Hubble’s legacy: A journey into the Universe | The Royal Society

hello and good evening everyone and welcome to this evening's event hubble's legacy a journey into the universe part of a series of events that's running around the royal society's 2021 summer science program yes ladies and gentlemen it may feel like winter to you but we are still celebrating summer here at the royal society now um the event tonight explores just one of the fascinating themes that featured in this year's digital showcase and we're going to be looking at how the hubble space telescope has really changed our view of the universe and we're also going to be getting ultra excited about a new telescope called the james webb space telescope um i'm really excited because we have an excellent panel joining us for tonight's um discussion but we also want to hear from you the audience and we're going to be using an online web page called slido.com and what i'd like to do now is invite you to open slido.com and you should see a little box where you can put in a code now our magic code for this evening is h2411 i'll repeat that again h2411 enter that code and you'll be able to join in the discussions you can add your questions uh you can upvote other people's questions if you really want to see that question answered um and i'll be monitoring your questions tonight and trying to put as many of them to our panel as possible um and we're also going to be conducting some polls uh so please join in on slido.com so you can take part in our polls this evening um now for any of you who are looking for live captioning this evening we will be providing that and you can click on the subtitles closed caption button in the bottom bar and uh for people on the twitter sphere um you can use the hashtag summerscience not winter science my name is professor catherine hayemanns i am the astronomer royal for scotland and it is a great honor for me tonight to join an amazing panel of people we have jim dunlop from the university of edinburgh jillian wright from the uk astronomy technology center astronaut jeff hoffman and also professor at mit boston us and we also have steve wilkins from the university of sussex and what i'm going to do now is i'm going to invite each of my panelists to introduce themselves and to tell me what they think the most exciting discovery is that hubble has made so let's start off with jim thanks catherine i'm jim dunlop hello everyone one exciting discovery well this is my bias i study early galaxy and black hole evolution and i would say one of its most surprising and exciting discoveries is how early in the universe structure formed from the originally rather structureless big bang so how early galaxies and stars formed nobody before hubble thought it would be when it is and we'll probably discuss this more later thank you professor didn't unlock uh professor jillian wright so i i think what's one of the really exciting things hubble's done is some of the more recent work that it's been doing on exoplanets and the way it's shown in the way and how how you can study and understand what planets that are orbit orbiting around other stars are made of and i think that's been very exciting wonderful thank you professor jillian wright uh professor and astronaut jeff hoffman yeah um and i should say i i did start life as an astronomer so actually to have been able to as an astronomer and astronaut put my hands on hubble and fix it was a great thrill um i have i i guess i would say the discovery that the expansion of the universe contrary to all prior expectations is actually accelerating rather than decelerating which ultimately then led through with other satellites and a lot of theoretical interpretation to the realization that the universe that we know and sense is only about four percent of the content of the universe and 96 of the universe we don't have a clue what it is that's pretty upsetting very humbling exciting maybe as well thank you very much professor jeff hoffman and last but not least um dr steve wilkins who is actually the reason why we're here this evening because he was the first person who uh suggested to the royal society that we have this theme in the summer science and steve most exciting discovery from hubble in your opinion thanks catherine unfortunately i think you all have stolen the three ones that i was going to mention so i think i'm just going to expand upon jillian's and say that this this most recent work on exoplanets it's even more amazing when you consider the fact that when hubble was launched we didn't know of any planets outside our own solar system so the fact that now hubble 30 years later is now actually studying those planets that have been discovered since hubble has been launched just makes it all the more amazing but at the same time i will work on a very similar field to jim uh so obviously finding the very earliest galaxy in the universe has been terribly exciting for me and something i've been involved in for my entire career in the field wonderful ladies and gentlemen i'm sure you'll agree that this is going to be a fantastic discussion this evening and let's kick start it off with a poll on slido so hopefully most of you have found slido now if uh if not please go to it because our first poll is asking you what are you curious to explore in the universe so please type in what you're curious to explore in the universe and the magic code game is h2411 and uh whilst you're typing in uh those uh suggestions um i'm going to turn to jeff because as jeff said in his brief introduction uh he is one of the lucky people who have actually touched the hubble space telescope in space now jeff was telling me uh beforehand before we logged on that he has spent 1 200 hours in space jeff i am one of your biggest fans because in one of your five missions you went and fixed the hubble space telescope and i personally wouldn't have been able to do any of my research without it and the same with all of our other panelists this evening so please can you can you tell us a little bit about what was that journey into space like um when you were going up to fixed hubble what was it like to have the whole astronomy community nervously watching when you went up and and repaired uh hubble way back when there were actually two communities who were very much involved and and actually one of one of the the joys of of working on the hubble was it brought together the world of human space flight with you know basically robotic astronomy science um two worlds which sometimes have been in some kind of conflict so there was tremendous yeah i mean i was i i kept getting calls from old astronaut friends of mine uh you know people i had been to graduate school with uh when they saw how complex our mission was going to be and how many different things we had to do you know they would have jeff can can you guys really do this uh and and um we didn't know i mean there were a lot of people who thought that nasa had bitten off more than than it could chew so to speak it was certainly the the most complex shuttle mission with spacewalks we had five spacewalks that had never been done before but also for the future of human spaceflight just as a reminder this was the time the early 90s when nasa was trying to get the u.s congress to approve money for the initial studies and construction of what eventually would be the international space station nasa was not real popular at congress given the hubble fiasco and and when we were training up at the goddard center at one point we got called into the office of the nasa administrator don dan golden who looked at us across his desk and said guys i hope you realize that the future of nasa's human space flight program depends on the success of your mission so yeah no no stress no no but we were well prepared uh all of nasa i mean it was an incredible working on it because everything that we could think of that would reduce the risk of failure on normal missions maybe people would have said no that's too much it's too late we can't make this change but this was hubble and whatever it took that's got done and and the results showed that we we did it right did such an amazing job now now jim i'm going to pull you in here uh we've got a question from tom that's uh saying what is the furthest object that hubble has seen and i'm going to tie that to another question what's what's the most exciting thing that you were able to do thanks to jeff and his team repairing hubble and i think it might be linked to tom's question yeah okay so good question i would preview it by saying that astronomers are not masochists we don't look far away for the sake of it okay so when you look a long way away there's not much light coming from the objects the objects are tiny the objects are blurry so the reason that people like myself and steve to a large extent study very distant objects is not because we care about the distance we're trying to look back in time okay so astronomy is very unusual unique in science that you can actually have a time machine and so i won't tell you how many meters the furthest galaxy we've seen is away but basically we've seen more than 90 percent of the age of the universe so we've seen galaxies within the first billion years of cosmic time and the universe is now known to be just under 14 billion years old and that was only really possible with the final refit of hubble which took place in 2009 when uh and i don't know if jeff was involved in that mission it might be the earlier ones but the the final refit put in a camera that for the first time allowed hubble to see into the near infrared it was called whitefield camera 3 and seeing into the near infrared allowed us to see more distant objects because the most distant objects due to the expansion of the universe have all the light shifted into the red bands redwood of what you can see and so one of the remarkable things i think about hubble is it's been going for 30 years and actually until james webb launches it's still the state of the art machine for the science that we are trying to do and for a space mission that is really incredible so you know we were involved in optical the deepest optical imaging but in 2012 with this new camera we took what is still the deepest of the image of the of the sky and near-infrared wave bands and that allowed us to see within about half a billion years of the big bang and we'll come to it later that's as far as hubble can see because it's a warm telescope relatively orbiting close to the earth and james webb will be colder and we'll see even further to the red and therefore we really should see when the first thousand galaxies formed so i'm not going to give you a distance in miles i'm going to say we've seen back over 13 billion years over 90 percent of the history of the universe catherine could i just make a quick comment uh you asked about the wiff pick 3. i installed with pic2 on the first servicing mission which extended into the ultraviolet and then they removed my beautiful with pictures which is even better but that's only a good cause jeff the fact that that hubble after 30 years is still state of the art that shows the value of servicing you know most people think of servicing yeah it was broken and you're able to fix it but the real value of servicing is that you know detector technology continues to improve like you know moore's law and and instead of just launching something and and and what you launch is what you have for the rest of its life hubble has been kept up to date and and it's now it was launched with 1970s technology yeah detectives and now it's a 21st century instrument as you say it's a great advert for sustainability it lasts a lot longer than any washing machine i've ever had we've got a question that people are recognizing that we're talking about the hubble's quite old now um and we're going to move on to talking about its uh its successor soon but liz is asking what's going to happen to hubble um once it's been decommissioned and no longer used for data gathering i don't know steve do you want to take that one so it's difficult to know because basically a decision hasn't been firmly made yet so over time with no further servicing missions bits of hubble may break it's entirely possible that hubble could catastrophically break we could lose contact with it in which case its future is a little bit more bleak in that it will eventually crash into the earth in a in an uncontrolled way but the hope is that's not gonna happen i think the hope is that we're gonna be able to continue using hubble for for several more years because although the james webb space telescope is is in one way a successor hubble has unique capabilities that web doesn't have so jeff was just mentioning hubble's ability to look into the uv now the new camera that jim mentioned can also look into the new visa into the uv and this is capabilities that that web won't have so i think we all hope that hubble will continue going but when it does reach the end of its life when things stop working um for safety sake it will probably have to be deorbited so it'll probably have to be um controlled back into the earth's atmosphere so we might see it one one day i think i think several years ago people talked about going to rescue hubble and bring it back and put it into a museum but i imagine the costs of such a mission were prohibitive as cool as it would have been jeff we're going to need to send you it would have taken it would have taken the shuttle to do that we don't have the shuttle anymore but the last servicing mission did attach a a a a adapter ring on the the bottom of the telescope so that someday hubble has no propulsion of its own so someday we'll have to send up a robotic spacecraft to deorbit hubble safely because you know you mentioned an uncontrolled d orbit that that would be dangerous because hubble will not all burn up some of hubble will crash to the ground so it has to be given a a safety orbit so um jillian i'm going to invite you now to come in and let's dissect the pole together um so um thank you to everyone on slido for putting in your answers to the poll which was what are you curious to explore in the universe so can we see the answers now for this poll can i see them here we go so we can see jillian what would you have put in this pole what would i have put in it i think i would certainly put black holes in it and i would certainly have put exoplanets in it um and so i think i think you know the things that are big here are showing up large the one that is of course curious is dark matter but but for me i think the questions around dark energy and the whole fact that the expansion of the universe is speeding up those those are maybe a bit more exciting for me personally than than dark matter um but there's lots of other things there the life the life of stars yes and understanding how stars form and die and how stars make planets or how planets form around stars i think i think that's an incredibly exciting area to explore brilliant thanks julian um so uh thank you for everyone for putting in uh your answers to that poll we've got another poll for you now this one's a quick one for you to answer if given the chance would you go to space and um and jeff i'm naturally going to come to you again on on this one now today i got ultra excited because nasa launched their dark mission which is going to crash into this asteroid the first planetary defense test and i kind of looked back to my childhood that armageddon movie and it was bruce willis who was going to go and do that so now we've got this amazing automated um um space telescopes and things like that you know is is the time of the astronaut past do we need astronauts in the future um you know you were critical in going up and um and servicing um hubble but is is there a future for astronaut astronauts in servicing missions and and undertaking these missions or will it all be robotic well uh when you know there's there's two parts to that answer the first is you know the utility of humans uh when you get and you know where there's big push now going towards the moon set up um exploration systems maybe mining when you when you get a system that's complex enough electromechanical computers and all like things break um this happens on earth it it happens up there and and you know if if we really had robots like r2d2 that were intelligent and could do things with their fingers and really thick you know we'd be living in a different universe okay uh i love space robots you know we're operating a robot on on mars but i know how much more we could do and how much quicker we could do it if we had humans working with those robots um we're getting only a fraction of the utility of the these incredible curiosity and perseverance rovers because we have to operate them so slowly and so conservatively because if they break there's nobody there to fix them if they get stuck in the sand there's nobody there to dig it out um and and so on if if we only had a few people there we we could double or triple the amount of science that we could get back from these incredible machines that's the first part the second part there's a lot of people who want to go into space and they're not going to be satisfied just to say oh yeah we can send robots no they're i want to go myself and we're just on the brink of that revolution where pretty soon there's going to be more you know tourists who have gone to space than professional astronauts i think that's great because the you know the innovation that's come out of all of the private space flight companies has just been astounding and and it's really pushed the state of the art in a way that wouldn't have been if if it had just been the same old nasa doing the same thing with the the big aerospace companies so i'm i'm very keen on more people going into space and there will be plenty of work to do julian would you go into space if you could all right well i always thought that i would i was always kind of you would watch astronauts in total law and think wow amazing to be able to do that i don't know that i would go now though because i've had a lot of fun exploring the universe in other ways well i am looking to the answer the poll and there is a definite yes feeling in the audience that about 94 would go into space so thank you so much now we've talked a little bit about hubble and and all of the exciting science we can do it but all eyes are now on the successor to hubble the james webb space telescope so uh 25 years in the making 10 billion us dollars it is the ultimate christmas present for any astronomer in your life um i'm very delighted uh that jillian wright is with us this evening because she uh led the part of the european team that built one of the cameras that is on the james webb space telescope so julian can you uh tell us what the james webb space telescope is going to be what what is it going to allow us to do we've got a question from jay what what's going to be the advantage of web over hubble um tell us all about it oh well i think so we've already touched on on one of the big advantages of web over hubble is that if we're trying to see the first stars and galaxies that have ever formed we know that hubble isn't quite big enough and we know it isn't quite infrared enough so one of the reasons that we really needed a large infrared optimized telescope is in fact to do the the science that so excites stephen jim but if you have a telescope like that you can do lots of other amazing things with it so one of the things we know is that stars and planets form in very dusty regions but it's very hard to see into those regions and actually look at the dynamics of what's happening and the chemistry of what's happening and try and understand how it's happening and because we have a large infrared telescope we'll be able to do that with web i think it's important for the for the non-technical part of the audience to explain the reason why we keep talking about the infrared it's not that the early galaxies and stars were just giving out infrared light i mean they were giving out visible ultraviolet light but because of the expansion of the universe that light is red-shifted into the infrared so we need an infrared telescope to detect those objects now one of the challenges of infrared observations is keeping things cool and when i've heard you talk before about this you've talked about your special magic fridge do you want to tell us more about this fridge that you're about to launch in space it's exactly that it's a fridge and instead of um using any type of cooler it works exactly like your fridge so it takes helium gas and it circulates it and it expands it and then it compresses it and that little but it's tiny and it operates at very very cold temperatures so what our fridge does is it makes us 33 degrees colder than all of the rest of jwst and the reason we need to do that is because in the infrared we think you could think of infrared as meaning heat so if your instrument isn't very very cold colder than the things you're trying to look at then instead of seeing a beautiful exoplanet in the mid infrared what you would see is the mid infrared that's coming from my own detectors and you wouldn't learn anything so we have to be very very cold um now steve earlier when we were chatting you asked jillian what the the aspect of the launch of jj she was most worried about so i'm going to turn the question back on you steve what gives you the most terror at night about this uh amazing instrument that's about to be i think i think the the entire process all the way from launch and then um so once once web is launched that's only the first stage then web as people may have seen the videos online it's actually got to unfold so it deploys on its way to its its um its final location and then that's not the end of it even if it's done all those deployments we need to slowly turn on each of the cameras this is where jillian's fridge is gonna start working as well it's gonna cool down the cameras and it's all of these different things so it it would be fine if if it launched and that was the end of it that we knew it was gonna work then but we've actually got about six months of sleepless nights ahead of us coming soon um and i think actually the most terrified aspect of this is that there is six months where something could go wrong in those six months and it's such a long period of time um yeah i imagine the engineers and people like jillian who have been really hands-on with the telescope will be even more worried than i am as somebody who's just going to be using it but yeah it's it's all terrifying now jeff we've got a question here if if if it doesn't quite work as as steve is worried about will you jeff go and fix it for us this time round is that possible can we service web just like we serviced hubble well as finding an an astronaut who would be willing to go and fix it sure i would volunteer in a second i'm i'm sure there's a lot of the younger ass active astronauts who would as well unfortunately uh first of all we don't have uh the spacecraft kind of equipment that we would need to mount a major servicing mission i mean the the shuttle was great it it was a a platform for doing space walks we could carry lots of extra equipment uh tiny little space capsules we we don't have that much less being able to go a million miles million and a half miles away to where hubble uh where webb is located but the the second thing is webb specifically was not designed to be serviced um whether or not that is the correct decision history will tell but um you know web was so complex just building it and and you know it was it was over budget behind schedule and you know a few times during the construction and design suggestions were made you know maybe we should put on a grapple fixture or something just in case but but those were all all turned down i think they were just concerned they didn't want to do anything else which might over complicate or or delay the ultimate launch of the web telescope so it's not built for servicing and we do not currently have the capability to service it even if it were on the other hand if the deployment gets stuck halfway out you better believe that the whole world of spaceflight is going to be there trying to figure out you know what can we do to fix it even if we just have to send a robotic spacecraft up there to bump it a little bit but whatever it takes we'll try to do it too much is at stake wow that actually gives me a lot of confidence jim i understand that there are 300 different ways jwst could fail and do you want to run us through what's going to happen when it actually actually deploys that that timeline steve was saying it's a long timeline of of starting to get concerned well i'm not going to give you 300 steps in the timeline i mean there's one of the things that uh people need to remember is that hubble fitted inside the shuttle you know so the shuttle was big enough to deploy hubble uh james webb the mirror diameter is six and a half meters compared to hubble's 2.4

and that's wider than fits inside any rocket essentially so the mirror has to be folded up and therefore it's got to unfold properly and eventually it's got to be aligned properly with the right optical precision to make beautiful images and that's going to be a long slow process so the panels have to unfold it's to get aligned because the whole point as we keep saying is to get everything nice and cold and that's one reason it's going a million miles out from the earth rather than flying around the earth every 90 minutes as hubble does whenever you see a picture of hubble you can see it's only a few hundred miles above the surface of the earth this is going a million miles away it's going to be in sync with the earth and the moon going around the sun so it's not going to drift away into space but it's going out there to be kept cold but another big challenge i guess it's a mechanical engineering challenge really is to deploy this huge multi-layered sun shield that's about the size of a tennis court which has to basically sort of self-inflate and deploy as if when you go camping you hope you can self-deploy your mattress or something like that it's just got to blow up and expand and do his stuff and the reason that's important is we think that space is cold but this is not a way out in the edge of the solar system there's still a lot of light from the sun and in fact this huge sun shield is going to have a huge temperature drop across it so on the sun side apparently it's going to be about 85 degrees celsius or centigrade so that's nearly the temperature to boil water then it's going to drop all this temperature across the telescope side where it's going to be about minus 230 centigrade or about 40 kelvin in absolute units and then as we've heard from jillian she's got to cool her little camera and down to about 6 kelvin about 34 degrees colder so there's a great mechanical engineering challenge of just all this unfolding and deploying and configuring and then as i say it's a flexible mirror made out of all these panels and so there's going to be a long period where they try to take images of stars and a kind of feedback loop try to adjust the shape of all these hexagonal panels which are beautifully gold plated because gold's very good reflecting infrared light and it'll take a while to mold the mirror into the shape that it needs to be to to realize the whole power of the facility and in a way this is good i mean it sounds complicated but at least the controllers have the ability to change the shape of the mirror uh those old enough to remember may remember that the hubble space telescope mirror was the worst mirror ever made in the history of telescopes and had to be had to be fixed by inserting new optics into the the telescope through another of these astronaut missions so in some ways there's lots of things to happen but there's also a lot of flexibility in the telescope and i think we can take confidence that there's lots of things that can be adjusted on route to get it ready and i think i've given you about three out of the 300 ways it could go wrong thanks very much um jim uh now before i ask um our next question i'd like to um launch our next poll because i'd like to hear what you are most excited about what web might be able to see so we've got a multi-choice question here and there are three main things that we're um all for sorry the main exciting things that we're excited about with web obtaining new views of our solar system uh probing the atmospheres of exoplanets which i think is phenomenal revealing the birth of stars and planets and finding the first stars and galaxies to form in the universe so uh vote on that one and uh and while you're all voting um sam has noticed that the uh launch date for jwst has changed so we were all getting very excited about the 18th december for the launch date um unfortunately that um has been pushed back and um i have a lovely quote from jeff earlier who says nobody appreciates on-time failures so jillian you're closest to the the inside knowledge here do you want to tell us a little bit about uh what's what's happening at the moment at the launch site what tests they're running what's causing this delay so so i think um you've probably seen the the the press release nasa put out saying something went a little bit wrong when they were integrating jwst to the parts that actually attach it to to the rocket and as a result of that they've stopped and we're going back and testing things just to make sure that nothing's gone wrong and i and i think you know i i agree with jeff at this point everybody is just very very cautious super cautious because we're nearly there so why why rush two days when doing a little bit of extra testing will give us so much more confidence and are you worried about miria there is your team so mary is the camera that um that jillian's team built together um are you running tests specifically on miri as well to see if it's if it's all okay or is it mainly the structure of the telescope it's it's more of the thing it's more the things that are in the spacecraft so it's not really the telescope and the instruments that are a worry it's the spacecraft because that that's where that's where the two parts get attached get attached together okay so i've been telling uh everyone that we all have to behave ourselves so santa does deliver us this christmas present before christmas but um i'd much rather they of course it's been uh 25 years in the making so as julian said a few extra days is uh is is not not an issue now there are lots of questions about um hubble and james webb working in tandem and so steve was talking about this at the earlier that the hubble isn't dead yet it's still got some life in it in it yet um so so steve can you can you see um that hubble and james webb work in tandem what what sort of things could they um do together and and how much longer do we think hubble's going to ask um alex and matthew are asking yeah definitely so as i mentioned earlier hubble and web have different capabilities um so for example um web is really really an infrared dedicated telescope so it's designed to look at the infrared consequently it doesn't really look in the visible light that we can see of our own eyes or the uv and so when we find interesting objects with web we're probably going to want to look at them with hubble as well or with telescopes on the ground because by doing that we get kind of a more complete view of those objects so it's only really by combining all of these different views together the uv the visible the infrared radio x-rays that we really understand objects completely so i think that there will be a need for for hubble for a long time um i think it's a shame that we actually don't have right at this moment a plan for a like for like replacement of hubble although a plan is developing on the other side of the pond in the u.s um in terms of how long hubble is going to last it's really really difficult to say something could break we've had over the last well really the last 15 years they've been occasional hiccups where things have been broken and the telescope is out to be rebooted for lack of a better word or fixed with one of the servicing missions so i mean i don't like saying this as a scientist but you know fingers crossed that it continues going because there is really good synergies between hubble and web and and many of the other telescopes that we've got coming up over the next decade thanks very much steve um now the uh the results of our poll are in um and uh jim and steve you'll be pleased to know that people are most excited about web being able to find the first stars and galaxies to form the universe so jim you have been awarded one of the largest programmes on james webb so uh for those of you who don't know how this works astronomers put in a um a proposal for what they would like to do with a telescope and they ask for a certain amount of time and uh jim is the principal investigator of one of the projects that got the most amount of time jim are you going to find the first stars and galaxies in our universe with all of this time you're going to have on on the james webb space telescope maybe so yeah i mean this is a big program um i think we've learned some of the lessons from hubble hubble's been around long enough that at some point people started realizing that major investments of an observing time to produce data sets that were genuinely public could be accessed by all astronomers around the world was a strategic way to advance the subject quite substantially and that was perhaps best demonstrated when people first took the very deep images with hubble which nobody really thought they were going to do when when they built the hubble space telescope they weren't really on the agenda so there was an image called the hubble deep field that was taken uh under director's time and then released to the world and then the image i was already talking about this ultra deep field which is still the deepest ever image and so it's sort of in that spirit that we want to take a very deep image of two patches of sky actually uh do it in cycle one of the james webb's base telescope one thing we haven't really talked about is the lifetime of the james webb space telescope and the web might only last five years its target is 10 but depending on whether it runs out of fuel to keep it in position it could be five so if you want to do something big you've got to do it early and this wasn't really attempted in the early years of hubble because people knew it could be refitted and tried so in the first year of its operation so-called cycle one we are going to take these very deep images in the infrared and it's again this nice synergy with hubble we're going to take these images in patches of the sky where hubble has already done surveys in optical and uv light so that we can couple the whole the whole thing together uh and yes well we are running out of time i mean we've talked a lot about um i mean cosmic time not not just time to launch james webb space telescope so i mean we've talked a lot about the great thing about astrophysics in a way is that it's got something for every everyone i mean we've talked about engineering there's james webb is a feat of mechanical engineering electrical engineering software and computing cryogenic refrigeration engineering satellite navigation communication data downloads but at some level it's being built to do something i think more fundamental which is to try and work out when and where we all came from and there's a reason that physics used to be called natural philosophy and and it's close to philosophy so i think people want to know when and how the universe started they want to know when our planet was made they want to know when life started the work that you know the reason that poll was probably won there for the first stars and galaxies is that's one of the big creation moments in the universe because after the big bang there only was hydrogen and helium and nothing else and a kind of structureless void that people call the dark ages and the switching on of the first stars what you might call first light in the universe it's not just about first stars these first stars would be the first things to manufacture carbon nitrogen iron oxygen everything that's going around in your blood everything that made us so this is a almost a creation experiment when did that happen and we actually hope with this survey that we might be able to see some of the signatures of the first stars and galaxies which might be very hard to see because it might be very brief they'd be just made of hydrogen and helium just at this moment before they create the rest of the periodic table you also on the side of your chemistry classroom when you were back at school all of that is made in these first styles apart from hydrogen and helium sitting at the top so i think you know even if you're not interested in engineering or science most people are interested in the history of us and this is some kind of fundamental moment in the history of us the the cosmic dawn it's called i love this idea of the universe first first coming to light um thanks jim and let's go back to our poll though because uh it was a it was a close run it was a close run race in the poll there and if i remember rightly the second um most voted for in the poll was probing the atmospheres of um of exoplanets and who on the panel wants to tell us a little bit more about that does anyone want to jump in on that one i can jump in a little bit so this is obviously uh the complete other end of the the scientific spectrum what web is working on from what i normally work on but i've i've i've had the benefit of listening to many talks about exoplanets and it really is one of the most exciting bits of science that web is going to do i think part of the reason why it's so exciting is because it's such a new field it's only in the last 25 years that we've been able to discover planets outside our own solar system and we went from in the mid 90s from knowing about zero planets outside the solar system so only knowing about eight planets or nine planets if you can't count pluto to now knowing about thousands of planets in the universe and over the past couple of years we've not just found these planets we've been able to study them being able to work out how big they are how close their parent star they are how hot they are lots of different characteristics but with webb we can push this that little bit further we can actually analyze the atmospheres of those planets we can start saying what the atmospheres of those planets contain so we can look for things like water and methane carbon dioxide maybe even oxygen via ozone and once we start being able to do that experiment we might be able to start saying even more interesting things about those planets maybe they're habitable right if we see the right combinations of things in their atmospheres maybe it's somewhere that we can go one day in the distant future so i think the idea of of maybe somewhere down the line and whether or not web will do this i don't know at the moment but maybe somewhere down the line starting with webb we might be able to find a planet like the earth and i think that's tremendously exciting it's kind of a different sense of creation that jim was talking about but it's seeing something else like our own planet i think is tremendously exciting as well but boy measuring the atmospheres of exoplanets the precision of the measurement which is required to do that is just unbelievable you know tiny tiny fractions of a fraction of a percent that you're actually trying to measure it's amazing that we can do it yeah that we've built this this civilization on planet earth has managed to build these incredibly powerful space telescopes to to be able to let us uh do these uh these sort of science did you know i buttered in what were you going to say oh i was thinking that that it's important as well most of the ex-planets we found so far they're quite big and they're quite a long way from the parent star so they're not at all like what happens in our solar system and i think with webb will start to be able to join the dots up a little bit by finding smaller planets things that are closer to their parent star and i think that's going to be really exciting although as i guess as jeff will probably tell us i mean often astronauts say that the thing that they most notice when they go into space is how precious and unusual and hospitable our planet is and so although we've not found many athletic planets so or any exactly yet it's most planets are pretty inhospitable places that we've discovered so far so there's that perspective as well and sometimes make us just seem more special you certainly get a sense uh you know knowing that on the other side of of my space helmet is a vacuum where i couldn't live for 10 seconds it gives you a really gut feeling of the ultimate hostility of almost all the universe to any any kind of life and so the the search for places in the universe that might allow life at least life as we know it is so important it's very rare it's very rare so so i'm so jealous of you jeff i'd love to look down we have a question from jay that's been um very upvoted so i want to make sure we switch this in i'm going to give this one to jeff and jay's interested in what is the um what's the most important thing in the difference between james webb and hubble is it to do with how it's capturing the images the clarity of the image why is it important to get these telescopes up into space why don't we just do these observations from the ground fortunately the earth has an atmosphere otherwise we wouldn't be here um and the atmosphere protects us from cosmic radiation from x-rays it also protects us from ultraviolet and a lot of infrared radiation which just doesn't get down to the ground um and and to be able to to look at the entirety of the electromagnetic spectrum which is what astronomers would like to do the more of the spectrum you can look at the more information you get and that's why we go to space astronomers have figured out how to do incredible things from the ground we can we can actually eliminate a lot of the distortion that is created by motions in the atmosphere which you know 50 years ago people would have thought was impossible but but we can do that but uh you can only do that for the light which gets through the atmosphere and and so much of it doesn't in terms of the difference um you've already heard about the size uh web is is larger than hubble and therefore it can collect more light which means it can see dimmer objects and for a given object the farther away it is the dimmer it is which is why we'll be able to see things with web that we can't see with hubble hubble basically took the telescope technology of the mid 20th century a big chunk of glass which was made into a mirror and that's what we put into space telescope technology on the ground advanced towards the end of the 20th century we were using telescopes with multiple mirrors so that we could make them much bigger and that's the technology of the webb telescope it's the technology of the late 20th century and that allows us to make it much bigger and then you've already heard about the fact that it has to be cooled so that it can see infrared so those are the main differences now i think our discussion of uh sort of looking back down on planet earth and thinking how fragile it is has made me motivated this next question and from our audience which is um given given the pressures that we're on on earth at the moment um climate change food insecurity you know we've spent 10 billion us dollars on uh the james webb space telescope was it worth it should we be worrying about our planet more um steve i'm going to pump this one at you what's uh what's your take on that thanks giving me the easy question there catherine so i mean i thought i thought long about this as an astronomer and i think there's really three things that come to mind here so first of all telescopes like web and hubble they're allowing us to understand our universe in more detail um that's not isolated from the rest of science so by learning about our universe we learn more about the world here so we learn more about fundamental physics for example and we know fundamental physics ties in with uh our understanding of chemistry and then biochemistry and then biology so it's all linked so by making progress in one area you're helping progress across all of science so i think all science is worth doing because it helps all over um i think secondly and it's kind of related but lots of the technology that we've developed for astronomy and astrophysics in particular for space telescopes have been used for different purposes so the very first observatories that we made were made to look out we're made to look at the sun and then um further out and then we started looking back down to the ground so there's been lots of technology transfer between astronomical observatories and kind of remote sensing so actually observing our own planet and it's via that remote sensing that we've learned more about climate change that we've identified things like the ozone hole we've worked to fix that one particular problem so and then there's other areas of technology so the astronomers would often say how um we helped develop things like wi-fi which i'm sure many of us are using right now um our cousins in particle physics will often claim that they were responsible for the internet and that's not completely untrue so it's all connected but i think finally i think the one that i'm the most passionate about is that i think astronomy is very accessible so anybody can look up at the night sky and can wonder about our universe and the images that hubble take and that web will take they inspire people to study science to become more scientifically interested and literate and i think that can only be a good thing because those people won't necessarily become astronomers they might become biologists or chemists or engineers and i think just having more people interested in science is always a good thing and i think astronomy is really really good for that if can i chip in here we should have buzzers here like excellent answer i mean i was once at an event where i remember one of the people who was in charge of one of the mars rovers getting a kind of accusing questions saying you've spent this many million pounds of gold minutes on miles and you gave a very good answer that the the question i was almost sort of saying well you've just thrown that that money is literally lying around in the surface of miles and of course with 10 billion pounds it's mainly gone jill and i'll tell me if i'm not it's mainly been spent on people's salaries so this is an investment it's almost a piece of infrastructure it's an investment in exploration and investment in engineering skills and training people as well as inspiring people and it takes roughly the same amount of money to build one nuclear submarine so you need to keep these things in perspective the world's greatest ever observatory funded by the whole world is about a 20th the cost of replacing trident and i suggest more inspirational do you mean i'm sure you'll agree yeah i think i think the the whole the way science is all joined up and and but technology's joined up to so things we've learned to do in order to build jwst we can learn to do them because we only need to build one of them if you want to apply those techniques say with how you analyze light and you want to apply that to something medical then you're not trying to make one you're trying to make thousands of them and so and so sometimes in astronomy we can take the first step in technologies that then move out into other things you know the other another thing is with with the interest in preserving our own planet keeping the earth healthy it's important to understand how planets work and the best way to understand how planets work is to study lots of planets if you only study one planet it's very hard to figure out you know how planets work you know the greenhouse effect we really came to understand that scientifically through observations of venus when we discovered through radio astronomy that the surface of venus was was so incredibly hot because of the carbon dioxide in its atmosphere um and and you know who knows what the more we can study about the formation of earth particularly earth-like planets around other stars we may learn a lot that's important in keeping our own planet healthy thank you jeff now we're in our last few minutes and um i think a really lovely way to end would be with a question from liz and i'm going to punt this to jillian first and then to jeff so liz is asking what advice would you give to people both young and not so young who are keen to take on a career in astronomy i would say trust your instincts do do what interests you there's many a career in astronomy can mean many many broad and different things and so follow follow the path that that leads you to where you feel comfortable taking part thanks and to jeff what advice would you give to people young and not so young and astronomer royals for scotland who are keen to take on a career as an astronaut um becoming an astronaut should be your plan b that's what i tell my students when they ask me because the competition is pretty intense make sure you have a good plan a because when you apply to be an astronaut um they're gonna look at what you've done uh excellence in everything you do uh and whether you're a physicist or a biologist or or a medical doctor or or an engineer uh you you better be a damn good one uh and if you want to be a good one hopefully you'll be doing something that you enjoy so yeah figure out what what you're good at what you enjoy doing and by the way you better get a lot of math in in all of these things you you know you you you need a lot of math um of course if you want to be an uh go into space the alternative is to become filthy rich sorry to have to bring that up but there are a lot of other people going in in a space now for for most most astronomers and and people that that's not an option though so no i just need quite seriously it's not an incredible dream to have it's very motivating uh so many people have said that they you know they've gone and and studied science because they got excited about the apollo program and and watching the shuttle launches and and and just uh you know work hard and and when it comes time to apply to be an astronaut hopefully you'll have good qualifications thanks jeff um jim very briefly is web scientific legacy going to equal or exceed hubble's if all these 300 things work i think it's very hard to i mean hubble's been so amazing but i i think in the long term yes it could it could be as comparable to hubble and steve um this one from malc in put yourself 20 50 years in the future what are we going to be discovering then oh we're going to be we're going to be making maps of planets like the earth around other stars we're going to be able to see continents and oceans and we're going to see trees on those planets uh not directly obviously we're not going to make a nice picture of a tree but we're going to see the signatures of trees that is if life is abundant in the universe which i i hope we all hope is and of course we're going to see the very first stars and galaxies but me and jim are going to do that in the next five years so don't worry we'll have that one figured out thank you so much to all of my panelists this evening professor jim dunlop professor gillian wright professor jeff hoffman dr steve wilkins thank you so much for joining us i'm afraid i'm going to have to bring this conversation um to a close i hope that you have all enjoyed this event as much as i have and please do continue the conversation on social media remember even though it is winter a hashtag is still summer science because we are celebrating this evening the royal society's summer science exhibition and it was all digital this year so if you've enjoyed the discussion this evening then please go on the royal society's youtube channel because there are lots of different things that you can find there that have already taken place there are new events coming up as well so sign up to the royal societies newsletter and check out their website and if you could take part in our short evaluation survey we'd really be very grateful and so we can make events like this even more amazing in the future please do go to uh the uh the amazing digital content on the royal society summer exhibit there is a space telescope simulator and an app to make your own space image so check that out thank you so much my panelists thank you to everyone who asked questions this evening um and that's all for tonight um please do join the royal society events again another time and it's goodbye from me you

2021-11-27 12:33

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