The Supermassive Podcast - 54: BONUS - Overmassive Galaxies

Episode Date: July 20, 2024

The Supermassive Overmassive Podcast has a special bonus episode. Join Izzie, Dr Becky, Dr Robert and Richard as they discuss the last two years of JWST and share their recommendations for Space Book Club.  Recommendations: Unseen Universe: New Secrets of the Cosmos Revealed by the James Webb Space Telescope by Dr Caroline Harper  The Possibility of Life by Jaime Green When Galaxies Were Born - Richard Ellis  Challenger: A True Story of Heroism and Disaster on the Edge of Space By Adam Higginbotham

Hello and welcome to another bonus episode of the Supermassive podcast from the Royal Astronomical Society. With me, science journalist Izzy Clark, astrophysicist Dr Becky Smethurst, the Society's Deputy Director Dr Robert Massey and producer Richard Hollingham. This is the place where we dive into the Supermassive mailbox and answer all of your fantastic questions that you sent in yeah but we've covered a lot of questions recently okay so this episode i'm bringing back the space book club uh but to be honest i'm gonna welcome exhibitions film and tv recommendations oh nice some of us don't have time to read four books and when i say some of us, I might mean me. Yeah, and me. But before we do that, I thought we could have a check-in

because it's been two years since the first images from JWST. So I wanted to have a look at, you know, what's happened in those two years? What have been some of the latest discoveries? Because I think when we first had those images, we talked about web all the time and we've moved on. We haven't checked in with them for a little while. So this is a good opportunity to do that. So what have been some of the latest discoveries that have caught your eye? Shall I start? Yeah. I mean, the one that strikes me is this ongoing Hubble tension, which is still, I guess, not going to be uncontroversial,

but the discrepancy between the scale and the rate of expansion of the universe implied by Planck and looking at the cosmic microwave background and the overall structure and what we see in terms of the redshift of galaxies. So what J. Davis T has done is looked at Cepheid variables, which are stars that vary in a very regular way so essentially the rate at the period the length of time over which they vary is related to their brightness and therefore if you see the variation you know how bright they actually are and then you compare that with how bright they appear to be and hence you know how far away they are now they've done it's done that in a galaxy 130 million light years away which is much much further than we've done before and it

still finds this tension so it still finds that there is this discrepancy it's not vast but it's there and it might mean things like dark energy is more powerful than we thought it was and you know cosmologists love this kind of thing because it you know allows them to carry on developing ideas about the universe but it's really fundamental i think i mean it depends who you talk to roberts if you're some people don't like it well it's a little bit of chaos to be honest. Some people don't like it, I imagine. Well, it's a little bit of chaos to be honest. I think there's two main groups that are looking at this with JWST at the minute.

And one group says JWST still finds this difference between the two main methods we have for measuring the expansion rate of the universe, right? And JWST is focusing on one of them. And we thought with JWST, it would explain the difference away and it didn't. But then the other group, who technically haven't published a paper yet, but have been sort of presenting their results on the conference circuit this spring and summer, are saying

JWST has got rid of this tension. And actually now they agree with Planck, these two different methods. So Planck being one of them and JWST's version being the other method. And so, I mean, we're all very confused i'm not gonna lie to you i think waiting for a definitive paper yeah exactly i think that's what everyone's waiting for so that they can dive into like how like what part of the problem did jdbst like you know get you know change to make everything all of a sudden you know agree again with the rate of expansion you get out so it's just i mean it's so funny when i talk to my cosmologist colleagues because i am not a cosmologist i'd never claim to be one it's i see it's very complicated and um you talk to them and they're all like oh

i don't know that's not my niche i'll just let them figure it out and so it's just these two teams that are trying to work on this and you can just tell people they're almost at like there was impatient now they're almost impatient now. They're just like, could we just figure this out already? Not as clear cut as we necessarily hoped it would be. Yeah. So my other one is easier, I think, at least conceptually, which is that there's a really nice image of the Horset Nebula. It's just one of my favorite objects. It's really hard to see with your eye, but lots of astrophotographers actually find it quite easy to take pictures of it's a dark

nebula in the constellation of orion and it looks like a horse's head and what jwst does is zoom in on the top of the main of the head if you like of the horse and it's a sort of super close-up so it's looking at what you might describe as a small by astronomical standards 0.8 light years across section of the nebula and it sees all the infrared light from the dust and soot there so it's looking right inside one of my favorite objects so i'm not sure that counts as a discovery but it's something that i thought was a nice oh definitely so nice and did you see the image that came out from the euclid space telescope as well of the horse head i did i did i mean it's just this favorite target for astrophotographers and for astronomers for

professional astronomers too and I think what was so wonderful is that it showcased the strengths of each of the different telescopes of like Euclid Hubble and JWST so Euclid launched last year and it's it's not a telescope like Hubble and JWST where like you know us scientists can just apply to use it you know and if you're successful you get the time and the data Euclid is just sort of doing a survey of the sky and so because of that they've given it this huge field of view so it looks a much bigger region of sky at once and so you have the Euclid image which is massive next to the Hubble image which zooms in a little bit more because its field of view is smaller and then JWST which you know zooms in again with that super high resolution and just seeing the three of them side by side is just amazing i i was blown away by those images and it's so nice just to compare them as well it does just it's just really exciting when you keep having those

different points of view and so becky what about you what are you excited about you know the past two years of web i mean so i think it's funny with web web was designed to you know really tackle the most distant universe and then the exoplanet people the community were kind of like oh infrared that would be helpful for us and they sort of piggybacked so it's really fun to see how i think the two biggest areas that it's impacted on are the most our understanding of the most distant universe and then our understanding of like exoplanet atmospheres and so i've really been following those two the most um in terms of the distant universe like we had like the most distant supermassive black hole possibly found uh this month as well which obviously i was very excited about because it helps us work out like what epoch of the universe did black holes first form and how big they were able to grow in such a short space of time in the very early

universe. And what we're seeing is really confusing to us because it doesn't really make sense in terms of what we know about how black holes grow and when we think they form and how big they are when we think they form. So it's giving us lots of questions around that and similarly one of the big things that people have been talking about and sort of being confused about is what we've sort of dubbed over massive galaxies in the early universe have you heard about this is no i haven't actually yeah so really distant galaxies that jd bruce t has been finding that like we've confirmed like they are really that far away right with the with the light that we get from them when we then work out their mass so like from the light you assume like okay there must be sort of this spread of stars there and so to account for that much light that we're getting those stars like they you know there must be this many stars there in

total and therefore this mass of stars when we work that out they're so much more massive than they should be in terms of our models of how galaxies and stars first form in the universe there's only like you know you only have so much time to for everything to collapse and form and come together so there shouldn't be galaxies that big at that time in the universe's history and people are like what when i saw it and i thought i think that the latest one was what 1600 light years across they're small by contempt by the present day universe but presumably much bigger than the models say they should be yeah well this is the thing that people have been trying to work out is is there something wrong with our models and can stuff form much quicker or perhaps do stars, you know, form at much higher masses in the early universe?

Is that possible? Like there's sort of like an upper tail end of stars that we see in our own galaxy around about a few hundred times the mass of the sun, but could it be bigger in the early universe? Or I think the one that I'm most convinced by is that step that I said in the middle is that you go from, you know, the amount of light that you see to the mass that you have. You have to assume there's some spread in the stars that you're seeing. So like some distribution of you've got this many low mass stars and this many high mass stars and you can draw a graph of like this is how many you get.

And we get that graph from looking at stars in our own Milky Way. But that might not be the case. Again, there might be more massive stars in the early universe it could be a different spread and so if you have that different spread that massively changes things and there was a paper that came out last year showing that if you assume there's more heavier stars in the early universe you know and you skew that graph a little bit then actually the masses that you get uh for the you know how much mass is there and with how much light we're seeing are much lower and do fit with our models that we have so it could just be this spread of stars that whereas this is this assumption step

in the middle it's something called the imf always makes people laugh it's the initial mass function not the international monetary fund it's the imf and so i think it's probably something to do with that but it's so interesting to see how my colleagues have reacted to it because we see this one oh massive galaxies that's weird uh yeah okay so it's probably something to do with the imf there's some assumption that's wrong versus like the media and the internet that are like oh my gosh the big bang is a broken no so that's been really fun to sort of watch play out and you know a headache to them trying to explain no it's probably this and then from the other end of the spectrum the exoplanet stuff i think that's been a so exciting to see like jwst like come

through on being able to get these exoplanet atmospheres but b also just watch the struggle in the exoplanet community as they deal with this data i know i think there was a lot of hype around the trappist system do you remember this yeah like seven planets around a red water i think i mean the fact that the data they're getting from them is so difficult to work with i just don't think they're getting the signal it sounds like they're probably just like rocky balls with no atmospheres which is why we're just you know not getting anything from them right but who knows we'll wait for those papers to come out the ones that have come out so far travis b and c have just been like it's just bare rock probably um but then there have been other planets that you know they've been able to

get the atmospheres from that have obviously caused some stir and some headlines. The big one was K218b, which was a planet that is sort of like super earth mini Neptune, right? It's somewhere in between the two of them. And there was a claim last year that there was evidence for something called dimethyl sulfide in the atmosphere from the JWST data, which on earth is produced by bacteria. And so it's long been thought it could be like a bio signature like a signature that life was present in the atmosphere and obviously again the media was like oh my gosh jd wisties found evidence for life whereas you know all the astrophysicists looked at the paper and was like that's really weak evidence it's not even like over the threshold

with which we would claim we found something right okay um oh if you use this different model then it's not there and oh it could just be methane and not dimethyl sulfide because you find this signature of dimethyl sulfide in the same place as methane and oh we're gonna need new data with jwst to check that and all this kind of stuff that should be coming soon and hopefully should figure out what's going on with this planet because again like i think it's one of those things where if you're not careful as an astrophysicist with the press release that you put out on this paper people are then like when you know if we do actually find a biosignature that's much more strong of an evidence and we can be really sure of in the future and

people say oh the first biosignature found people might be like oh didn't we already do that you know and be almost like blasé about it so you have to be really careful with like how you communicate this stuff because we really are like you said is we're just two years into jwst i was just thinking this i was like we've covered so much i'm like wait this is two years i mean already the data that we're getting through is just insane levels of people even being able to get through it yeah simultaneously i totally understand what you mean that we have to be careful with what we communicate and how we communicate but if you take a step back it's just really exciting oh yeah it's just so exciting can i just put a shout out for um for hubble at this point because you know oh yeah you know poor old hubble it's been in orbit now since 1990 and okay it didn't work to start with but it got fixed in

orbit which was also a remarkable achievement and it's just back in business it's been having a few glitches over the last few months it's now back in business with just one gyro working which is uh what's used to sort of track and follow objects in space but it's still working and to have Hubble and the JWST at the same time I just think I wish this is a golden era isn't it of space astronomy it really is it really is and I think that's why people are you know so so so excited about any new discovery that comes out and everything like that it is just incredible but I also think it's really been good to sort of like you know just talk about this is science in real time like we're really living through the confusion and in a a way, that's almost more exciting

than getting all of these clear-cut answers. Yeah, totally. Maybe that's just me, though. I really like the phrase overmassive podcast. I think that is great. This is what this should be called. Yeah, exactly, the overmassive podcast. Because it's the bonus episode, so that totally makes sense.

I've written it down. Oh, well, maybe we'll be changing the name. Right, I'm going to move on and open up the Space Library. So what are you recommending for Space Book Club? Becky, let's start with you. Yeah, so I read The Unseenoline harper um this past month which maybe i can be described as a jwst picture book so i guess it um it's good for this episode but you know it's all the stunning web images just printed so beautifully and then they're explained with

this very wonderful like really accessible text you know a level that everyone can understand to explain all the images so you know the images get more beautiful when you know what you're looking at as well you know which I always say that's that's my favorite thing and Carolyn Harper who's the author you know she's head of space science at the UK Space Agency as well so you know you know she's got the expertise and the inside info for it as well because she'll have been involved in for example like the Miri instrument on JWST so yeah it's a really cool book i can highly recommend it for people and then isn't you said before that you would also take exhibitions tv shows film recommendations all are welcome okay yeah everything's welcome well and i've got to

recommend the moonwalkers exhibition at light room in london have you seen this so good yeah it's one of those um it's one of those rooms people don't know where you know where they've got like like almost like projectors or tv screens around the. Yeah, it's one of those rooms, people don't know, where you know where they've got like, like almost like projectors or TV screens around the entire room. So it's one of those completely like immersive room experiences. And this is like basically the story of the Apollo missions. So if you imagine all of the amazing images that were sent back from Apollo, imagine being immersed in those.

So you feel like you're on the moon. So, so good. I've been to it as well we were lucky enough when we went to see it um to sit next to uh one of the original apollo flight directors jerry griffin oh wow of course you did of course we did yeah who we interviewed for the um the space boffins podcast he was amazed by it as well he enjoyed it and he obviously he was he was part of it i think the the bit for me it's not just the stunning images. And they're even more stunning now thanks to the work of Andy Saunders, who's done these amazing advancements.

But there was a point in the show where you're in Mission Control and where you're sitting. You're suddenly at a console in Mission Control. And sitting next to a flight director in Apollo Mission Control was just extraordinary. Absolutely, absolutely extraordinary. So yeah, thoroughly recommend it. We probably need to stress to visitors that they won't all get Apollo flight.

No, I think that's... Which is a shame, you know. One book I have read and one I haven't. And these were both sent to me for the podcast. So the first one is The Possibility of Life by Jane Green. And she a she's a US author and she writes really really well I think about the way in which we might respond to it and the different discoveries that have shaped it and includes things like the you know the putative detection of phosphine on Venus so

I do recommend that and it's a really intriguing way of thinking through it so she sort of describes she imagines how humanity reacts the kind of processes we go through so if you've ever wondered about that then i recommend and of course she also talks about the signatures we're looking to try and understand whether there is life you know the bio signatures all these things that make it you know i mean we're looking really for tentative detections a lot of the time and then trying to confirm them so so i really strongly recommend that what i'm hearing is that it's like if contact really happened like yeah yeah well she does reference that yeah she references science fiction a lot as well and she kind of talks about the different ways it's imagined and in fairly recent books as well so i'd uh you know i'd recommend that um the other one is uh one by

richard ellis who actually won a medal actually various medals in the Royal Astronomical Society and lots of others and he's a long-standing cosmologist and galaxy guy and he's written a book called When Galaxies Were Born and the Quest for Cosmic Dawn and he talks about to some extent it's autobiographical so it's talking about the 40 years of science and what it took to get to where we are today to understand them and of course you know as we've heard from JWST is actually still, you know, this isn't over.

It's not completed science by any means, but it's really interesting to see how he tracks it right the way through from say the 1970s, 1980s to where we are today. Nice. Okay. Well, I'm going to break the rules of book club and recommend a podcast because that's how I roll. Not this one. Yeah. I mean, obviously i recommend the supermaster podcast to everyone but that is a biased opinion um so i'm now going to

recommend crash course pods the universe so this is where dr katie mack who we've had on the show before you know she's the theoretical physicist physicist behind the end of everything astronomically speaking in this series she goes through step by step the history of the entire universe with a best-selling author john green so they've done the beginning of the universe sort of the fundamental forces the dark ages of the cosmos and then you know the birth of stars and they've called it when stars turn on so it's just a nice little guide through the universe when you're missing us you can jump over to to that podcast series and obviously if we're recommending podcasts then we also have to mention space buffins yes thank you thank you very much thank you very much

in fact our may podcast i think is the best one we ever did. So we have astronaut Victor Glover, who is extraordinary. And also the extraordinarily named Mason Angel, who's made his money in finance and had a blue origin flight recently. And the two of them together are just extraordinary. So it's a great podcast. Sorry to end on a bit of a downer, but I want to recommend a book called Challenger, the true story of heroism and disaster on the edge of space. So

I've seen it advertised a lot in the UK. I don't know whether that's true in the US as well. It's by Adam Higginbotham. I think Higginbotham, I should say. And it's really, you know, around the events of Tuesday, the 28th 1986 with the explosion of the Challenger space shuttle killing all seven crew including the teacher Krista McAuliffe and it's a gripping account I knew a lot of this stuff before and most of it I would say has been written before but you really feel the way he's written it and it's extensively researched. You feel you're in these meetings where these flawed decisions were made

and this insight into this incompetent management, the political pressure, the media pressure under launching Challenger. And there's quite a lot of foreshadowing, the problems with the tiles on the orbiter, the fundamental design of the orbiter, the problems with these solid rockets. I mean, the whole system was pretty flawed in its design, but it's really well written. It's not overly gruesome. It doesn't dwell on the aspects of the disaster particularly. And it really just,

it's shocking in terms of just laying out the incompetence behind the disaster and many of the same mistakes made then later with Columbia. But really good read. I did take it on holiday. Really good read and pretty gripping and nicely documented, laid out. And yeah, you just feel you were there and you just feel, no, don't make that decision. Don't do that.

Why are you doing that? It's incredibly frustrating all the way through. But very, very good. Very good book. It deserves the publicity it's getting. And similarly, like there was, I mean, I saw it on BBC. I think it might have been an American produced programme, but it was called The Space Shuttle That Fell to Earth,

which was a doc on the Columbia disaster. And it was aired, like, I think it was back in March. Yeah, it's on iPlayer, yeah. It's three episodes. And and again that's so similar it's a gripping documentary that actually interviews people who were making the decisions as well and it's one of those things where you can just see at every single stage you're just there like screaming at the tv like no no like make a different decision you know yeah it's so powerful when you watch it. Yeah, it's so frustrating. I mean, you're seeing now, at least with NASA's new or Boeing's new spacecraft, Starliner, which has been very much delayed and launched recently, the caution. You know, let's hope those lessons have been learned. The caution in taking it step by step and only launching when they're ready and not giving in to that pressure.

And I think particularly with NASA, it's that political pressure to launch at all costs. Yeah, yeah. Well, yeah, a bit of a downer, Richard. Yeah, sorry, sorry. I'm very much looking forward to developing the Overmassive podcast. So, you know, that's a must. Yes, definitely, definitely. Well, thank you for all of those recommendations um i'm gonna put all of them in the show notes so if you want to get any of those books then that's where you can find them and we'll be back in a few weeks time with an episode all about

venus and until then everybody happy stargazing