Breaking News on the Search for Planet Nine with Dr. Konstantin Batygin

[Music] you have fallen into event horizon with john michael godier [Music] in today's episode john is joined by dr constantine battigan assistant professor of planetary science at california institute of technology dr battigan graduated with a bachelor's degree in astrophysics in 2008. he won the lauren steck award for his thesis the dynamical stability of the solar system he is on the 2015 forbes list of 30 scientists under 30 who are changing the world constantine battigan welcome back to the program hey thanks it's great to be back now constantine eccentricity with planet nine messing around with the kuiper belt in ways that hadn't been realized until your new paper give us an overview about the ideas that planet nine may be more eccentric than was originally envisioned look the simple story is in the thousands of calculations that we had run to date we viewed the solar system really is an isolated object right as far as our simulations were concerned it was the universe but of course that's not true and that's not how the solar system formed the solar system formed in a dynamic environment with thousands of other sun-like stars and you know smaller and bigger stars all forming together in a cluster in such a cluster an inescapable consequence of planet formation is that you create this almost spherical quasi i would say go as far as to say maybe quasi-toroidal quasi-spherical structure cloud around the solar system filled with icy debris that we conventionally now call the oort cloud particularly the inner port cloud if planet nine is there this oort cloud does not simply remain static instead it gets re-injected back into the solar system and if this process is active this means that at the quantitative level our simulations that we have performed to date were incomplete and if you account for this effect this would mean that planet nine in order to match the data that we see right now would have to be marginally more eccentric than we previously thought now does this uh support an origin say planet nine's there does it support any kind of an origin for it as in does the eccentricity indicate that it could be an ejected object from the inner solar system or a captured object from somewhere else it's a tough question to answer simply because if you go through the possibilities for how planet nine could have acquired its final orbit there are three that you can immediately put on the table the first is that it formed where it is the second is that it got captured and the third is that it got ejected from sort of the uranus neptune jupiter and saturn planet formation region and was perturbed somehow onto a more circular orbit than it originated with of those three only the final one is plausible the reason is that in order to form where it is the protoplanetary disk the solar system would have had to extend to a sort of absurd distances and and we simply don't see planetary disks protoplanetary disks as large as that other reasons why in the solar system in particular we think the disk ended at about neptune's current orbit but i think it's not worth it to to go into that in too much detail the capture story is one that's really interesting from kind of a sci-fi point of view it definitely would make the best screenplay but unfortunately it doesn't work on a quantitative level because the same it's kind of sort of like the same encounters with stars that could could lead to a passing star dropping off planet nine in the sun's orbit the next encounter would have an equally large probability of stripping planet nine away so it's a highly unlikely way to create planet nine the third scenario where it forms kind of where uranus and neptune are and then gets ejected and then gets circularized is one that is plausible but i should say at the detailed level the probabilities there also require a very specific type of star cluster for it to work well if it formed in the solar system in that sort of region where neptune and uranus and all that formed at the time in the early solar system that was closer into the sun right uh yeah that's right so this would have been sort of 10 a.u kind of close to where saturn is right now maybe marginally bigger than that but not too much so indeed the solar system started out in a more compact configuration and then within the first maybe 10 maybe 100 million years suffered a dynamical instability wherein the planets kind of migrated out through a stochastic process so indeed this would been somewhat closer to the sun than neptune is today so to speculate to imagine what planet nine might be like could it simply be like an ice giant like uranus or neptune that that just ended up way out there through gravitational interaction is that more likely or is it going to be more like a kuiper belt object where it's actually rocky i mean can we infer anything based on that well look as far as the what the calculations can tell you right the type of calculations that we do all they can tell you is a mass and an orbit right they cannot tell you if planet nine is a five earth mass burrito or a five earth mass rock or a five earth mass ice ball or really anything it can even be and five earth mass wire that traces out its orbit that the gravity gravitational consequences of that would still produce the signatures that we see in the distant kuiper belt that said as you as you mentioned to speculate if we kind of imagine that planet nine is one of the embryos involved in the planet formation process through which you build up uranus and neptune then we would indeed expect it to have a large icy mantle with a with a subdominant fraction of it being composed of rock here i need to give credit where it's due which is to a paper by isidoro andres adora on collaborators which came out before all this planet nine stuff was hot and this must have been 2015 or so the problem that andre and company were working on is actually formation of uranus and neptune and they had imagined that uranus and neptune formed from sort of collisions of few earth mass planetary embryos you know sort of say five earth mass objects now what they found is that in their calculations the accretion process was not a hundred percent efficient which of course is reasonable you should never expect the accretion process to be a hundred 100 efficient and in their case some of these embryos would get scattered out right and as they would get scattered out because the solar system would be in a cluster they went as far as to write in their paper that through this process one might expect there to be a five or so earth mass icy embryo hanging out at hundreds of au with a marginally eccentric orbit as this is just a natural consequence of building uranus and neptune so i think from as far as the different variants of the planet formation story go this one is uh is is the most likely for planet nine's genesis you say the word embryo as an as in this is some sort of primordial core of of maybe a failed gas giant something like that what would that tell us if we had such a thing i mean what would that reveal about the the origin of the planets in the solar system because i mean if you look at earth it's kind of hard to tell much because earth is always resurfacing itself and you know obviously mars did that venus do we have a chance of getting a glimpse of the early solar system from such an object right so i think that it goes even beyond that because suppose you know tomorrow we discover or by we i mean the the global we not necessarily us but somebody discovers planet nine the moment you know where it is on the sky you can interrogate it with a whole range of instruments with with things like a hubble telescope with with keck with whatever then you can study in as up close as it gets perhaps the most typical planetary mass object that exists in the galaxy as far as we know because after all what the last three decades have revealed to us and the search for exoplanets has demonstrated is that the most common outcome of planet formation is not jupiter or saturn as far as we can see it's not the earth right it's an object which is marginally smaller than neptune and marginally bigger than the earth namely sort of five earth masses that's a typical outcome of of planet formation that's if we find planet nine it will be the closest window that we'll have into into seeing what exoplanets really look like that's interesting now okay if planet nine is uh essentially super earth whatever its nature is terrestrial or non or whatever and it shows us you know basically the most common type of planet we see in the universe have we seen any exoplanet or star systems that have a planet an ejected planet that's way out there in a sort of the same position as planet nine would be yes we have in fact this was a relatively recent paper i i admit i forget the the license plate of this particular exoplanet but it is an exoplanet that basically occupies planet nine like orbit if i remember correctly i think it was hd 106 906 but i might be mistaken basically you know it's it's a thing that goes around its host star every 10 000 years and has a marginally eccentric orbit now there the we think we there's a pretty clear understanding of of how it got there and it basically follows this exact story that i mentioned just a few minutes ago you see the the host star in that system is a is a binary so the planet would have been scattered out by a binary and because like most stars this star would also formed in a birth cluster right the passing the effects of the passing stars as well as the cumulative sort of tidal gravitational effect of the cluster would have detached it from the binary and it would have parked on a planet at nine like orbit so it's it's interesting to see that this process that you know within the solar system mostly comes you know we mostly know about it through simulations indeed appears to to be active and work relatively well in the galaxy more broadly one question that's been popping up recently regarding planet nine is observational bias and that we might have maybe it's been suggested that maybe there's a bias and when we look at these objects that appear to have been perturbed by planet nine could you go into that and explain what that is and why it probably isn't yeah of course so you know to be clear this is the bias issue is not a new issue and it's not controversial in the sense that you know is there bias or is there not there absolutely is bias in any observational survey right that's that is a fact and even five years ago this was something uh this was a discussion that we were having with our colleagues you know the clustering that we see of the distant kuiper belt objects is it is it real now there are two ways to attack this question right one quest one way to attack this question of whether or not there's bias is to do what's called survey simulation where you say okay i know exactly where my surveys looked and i can simulate what they should have seen what we see is it consistent with their observational history or is it is it not right and doing the exercise this way for the distant solar system basically gets you to an inconclusive answer particularly this is because the two best characterized surveys which are the the asos and the des surveys are also the most biased and in the case of the des survey where the telescope was pointed in fact happens to align very very well with where the cluster is so the the basic answer to all of these analyses dating back to 2017 as well as well as one from 2020 and there's a new recent one by uh led by kevin napier and and company is that doing the exercise this way you can't tell you can't tell if the orbits are clustered you can't tell if they're uniform and that's not surprising this is because this individual surveys have only limited have only searched very limited part of the sky okay now the other way to do this exercise is to abandon the survey simulation approach and do what's called observability mapping observability mapping basically forgets about who discovered what right and just says let's look at the senses of discoveries on the sky of kuiper belt object a kuiper belt objects that are you know distant distant broadly defined meaning say semi-major x is greater than 50 au or 100 au if you do it this way you have actually a huge sample right you have something like a thousand points on the night sky that are pretty uniformly distributed across the sky and then you can ask the question if if you were to have a uniformly distributed set of very distant orbits right the ones that appear clustered would you be able to with the cumulative you know observational effort that is that led to the discovery of all of these objects would that effort have discovered this uniformly distributed population the answer there is it's pretty statistically significant what you get at the end of the day is that the false alarm probability for clustering is something like 0.2 percent okay so it's different ways of doing the exercise one is the you know survey simulation approach is one that would be better if this sample was was larger but of course the sample of well very well characterized kbos is not very large at all it's something like 14 objects so it kind of falls short of being definitive the observability mapping approach uh takes advantage of the large comparison sample and from that even though it's less ideal in some sense it can give you better uh statistical you know the inference power does that make sense it does now another thing that's come up is there have been a few suggestions that maybe it's not a planet and it's something else and the first question in this in this uh in this group is how about a group of objects as opposed to a single planet could there be sort of a cloud of objects collectively affecting objects in the outer solar system or would that simply have long ago collapsed into a planet yeah okay so as i mentioned maybe 10 or so minutes ago as far as the calculations go we cannot tell what planet 9 is and indeed replacing planet 9 with a you know gravitate with a gravitationally charged wire if you will a a wire of mass that traces out its elliptical orbit would give you the same dynamics mathematically that's true and we even make that approximation sometimes for the kind of analytic models that we have in our hierarchy of calculations the question then becomes is that astrophysically plausible so if you go to the route of saying planet nine is really not a planet it is a ring of material you are in invoking an a kind of a lopsided ring of material to explain why the distant kuiper belt is all is a less massive lopsided ring of material so so you kind of are back to the question of what keeps the coherence of this forcing 10 or so earth mass ring of material in a kind of structured uniformly eccentric way there are ideas out there you know for how to do this and uh you know this has been work uh done both by group of anne marie madigan at uh university of colorado and boulder as well as some group by jihad and collaborators and it's it's very very interesting and i think that you know there's a mathematical way to to replace planet nine with material with a ring of material i don't think it it makes very much sense from this sort of solar system you know formation point of view or or really the long-term evolution of the solar system but it but it's a it's a possibility that you cannot rule out a priori you cannot rule out you rule it out a priori you know you can only sort of rule it out based upon the existence of other patterns so you could end up with a planet nine turned out to be a lopsided ring of material being shepherded by planet 10 [Laughter] right right so i mean it's it's sort of that you know it's that mode of gravity what we call secular interactions which basically allows you to get away without knowing or specifying really even where planet nine is that allows for this analogy to work the way to think about it qualitatively is that along many many orbits right the kuiper belt objects will sample planet nine at every you know orbital position that it takes right so it's like kind of like taking a movie you know filming a movie of the outer solar system and then running it in on fast forward so that the orbits trace out the individual objects trace out little rings or little ellipses gravity turns out actually works like that wherein if you take the hamiltonian and average out the fast interacting terms you get to that description and when you get to that description it doesn't matter if it's a planet or or you know a thousand little test part or a thousand little dust particles that all str stretch out along its orbit it's a beautiful thing now the uh as far as the possibilities regarding planet nine the elephant in the room the primordial black hole hypothesis do you think that that's even really realistically possible look i have to once again you know invoke the fact that we we don't know anything about what planet nine is from the calculations right so the calculations again only tell us the mass only tell us the orbit are primordial black holes real in the first place now there is an expectation that black holes of a spectrum of masses should have been generated during the very early stages of the universe right so such a black hole would be you know a product not of the usual stellar evolution the way you make kind of normal black holes that are you know a couple solar masses plus so yeah there's an there's a kind of hypothesized route to make such objects are so you know do we expect such an ob do we expect their number density to be so high that we would expect one to be in our own backyard my understanding of the numbers is that it's kind of unlikely but of course with these types of questions there's a huge amount of room for turning knobs and uh and there's a huge amount of room for for air if you will and the cool thing about this is that the elephant in the room would be like the size of a baseball or something right so it'd be a pretty compact and pretty massive elephant but yeah while it's not again something that you can a priori say with infinite confidence does not exist i think a planet might just be a somewhat more somewhat more kind of you know basic explanation for for what we see still though you gotta one must admit having a small black hole in the outer solar system that would be one very interesting object to study up close you know it it sure would it would be really really cool the process the problem with that is if it's if it's indeed a primordial black hole we'll never find it you know what i mean like we'll at least even if we do find it it'll be long after i'm uh i'm dead and i'm planning to live a long time so you know it's one of these things that where it's hard enough to pin down a planet on on the night sky pinning down where a primordial black hole is on the night skies is getting into the impossible territory now capture dynamics in the outer solar system so it seems likely that that planet nine would be a member of our solar system having been born here but what about other kuiper belt objects is it possible to capture smaller objects now i know that there's you know we can sort of dynamics with jupiter and things like this allow us to capture interstellar objects and there are a couple candidates for that but what about the outer solar system is there even really a mechanism i mean could we capture some part of another star system's work cloud yeah so you know generically while you are in the in the disk sorry i'm sorry while you are in the cluster while the solar system is in its birth cluster there is an exchange of of material that's going on it is a little bit like a daycare center where the you know the germs indeed do not stay confined to a particular kid they they spread pretty well is there a mechanism for this yes you could imagine a mechanism in fact that involves jupiter so suppose some other star loses asteroids that's easy to do they get ejected by the planets on that star system then they are floating around then one gets close to our solar system and in fact hap uh you know starts um interacting with jupiter and and scatters off of jupiter now it's in a situation where it's got an elongated orbit which is tethered to the gravity of jupiter then if you then go back to the same process that we mentioned earlier and say okay you've got passing stars which can perturb it you can give it a little kick at aphelion from a passing star and you've circularized it now you've created a stable object with a large semi-major axis in orbit around the sun which came from elsewhere such a process is easy to imagine the question is how efficient is this production mechanism and the answer is not efficient at all now looking for planet nine we have a host of new instruments coming along soon actually quite a few big telescopes and then of course we've got the very reuben observatory and hopefully james webb what is the the instruments that you're looking for to try to get some time on to directly look for planet nine well i think that the here by far the the main kind of game changer is going to be vera rubin because their rubin with with pretty astonishing efficiency will scan the sky over and over and over again that's that's what we need to discover planet nine moreover it goes down pretty deep above 23rd magnitude that's that's good that nine might there's a there's a possibility that planet nine might be dimmer than that i i sure hope it isn't but but you know barring that possibility very reuben should have a pretty good chance of discovering planet nine even if not vera rubin will you know discover i i don't actually know the precise expected number but i think it's it's more than an order more than an order of magnitude more distant kuiper belt objects than we see at the moment so i think that's going to be really cool that's going to sort of refine the theoretical models further and it's going to be kind of the next generation no you know leap in mapping out the structure of the of the outer solar system this is not to say by the way that vera rubin will not have you know observational biases of its own it will just like any survey but i think that the sheer numbers of discoveries should overwhelm any uncertainties that come from that regarding very reuben or what also the lsst was what a large synaptic survey telescope that is going to basically automatically do the observations for you right so you'll just have to search through the data that it's collecting and and essentially look look for movement now i assume you'll do this in a computerized way i i doubt you'll be dusting off clyde townbau's blink comparator so you spend five years looking for the thing do you think you got a good chance once that that first light happens and research happens with uh vera rubin do you think you have a good chance of finding planet nine relatively quickly and straightforwardly yeah i think it's sort of uh you know the time scale that i imagine is is maybe you know years not certainly not decades i think it's you know about higher than months on the order of years and smaller than decades so yeah i'm really really excited about vera rubin coming online and you know one other cool thing is a lot of the data maybe all the data is is public from what i understand so it's it's going to be it's going to be quite a treasure trove i wonder if they could do citizen science with it in other words like they do with planet hunters or tests where you can actually in involve the public to actually look through and see you know if things move i wonder if they'll do that i haven't heard anything yeah i would be surprised if there isn't something that they do which involves the public i think you know one of the really phenomenal things about astronomy is there is a strong push for getting the public involved there's a strong push for for outreach so yeah i would be surprised that that wasn't part of the story especially because you know the general public really resonates with with the solar system just like just like we we do as kind of professional scientists so i think that i would assign sort of a high likelihood to that being something one could get involved in as a as a citizen scientist if they wanted to now you recently did a collaboration with a miami symphony was it uh tell us about that music and planet nine yeah so this was a this was something that started i guess back in 2018 and you know this this came out of a friendship with the conductor of the miami symphony eduardo marturet who is a you know i mean people like to throw around the word genius like oh somebody's a genius somebody is uh you know genius for this for that i mean the guy's really truly a musical genius and i don't mean this in like the kanye way right he doesn't go around announcing that he's one but but having worked with him it truly is phenomenal to see how he writes music so he got inspired by the planet nine hypothesis to extend the planets the planet's suite to include a planet nine symphony and i was of course very very excited about this but uh you know it was a it was a true kind of humbling moment where he said okay i wrote thing uh the lead part is the guitar part and you should play it and so you know i must admit it was uh it was one of the coolest things i've ever done it was also super hard to play because part parts of the uh the guitar part are well as you say they're they're more complex than the uh than the music that you know we play with our with our punk band so you know it was really a learning experience and i had a tremendous amount of fun doing it but we just recently completed the recording of it and there's a video on youtube where you know it's the symphony playing and me playing in la we recorded it asynchronously and the final product was sent to the international space station just about you know three weeks ago where i assume with the high likelihood that that they must have blasted it in the you know in the space station i wouldn't see why they wouldn't so yeah it was a really really out of this world and cool experience tell us uh tell us about your punk band uh do you like write songs about the solar system other than planet nine you know we write songs but none of them are about the solar system i mean there's there's exactly zero overlap in content between between the solar system or or really anything astrophysical and the in the content of music that we play that said everybody in the band is is involved with astronomy so i play you know guitar and i sing and eric petigura who's a professor of astronomy and astrophysics at ucla is on guitar john zinc is also an astronomer on the drums uh you know in the really in the last i don't know five years or so in the in the kind of overall rotating lineup of the band between you know chris rollins on the bass and chris spalding on guitar and gabrielle uh pikiri on on the bass like there wasn't anybody who wasn't somehow involved with with something in the physical sciences now the band's name is the seventh season right that's right yeah it is music to some ears music to some ears all right constantine it's always a pleasure to talk to you and i wish you well in searching for planet nine and above and beyond a primordial black hole it would be absolutely amazing if it was a five earth mass frozen burrito absolutely absolutely thanks john for having me on it's always a pleasure to discuss with you yep and we'll do it again next time something comes up and there also i should point out will be links to the musical performance the new paper etc in the description below for everybody yeah thanks again thanks for listening i am futurist and science fiction author wrong channel no it's not thanks for listening i am futurist and science fiction author john michael gautier currently hosting event horizon and wondering where anna actually came from one day i had a tablet computer the next i had a boss very disturbing and be sure and that's enough of that youtuber forever like subscribe and hit the bell sell out what [Music] you

Channel: Event Horizon

Views: 245,824

Rating: 4.8766727 out of 5

Keywords: planet nine, universe, astronomy, mystery, nibiru, sitchin, exoplanet, oort, kuiper, 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 2021, planet 9 orbit, planet 9 discovery, where is planet x, planet x, does planet x exist?, mike brown, alien, does planet nine exist?, breaking news planet nine

Id: 39y6Oqo6p18

Length: 35min 47sec (2147 seconds)

Published: Thu Apr 15 2021