a lot of interest for Venus recently. You may have heard that there was a claim of a biosignature in Venus's atmosphere. It was like two years ago now, and the the judge and jury still out on that. There was a very provocative claim and signature of a phosphine-like spectral absorption. But it could have also have been some of the molecule in particular sulfur dioxide, which is not a biosignature. So this is a detection of a gas in the atmosphere of Venus, and and it might be controversial on several dimensions. So one how to interpret that, two is this there a gas, and three is this even the right detection is this is there an error in the detection. Yeah, I mean how much do we believe the detection in the first place? If you do believe it, does that necessarily mean there's life there? And what gives? How can you have life in Venus's atmosphere in the first place? Because that's you know been seen as like a hellhole place for imagining life, but I guess the the counter that has been that okay yes the surface is a horrendous place to imagine life thriving. But as you go up in altitude, the very dense atmosphere means that there is a cloud layer where the temperature and the pressure become actually fairly similar to the surface of the Earth, and so maybe there are microbes stirring around in the clouds which are producing phosphine. At the moment, this is fascinating. It's got a lot of us reinvigorated about the prospects of. Going back to Venus and doing another mission there. In fact, there is now two NASA missions, Veritas and Da Vinci, which are going back and before twenty thirty to the twenty thirty s, and then we have a European mission. I think that slated now, and even a Chinese mission might be coming along the way as well. So we might have multiple missions going to Venus, which has long been overlooked. I mean, apart from the Soviets, there really has been very little in the way of exploration of Venus, certainly as compared to Mars. Mars has enjoyed most of the activity from NASA's rovers and surveys, and Mars is certainly fascinating. There is you know the signature of methane that has been seen there before. Again, there the discussion is whether that methane is a product of biology, which is possible, something that happens on the Earth, or whether it's some geological process that we are yet to fully understand could be a for example a reservoir of methane that's trapped under the surface and it's leaking out seasonally. So the nice thing about Venus is if there is a giant living civilization there, it'll be airborne so you can just fly through and collect samples. With Mars and moons of Saturn and Jupiter, you are going to have to dig dig under to find the civilizations dead or living. Right, and so yeah, maybe it's easier than for Venus because certainly you can imagine just a balloon floating through the atmosphere that or a drone or something that would have the capability of just scooping up and sampling to to dig under the surface of Mars is maybe feasible ish with you know especially with something like Starship that could launch you know a huge digger basically to the surface and you could just excavate away at the surface but for something like Europa we really are still unclear about how thick the ice layer is how you would melt through that huge thick layer to get to the ocean and then potentially also discussions about contamination the problem with looking for life in the solar system which is different from looking for life with exoplanets is that you always are in the risk of especially if you visit there of introducing the life yourself right it's very difficult to completely exterminate every single microbe and spore on the surface of your of your rover or the surface of your lander and so there is always a risk of introducing something I mean to some extent there is continuous exchange of material between these planets naturally on top of that as well and now we're sort of accelerating that process to some degree and so if you dig into Europa's surface which probably is completely pristine it's very unlikely there has been much exchange with the outside world for its subsurface ocean you are for the first time potentially introducing bacterial spores into that environment that may compete or may introduce various signatures for the life you are looking for and so it's it's almost an ethical question as to how to proceed with looking for life on those subsurface oceans and I don't think one we've really have a good resolution for this point ethical so you mean ethical in terms of concern for the like for preserving life elsewhere not like not to murder it as opposed to scientific one I mean we always worry about a space virus right coming coming here or you know some kind of external source and we would be the source of that potential contamination or the other direction yeah I mean they that you know the whatever whatever survives in such harsh conditions might be pretty good at surviving all conditions it might be a little bit more resilient and robust so it might actually take a ride on us back home possibly I mean I am sure I am sure that some people would be concerned about that I think we would we would hopefully have some containment procedures as if if we did sample return or you mean you don't even really need a sample return these days you can pretty much send it like a little micro laboratory to the the planet to do all the experiments in situ and then just send them back to your planet the data and so I don't think there is is necessary that especially for a case like that where you might have contamination concerns that you have to bring samples back although probably if you brought back European sushi it would probably sell for quite a bit with the billionaires in New York City sushi yeah I would love from an engineering perspective just to see all the different candidates and designs for like the scooper for Venus and the scooper for Europa and and Mars haven't really looked deeply into how they actually like the actual engineering of collecting the samples because that's the engineering of that is probably essential for not either destroying life or or polluting with our own microbes and so on so that's like an interesting engineering challenge I usually for rovers and stuff focus on the on the robot on the sort of the mobility aspect of it on the robotics the perception and the movement and the planning and the control but there is probably the scooper is probably where the action is the microscopic sample collection so basically you have to first clean your vehicle make sure it doesn't have any Earth like things on it and then you have to put it into some kind of thing that's perfectly sealed from the environment so if we bring it back or we analyze it it's not it's not going to bring anything else external in yeah I don't know that would be an interesting engineering design there yeah I mean curiosity has been leaving these little pods on the surface quite recently there is some neat photos you can find online and it's they kind of look like a lightsaber hilts which so yeah to me I think I tweeted something like you know this weapon is your life like don't lose curiosity because it's just dumping these little vials everywhere and it's yeah it is scooping up these things and the intention is that in the future there will be a sample return mission that will come and pick these up but it's I mean the engineer behind those things is so impressive the thing that blows me away the most has been the landings especially I am trying to be a pilot at the moment so that's the sort of you know watching landings has become like my pet hobby on YouTube at the moment and how not to do it how to do it with different levels of conditions and things but with the you know when we think about landing on Mars just the light travel time effect means that there is no possibility of a human controlling that descent and so you have to put all of your faith and your trust in the computer code or the AI or whatever it is that you've put on board that thing to to make the correct descent and so there is this famous period called seven minutes of hell where you are basically waiting for that light travel time to come back to know whether your vehicle successfully landed on the surface of not and during that period you know in your mind simultaneously that it is doing these multi stages of deploying its parachute deploying the crane activating its jets to come down and controlling its descent to the surface and then the crane has to fly away so it doesn't accidentally hit the rover and so there is a series of multi stage points where any any of them go wrong you know the whole mission could could go awry and so the fact that we are fairly consistently able to build these machines that can do this autonomously is to me one of the most impressive acts of engineering that NASA have achieved yes the unfortunate fact about physics is the takeoff is easier than the landing yes and you mentioned Starship one of the incredible engineering feats that you get to see is the reusable rockets that take off but they land and they land using control and they do so perfectly and sometimes when it's synchronous it's it's just it's beautiful to see and then with Starship you see the the chopsticks that catch the ship I mean there is so much incredible engineering but you mentioned Starship is somehow helpful here so what's your hope with Starship what kind of science might it enable possibly there is two things I mean it's the launch cost itself which is hopefully going to mean per kilogram is going to dramatically reduce the cost of it's the sort of the level even if it's a factor of ten higher than what Elon originally promised this is going to be a revolution for the cost to launch that means you could do all sorts of things you could launch large telescopes which could be basically like JWST but you don't even have to fold them up JWST had this whole issue with its design that it's six and a half meters across and so you have to there is no fuselage which is that large at the time there is thought wasn't large enough for that and so they had to fold it up in this kind of complicated origami and so a large part of the cost was figuring out how to fold it up testing that it unfolded correctly repeated testing and you know there was something like one hundred thirty fail points or something during this unfolding mechanism and so all of us were holding our breath during that process but if you have the ability to just launch you know arbitrarily large masses at least comparatively compared to JWST and very large mirrors into space you can more or less repurpose ground based mirrors the Hubble Space Telescope mirror and the JWST mirrors are designed to be extremely lightweight and that increased their cost significantly they have these kind of honeycomb design on the back to try and minimize the the weight if you don't really care about weight because it's so cheap then you could just literally grab many of the existing ground based mirrors across telescopes across the world four meter five meter mirrors and just pretty much attach them to a chassis and have your own space based telescope I think the Breakthrough Foundation for instance is an entity that has been interested in doing this sort of thing and so that raises the prospects of having not just one JWST that just you know JWST is a fantastic resource but it's split between all of us cosmologists star formation astronomers those of us studying exoplanets those of us wanting to study you know the ultra deep fields and the origin of the first galaxies the expansion rate of the universe everyone has to share this resource but we could potentially each have you know one JWST each that is maybe just studying a handful of the brightest exoplanet stars and measuring their atmospheres this is important because if you know we talked about this planet Trappis one E earlier that planet if JWST stared at it and tried to look for biosignatures by which I mean oxygen nitrogen oxide methane it would take it a order of two hundred transits to get even a very marginal what would call two and a half sigma detection of those which basically nobody would believe with with that and a hundred transits I mean this thing transits once every six days so you are talking about sort of four years of staring at the same star with one telescope there be some breaks but it be hard to schedule much else because you have to continuously catch each one of these transits to build up your signal to noise and so JWST is never going to do that in principle technically JWST could technically have the capability of just about detecting a biosignature on an Earth like planet around around a non Sun like star but still impressively we have basically the technology to do that but we simply cannot dedicate all of its time practically to that one resource and so Starship opens up opportunities like that of mass producing these kinds of telescopes which will allow us to survey for life in the universe which of course is one of the grand goals of astronomy I wonder if you can speak to the the bureaucracy the political battles the scientific battles for for time on the James Webb telescope is there there must be a fascinating it's process of scheduling that all scientists they are trying to collaborate and figure out what the most important problems are and there is an interesting network of interfering scientific experiments probably have to somehow optimize over it's it's a really difficult process I don't envy the tech that are going to have to make this decision we call it the tech the time allocation committee that that make this decision and I've served on these before and it's very difficult I mean typically for Hubble we we were seeing at least ten sometimes twenty times the number of proposals for telescope time versus available telescope time for JWST there has been one call already that has gone out we called it cycle one and that was oversubscribed by I think something like six to one seven to one and the cycle two which is just been announced fairly recently and the deadline is actually the end of this month so my team are totally laser focused on running our proposals right now that is expected to be much more competitive probably more comparable to what Hubble saw and so it's hard more competitive than the cycle one you said already because that's already more competitive than the first cycle so I said the first cycle of James Webb was about six to one and this will probably be more like twenty to one I would expect so these are all proposals by scientists and so on and it's not like you can schedule at any time because if you are looking for transit times yeah you have you have a time critical element yes time critical element and they're conflicting in non like non obvious ways because the the frequency is different the duration is different there is probably computational needs they are different the there is a type of sensors the direction pointing all that yeah it's hard and there are certain programs like doing a deep field study where you just more or less point the telescope and that's pretty open I mean you are just accumulating photons you can just point at that that patch of the sky whenever the telescope is not doing anything else and just get your month let's say a month of integration time is your is your goal over the lifetime of JWST so that's maybe a little bit easier to schedule it's harder especially for us looking at cool worlds because as I said earlier these these planets transit very infrequently so we have to wait if you are looking at the Earth transiting the Sun an alien watching us they they would only get one opportunity per year to do that observation the transit lasts for about twelve hours and so if they don't get that time it's hard that's it if it conflicted with another proposal that wants to do use the another time critical element it's much easier for planets like these hot these hot planets or these close in planets because they transit so frequently there is maybe a hundred opportunities and so then the tech can say okay they want ten transits there is a hundred opportunities here it's easier for us to give us to give them time we're almost in the worst case scenario we're proposing to look for exoplanets around two cool planets and so we really only have one bite of the cherry for each one and so our sales pitch has been that these are extremely precious events and more importantly JWST is the only telescope the only machine humanity has ever constructed which is capable of finding moons akin to the moons in our solar system Kepler can't do it even Hubble can't do it JWST is the first one and so there is a new window to the universe because we know these moons exist they they're all over the place in the solar system you have the moon you have Io Callisto Europa Ganymede Titan lots of moons of fairly similar size sort of thirty percent the size of the Earth and this telescope is the first one that can find them and so we are very excited about the profound implications of ultimately solving this journey we're on in astronomy which is to understand our uniqueness we want to understand how common is the solar system are we the way are we the architecture that frequently emerges naturally or is there something special about what happened here I think this is not the worst case the best case it's obvious it's super rare so you have to like I would so I love scheduling from a computer science perspective that's my background so algorithmically to solve a schedule problem I will schedule the rarest things first and obviously this is the the JWST is the first thing that can actually detect a cool world so this is a big new thing you can show off that new thing happens rarely schedule it first it's perfect you should be in the tech this is perfect I will I'll file my application after we're done with this I you know this part of me is the OCD part of me is the computational aspect I love scheduling a computing device because you have that kind of scheduling on supercomputers on that scheduling problem is fascinating how do you prioritize computational how do you prioritize science data collection sample collection all that kind of stuff it's actually kind of it's kind of fascinating because data in ways you expect and don't expect will unlock a lot of solutions to some fascinating mysteries and so collecting the data and doing so in a way that maximizes the possibility of discovery is really interesting like from a computational perspective I agree there is a real satisfaction in extracting the maximum science per unit time exactly out of your telescope and that that's that's the tech's job but the the tech are not machines they're not a piece of computer code they will make their selections based off human judgment and a lot of the telescope is certainly within the field of exoplanets because there is different fields of astronomy but within the field of exoplanets I think a good expectation is that most of the telescope time that JWST have will go towards atmospheric retrieval which is sort of alluded to earlier you know like detecting molecules in the atmospheres not biosignatures because as I said it's really not designed to do that it's pushing JWST probably too far to expect to do that but it could detect for example a carbon dioxide rich atmosphere on Trappis one E that's not a biosignature but you could prove it's like a Venus in that case or maybe like a Mars in that case like both those have carbon dioxide rich atmospheres doesn't prove or disprove the existence of life either way but it is our first characterization of the nature of those atmospheres maybe we can even tell the pressure level and the temperature of those atmospheres so that's very exciting but there is we we are competing with that and that I I think that science is completely mind blowing and fantastic we have a completely different objective which is in our case to try and look for the first evidence of these small moons around these planets potentially even moons which could be habitable of course so I think it's a very exciting goal but um tech has to make a human judgment essentially about which science are they most excited by which one has the highest promise of return the most highest chance of return and so that's hard because if you look at a planetary atmosphere well you know most of the time the planet has an atmosphere already and so there is almost a guaranteed success that you are going to learn something about the atmosphere by pointing JWST at it whereas in our case there is a harder sell we are looking for something that we do not know for sure exists yet or not and so we are pushing the telescope to do something which is inherently more risky yeah but the existence if shown already gives a deep lesson about what's out there in the universe that means that other stars have similar types of variety as we have in our solar system they have an Io they have a Europa and so on which means like there is a lot of possibility for icy planets for water for planets that enable planets and moons that I mean that that's super exciting because that that means everywhere through our galaxy and beyond there is just innumerable possibility for weird creatures I agree life forms you don't have to convince me I mean yeah NASA has been on this quest for a long time and it's sometimes called Eter Earth it's the frequency of Earth like usually they say planets in the universe how common are planets similar to our Earth in terms of ultimately we'd like to know everything about these planets in terms of the amount of water they have how much atmosphere they have but for now it's kind of focused just on the size. And the distance from the star essentially how how often do you get similar conditions to that, um that was Kepler's primary mission and it really just kind of flirted with the answer didn't quite get to a definitive answer, but I would say look if we're looking if if that's our primary goal to look for Earth like, I would say worlds, then moons has to be a part of that because we know that um Earth like from the Kepler data the preliminary results that Earth like planets around sun like stars is not, an inevitable outcome it seems to be something like a one to ten percent outcome so it's not particularly inevitable that happens but we do often see about half of all sun like stars have either a mini Neptune a Neptune or a Jupiter in habitable zone of their stars that's a very very common occurrence that
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