Does Planet Nine Exist? Featuring Dr. Konstantin Batygin

[Music] perhaps one of the rarest of human experiences is discovering a new planet in our solar system in 1846 the planet Neptune was discovered usually credited to her paying lavera a though there were other independent discoverers around the same time this was done through studying perturbations in the motions of the planets something was tugging oddly on the planet Uranus lavera I knew that that there had to be another planet out there since then no further planets have been found other than the discovery of Pluto by Clyde Tombaugh in 1930 which is really a Kuiper belt object of which many more minor planets have been found in recent years but nothing large until perhaps now in recent years it has been noticed that some objects in the outer solar system are perturbed in such a way that another large planet is increasingly suspected to exist beyond the orbit of Neptune my guest today is searching for this hypothesized Planet 9 and zeroing in on it if it's there and should he find out he will become one of a handful of people in the history of science to discover a new planet in our own solar system [Music] welcome to event horizon with John Michael Oda [Music] [Music] [Music] in today's episode John is joined by dr. konstantin batygin assistant professor of planetary science at California Institute of Technology dr. batygin graduated with a bachelor's degree in astrophysics in 2008 he won the Lawrence Tech Award for his thesis the dynamical stability of the solar system he's on the 2015 Forbes list of 30 scientists under 30 who are changing the world dr. Burton welcome to the program it's great to be here now dr. Pat again this is what you're doing in looking for planet 9 you're looking for the first planet we've discovered since arguably clyde tombaugh and pluto but certainly Neptune and what was it 1846 that's right 1846 yeah what led you to suspect that there may be a ninth planet in the outer solar system put succinctly it's the structure of the distant solar system so if you go beyond the orbit of Neptune right so to the outer edges of the solar system what lies beyond is a field of icy debris that is cumulatively known as the Kuiper belt the first Kuiper belt object that was discovered as you already mentioned was actually discovered by Clyde Tombaugh and that is Pluto Pluto is a is a member of a much broader population of icy objects known as the Kuiper belt and if you look at the most distant orbits within the Kuiper belt right so these are things that take 10,000 years to revolve around the Sun one time and what you will note is that all of their orbits point in the same direction roughly and they kind of lie in the same plane so it looks like something is corralling them into into a group into a cluster and really what that what that structure is telling you is that there's a gravitational influence beyond the eight known planets of the solar system and there it exists a ninth planet which lives far far away now how far so our current best estimates place it at an orbit which is about the mean distance is about 500 astronomical units were so 500 times more distance from the Sun as is the earth so this puts it on to kind of a similar orbital period as some of these very long period Kuiper belt objects also about ten thousand years so ten thousand year orbit so this is I guess that would be it would probably be a very elliptical orbit would it yeah so the orbit is unlike those of the rest of the solar system the rest of the solar system orbits are are pretty circular they're maybe out of round by a few percent but nothing too significant Planet 9 has an eccentricity which is which is substantial so it's it's at least 20% probably more like 30% so an extra tricity of 0.3 we used to think back 3 years ago when when we first made the announcement that it was actually more eccentric than that so in the first couple papers I used an eccentricity of 0.6 over the last couple of years have done a tremendous amount of calculations which kind of lowered that best fit by a factor of 2 or so so the next centricity of 0.3 is kind of standard if you look at planets around other stars so extrasolar planets very often will have eccentricities of order 0.3 but is indeed unusual for a solar system object so it would have an eccentric orbit meaning that it would pass closer to the Sun at certain times and further away from the Sun when it was at I suppose that's called the semi-major axis so what how far and how close does it get to the Sun do you think so far that's it that's a great question so I think at closest approach it gets down to maybe 300 astronomical units maybe a tiny bit less maybe 290 but but you really can't push it lo that without ruining the outer solar system's structure that we observed so we know pretty well that its its closest approach is about 300 astronomical units it's farthest approach what we call app helium is somewhat less a somewhat more poorly constrained and that's because in the calculations there's a degeneracy between the semi-major axis and eccentricity to an extent so I can make the orbit of planet 9 slightly bigger at the expense of making it slightly more eccentric and still match the data pretty well so but to kind of give you an overall sense at aphelion so at furthest point it's gonna be about 620 650 something like that now what does that tell you about the size of this object so what's remarkable is that we don't know anything about what planet 9 physically looks like right all we know all that the calculations give us is the mass right because that's all that matters for gravity that said I've earth mass objects are exceedingly common around other Sun like stars in fact as it turns out this is every may be one of the main takeaways from the Kepler mission is that the most common type of planet in the galaxy is a 5 ish earth mass object and these bodies tend to kind of fall into two different categories some of them are only a factor of two bigger than than the earth and and others are are quite a bit bigger maybe a factor of three so we really don't know what the physical radius of Planet 9 is and that's what makes the search so attractive we're looking for something that that we really are have no kind of physical Bayesian prior for we don't know what we're going to find that's always at least since Kepler been somewhat of a mystery why does the solar system not have a super-earth absolutely so this could be our solar system super earth that perhaps got dejected early in the history of the solar system now if that's the case what kind of a planet would this be what what might it look like yeah so I think that as far as the best guess for its its physical structure I think it would be an object which is a large icy core so to speak so it's a it's a big I I small kind of like Uranus and Neptune engulfed in an atmosphere of hydrogen and helium which probably and this is just a educated guess educated by exoplanets probably you know something like three percent or ten percent by mass so if I was to take a guess I would I would assume that it's five Earth masses of ice and rock kind of enveloped by a fraction of an earth mass and Hydra kind of extended hydrogen helium atmosphere and the remarkable thing about an atmosphere like that placed very very far from from the Sun is that it should be quite reflective the theoretical models tell us that such an atmosphere should be basically be what what's called a Rayleigh scattering most of the condensable are gone from the atmosphere but again they were kind of getting into at that point we're getting into more speculative aspects of the theory so you say reflective now that would imply that it would be more detectable of course this is not an easy thing to detect so how do you narrow it down how do you find planet 9 a great question it is so the short answer is it's extremely challenging we don't know where Planet 9 is on its orbit and the reason we don't know that is because all the only observations we have of the distant solar system the Kuiper belt objects themselves are their orbits not the full arcs because as I mentioned earlier it takes 10,000 years for these objects to go around the Sun and we we haven't been alive that long and and so at the end of the day we simply don't know where it is on its orbit but we can use other constraints to to kind of rule out some of fractions of the orbit one such interesting constraint is is actually spacecraft trajectories so planet 9 at closest approach would be at about 300 astronomical units and as far as we can tell that would give rise to a detectable deviation of say the Cassini spacecraft over its course that is not seen so we know it's not at perihelion at closest approach it also be bright enough to be detectable by a conventional surveys at perihelion so we kind of know it's not there but then we kind of rapidly lose precision as you move further and further away from the Sun along the orbit so our best guess always is that it's at close to App Hylian the most distant point along the orbit that more or less must be true not must be true but it's it's likely to be true simply because on a capillary in orbit you spent more time and at aphelion but ultimately we are stuck with the problem of having to explore a pretty large swath of the sky now that's interesting you say the Cassini spacecraft so we can actually tell noticeable deviations of gravitational deviations from spacecraft that are in or were in case of Cassini in the outer solar so what about new horizons can you see anything from that yes a new horizons not so much because new horizons is headed the into the other direction the advantage with Cassini and for this type of calculation Cassini or now remains the only game in town is that it was in orbit for a long long time so you kind of have a large arc of the Saturnian orbit - pretty good precision there's still complications that arise in there namely how do you properly account for all the maneuvers right every time you introduce non-gravitational accelerations you you have to somehow account for that in the model and that introduces errors so there this is still very much kind of an ongoing problem but it is clear I think that if planet nine was at its closest approach to the Sun then you would really see a detectable perturbation onto Saturn and by extension onto Cassini now do you see anything with like Uranus and Neptune perturbed because I recall there used to be and it was discounted but there used to be abnormalities in the orbits of Neptune that made people in the past think maybe there might be a planet out there do you see anything weird with the orbits of the ice giants no and that's that's simply because the data is insufficiently good I mean in with Cassini right you get something like a hundred metres precision which is which is astonishing we just don't know that for merit ease of Uranus and Neptune - to such high precision if my understanding is correct especially over over long periods of time so a lot of this information really does come from spacecraft so you would need to put a spacecraft around in orbit around whatever planet you're you're interested in and then wait for the planet to make a substantial arc around the Sun of course the orbital period of Neptune is 164 years so that's quite a few decades of data collection now what instruments are you using to look for Planet 9 so the primary telescope that we're using is the Subaru telescope the Subaru telescope is the Japanese national observatory it's an amazing eight meter instrument with a huge field of view so the reason Subaru is so useful is because its field of view is large enough to cover a large swath of the sky all at once which is something that we require for the search now even with this amazing instrument however it is taking us a long long time to cover our search area we have a lot of new telescopes coming it's interesting new instruments like the large synoptic survey telescope yep if you don't find it with Subaru telescope do you think that you'll nail it with things like the LSST yeah I think I think that's right LSST will go down to magnitude I think 23 and a half something like that and importantly it will survey the sky multiple times so LSST will if we don't find it by 2022 2023 I think LSST commences in 2022 and we'll get good data by 2023 if we don't find it by then I think LSST will answer the question it'll either just directly find Planet 9 that's option one option two it will at the very least find probably a hundred of these long period Kuiper belt objects so from that point of view we'll be able to do much more precise modeling and constrain the orbit even better and finally it will place observational constraints on the orbit of Planet nine which will actually allow us to zoom in better to where it is on the sky because as you project the orbit onto the night sky and you claim that you did not detect it in this region that region right you kind of exclude more more of the orbit so I think that LSST will be a hugely important instrument if we don't find planet 9 by then my hope is genuinely that we do do you think you have it in a data that you've taken from the Subaru telescope do you think did is your gut feeling that somewhere in that data is planet 9 hard to say it does not look like it with this but we haven't actually gone through all the data yet so you know of course we've only covered about at this point maybe 50% of the search area that that we need so so we're not anywhere we're not done with the survey you know and this first time we got good data in like a year and a half was this past December early December 2018 and there's so much data that we haven't yet shifted through all of it so we'll see we'll see on on first pass doesn't look like it but really we have to be careful so what's the what is your process when you look at the data for example Clyde Tombaugh spent all that time using a blink comparator to look for any kind of movement was as he was looking for Neptune what is the modern process for looking for a planet I mean I assume you're looking for movement of something you know some sort how do you do that that's right so fundamentally the the astronomy of of how you find a moving object in the solar system has not evolved much ultimately all it is is you take a picture of the night sky you come back then that next night you take that same picture and then the night after that and you take another picture all of the same patch of the sky and then you compare the three of course the stars that are that are not in the solar system right things that are in the galaxy remain glued to the to the night sky they don't move things in the solar system move due to parallax now the difference between how Clyde Tombaugh did it and how we do it now is that we they're algorithms that that do it for you so to speak and this is really where my partner-in-crime and collaborator Mike Brown is kind of the expert so so these these algorithms effectively look for identify sources of light on the picture and then look for motion and then so you come up with basically a trainer machine learning algorithm to do it and then comes up with a bunch of candidates and once you have a list of candidates which can be say a thousand or a couple thousand something that a human being can shift through then you just go through it and just do it by eye from that point it's ultimately looking through a thousand images is not is not a particularly difficult thing to do do you do any citizen science i I know that with Kepler there was the planet hunters project where people could actually look manually for transiting exoplanets have you done anything like that yes so with planet 9 search we haven't yet because in part because we've been basically data limited right we got good data back in September 2017 and analyzed that and the first time we got good data since then was this past December so for now we don't really need the citizen science help but I think that's going to be a huge thing once LSST comes online so so I think it's it's more of a issue of how much data we have to play with so we haven't done that yet we might do that in the future and on that we have to go to a break I want to remind everybody to hit subscribe and click the bell for new episodes of this show we'll be right back if you're new to event horizon its subscribe it's free and we upload videos every Thursday plus additional content dr. pitz again welcome back to the program thanks for having me back this idea of captured planets so it's constrained we we can't exactly say that there are ten planets out there there there must only be one or two at best right that's right that's right and in fact you know even before even if you suppose you don't know anything about the Kuiper belt right suppose you've never seen the Kuiper belt you can still ask the question of what is the kind of parameter space that remains in the solar system where you could put a planet and get away with it and that's a calculation that we have done and that's it's gonna be in an upcoming paper called the planet night hypothesis a review paper and as it turns out if you just do this calculation kind of accounting for okay you can't mess up the trajectories of spacecraft you can't mess up the observational surveys meaning that you know there are constraints on bright objects far away from the Sun and also you can't put things so far away that they would get stripped away by passing stars you get a relatively narrow range of parameter space and and then if you ask where does planet nine fall in that kind of island it falls smack in the center of it so it's actually an interesting exercise to do just because it's a completely kind of modeled independent assessment of a where good planet planets be in the solar system no we haven't fed yet found one thing I've noticed about following you know while following the story is that it seems that more and more objects are being identified that have these weird orbits that are suggestive of this planet what is your sense I mean is it possible that it's not there you know or are you convinced that it really is this this must be yes so there's a you know I used to I used to always answer this question would by saying that that I am something like six billion percent sure that plane at nine is there but the more correct answer is that there is indeed a false alarm probability to all this right and that probability is addressing the question of how likely is it that all of these distant orbits that we see that appear to be clustered together in space are just so by chance right and there's a where very well-defined answer to that and the answer is 0.2 percent so I am ninety-nine point eight percent confident that Planet nine really is there now say you find it and we have a ninth planet again depending on how what people feel about Pluto so we find it what does this tell us about star system dynamics can we look for exoplanets out there you know outside of our solar system that does it does it suggest that this is a common phenomena that where you have these weird eccentric outer planets orbiting stars and could this could be common does it give us any information on that on the study of exoplanets what a great question yeah so I think it's this is this is something where it becomes immediately intriguing does it immediately tell us that every sun-like star should have a planet nine equivalent absolutely not because progressively it looks like the solar system itself is kind of an odd ball against the galactic backdrop of of planetary systems right jupiter-like planets are rare we don't have a close-in system of super Earths just the solar system is messed up when you compare it with a typical planet planetary system in the galaxy so does the solar system having some object like Planet 9 tell us anything else about the galaxy no but I think what it would immediately demonstrate or rather the constraints that it would entail would all be on the early formation of the solar system we don't really understand at the detailed level the early formation of the solar system I mean that's just a true statement and discovering Planet 9 and characterizing it will yield constraints that we right now just can't imagine so it'll be huge it'll be a huge improvement in our understanding of the origins of our cosmic home yeah the solar system does seem weird no super earth and then it's got you know rare gas giant how does Saturn play and is Saturn sort of like Jupiter you know is it is it is it rare yeah I mean is that a rare object yes indeed so both Saturn and Jupiter are are strangely uncommon if we kind of believe the current narrative for solar system formation and this narrative is subject to change always but the current kind of iteration of narrative much of the solar systems early evolution was actually shaped by the interplay the gravitational interplay between Jupiter and Saturn so we would have had a very very different planetary system if we only had one of them so so there's there's all this detail which for now we're just as planet formation theorists just shifting through right and and we're not you know really it's it's only kind of been in the last decade decade and a half that we've began to really uncover the rule that Jupiter and Saturn's early migration their movement through the solar system played so there's just a tremendous amount of work left to do in this domain now this is somewhat of an offbeat question but if you know we one of the ways that that astronomers look for exoplanets is as I recall the radial velocity method where are you looking for wobbles in the start is planet nine too far away for us to have a measurable effect that we could look at with regarding the sun's movement yeah that's right and really the the answer that it is is the movement itself is tiny and also that movement is happening over the orbital period of the planet right so it's it's King that reflux velocity of the Sun in order to see it you'd have to observe the Sun for 10,000 years and although I am indeed planning to live on as a cyborg forever you know for now that that type of observation is out of reach watching the Sun for 10,000 years looking for a planet now you say you want to live on as a cyborg uh-huh are you sure you would you would you rather just live on as a uploading yourself into a computer rather than becoming a horrible cyborg what a great question yeah I mean I haven't I haven't given this sufficient thought to really make the distinction um yeah I don't know maybe maybe I prefer to be just software now actually now that I really think about it I think I'd prefer to have some hardware to why I would imagine you could switch back and forth if you want to just download yourself into a cyborg body if you if that's useful for you at the moment and then you can go back to being in the cloud at your leisure now it's weird some days I feel like I do that already what well without the coffee I I feel as though I'm yeah I'm a different person without the coffee than I am women when I actually I have it now once this object is found it's gonna have to have a name and I know that there's all sorts of procedural stuff from the IAU on determining what what to name an object and we've so far with the planets we we have legacy names from the greco-roman world you know do you have a favorite name that you would like for planet night I don't but then I also kind of do so we're we're all out of greco-roman gods at this point all of them have been assigned to asteroids and Kuiper belt objects I think the demigod of untied shoelaces might still be available so so that's one option definitely yeah you know it's interesting the name is something that neither me nor Mike my partner in crime we never talked about it and that's that's in part kind of a kind of a superstitious thing right it's it's not good to name things that you haven't imaged yet but this did not stop a group of enthusiasts from creating a change.org page which is addressed to yours truly as well as the IAU and and their their suggestion is to name Planet nine David Bowie because David Bowie died maybe a week before we made the announcement back in 2016 and I've kind of grown to like that suggestion a lot because then you could have a whole kind of David Bowie entomology if you will wicker you can you know you can name the satellites Ziggy Stardust and stuff you know it'd just be it'll just be a cute way to do it I am of course joking but only only partially half joking about naming a planet David Bowie yeah you know how sweet would that be you know you just forever you know forever demand people to whenever they refer to it in scientific literature to refer to it as Planet Bowie you know Uranus was before it was called Uranus was called George basically giorgia Citian so and Jupiter Saturn and George George by the way is another good name for a planet George yeah I well I wonder too there actually is something from the greco-roman Pantheon that has not been named and it's the the Romans particularly would build temples to the unknown God so you can name it unknown you know that's or untitled untitled untitled like those uh you know documents on your computer that's a good one you know untitled but in parentheses David Bowie yes that's right love it alright dr. Fitts Hagen thank you for joining us today we've run out of time and I hope you'll come back with us especially after you find the planet no thanks so much for having me this was so much fun the discovery of a ninth planet in our solar system will be among the chief scientific discoveries of the 21st century and it does increasingly look like it's probably out there it's fun to imagine what it might like and if we do find it when we visited there will once again be a planet in our solar system that we've never seen up close and if it is a core of a gas giant what would that be like with any luck these will be questions we will be asking relatively soon and indeed Planet nine could be found at any time I look forward to what we learn about it John yes Anna I'm guessing you have a suggestion of course I do well go on then lay it on me ooh 2.0 what blue 2 you're suggesting we name it blue - well I suppose that's close enough I like it but I'm going with Neptune this isn't a cartoon John if it were you'd probably have better script writers Anna you wrote the script John no that was Erin joining me next week will be historian reenactor and YouTube personality John Townsend for a little bit different type of a show themed on history see you then [Music]

Channel: Event Horizon

Views: 259,879

Rating: 4.8365426 out of 5

Keywords: planet nine, universe, astronomy, mystery, nibiru, sitchin, exoplanet, rogue, oort, kuiper, perturbation, anunaki, solar system, jupiter, venus, earth, comet, uranus, neptune, discovery, batygin, godier, astrophysics, caltech, object, planet nine documentary, planet nine update, planet 9 update, planet 9 2019, planet 9 orbit, planet 9 discovery, where is planet x, planet x, does planet x exist?, mike brown, alien, isaac arthur, does planet nine exist?

Id: gG58idb6HuA

Length: 33min 51sec (2031 seconds)

Published: Sat Feb 23 2019