Daniel and Kelly’s Extraordinary Universe - New discoveries in our cosmic neighborhood

Episode Date: October 1, 2020

Daniel and Jorge talk about a new massive blob of galaxies discovered right around the corner. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for ...privacy information.

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Starting point is 00:00:40 The Good Stuff podcast, Season 2, takes a deep look into One Tribe Foundation, a non-profit fighting suicide in the veteran community. September is National Suicide Prevention Month, so join host Jacob and Ashley Schick as they bring you to the front lines of One Tribe's mission. One Tribe, save my life twice. Welcome to Season 2 of The Good Stuff. to the Good Stuff podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast.
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Starting point is 00:01:43 Hey, Jorge, do you know what our cosmic address is? Yeah, it's one universe lane, isn't it? Well, that's where you can send us all your gifts of presents and bananas. That's how the aliens know where to find us, right? That's true. But I actually don't need a lot of bananas delivered in the mail. So let's not encourage people to send us any fresh fruit. No, no.
Starting point is 00:02:05 I think I know what you mean. Like our address, like in the universe, like we're here on Earth, around our star, about halfway down the Milky Way. Yeah, that's enough to get your mail delivered to your house. But like, what about the rest of our cosmic context? I mean, like, what's the equivalent of our city or zip code? Yeah. And it turns out that we're part of a cluster called the local group. Sounds local.
Starting point is 00:02:26 And then zooming out a little bit, we're in the suburbs of an even bigger cluster called Verga. And then part of a super cluster of 100,000 galaxies called Lenakia. Wow. And then? You know, that's actually about as far as we've matched. Wait, we don't know where we live exactly in the universe? We don't know. So if you want to order alien bananas, you just got to put a question mark. Get a throw up a flare.
Starting point is 00:02:56 Hi, I'm Horhammy cartoonist and the creator of PhD comics. Hi, I'm Daniel. I'm a particle physicist, and I don't like Earth bananas, but I'd be willing to try alien bananas. Oh, really? Huh. How do you know they're not going to be worse? You don't know, but that's the joy of exploration. I want to land on a new planet to see the new kinds of life, the new kinds of animals, and critters and taste any new potentially delicious fruits. Well, you're welcome to be humanity's taster, I guess, to make sure it's all right. Somebody's got to do it. I'll probably come down with the alien banana flu.
Starting point is 00:03:39 But welcome to our podcast, Daniel and Jorge Explain the Universe, a production of IHeart Radio. In which we don't take any actual trips out into the universe, but a mental journey through all the amazing questions and discoveries, all the things science has figured out and the things that science is still working. on. We think that curiosity belongs to everybody and that your questions are as fascinating and as important as those that scientists are working on right now. Yeah, because it is a huge universe out there with a lot of places to explore and a lot of things to discover. And a big question is, how do we fit into all of this? What is our place in the universe and how do we fit into this giant cosmic ballet of stars and galaxies and dust? And it's sort of an extension of exploration that humans have been doing basically forever since we wondered what was over that hill
Starting point is 00:04:33 what's past that mountain what's over that ocean and modern day explorers might wonder like well is there anything left for me to look for thanks to google earth and satellite technology we basically know where all the mountains are and all the little islands you can name after your chihuahua but it turns out there's a lot of exploration left to do yeah is there an equivalent of google universe Google, get on it. Not yet. It's mostly a big question mark. But you can look at maps of our cosmic neighborhood to see what's around us and what's nearby.
Starting point is 00:05:06 If you just Google large-scale structures of the universe. Wow. Does it tell you how much each galaxy is worth? Can you figure out the per square lightier value? You know, even just our solar system is worth like a gazillion dollars because of all the platinum and gold and stuff that you can find in asteroids. Oh, wow. So it's basically just infinite. Wow.
Starting point is 00:05:25 Well, we are still learning. about the basics of where we are in the universe and what's kind of around this. And so a big question is, you know, what can we find? What interesting things are there in our very own neighborhood here in the universe? And it's not something that we can easily explore in person. In the old days of exploration, you would hop in a ship and you would land on foreign shores and you would wonder who else was living there and what kind of fruits did they enjoy. But these days, it's not so easy.
Starting point is 00:05:54 The distances are vast. The technology is still so primitive, but we have other ways of exploring the universe. You mean we don't have those warp drives and teleportation devices yet? Well, you know, I sent them to the Daniel and Jorge engineering department, so I'm just waiting for the prototype to come back. I'll ask the engineer in our team here. But yeah, you're right.
Starting point is 00:06:14 It is kind of interesting that we have to explore the universe from here, from Earth, using telescopes. We can't actually, like, go out that far because some of the things that we can see are hundreds or millions of light years away. Like pretty much we might never see them in person. That's right. Most of these things we will never see in person. And most of these things that we're looking at,
Starting point is 00:06:35 they don't exist right now the way that we are seeing them, right? We are seeing old light that comes to us from them. So what's actually happening now out there is not what we are seeing. Yeah. So astronomers are out there looking and exploring and checking out what's around us. And recently there's been an incredible, discovery just this past summer. Astronomer has discovered a whole new thing pretty close to our corner of the universe here and it's huge. It's basically the biggest thing anybody has ever
Starting point is 00:07:07 found and it's shockingly large and shockingly close. It's basically a literal mind explode. So today on the podcast we'll be asking the question. What is the South Pole wall. And why did they give it such a ridiculous name? South, but yeah, it's a little confusing because is it a pole or is it a wall? Is it a wall of poles? Is it a wall around the South Pole?
Starting point is 00:07:36 I guess it's South, but South relative to who? Well, you have a very northern bias, right? You tend to view the Earth is up. North is up. And so maybe that gives you a clue. I was born in the equator, so Daniel, I'm pretty agnostic, I think. Maybe this time you can rag on astrophysicists
Starting point is 00:07:53 and how they name things. And us particle physicists can get a break for a week. For once. Yeah. And also, who's paying for this wall, Daniel? The aliens are definitely paying for the wall. Yeah, with the tariffs.
Starting point is 00:08:07 But yeah, so they discovered something huge and enormous. I mean, like you said, it's the biggest thing pretty much ever discovered. Is that true? Yeah, it's in the top five biggest things we know about in the universe. And of the top five,
Starting point is 00:08:21 it's the closest one. So it's really kind of amazing that we haven't seen this before, that we didn't even know about it before. It really makes me feel like, you know, cartographers in the 1500s drawing maps of the earth and like leaving out America. You know, like how could they be so ignorant of like an enormous continent that's honestly not that far away? It'd be like discovering a whole wall of poles in your backyard and you're like, where did that come from? That's right. I didn't order this online. Yeah. Yeah. So it's a new discovery. It's huge, it's very close, but we're wondering how many people out there and know about this South Pole Wall and whether it was discovered recently.
Starting point is 00:09:02 So as usual, Daniel went out there and asked people on the Internet if they knew what is the South Pole Wall. So thanks to everybody who volunteered to share their baseless and uninformed speculation with us for our podcast. And if you would like to be a victim for our future podcast to share your unprepared thoughts on difficult questions in physical. please write to us to questions at danielanhorpe.com think about it for a second do you know what the south pole wall is here's what people had to say does that have something to do with flat earther theory it's a wall a man-made wall built around south pole to stop animals or intruders from coming in as a way to preserve the south pole maybe it's some sort of electromagnetic barrier not just an obvious structure something to do with uh like a magnetic, like the Earth's magnetic field, some sort of barrier for particles in the sun, from the sun. Maybe it's related somehow to the, like, Aurora Borealis and Southern Lights. The South Pole Wall is a ice alt formation that is incredibly difficult to traverse on foot or sled or with dogs. I have no idea.
Starting point is 00:10:26 I am guessing that it is a wall, either physical or metaphorical, located in the South Pole. The first thing that comes into mind is a big wall of ice in the South Pole, like the one from Game of Thrones. I'm not sure, but I believe there are some, I don't know if they're called caverns or cliffs or something like that, but I believe there's some impediment in our way to get to the, to travel freely to the South Pole where the ice is. is all right it sounds like nobody knew well i think this is a real commentary on the name of this thing right because everybody keyed in on south pole and wall right and i like i like how somebody said it was like game of thrones although that wall was in the north that's right maybe it's the equivalent maybe it's for like the penguin zombies well we physicists we do like having symmetry
Starting point is 00:11:15 in the universe so if there's going to be a wall in the north there should be a wall in the south because otherwise you got to ask why what's special about north Yeah, winter is coming. Is there another version of our universe out there in the multiverse in which summer is coming? Well, technically, if it's a South Pole wall, it would come in our summer, which is winter for them. The beauty and power of symmetry once again displayed. I guess maybe the takeaway here is that not a lot of people had heard of it, which means it didn't make the news that much, maybe. That's right.
Starting point is 00:11:47 Most of our listeners are pretty up on the cosmic news here. Yeah, I think it just didn't fall into people's brains. It's an incredible discovery. It's something that's fascinating. It's something that tells us about where we live in the universe. But it doesn't really actually change your day-to-day life. So maybe people just heard about it and filed it away. But honestly, I think we should pin most of the blame on the name of this thing.
Starting point is 00:12:10 Oh, wow. I can't disagree with you more, Daniel, about the naming of things. Finally, we're agreeing about how to name things. All right, let's not keep people in suspense here. So what is the South Pole wall, Daniel, and when was it discovered? So the South Pole wall is an incredibly huge, an immensely vast, gargantuan wall of galaxies. Remember that galaxies are not just sprinkled everywhere through space. Our Earth goes around our sun, which is the core of our solar system, which is one of many solar systems in our galaxy.
Starting point is 00:12:45 But those galaxies are not just everywhere in space sprinkled randomly. They tend to clump together into clusters of galaxies. galaxies. And those clusters of galaxies form structures we call superclusters. And then those super clusters are not just sprinkled everywhere. They tend to form these enormous structures, these walls, these filaments, these sheets that surround incredible voids in which there are no stars, no galaxies, no planets, no people, no podcasts. Yeah, it's weird to think of space being not random. You know what I mean like we're used to looking at the night sky and seeing stars kind of sprinkled kind of randomly and evenly but actually the universe has a lot of structure like it has a lot of things in it like everything's
Starting point is 00:13:31 kind of organized in the way that's right things are organized and it's gravity that's doing the organizing gravity is very gently but very gradually pulling things together and clumping them right and it's kind of incredible that gravity is a thing doing this job because of all the forces we are aware of the strong force, the weak force, electromagnetism, gravity. Gravity is the weakest and not by a little bit, but like by tens of orders of magnitude. But it's also the only one that can't be like balanced out. Electromagnetism can be neutralized with positive and negative forces, but gravity always pulls. It can't push. So eventually everything else gets balanced out is just gravity left over to sweep stuff together into stars and planets and galaxies
Starting point is 00:14:16 and superclusters, and then these incredibly immense voids and walls and filaments. And that's essentially where the exploration is today, is figuring out like, where is our cluster and our supercluster in this larger structure? What's around us? Right. Yeah. And what's kind of cool, too, is that these giant, you know, super ginormous structures, they're all kind of evidence of the quantum fluctuations, right?
Starting point is 00:14:42 At the very beginning of the universe, right? there's sort of like the wrinkles or the fingerprint of quantum randomness and structure that was in the early universe. That's exactly right. Gravity has essentially just exaggerated initial little over densities. If you had only gravity and the universe was totally smooth, you wouldn't get any sort of structure at all because gravity would pull equally on everything in all directions and you wouldn't get any clumping. You need some sort of initial clumping to get things started and form this run. runaway effect where gravity makes things heavier and then pulls harder and then makes things heavier, which pulls harder. And you're right that in the very beginning, what this comes from are little tiny quantum
Starting point is 00:15:25 fluctuations in the very first moments of the universe. And basically, everything's been derivative from that. It's like we had one idea very early on, sketched a doodle, and everything else is just derived from that. Yeah. And it's amazing to think that you can go from like a quantum fluctuation to something that huge. It's sort of like, you know, like a little baby scar that you had as a baby, you still have it as an adult.
Starting point is 00:15:48 And let's give people a sense for like how big we're talking about. These structures are like billions of light years wide. These are not little things. There's not like one galaxy, two galaxies. Remember, each galaxy already is an incredibly enormous thing. But we're talking about bubbles and sheets that are billions of light years on a side. And that all comes from tiny quantum fluctuations, expanded rapid, during inflation. Wow. Yeah, because, you know, I guess like one galaxy is 100,000 light years. And so if you
Starting point is 00:16:19 put like thousands of them together, then it's literally billions of light years. It's billions of light years. Meaning if you're going at the speed of light, it still takes you a billion years to go from one side to the other. And so you can imagine the whole universe is sort of like a big pile of bubbles, like a big quantum foam that was inflated from the early universe to this incredibly vast quantum foam. And we've recently discovered that we're essentially living on the edge of one of those bubbles. And we're now looking around us. We're like, oh, look, there's a bubble over there. There's a bubble over there. But we're really just beginning to map the universe, to understand what is our cosmic neighborhood. We're seeing edges of bubbles here and bubbles merging over there.
Starting point is 00:17:02 And so it's like, it's early days, you know. We've only just begun to explore. Yeah. And so tell me about this wall that we just found, this wall, the South Pole wall, You said it's ginormous. When you say ginormous, is that the technical term or is there a number associated? The technical term actually is Hugh Jungus, but this one is a billion and a half light years wide, right? So you shoot a photon, you press the button on your laser on one side of the thing, you wait a billion and a half years before it crosses to the other side. And that's only the part of it that we've seen so far. It could go on more.
Starting point is 00:17:39 Yeah. Astronomers are not even sure that we've seen all of it. Wow. So it's a structure of galaxies, basically, right? It's not like a row of stars. It's like a row of galaxies. And they're all sort of like sprinkled in a wall or what's going on? That's right. It's actually a row of clusters of galaxies. A clusters of galaxies are grouped together. They're gravitationally bound. There's enough gravity between galaxies to sort of hold them together into objects. That's what we call them a cluster. We don't just like, artificially draw a line and say, this is a cluster. That's a cluster. We look for things that are holding themselves together gravitationally. So this is a wall of clusters of galaxies. And we call it a wall because it's much wider and longer than it is thick. Sort of like our galaxy, right? Our galaxy is flat. It's like 100,000 light years across and a thousand light years thick. And these things have sort of similar dimensions. They're much, much wider and longer than they are thick. So we call them a wall. Now, do you group them together because they're close to each other or because they're actually kind of gravitationally affecting each other or bound together?
Starting point is 00:18:47 They are gravitationally holding themselves together. Remember that the whole universe is expanding. Everything is moving away from everything else. That's because space between objects is getting bigger. We don't understand it. It's this thing called dark energy that's just inflating all of space and increasing the distances between everything. But if stuff is near enough to each other and has,
Starting point is 00:19:08 has enough mass, it can resist that. It can be gravitationally bound, like our solar system. Dark energy is increasing the space between the earth and the sun, but gravity of the sun holds the earth in place so that distance doesn't change. So our solar system is gravitationally bound. Our galaxy is gravitationally bound. It's small enough and compact enough that on that scale, gravity wins. And that's true also on the scale of clusters. And it's sort of true on the scale the super clusters, clusters of clusters. People argue about whether they're actually gravitationally bound. Are they going to hold together in the long-term future of the universe, or is dark energy going to win and tear them apart? That's sort of on the edge. Right. Because I guess if
Starting point is 00:19:52 expansion is fast enough or big enough, it would even rip our solar system. But I guess we're lucky that it's not. That's right. We're lucky that it's not. But we're living in a fascinating moment in the universe where gravity has had time to build galaxies and clusters. And now, super clusters have sort of formed and may be gravitationally bound, but it's not clear if gravity will have time to build those together and really hold them together and then build super duper clusters or whether dark energy will tear them apart. So we're living at this fascinating moment in the history of the universe. That's why there is a maximum size to an object in the universe, because any bigger than that, gravity hasn't had time to sort of pull it together. And so we're really
Starting point is 00:20:33 looking at the biggest things in the universe. It's sort of incredible. All right. So we found this giant wall. And so a big question I have is, how did we find it? And why didn't we see this earlier if it's so big? So let's get into that. But first, let's take a quick break. kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal, glass.
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Starting point is 00:21:49 on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Well, wait a minute, Sam. Maybe her boyfriend's just. looking for extra credit. Well, Dakota, it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now, hold up. Isn't that against school
Starting point is 00:22:20 policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor and they're the same age. And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I don't write songs. God write songs. I take dictation.
Starting point is 00:22:51 I didn't even know you've been a pastor for over 10 years. I think culture is any space that you live in that develops you. On a recent episode of Culture Raises Us podcast, I sat down with Warren Campbell, Grammy-winning producer, pastor, and music executive to talk about the beats, the business, and the legacy behind some of the biggest names in gospel, R&B, and hip-hop. This is like watching Michael Jackson talk about thoroughly before it happened. Was there a particular moment where you realize just how instrumental music culture was to shaping all of our global ecosystem?
Starting point is 00:23:22 I was eight years old, and the Motown 25 special came on. And all the great Motown artists, Marvin, Stevie Wonder, Temptations, Diana. From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that drives it. Listen to Culture raises us on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. All right, Daniel, we're talking about the South Pole Wall, which is, I guess, is that where the anti-Santa Claus lives? Is that defense that it put on its elf village? That's right. It's his first line of defense against folks coming and trying to steal their Christmas presents early.
Starting point is 00:24:10 He's not as, or she's not as jolly as the North Pole Santa Claus. No, there's South Pole boiling oil and there's archery and there's all sorts of stuff. Just leave them alone. But anyways, they found this summer a giant wall of galaxies called the South Pole Wall. And it's huge. It's one and a half billion light. years wide. And Daniel, this seems like a big thing that we should have seen earlier, but we didn't. So I guess what's the history of finding this? How do we find it? And why didn't we see it before?
Starting point is 00:24:39 We didn't see it before because it's not easy to spot. We can't actually see it very well because there's something in the way. And that's the rest of our galaxy. If you look out into the sky, mostly you're seeing stars and those stars are other stars in our galaxy. But remember, the galaxy is much wider than it is thick. So in most directions, you're looking out through a little bit of our galaxy and then out into deep space where you can see other galaxies and stuff. But if you look in just the right direction, then you're looking through the galaxy. And on a really dark night, you can see this.
Starting point is 00:25:14 You can see the Milky Way, which is the plane of the rest of the galaxy. And it looks much brighter and sort of more smeared out than individual stars because it's a huge number of stars that are further away. They're on the other side of the Milky Way. And so they sort of add up to this milky spread. And it's hard to see things on the other side of this plane of the Milky Way because there are so many stars and gas and dust in our way. Yeah, we're in the way of our view, kind of like the back of your head. Yeah, the rest of the galaxy.
Starting point is 00:25:44 And so they called it the South Pole wall because if you're standing on Earth, it's sort of in the direction that the South Pole points. That is the South Pole of Earth sort of points. towards the center of the galaxy. Not exactly, but, you know, close enough. Close enough for astronomical naming committees, apparently. Yeah. Yeah, it is pretty amazing to think that we can see the Milky Way, right? I mean, it looks like a fuzzy cloud, but it really, it's like millions of stars,
Starting point is 00:26:12 kind of all kind of joining their light together and causing this glow. Yeah, it's billions of stars, right? The Milky Way has more than 100 billion stars in it. And the center of the Milky Way is where most of them are, and there's also a lot of gas and dust. So it's just very difficult to see through the center of the Milky Way. Astronomers call this whole region of the sky the zone of avoidance.
Starting point is 00:26:34 It sounds like something from a video game, but it basically means look somewhere else because this part is hard. Right. Don't look here. You're not going to be able to see much. Yeah. And so we can't actually see most of the South Pole wall in the visible light. We can't just like look at it and say, oh, there's a galaxy, there's a galaxy, there's a galaxy.
Starting point is 00:26:52 Otherwise, we would have spotted it earlier. You know, it was like in the 1980s, people started to understand that we could make a huge 3D map of our universe and that it had interesting things to look at. And that's when we discovered the first of these voids and walls. And so now it's, you know, 40 years later, we're finally figuring out one of the biggest structures was hiding right behind the bulge of the Milky Way. It is sort of fascinating that, you know, from our little point on Earth, just sitting in this spherical ball and looking out at this. stars, we can get a 3D view of things, right? Because when you look at the night sky, it looks kind of like 2D, like all the stars are painted on the ceiling. But somehow we're able to get a 3D view of what's going on out there to the point where, you know, we can make out these super
Starting point is 00:27:40 clustered structures. Yeah, it's incredible because of course, you're right, we do see a 2D image, right? We can't resolve distance. We don't know necessarily how far a star is. And there's ambiguity there. When you look at one individual star, you don't know, is it super bright but very far away or not that bright and kind of close up? So for a long time, that was a big puzzle in astronomy is how to measure the distance to stars. We had a whole fun podcast episode just on that topic. And it turns out that it depends on how far away it is. If it's really close by, you can use the equivalent of sort of like opening one eye and closing the other one and seeing how the image changes to see how far away it is as the earth goes around the sun, you get two
Starting point is 00:28:25 images of the star. And if it's further away, you have to rely on these super clever little stars, these variable stars whose brightness is connected to how fast they pulse. And then if they're really far away, then you have to use type 1A supernova, which is sort of a standard candle. We know how bright they are because the physics constrains them to only be a certain brightness. And so we can tell how far away they are. So we have this sort of cosmic distance. But that only works for things we can see. Yeah. So the Milky Wake is kind of standing in the way of a huge part of our field of view.
Starting point is 00:28:59 It's blocking it. But somehow we were able to see through this to find this South Pole wall. So how do we look through the Milky Way? Well, again, the answer is gravity. Gravity is like the most important thing astronomically. It basically controls the whole universe. And in this case, what we did is we measured how fast some galaxies were moving and in what direction to make a sort of cosmic map of the flow of galaxies, and then we use that to figure
Starting point is 00:29:27 out like, well, where is there stuff? Because gravity affects how things move. So we started from understanding how galaxies are flowing, and then we looked for sort of like blobs, like discontinuities, like, oh, everything is clustering over here. There must be something there. Or these guys are flowing faster than we expected, so they must be pulled on by something. From the velocity of galaxies, you can infer where the mass is. Oh. But wait, are galaxies moving that fast that we as humans in such a short period of time can tell if they're moving?
Starting point is 00:30:01 Because like if I look at the stars, they don't look like they're moving. That's right. We are not watching galaxies move and like clocking them. It's not like Usain Bolt where we measure a distance and measure time and then use that to measure the velocity. Instead, we're looking at the light from those stars. And we're seeing how the light from the stars is shifted in frequency. Because like the Doppler effect, if something is moving away from you, then light from it will get shifted to longer wavelengths so it's stretched out.
Starting point is 00:30:28 If something is moving towards you, light from it will get shifted to shorter wavelengths to get blue shifted. And so we can measure the light from these stars. And we can see, has it been shifted away from what we expect? Because we know what the light from these stars from these galaxies should look like because stars around the universe are all the same. they emit from hydrogen and from sodium in various lines. We can see those lines get shifted so we can measure the velocity of all of these galaxies. So we have this huge catalog of thousands of thousands of galaxies, and we know in which direction they're moving.
Starting point is 00:31:01 But wait, I thought the shifting of light only works if it's moving away or towards you. How do you tell if it's moving to the right or to the left or up or down? That's true. The redshift and blue shift measures the velocity along a line from us to them, It's sort of the radial velocity. And so you have to use other tricks to try to sort of guess and construct from the motion of all the galaxies nearby what the sort of 3D map is. But you're right. We don't really know a lot about the sort of transverse motion of these galaxies.
Starting point is 00:31:32 So everything we know is just from that velocity towards or away from us. That's right. And we're sort of guessing about everything else. Not 100% guessing. You can see these things moving over short periods of time. So you have some idea. but they are really far away. So it's very difficult to measure those distances.
Starting point is 00:31:49 And also, how do we know where they are, how far away they are? Don't we need like a supernova to happen in them before we know? Or do we have supernova from each of those thousands of galaxies? We have supernova that go out really, really far. That's the nice thing about type 1A supernova is they're super bright and they're basically in every galaxy. But we don't have one. We haven't seen one necessarily in every galaxy.
Starting point is 00:32:12 But we have ideas for where other things are. so we can place them sort of in a ladder. And we have the most information about the closest things. And so that's why we're starting to map the structure of the universe and we're beginning from the nearby neighborhood. That's where we can see, for example, still sephids in some of these galaxies and type one of a supernova. We definitely have the most information about the local neighborhood.
Starting point is 00:32:33 All right. So then step us through. How do we find this South Pole wall? Did we, you know, gain some sort of new trick to look through the Milky Way? Or we just got better at it and suddenly it popped. It's just sort of like being careful and finally analyzing the hard bit of the data. You know, if you're doing science, you get a bunch of data. And the first thing you do is you eat the ice cream off the top, right?
Starting point is 00:32:55 And you say, well, here's the easy question to answer. The most exciting one, you do that. And people have found cool stuff. They found the Sloan Great Wall, which is as big as the South Pole wall, but it's further away. And it's easier to spot. So they found other structures. But then people started to get more comprehensive about their search. And so they looked through sort of some gaps and they noticed there was a gap in our cosmic
Starting point is 00:33:19 neighborhood where we didn't understand what was going on. That's because it was behind this zone of avoidance. So they decided to look like, well, what is there? And they combined data from a bunch of different surveys, Sloan Digital Sky Survey and lots of other surveys to make one sort of mega database of all the galaxies called cosmic flows. And so they analyzed this hard bit and they noticed that galaxies, between us and this region were moving away from us faster than you would expect from just dark energy. And the galaxies past this region were moving away from us more slowly than you would expect.
Starting point is 00:33:57 And so that suggests right there that there's some like big blob of something. Moving together. There's some gravity there holding it together, pulling on galaxies between us and this blob and slowing down galaxies that are past the blob. we saw like this giant like if you're looking at it on a radar you would see like a like a flock of birds kind of all moving together away from us yeah exactly so you put together where all these galaxies are and how fast they're moving away from us and the only way to explain the velocities of these galaxies they call this peculiar velocity velocity other than the velocity of the expansion of the universe peculiar the only way to explain this peculiar velocity such a quaint term peculiar as in like local You know, like is in our velocity and not somebody else's. They didn't want to go with weird or... Or local velocity or something.
Starting point is 00:34:49 Anyway, the only way to explain this peculiar velocity is to say, well, there must be something big there, some new source of gravity. And this is not the first time that we've used gravity to deduce the presence of something. Remember our podcast episode about The Great Attractor? That's some other, like, incredible source of gravity that's similarly tugging on stuff and changing the peculiar velocities so we know that there must be something there. Wow.
Starting point is 00:35:15 All right, so we saw something big out there, but can we see it directly? Like, can we see the glow from it or we can only see the gravity of it? We can only see the gravity for most of it. Little bits of it sort of peek out the sides of the zone of avoidance, then you can spot it.
Starting point is 00:35:33 And then they actually went back through old surveys to say, shouldn't we have seen this before? And it turns out that you can see, sort of edges of it in previous astronomical surveys. So people have been sort of like known to look for it, had been paying more attention. They could have discovered this like 10, 20 years ago. Really? Yeah.
Starting point is 00:35:52 They saw like the edges of it. The edges of it sort of peek out past the zone of avoidance. The bulk of it, though, is basically invisible to us in terms of electromagnetic radiation. We can't see it via radio waves or infrared or anything because it has to pass through the galaxy. So it's only gravitational information that we have about. most of it. But that's pretty good. Like if you look up this paper, they have a pretty good 3D map of the density of this thing that shows you like where the galaxies are and where they aren't. It's a fascinating structure.
Starting point is 00:36:22 All right. Let's get into the shape of this South Pole wall and why it's important that we found it. But first, let's take another quick break. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal, glass. The injured were being loaded into ambulances. Just a chaotic, chaotic scene.
Starting point is 00:37:06 In its wake, a new kind of enemy emerged, and it was here to. to stay. Terrorism. Law and order criminal justice system is back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts.
Starting point is 00:37:37 My boyfriend's professor is way too friendly. and now I'm seriously suspicious. Well, wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot.
Starting point is 00:37:54 He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now, hold up. Isn't that against school policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor,
Starting point is 00:38:06 and they're the same age. And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast
Starting point is 00:38:24 on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I don't write songs. God write songs. I take dictation. I didn't even know you've been a pastor for over 10 years. I think culture is any space that you live in that develops you. On a recent episode of Culture Raises Us podcast, I sat down with Warren Campbell, Grammy-winning producer, pastor, and music executive to talk about the beats, the business,
Starting point is 00:38:47 and the legacy behind some of the biggest names in gospel, R&B, and hip-hop. This is like watching Michael Jackson talk about Thurley before it happened. Was there a particular moment where you realize just how instrumental music culture was to shaping all of our global ecosystem? I was eight years old, and the Motown-25 special came on, and all the great Motown artists, Marvin, Stevie Wonder, Temptations, Diana Raw. From Mary Mary to Jennifer Hudson, we get into the soul of the music and the purpose that drives it. Listen to Culture raises us on the iHeart Radio app, Apple Podcasts, or wherever you get your podcasts.
Starting point is 00:39:30 All right, Daniel, we're talking about the wall, south, the southern wall, that the first man built, or the first aliens built, I guess, to keep out the alien zombies. No, I'm just kidding. We found a giant galactic structure or a structure of galaxies kind of pointing if you look south of the earth
Starting point is 00:39:50 towards the South Pole and keep going past the Milky Way out there in space. It's huge. It's one and a half billion light years wide. And what does it look like, Daniel? Is it like literally a wall or like a sheet or just like a giant lump? This looks like a
Starting point is 00:40:06 giant cosmic banana. You're just saying that, Daniel. I'm not just saying that. It really does look like a huge banana. What do you mean? Like it's curved? If you look at this thing from the paper, it's sort of long and narrow. It even has like a little thing sticking up at the top that could be like, you know,
Starting point is 00:40:24 where it was peeled off the giant cosmic banana tree. Oh, man. So are you saying it looks delicious is what you're saying? I'm saying you've got to be hungry to eat this thing as wow. It's huge. And it has a lot of potassium. A lot. I'm not joking that it looks like a banana, but, you know, it's sort of like staring at clouds.
Starting point is 00:40:41 You can see whatever shape you want. And so I guess I just had bananas on the brain. In my mind, it's not as much of a wall. It is sort of like a vast tube, but it's definitely big. And it's incredible because it's also telling us not just where the stuff is that we can see, where the galaxies and the stars and maybe the aliens and their bananas are, it's also a map of the dark matter. What?
Starting point is 00:41:04 What do you mean? Well, remember that stuff in the universe, is not sprinkled out randomly, right? It's clumped together based on the gravitational over densities from the early universe. But most of the stuff in the universe is not the kind of stuff that we can see. It's dark matter. There's five times as much invisible, mysterious matter that's affected by gravity as the kind of matter that we're familiar with.
Starting point is 00:41:27 And the kinds of matter that we can see tend to line up with the dark matter. Both of them are affected by gravity and they pull on each other. So actually, when you look at stars in the sky, they're telling you where the dark matter is, because dark matter has created these like gravitational wells for stars and galaxies to fall into and to form. So the light matter, the normal matter, is sort of like lights showing you where the dark matter is. I mean, but we think, right? Like you're assuming that where there are stars, there is dark matter. I mean, you're assuming like it's the same kind of concentration or ratio between dark matter. matter and regular matter as we have.
Starting point is 00:42:07 Yes. And that's something that we've seen. We've measured in lots of different galaxies. And we see some variation there. There are some galaxies with more dark matter or less dark matter. And we don't fully understand that at all. But roughly we can say that there's a five to one relationship between dark matter and normal matter.
Starting point is 00:42:23 And certainly on distances this large, enormous super cluster size structures, we expect the dark matter to have formed these structures. Like they just would not have formed without the dark matter. You run a simulation in the universe without the dark matter. You just don't get structures like this this early in the universe. I feel like you're almost telling me that basically most of the universe is dark matter and it's clumping and doing its own thing. And really the stars, the bright stuff, us.
Starting point is 00:42:51 We're really just kind of like the bling, you know? Like we're just here to tell everyone where the dark matter is. Yeah, we're like those birds that ride on the back of rhinoceroses and sort of like pick the worms off of them. That's us. Yeah. I mean, call us the bling. Call us the worm-eating birds, whatever you like.
Starting point is 00:43:06 We're the frosting on the cupcake. Yeah, kind of, right? I mean, when you talk about the structure of the universe, it's really the dark matter structure. We're just hanging on. Yeah, we call it normal matter because we're used to it, but it's actually pretty unusual in the universe. It's just 5% of the energy in the universe is devoted to making me and you and cosmic bananas. So that's why it's fascinating to sort of use this light matter, this luminous matter, to tell us what's actually going on in the universe. And gravity is really the key there. It tells us where the dark matter is.
Starting point is 00:43:39 It's also telling us about the balance between the dark matter holding stuff together and dark energy trying to tear it apart. Right. Except that here we can't actually see the galaxies and the stars and the light, right? Like, we can only see the gravity, which means maybe this whole wall is just a giant wall of dark matter. You don't really know, right? That's true. We don't really know. Although on the bits of it that we do see the edges of the banana that stick out, past the zone of avoidance, we can't see luminous stars there. So it would be pretty weird to find a massive dark matter wall, but that would be pretty awesome. And give us a sense of how big this thing is, like how many galaxies are in this giant wall or like how many stars, do you have a sense?
Starting point is 00:44:21 It's trillions and trillions of stars, you know, it's thousands and thousands of galaxies. And each galaxy has billions of stars. And we don't know how big this thing is. The thing that's incredible to me is that before we discovered this, we had sort of a gap in our understanding of the cosmic neighborhood right around this spot, right? And people were like, well, we don't know what's there, probably nothing interesting. And then they found this great wall, and it's basically completely fills that gap. You know, it's like it couldn't have been any bigger. You know, there's like a little spot you haven't checked, and you open up the door, and it turns out it's totally full of stuff. We have this giant gap that looks like a banana, but we don't know
Starting point is 00:45:01 what's inside. Oh, wait, it is a giant banana. It's a giant banana. And, you know, it's really important that we understand the shape of the universe around us. It really is telling us about how the universe was formed because it tells us about how this structure is made and is telling us about the future of the universe. It's telling us, is dark matter going to win and hold this stuff together? Is dark energy going to win and tear this stuff apart? You know, we think about this stuff on really long time scales, billions of years, but it's really sort of frothing and dynamical. This is sort of like if you watch froth forming or water boiling, but you just watch the first like two milliseconds of the movie. We're basically two milliseconds into the movie of the universe
Starting point is 00:45:44 of this frothing bubbling boil, trying to understand the forces at play. Wow. You mean like we don't know who's going to win at the end, but we're still figuring that out, looking at the things around this. Yeah, well, we know that dark energy, if it continues as it has been, is going to eventually tear things apart. But we don't know where those fractures are going to happen exactly. Like, how much will gravity get to clump together to form structures that will be impervious to dark energy? And then dark energy will just increase the distance between them. How big will those objects be? We don't really know. It depends sort of delicately on how much dark matter and how much dark energy there is. You mean like, well, the universe is expanding, but the stuff in it could
Starting point is 00:46:23 hold together potentially? The stuff in it probably will hold together. Our galaxy will hold together. Our cluster of galaxies probably will hold together. Will our supercluster survive or be torn apart by dark energy? We don't really know. Will these walls and filaments be pulled apart? Are they even gravitationally held together today or are they just sort of near each other? These are the questions we don't know the answer to. It's like a cosmic battle between the two greatest forces in the universe and we're basically right in the middle of it. We're just here on the back of the the rhinoceros picking worms. Looking at it, like eating popcorn, but instead of popcorn, it's worms.
Starting point is 00:46:59 That's right. Hey, look, this worm looks like a banana. All right. Well, it's pretty amazing that we are still discovering things that are that big. Like, you know, if I look at into the sky, how big is this giant wall, Daniel? Is it like an inch or like a centimeter or like a whole foot? As a fraction of the night sky, if you held, I think, a banana at arm's length, it's about that big. No, that's too much of a coincidence, Daniel.
Starting point is 00:47:26 It goes from the constellation Perseus in the northern hemisphere to the constellation Apus. I can't pronounce this one in the far south. So it is really pretty big. And the incredible thing is that it's twice as close as the Sloan Great Wall, right? The Sloan Great Wall, just as big discovered decades ago. This thing is twice as close, which should make it more obvious. But, you know, there's just so much we still don't know
Starting point is 00:47:50 about the pretty local large-scale structure. in sort of the grand scheme of things in our neighborhood. Wow, that's amazing. It's almost like we're, you know, explorers only a thousand years ago. We didn't know that America was there or, you know, Australia was there probably. I know how many incredible opportunities were there to discover things. You just had to hop in a boat and sail for a few days. If you had known where to look, discovery is easy.
Starting point is 00:48:14 And that's the situation we're in today. We're looking around us and we just don't know what's out there. There could be incredible mind-blowing surprises. If we just look a little further or look in the places that have been hard to look at so far, there are definitely surprises out there. And then remember, we've only mapped a tiny little dot of the universe. When we talk about like our solar system being a tiny fraction of the Milky Way, which is a tiny fraction of our cluster,
Starting point is 00:48:39 if you look out even further, it just goes on and on and on. And what we've mapped is a tiny fraction of just the observable universe. So most of it is a huge cosmic question. Right. It could be maybe an infinite question mark. It could be an infinite question mark. And it could be that we just have sort of bubbles and walls and voids that go on forever. But it could also be that once you get a sense of those bubbles and voids that you see a larger pattern. And that could tell you something about the early universe and this quantum foam that generated all this structure.
Starting point is 00:49:12 Or it could be that at that level it's mostly random. We just don't know the answer. Like that's a pretty big question to not know the answer. And maybe once we figure out our address, we can finally get those deliveries from the Amazon aliens. That's right. And I want them in 30 minutes by drone from across the universe. Same century delivery. I'll pay extra for that. All right. Well, we hope you enjoyed that. And you got a little bit of a better sense of where we are in the universe and what's out there for us to discover.
Starting point is 00:49:43 Thanks for listening. See you next time. Thanks for listening and remember that Daniel and Jorge Explain the Universe is a production of IHeartRadio. For more podcasts from IHeartRadio, visit the IHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows. Hi, it's Honey German, and I'm back with season two of my podcast. Grasias, come again. We got you when it comes to the latest in music and entertainment with interviews with some of your favorite Latin artists and celebrities. You didn't have to audition?
Starting point is 00:50:34 No, I didn't audition. I haven't audition in, like, over 25 years. Oh, wow. That's a real G-talk right there. Oh, yeah. We'll talk about all that's viral and trending, with a little bit of cheesement and a whole lot of laughs. And, of course, the great bevras you've come to experience.
Starting point is 00:50:49 Listen to the new season of Dresses Come Again on the I-HeartRadio app, Apple Podcasts, or wherever you get your podcast. Do we really need another podcast with a condescending finance brof trying to tell us how to spend our own money? No thank you. Instead, check out Brown Ambition. Each week, I, your host, Mandy Money, gives you real talk, real advice with a heavy dose of I feel uses. Like on Fridays when I take your questions for the BAQA. Whether you're trying to invest for your future, navigate a toxic workplace, I got you. Listen to Brown Ambition on the IHeart Radio app, Apple Podcast, or wherever you get your podcast.
Starting point is 00:51:29 I'm Dr. Scott Barry Kaufman, host of the psychology podcast. Here's a clip from an upcoming conversation about how to be a better you. When you think about emotion regulation, you're not going to choose an adaptive strategy which is more effortful to use unless you think there's a good outcome. avoidance is easier ignoring is easier denials easier complex problem solving takes effort listen to the psychology podcast on the iHeart radio app apple podcasts or wherever you get your podcasts this is an iHeart podcast

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