Ep. 684 – Too Big, Too Soon: Massive Early Galaxies Defy Expectations

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Fraser Cain [00:01:50] Astronomy Cast Episodes 684 two big two soon massive early galaxies defy expectations. Welcome to Astronomy Cast for weekly fact space journey through the cosmos, where we help you understand not only what we know, but how we know what we know. I’m Fraser Cain and the publisher of Universe Today. With me, as always, is Doctor Pamela Gay, a senior scientist for the Planetary Science Institute and the director of Cosmic Quest. Hey, Pamela, how you doing? 

Pamela Gay [00:02:14] I am doing well. I love the fact that you can say that exactly the same every single time. It’s it’s delightful. 

Fraser Cain [00:02:24] I’m just reading from a script. 

Pamela Gay [00:02:25] Except you said episodes, and I love that the content for this singular episode is so great that it needs to be referred to as a plural. 

Fraser Cain [00:02:34] Do you see episode 684? 

Pamela Gay [00:02:36] You did. It was delightful. 

Fraser Cain [00:02:38] But episode. Episode 684. Episodes 684. Now, like I said, episode. It’s just it. Just the way I say it is exactly the same. So I’ve been playing with the Merlin app, which is this bird. App that you can get and sell on your phone, and it lets you like report sightings. And it’s great for ornithologists to be able to count birds and so on. And the the has a gadget that you put on to it. That will do recording sounds. Yeah. And so you just put it outside and you listen for bird sounds and then they just as it hears a bird, it just adds it to this database in front of you. And so you’re, you’re hearing these birds sing all around you and you’re like, oh, that’s a chickadee. Oh, that’s a junco. Oh, that’s a toee. And and then you get rare birds too. And I had so much fun. And then and what’s been amazing is, is that now we’re starting to hear these birds and we look, you know, with like, oh, there’s a ten injure. And I’ve never seen a tanager. Never heard of a tanager before. And then you look up pictures, you know, like what a great bird. And then suddenly a couple of days later, you see the bird and you’re just like, that’s a tanager. Yeah. Like he landed on our fence. And Carl and I were both just, like, watching him just oohing and eyeing at this beautiful bird. Beautiful. Bright orange. Yellow like a like a tropical bird. But in the, in the temperate rainforest. So, I highly recommend this, this app, if you are interested in birds at all. The it’s called Merlin and it just, it’s just it’s so much fun. And then find some friend to get into birds and and ship with. And then you just like be on my life list. It’s 57 birds. My life list is 76 birds. So highly recommended. 

Pamela Gay [00:04:35] That that is that is absolutely amazing. We we actually, here in Edwardsville, we’re able to accidentally prove a research paper. I read a paper a number of years ago about how songbirds are less likely to live near busy streets because their song gets drowned out. And I have an identical bird feeder to one of my friends who recently moved to town, and she lives far enough back from all of the busy roads and this super quiet little neighborhood that backs up on the high school. And she gets songbirds all the time. And I never get any songbirds in two miles apart. And the only difference in our neighborhoods is how busy the streets are. And, so it’s weird is how localized things like that have allowed research to be done. And now we’re seeing the results proved out. 

Fraser Cain [00:05:27] It’s called theory proof. That’s amazing. Yeah. One of Ghost’s top jobs is to peer deeper into the universe than ever before. Watching as the first galaxies came together, surprisingly, astronomers found galaxies that seemed much more mature than expected, much earlier than it was believed possible. What’s going on? And what does this mean for cosmology? Okay, so like, why does he so good for this job? Why is it the perfect machine for seeing early into the universe? 

Pamela Gay [00:05:55] Well, it’s that whole infrared thing that we’re just going to keep bringing up over and over and over. Light From Young Stars is peaking in the ultraviolet. But because the universe is expanding, and the further away you look, the more stuff there is between us and that to be expanding. We see the most distant parts of our universe as moving very fast away from us, which shifts all that ultraviolet light all the way through, visible and into the infrared, where it’s easily apparent to the James Webb Space Telescope. Now, the thing is that there’s the other side of this, which is you need something with high resolution cameras, because right now, our best way, not our only way, but our best way of imaging these things is to look at galaxy clusters that I use their mass to bend light towards us, that otherwise would have gone to other parts of the universe, and that added light from the event light, magnifies the brightness of these distant objects. But we need the high resolution, and we still need the light gathering power of the massive mirror of J ust to make out those faint smudges of light that are getting gravitationally lensed. 

Fraser Cain [00:07:22] So. So the galaxies that we’re seeing, these ones, these impossible galaxies that we’ll talk about in a second. They’re being seen thanks to the gravitational lensing. Or is he able to just see some of these just with its raw capability? 

Pamela Gay [00:07:40] It’s it’s capable of seeing it through the raw capability. But we first started seeing them and we have seen the largest number of them so far through this gravitational lensing. It’s it’s basically the low hanging fruit. It takes fewer orbits. And you can honestly get a whole lot more science for the hour. If you look at a galaxy cluster, because you get the galaxy cluster and you get everything that’s in the background of the galaxy cluster. 

Fraser Cain [00:08:09] Right? 

Pamela Gay [00:08:10] So by the numbers, that’s how we’ve seen the most. 

Fraser Cain [00:08:12] And it’s almost like the first time they turned this on, they found a bunch of these really big galaxies. And they’re studying them. But they’re are deeper like all sky. They’re not all sketches but deep field surveys, like what happened with the Hubble Space Telescope in the works. Yeah, hopefully we’ll see a lot more of this kind of stuff and get a better sense of like it’s like a survey of them, as opposed to seeing the low hanging fruit, the weird stuff right away. 

Pamela Gay [00:08:39] And the stuff that was lucky enough. I don’t know if that’s the right word. We were lucky enough, was aligned to allow gravitational lensing. That that’s one of the the statistical frustrations is if you look at a mostly empty patch of the sky, like they did with the Hubble Deep Field, like they’re now doing with shelves, t that deep field. And you look and you look and you look and you look, you can say in this volume of space, which is a cone that increases as you look back, there is this population visible. And, and it’s a by volume measurement of what’s visible as a function of brightness. So you’re not going to see the fainter stuff for the stout, but you’re still going to know in that volume of space what is typically going to be seen now with, with J s t. They’re looking at galaxies that just happened to be oriented just right behind these clusters that they’re light, that in some cases originated just a few hundred million years after the Big Bang. Their light has been bent our way, and we’re not necessarily seeing their neighbors or neighbors didn’t necessarily have all the right geometry. Right. So it’s it’s not that same careful volume, limited statistical sample. 

Fraser Cain [00:09:58] And what were they expecting to see. Like I’m sure as they put they probably spent more time building models trying to make expectations figure out their calibration before they took those first images. What was sort of the the default. Astronomical expectation of what they would see. 

Pamela Gay [00:10:19] So. So what we’re guilty of always doing is looking at the cosmic microwave background, which is the rabbit hole. We shall not go down. And looking at the modern universe and figuring out what had to happen to get from the distribution of little tiny, denser and less dense distribution in the cosmic microwave background to our current large scale structure, and we make assumptions about, okay, so if you have this mix and you have dark matter that has this temperature, and you see this happening at this point in the universe and this happening at this point in the universe than in the section of universe we know nothing about in time. Right? These things must have happened. Right? And and so we made assumptions based largely on the distribution of hot and cold patches in the cosmic microwave background. And we expected that there would be a very small number of large ish galaxies forming that resembled the distribution of hotter spots in the cosmic microwave background. We figured there’d be a whole lot of itty bitty little tiny stuff, and there was more matching the average distribution of warmer spots in the cosmic microwave background. 

Fraser Cain [00:11:44] So? So astronomers looked at the cosmic microwave background. They see these warmer spots. They correspond to denser regions of the early universe, the place where you would expect large amounts of mass to come together. And then you calculate the number of hot spots versus the number of cold spots. And that tells you about what the mixture of big galaxies to small galaxies should be. Because those hot spots, big spots, are going to turn into big galaxies, while the less dense. But obviously it’s not a 1 to 1 right correlation because you can’t see like what that part of the cosmic microwave background radiation turned into. Yeah, it’s a different time. It’s you’re you’re seeing simultaneously one part of the universe that is older, that you’re seeing a different place. And so it’s like a statistically, you see one thing over here and that allows you to expect what you might see over on this other part of the sky. 

Pamela Gay [00:12:44] And we base a whole lot off of this, this general idea that the universe looked at, at a large enough scale and averaged is the same everywhere. So as long as you look at a big enough chunk, each big enough chunk will have the same amount of stuff in the same population of stuff in it. Just like grabbing a cup of sand at different points on the beach, you’re going to have the same distribution of grains. One might end up with a glass bubble in it. One might end up with a dead crab in it, right? Right. But more or less, you will have the same distribution in each cupful of universe as cup full of sand. 

Fraser Cain [00:13:28] It’s like fishing in Stardew Valley, right? You just keep fishing. Yeah, you’re going to get lots of the one kind of fish. And then every now and then you get the rare kind of fish, but you just keep at it and the statistics sort of pile up. So okay, so they had this sort of expectation like this based on the density over density regions of the early universe. This is the kind of structure, large scale structure of the universe that we should see. What did they say? 

Pamela Gay [00:13:57] Well, first I saw some really big things and they’re like, yeah, those are easy to see statistics. It’s all right. We’re still okay here. And then I kept looking. And they kept seeing really big stuff. 

Fraser Cain [00:14:12] Right? 

Pamela Gay [00:14:13] And it started to hit the point where I was just like, okay, so there is something clearly wrong with our theories or with what we expect a dark matter to be or with all of the above, because there are more large things than the cosmic microwave background seems able to support. So what is going on, right? And like literally the entire astronomical community had a moment of oh dear or excitement, pick one. But it was it was a moment of emotion for all of us. 

Fraser Cain [00:14:46] Right? But so I mean, when they saw them, it’s like these could be like a complete fluke that we just happened to see a part of the, you know, we happen to or. 

Pamela Gay [00:15:01] More of. 

Fraser Cain [00:15:01] Them kept happening. You know, we kept putting our hand in the water and we kept pulling out dead crabs like, yeah, you know, there’s a chance that you could keep pulling out dead crabs, but you’d expect to pull out just deeper seawater every now and then. Rocks or. Yeah, yeah, a little bit of seaweed. So. So then what could be going on that would give you these, these larger galaxies than expected? 

Pamela Gay [00:15:26] So people started reaching for all the different tools in the cosmological tool bag. There was the well, maybe dark matter had a different temperature than we thought. And cold dark matter is dead, which confused me deeply, because if you make it colder, then you end up with more big things. There was dark matter is not what we thought it was at all. Arguments. There was. Well, maybe there was just more stuff. Or maybe things aren’t where we thought because we’re not understanding the spectra, right? There was a whole lot of it can’t possibly be where we think we’re seeing things. And in a few cases, that was both the actual answer. And then the theorists with the big computers got involved and started rerunning their models with greater granularity. And this is one of the things that I’m really enjoying watching. What happens with everything from weather models to plate tectonics to cosmological models is it used to be we thought we were doing awesome when we modeled a galaxy with 10,000 points of matter to see how it evolved. And yeah. 

Fraser Cain [00:16:47] With a star can have one. A galaxy can have 100 billion stars. And. Right. Not to mention distribution of gas. 

Pamela Gay [00:16:55] And dust and dark matter. 

Fraser Cain [00:16:57] And dark matter and globular clusters and and rogue planets and black holes and influences from nearby galaxies. 

Pamela Gay [00:17:07] So theorists started doing the okay. So what happens if we increase the granularity of our models? What happens if we have a mix of hot and cold dark matter? What happens if and we started seeing some of the more wild explanations for what is causing dark energy in my opinion. Where we saw folks working on models for things like what if dark energy is a function of black holes? So there wasn’t dark energy prior to there being black holes and. We don’t know what the truth is, but one of the remarkable things that is happening is we are seeing more and more computer models capable of saying, yeah, I it looks like we can get there from here. It looks like the temperature on average that we thought was dark matter is actually the temperature of the dark matter. Just maybe it’s built up of more constituents. And and so you have the folks in the middle going, it’s not what we expected, but it doesn’t ruin our understanding of the universe. You have the folks that are jubilant on the other side going, the universe is totally different. Yeah, everything is bigger than it should be. It’s Texas, but in space they don’t actually say that. That’s right. It came into my head. Yeah. And then you have on the other side, the people are like, physics is weird. We have found weird physics. We are going to change our understanding of physics. And and I have to admit, I’m one of the people that is sitting on the sideline going. More data, please. Yeah. 

Fraser Cain [00:18:59] More data please. I mean, this is like, any one of those possibilities is exciting, right? Yeah. That, you know, these new computer simulations and I, you know, we did a couple stories on this on on Universe Today. Like, they like in the past, they’ve they’ve simulated fairly large chunks of the universe at a lower resolution. And instead they, they were able to make with some, some of the most powerful supercomputers on Earth, a very detailed simulation of a very small part of the universe, and found that the kinds of galaxies that are turning up in this data are, are fit within the the way the universe might have behaved. Or the models could be wrong. Right. Like like, you know, I mean, models are just models and. So maybe the. But at least you’re starting to make constraints like the most out there ideas you can sort of go, no, you know, dark matter can’t have this temperature. No, galaxies couldn’t have formed this. Like, you can start to put some constraints and then you have this playing space in between. And then as you say, right. It could be new physics, which is great. Like you imagine if there if that if there were new way like if dark matter is a combination of forces that if it is different than anyone ever expected that the universe was accelerating at different rate at different times, that there are different compositions of the universe are different, like, this is all great, this would all be wonderful. So however it turns out it’s so early that all you can do is just keep gathering information. It might be that we’re going to look at, you know, after the fifth g t ultra deep field has been released, the huge swaths of the sky have been mapped down. And the survey of galaxies is is really well understood. But we’re just we’re not there yet. And so it’s just it’s too early to say anything about anything ever. 

Pamela Gay [00:20:53] And what’s super cool though is folks are starting to look in all the different wavelengths. I mean, some wavelengths are just not going to be useful. Gamma rays. You can’t really study the early universe in gamma rays because the gamma rays have shifted to something else. But. We are in an age where we have meerkat coming online, where we have AI. With an unimaginable future, the Square Kilometer Array. We’re starting to build bigger and bigger optical systems. And the way things work in astronomy is you need some piece of data to say, it is worth it to give me time on this super expensive, limited resource telescope to explore this idea with. Without that fragment of data, you can’t get the time. Yeah, well, jethro’s t quite by accident is getting amazing results saying, yeah, we need to look at this a little bit closer, which is opening the door to use some of these other limited resource systems to look deeper and deeper and deeper and try and understand across the wavelengths just what was going on. And I am really looking forward to the suite of telescopes that are going to have ten years from now, where we start seeing early results from Square Kilometer Array, where we’re starting to get results from the Lsst, and where Jerry West has had enough time on orbit to start completing some of these deep fields and then doing the follow up observations. Right now, we’re not entirely sure what’s going on, other than we keep seeing really big things that seem to be in the first few hundred million years of the universe. Maybe we think, and they’re big. 

Fraser Cain [00:22:47] So I don’t know. Did you hear the most recent turn of the story? So, like, we’d been like ghosts. He finds galaxies that are too big too soon, and then. Yeah. And then. 

Pamela Gay [00:22:59] Then there is a correction to the distance. And then it was where. Then there was a no, wait. We have these other four Galaxy models. 

Fraser Cain [00:23:06] These are. 

Pamela Gay [00:23:06] Truly that far. 

Fraser Cain [00:23:07] Away. Yeah. And then yeah. So we’ve confirmed that’s exactly right. Yeah. And then and then the these models say no, actually these are perfectly well fit within the distribution data that you would expect. Nothing bizarre going on here. And the latest twist and turn is, is that some researchers went through and carefully examined the images and, and think that those galaxies may be 3 to 10 times more massive than originally believed. 

Pamela Gay [00:23:35] Holy expletive. Batman. 

Fraser Cain [00:23:38] Yeah. Yeah. Right. So. And there’s just like, it’s such a mess right now. It’s this exciting, wonderful ness with with just this sort of it’s like this renaissance of time of, of disc, of discovery with, you know, like you just this firehose of data. There’s just been, you know, barfed out onto the table, and astronomers are trying to pick through it and make sense of it. 

Pamela Gay [00:24:11] And the, the most data is basically through a carnival mirror, which is what’s partially making this so difficult. 

Fraser Cain [00:24:20] Yeah. Using gravitational lensing, which is could not be harder. 

Pamela Gay [00:24:25] No. 

Fraser Cain [00:24:25] Yeah. 

Pamela Gay [00:24:25] No, I mean, you can imagine we we talked a couple episodes back about the, the ultra diffuse low luminosity galaxies and the these are systems that are big and splurged out and have like 10 to 100 times fewer stars in our galaxy over the same volume space. And we can see that because we can directly image and image and image and image to see that splurge. Now, if you looked at this through a carnival mirror, it might get contracted in one direction, spread out in the other, and you’re trying to work backwards to figure out what that was. And all you know is how much light there is. Not with the original distribution of that light was. And so you might end up working out. Oh, that was just like a normal dwarf galaxy. Instead of this spread out volume of light, trying to reverse engineer geometry when you don’t totally understand the the gravity of the situation, by which I mean the literal gravity of that inconvenient galaxy. 

Fraser Cain [00:25:39] No pun intended. Yeah, yeah. And so I think, like right now we are right in the middle of one of these mysteries, and it’s one of these things that that five when we do our five year. What happened to those Impossible Galaxies episode. 

Pamela Gay [00:25:55] Yeah. 

Fraser Cain [00:25:56] In you know, around episode 1000, we will be able to come back around and go, oh, it turns out this is what it was. And now we have a really good concrete information. It turned out to be this, or it turned out to be that the Lambda CDM model has been completely overturned. And and now we’re in completely brand new territory. We are in the, you know, the unpleasant, not even unpleasant. Like the exciting thing for the quantum mechanics, right? Like nobody ordered quantum mechanics. Nobody does that. That’s how the universe worked and yet does deal with it. And, and this is where we could be going next. 

Pamela Gay [00:26:33] Very exciting. Since we added this episode to the calendar, the field has changed four times. 

Fraser Cain [00:26:40] Yes! Yeah. Yeah. Yeah. We planned this episode three months ago. 

Pamela Gay [00:26:46] Yeah. Yeah. And at that point, we knew that there were definitely four galaxies in the first few hundred million years that were incontrovertibly large. Yeah. And then everything else has happened since then. 

Fraser Cain [00:27:01] Yeah. So crazy. So fun. I love it. I can’t wait to see where this goes next. It’s just like to I always this analogy of like, you’re watching a sports game or like a mystery movie and you don’t know the outcome and you’re there for the for the game. You’re there for the for those exciting moments. And, and you don’t know how the whole thing is going to turn out. And we’re right now today in mid 2023. We are in this moment and I love it. So thank you, Pamela. 

Pamela Gay [00:27:35] And thank you. And thank you to everyone out in our audience who makes this show possible through your patronage over at Patreon.com. And all of you get ad free episodes as a benefit. We we can’t thank all of you during our episodes, but this week I would like to thank under a level, Gerhard Schweitzer or Schwarzer. I’m sorry. David Emmy Zang zero chill astrocytes. Paul F, Andrew Stephenson, Alex rain, Paul L Hayden, Sam Brooks and his mom, Bart. Flaherty, Brian. Kelby, Stephen. Coffee, Philip. Walker, Nate Detwiler, Benjamin Carrier, the air major, the lonely sand person, planetary. Louie. Zealand semansky, Sammy Raskin, John Drake, Gabriel Gelfand, Dean Glenn McDavid, Nyla Sean Matz, Benjamin Davies, ninja neck, Jason caduceus, Robert. Hundley. Kim. Barron, Paul. Esposito, Bob. Ezgi, Arthur. Latz. Hall, Ron. Thorson, Jordan. Turner, Hal. McKinney. Zebra. Lark, Bruno. Lutz, Jimmy. Berger, Ron. Rubin, McCarthy, Ian. Abdullah. Abdullah. Just MacDonald and Lee Harbaugh. And thank you all for tolerating my mispronunciation of your names week after week. 

Fraser Cain [00:29:06] Thanks, everyone, and we’ll see you next week. 

Pamela Gay [00:29:08] Bové. Astronomy cast is a joint product of the Universe Today and the Planetary Science Institute. Astronomy cast is released under a Creative Commons Attribution license. So love it, share it, and remix it, but please credit it to our hosts, Fraser Cain and Doctor Pamela Gay. You can get more information on today’s show topic on our website. Astronomy. Cars.com. This episode was brought to you. Thanks to our generous patrons on Patreon. If you want to help keep the show going, please consider joining our community at Patreon.com Slash Astronomy Cast. Not only do you help us pay our producers a fair wage, you will also get special access to content right in your inbox and invites to online events. We are so grateful to all of you who have joined our Patreon community already. Anyways, keep looking up. This has been Astronomy Cast.