The giant wave of gas discovered near the Sun in the Milky Way | The Radcliffe Wave

so all weekly 235th American Astronomical Society meeting has been happening in Honolulu Hawaii remind me why I didn't sign up meeting again and as with all meetings of this kind announcements of new results and discoveries have been pouring in and it's like only halfway through as well so one of my favorites so far from the meeting has been the announcement of a discovery of a giant wave of gas running through the Milky Way which it turned out the Sun in solar system are also interacting with so our local backyard of the Milky Way like the local sort of solar neighborhood around the Sun is really where the foundations of a lot of Astrophysical knowledge founded so everything from you know how planets form around stars from observing our own solar system - you know how stars form from these giant big nebula of gas like the Orion Nebula - to supernovae which produce more nebulae which stars then form from and planets form from as well but then also you know the movement of the Milky Way itself how stars come together on spiral arms and then all move around the center of the Milky Way together and underpinning all of those things all of those processes I've just described is gas was I talking to her about gas gas is what makes up those huge giant clouds of nebula it's what stars form from it's what stars give out when they die it's also what binds all the stars together and makes the spiral structure that we're so familiar with thing and other galaxies and also now know that our Milky Way also has that structure as well so in order to understand what we see around us we need to understand gas now the problem is gas isn't a solid kind of is in the name it's a bit of a clue but it also means that gas is very difficult to observe because well it's gases gas around us all right now right in the air and we can't see it and so it means it's very difficult to determine not only the absolute size of the cloud of gas because like where actually is the edge of it as you know when it's illuminated and it's got dust in it you can kind of see it from the light from the surrounding stars but it could be going much further than that and we might not know but then also like the distance to these clouds as well it because you know a solid object is all moving together so all of the light from a single object is either blue shifted or red shifted either the wave length of the light is squashed or it is stretched by the fact that the whole thing is moving the same way that the sound wave from a siren going past you from a police car now mimics fire engine whatever it might be is squashed as it comes towards you and stretched as it goes away from you and and that's when you hear that the difference should have change in pitch as the siren screams towards it away from you in a gaseous object though all the molecules are just moving however they want to move they're all moving in different directions the idea of a gaseous object is that the temperature of the object means that the molecules are moving much faster the hotter the gas is and so they're also all moving in random directions it's also you don't get a single sort of redshift from that object so that's very difficult to determine the distance to it how we would usually also because they're not really sort of single objects we can't use the tricks that we do to determine distances to stars like parallax so this is the idea of like perspective of whatever angle you're observing the star are you observing it like in June from what angle are you observing it in December when the earth has gone all the way around the Sun you're observing it from a different angle and review seen its position shift because of your perspective because it's not all one single solid object that you can point at me like that is the cloud of gas in that specific part of the sky edge it's very difficult to do it that way as well and so in the past because we've not been sure of the size of these things and listen to these things we haven't really been sure how they all relate to each other and crucially how they all interconnect so the accuracy of the distance we had to the big clouds that permeate all of this interstellar space in the Milky Way was actually about as accurate as the size of the cloud themselves which you know for astronomers terms that's probably an order of magnitude at least but it's not great if you want to actually look at the detailed structure of the Milky Way at least in our own solar neighborhood where we have a chance of doing this so the way we've done this before is we've used the dust that hangs out in these gas clouds as well to try and determine how much the Stars behind it compared to the stars in front of it which aren't affected by the dust reddened by absorption so it absorbs a lot of the blue light and you end up only really getting red light through because it's longer wavelength so it can kind of go like around all of the dust particles then you can kind of make a sort of model what's going on which stars are getting red and in what area and so how much cloud would you expect to be there and and at what distance based on the distance of the stars that you know are getting reddened and not getting redden so based on all that prior knowledge our previous v4 what the towered stolen neighborhood looked like was what was called gold's belt so literally like an arc or a ring of gas clouds that connected sort of the Sun with the surrounding regions like Orion Nebula things like that in a big arc because you saw it sort of as an arc on the sky and therefore if you think about how they're then sort of projected into 3d from like the 2d and what you see in the sky based on the rough distances we did have it was sort of making an arc kind of shape so it's called Gould belt but a recent mission called the Gaia mission which has been launched by ISA the European Space Agency is changing all of that so what Gaia is doing is getting very accurate positions for a billion stars in the Milky Way so it's doing that by getting really accurate parallax's this perspective change on them and what it's measuring is not just the sort of X Y Z position of the stars but it's also measuring the velocity in the x y&z directions as well so we can get a really detailed not just map but also how the Milky Way is also moving now combine that with much more detailed statistical modeling of what is going on in these clouds in terms of the reddening of the stars behind it which you now know the positions much more accurately for as well and then also some really interesting statistical inference what you would get is much more accurate positions of these clouds in comparison to the stars as well and so this is exactly what happened last year in july 2019 Catherines our current collaborators produce this wonderful resource that was open for anybody to use of super accurate distances to the nearest what we call giant molecular clouds of gas in our local Milky Way and it was essentially this huge big giant long table of all of the positions and sizes of our sort of local neighborhood gas clouds and the uncertainties have been roll down our like 5% of the size of the card rather than the entire size over the cloud and so this was unprecedented the level of detail we now had in terms of where these cards were what size they were that was great but big long tables are not exactly great for the human brain it's not something that we can process easily plus we're dealing with astronomy here literally the science of observation and imagery that is done in 2d but really is in 3d so what the team really wanted to do was visualize what was going on here that's easier said than done though to do that you need a scientific visualization tool that allows you to actually plot something in 3d not just take something that's 3d and look what it looks like in the XY plane and the Y Zed plane in the XZ plane you actually need to be able to plot it in 3d and really get your hands on it and spin it around and look what it looks like from every single angle and also look what it looks like in comparison to other data sets to the positions of other things in the position of where we think the spiral arm is in the Milky Way and where the Sun is and where gold belt previously was thought to be etc and that tool you can't take it for granted that that exists it sounds like it should exist it's 2020 you think you'd just be able to walk down to the shop and just take a 3d of is tool but the thing is that kind of tool to put in all that data is a very specialized taunton so to do this you have to find people who specialize in this 3d visualization of astronomical data this so this is what three astronomers set out to do Catherine Zucker who is the lead author on that paper calculating the really accurate distances drow Alves who is an expert in star formation and the sort of local backyard of the Milky Way and Alyssa Goodman who done work with Roy Albers before because she was also really interested in our sort of stellar backyard interstellar space but also had been working with people to develop these visualization tools for a long time and specifically one called glue and so by working together what they were able to do is actually work on seeing what the structure of these gas clouds looked like for the first time what they found was unprecedented it wasn't a ring or an arc like what girls felt had predicted it was a wave an actual 3d wave spanning about nine thousand light years and going sort of up and down out of the flat disk of the Milky Way by about five hundred light years running right next to the Sun as well and it was amazing how well a mathematical sine wave actually fit this data as well it wasn't like it was sort of a random wave it was really a beautiful what we call a damped sine wave so Catherine suckers Wow Alvarez and Alyssa Goodman all work together with a couple of other collaborators to be able to publish this result in nature this week the first issue of 2020 announced with the American Astronomical Society meeting as well and what I love about this discovery is that yes okay it was the combination of many years of work but it also was one of those science-u rica moments that you you don't really hear about that often and so because these three are also my collaborators i sat down on video chat with them on a zoom meeting in order to be able to have them tell you their story themselves so I sat down with drow who's in Europe and Alisa and Katherine here in America for a group chat one day and this is them telling me the exact moment when they figured out that what they found was unprecedented so it all started when I moved for a year on this wonderful program which is the Radcliffe program and to work on data from Gaia the satellite and I don't think back then we knew what we were getting into we have an idea which was to explore the local neighborhood and in October was a month I was there I was this is but life to start this this is mostly about how collaboration works and our wonderful people can make wonderful things together actually and once you go to a talk in October this was October last year and I remember being in a flight and no talk and have to present the talk today night the next day in Paris and I remember thinking this image is that the group of sick by now at this movie that was stuck in my head when I played back and forth back and forth it was a hint of a connection between two molecular clouds giant Lego clouds and that's kind of like if I have to put the seed to do to the project is exactly that movie where he kind of led us to say well is that connected it's not connected so this was Paris in October back then we start calling it the ramp because was a cloud that was below the plane and other clouds on the plane it was you know maybe there's a ramp for whatever reason of gas going from the plane to a nice kaiser ioan that's how we started and it was kind of interesting the first reaction of when we get to talk that no one really believed it by the way I did not think this ramp idea was real I thought it was just as grandiose ideas I was graceful it was great because you you were also the first one actually the hard work of connecting the dots in with the data and that made all the difference because once once Catherine did this it was in Paris for me and by the end of the meeting I thought there is clearly something probably no one did but I was pretty convinced there was something yeah and and so she kept trying to fill into pieces and eventually she found something let her explain yeah so I was talking about this ramp that ended up being something like only one twentieth or one fifteenth and being tax away you can see at least a half of it from the beginning and so what first thing that we did was we tried to connect these two clouds that allows that within this ramp out all these major star forming regions we mapped out all the structure in between them and which had never really been studied before in 3d in 3d ever and so now is we actually took these two next scene ramp clouds and we filled in all of us really and sometimes we fit perfectly in 3d too it was entirely insane I was grading outside Jos office and I said well I did not believe you're right this is and that was only like even even when Katherine did that you know it was what was that like a quarter a third of what we have now it's like less than less than a tenth okay so it was a linear structure and so I kept keeping track of what they were doing and I kept getting these little news flashes and and then one day she while calls me and it was I think a Friday evening and we both had had social plans canceled our families were out with other people and he says he says he was at Radcliffe which is like three quarters of a mile from my office here and he called me says um you busy and I said why he said I can show you something I said my office and so so we decided to order some Indian food and get some dinner in my office because like both of us don't get that much chance to actually just sit around and do science and so and we call up Kathy because like this isn't there and she lives around the corner and so Pat then we say like Oh any Indian food you wanna come over yeah yeah so we're all sitting here at this very table we we put what you I wanted to show me which was a bit more of this series of clouds in 3d all together in in this software that we used a lot called glue to to organize data and to see it in 3d and and then she while we're Katherine I can remember says oh yeah like I wish we could just see this in in a cartoon of the galaxy because clearly this is some long 3d objects and it bent from the side even though I'm involved with both of these software projects I had forgotten that you could open data in world wide telescope which is this program that can contextualized other army data inside of glue so we just dragged the data onto the canvas of glue and we select world wide telescope and and all of us just go what okay because the data exactly in the cartoon model that Robert hurt and other experts about the Milky Way had made and they put this kind of dark very straight lane that didn't look exactly like exactly where this reckless we have and it was just super weird um and and we thought oh my god and so we were already like kind of drooling Indian food taxes in the winter we only saw a part of it but then what happened was I guess I can turn into a we're fully convinced and I was convinced but I wasn't convinced that we had enough for the paper to say well we didn't just cherry-pick this nice straight line right and so then Katherine took it upon herself to find a distance to every known molecular cloud you know within what was it to kill but imagine right that you just took everything that's now in this wave structure that you can see in the video and just scrambled it like with an uncertainty of 30 or 40 hmm there's no way that you see that and so it's really these really sophisticated statistical techniques that don't think miners group have been working on for a decade you know Katherine's work to actually refine those and then the idea of adding in Gaia which of course was very independently from the colors of stars which before um anyway and so it's sort of like like she I said it's all about collaboration and like everything came together right at this moment and now it's just too easy to see the 3d structure of these things and so you know now we want to look at more of the galaxy and I mean I that's what I really really enjoyed about this part of this collaboration was was you know bouncing ideas having Indian food and coming up with crazy scenarios for the whole thing just hearing that story it gives me goose pimples like what they they turned what was thought to be an arc into this long straight thing that undulates containing something like three million times the mass of the Sun in gas that connects all of those stars in our region of the Milky Way it's hard to wrap your head around and no one can really explain why this even exists yeah like what actually caused this wave is it sort of like a ripple on the surface of a pond did a globular cluster like a big cluster of stars or did a sort of dwarf galaxy that was orbiting the Milky Way crashed through the Milky Way's disk and did the ripples shouldn't that encounter so spread out through the gas and and that's what's giving us this shape no one really knows yet could be something else entirely it could be a supernova in the disk of the Milky Way that was incredibly powerful maybe it was the merging of two black holes and perhaps the shockwaves from that have caused this wave we're not entirely sure like people are thinking at various different ideas all the time and what I love is that because this is something that hasn't ever really been considered by observers or theorists or people who simulate galaxies in the universe as a whole either before they're gonna get everybody together there's literally gonna be this wave card in the summer of this year where they get everyone who's an expert in star formation and gas in the Milky Way and kinematics and dynamics of how things move in space together whether they are an observer who used telescopes or whether there are theorists who stones at the blackboard or whether they are a simulations person who uses computers to figure out what's going on they're gonna literally like everyone in a room for a week to try and figure out what's going on and I am just like I volunteer as tribute because that is like an Astrophysical whodunit and I want to be there obviously when you get something like this published it is amazing but always the next question is what comes next what in the future for this kind of work and so I asked the team that when I chatted to them as well attention right now of course we want to do a lot of things about you know it's a wave is it oscillating and how does it oscillate and all that why does he oscillating but there's one thing that I think it's very interesting is that we just crossed it 30 million years ago the Sun we just essentially we're coming from Orion 30 million years ago solar system crossed minefield which was all the massive star formation in Orion to all the blouse groups can also seem to see the naked eye actually and that must be kind of something it must have left some mark on the planet this aspect of you know we are related to the Ratcliffe way if it's not them something far away probably something you can find when your mass spectrometers get better and better as they are getting better and better you find this iron 60 everywhere on the surface of the planet that can only come from supernova so it's not that aspect for me is fascinating it's not something that it's over there and me here know it's kind of part of us why because then we're going to cross it again because of way in orbit who's working the galaxy we have this intertwine Minh will be crossing the well not the wave because the gas will be gone but all the young stars that was our force wave will be our you know neighbors for for the next orbit we really know where that came from and so this comp reposed and Catherine and I Radcliffe is to bring together all the theorists who have all kinds of ideas about what could be causing the wave and so it's everything from you know stuff dropping in from outside the galaxy and causing a perturbation there's some people who think it could be you know some kind of feedback like really crazy explosions from stars I don't think so but you know some people who think that like globs of dark matter and the disk in the Milky Way I also don't think that you know I think it's probably some kind of collision but an answer to your question um this one is the one like joe said you know right up next to our face and so it's the easiest one to find and so it actually in fact might be easier to see little ripples in edge-on disks of other galaxies when we have oh cool then to find more in our galaxy but of course we'll try that's my kind of area as well right so maybe I love the idea that the next place we could find something like this isn't necessarily in the Milky Way but it's in those galaxies that we can see them edge on you know we don't see them face on with that beautiful spiral we see the edge of them like sort of looking at the edge of a pitcher bread kind of thing and we might be able to see the dynamics of the gas in those before we spot it anywhere closer to us in the Milky Way and that's the kind of thing that I do I care about other galaxies in the universe and yes mostly what their black holes are doing to them but also you have to understand what's going on in the rest of the galaxy to figure out what the black hole is responsible for so I do a lot of this sort of study of what's going on in the disk of galaxies in the plane of galaxies and it's kind of awesome to think that something that someone was doing so removed from my work so close to us in the Milky Way could eventually link to what I'm doing you know trying to understand the galaxies billions of light-years away so maybe I will get an invite to that meeting after all who knows fingers crossed if I can even go we'll see but if I do go then know that you will also be a fly on the wall for that meeting because there is no way that I am letting you guys miss out on the Astrophysical whodunit of the decades is it too early to say about I don't know let's go in there the Astrophysical whodunnit of the decade why didn't I sign up to it that mean you know ye seriously what is wrong with me when do I the next one is maybe I can go that one please be somewhere tropical please miss Wilma tropical Madison Wisconsin nope sorry Wisconsin I'm sure very pretty but you're not Honolulu are you it was the end of the decade but the start of an egg shape as long there and then you can kind of make a little bit of a model for what's going on and which stars a resident rezoned why am I always in when I'm filming like before Christmas it was a pre-christmas cold and now it's the like post-christmas cold that I still can't shake and I still felt like I'm like mud stickies you

Channel: Dr. Becky

Views: 101,833

Rating: 4.8964243 out of 5

Keywords: Dr becky, Milky Way, galaxy, giant molecular clouds, gas clouds, interstellar space, dust, gas, Radcliffe wave, Becky Smethurst, Rebecca Smethurst, astrophysics, physics, astronomy, space, science, technology, radwave, radcliffe wave, the radcliffe wave, harvard, radcliffe, largest structure in the galaxy, biggest thing in milky way, gould belt, benjamin gould, 2020 discovery, new space discovery, galactic wave, galactic ripple, milky way wave

Id: VJLl0gaMlGE

Length: 25min 11sec (1511 seconds)

Published: Tue Jan 07 2020