Daniel and Kelly’s Extraordinary Universe - Will our supercluster be torn apart?

Episode Date: May 16, 2023

Daniel and Jorge talk about the deep future fate of our cosmic neighborhood.See omnystudio.com/listener for privacy information.

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Hey, Jorge, I have a physics version of Would You Rather? Uh-oh. I'd rather not play? Not an option today. So, would you rather be blown up in a supernova or crushed in a black hole? Well, if I fell into a black hole, there would be time dilation, so it sounds like it would take forever. So maybe I'll go with a supernova, nice and quick. All right. Next one. Would you rather be... eaten by aliens or live your life never knowing if aliens exist. I would pick live my life over being eaten by anything, aliens or otherwise.

Wrong answer, wrong answer. Next one. Would you rather keep playing this game or start the podcast? I'll pick the supernova again, please. I'm crushed. Just trying to blow this up. Hi, I'm Horammy cartoonist and the creator of PhD comics. Hi, I'm Daniel.

I'm a particle physicist and a professor at UC Irvine, and I would rather be eaten by aliens than never know if they exist. For real? Well, I guess if you get to choose when you get eaten by aliens. You know, if you can choose to get it done right before you're going to die of natural causes, maybe that's okay but like right now you would make that choice right now I think this game is all about those loopholes like when people are planning for end of life like do you want to get buried or do you want to get cremated I'm going to fill out a box

that says I want to get eaten by aliens but yeah it'd be nice if they waited till after I already died of natural causes then you know hey barbecue me for the alien potluck that's fine you got to be careful though do you mean like extraterrestrial aliens or people who are you know alien alien to your life or to your city you know what i'm not going to be around so i guess it doesn't really matter oh you're going to be around as you're getting in as long as i get to learn about the aliens while i'm still alive nothing else really matters oh boy anyways welcome to our podcast daniel and horace explain the universe a production of iHeard radio in which we take great pains and great sacrifices to try to

explain the nature of the universe to you we cast our minds out into that dark cosmic make a mystery and wonder what's out there who's out there what's going on out there how big is it is it still sloshing around and what will be its final fate we want to understand the cosmic context of our very existence because it drives the choices we make every day about whether or not we sign ourselves up to be part of an alien barbecue that's right it is a humongous universe full of amazing and awesome things out there that may kill you or eat you and or inspire you to learn more about the universe and the cosmos and how everything works in it. And it's part of this sort of incredible mental history, the trajectory of our sort of

mental map of the cosmos. You know, it started out pretty small, your little village, your neighborhood, eventually expanded to be a larger and larger region. Finally, people started incorporating the cosmos into it, this mental picture of the whole universe that we were in. But it just gets bigger and bigger as we understand where our solar system sits and where our galaxy sits and as our telescopes get more and more powerful, we can now understand even further the context of our cosmic neighborhood. Yeah, it used to be that our context was pretty much like the Earth and people thought that the sun and the moon and the stars all revolved around the Earth.

People thought that the entire universe was just us. Yeah, I was reading about ancient Chinese astronomy and they even calculated like how far away the stars were. They thought it was something like 27,000 miles above the Earth. Oh, that's pretty close. And the Greeks thought that everything moved in like literal crystal spheres around the Earth. That was the original ether. Interesting.

Now, Daniel, do we know for sure that's not true? Do you know for sure that's not true? I mean, we've sent probes out there to visit these things. So we're pretty sure there are no crystal spheres out there moving the planets. By we mean the proverbial we, but have you gone up there and touched these that made sure there's no crystal spheres? I'm going to take NASA's word for it, you know, for sure. I'm not part of the conspiracy community that thinks NASA's been lying to us all these years. You're not part of the Crystal Sphere conspiracy.

I'm sure there's a group of crystal truthists out there. You know, part of the China was right theory? No, but the Chinese did make a lot of really amazing observations. You know, we have like records of eclipses dating back thousands of years from China. And observations are like supernova from almost. a thousand years ago. So it's a really rich history of astronomical observations, some of which are still relevant to our studies today is incredible. Oh, that's pretty cool. Yeah, because as you were saying, our understanding of where and how we fit in this universe keeps growing and growing. And it

seems like each time we just get more and more insignificant with each step. But we become more and more aware of that significance, which makes us sort of like philosophically more important, right? We're like incorporating more of the universe into our minds. No, that makes no sense. We're insignificant specs in this giant universe. But it's better to know about your insignificance because then you've gained some philosophical stature. Like being eaten by aliens doesn't help the fact that you're being eaten by aliens. Still makes it worth it. Still makes it worth it. In fact, that makes it worse. But it does seem like we are getting smaller and smaller in these humorers. And literally, that's true, right? Because every year, every second of the day, the universe or our understanding

of how big it is keeps getting bigger, right? It does. And even though we cannot explore the far-flung edges of the observable universe, we can build this mental model, this sort of map of our neighborhood that tells us where we are in this glittering cosmos. And so even though no human will probably visit those planets or visit those stars, we can still tell you something about what's going on out there. And to me, that's incredible. Yes, we are probably trapped on this rock or our neighboring rocks, but still we can build this map of the cosmos. We can understand something about it. And to me, that's a great achievement, sort of intellectually and scientifically, and what I'm

pretty proud of. Yeah. Again, I think you're using the proverbial we there. You're proud of the work of others. Let's be honest here. No, I'm standing on the shoulders of many, many giants. And I'm proud of their work. Absolutely.

I'm not personally taking credit for our understanding of the universe in case anybody misunderstood. But at least we're helping, I guess, talk about what they've done and disseminate this information out to others. And it's interesting what you said, like, that we might never reach those places that we're seeing far, far away. I'm wondering if that's really true. I guess that's true because our view of the universe is expanding at the speed of light, and there's no way that humans could outpace that, right? Yeah, it's amazing. We can see things that are moving away from us faster than the speed of light. A bunch of listeners wrote in and asked, like, how does that work? We have a whole episode covering it. But,

Briefly, the thing to understand when you're looking at an object and they tell you, oh, this thing is 30 billion light years away and it's moving away from us faster than the speed of light is that you're not seeing it where it is now. They're telling you where it is now, but you're seeing the light that was emitted from it when it was much, much closer. So it used to be much closer and it's sent a photon our way. In the meantime, it's moved really, really far away. When they say here, we're looking at a galaxy that's really, really far away. We're not seeing light that came to us from it when it was that far away. we're seeing light that came to us when it was much, much closer. Light that leaves it now, we will never see,

which means also we will never visit it. Yeah, because the universe is expanding faster and faster every time, every second of the day. Although we don't know what's going to happen in the future, right? It could be that in the far distant future or maybe tomorrow the universe might decide, hey, I think I'm going to stop growing and I'm going to collapse back on myself, and in which case we're going to basically visit every place in the universe at some point. Yeah, or they're going to come visit us. they're going to bring with them all their aliens with all their barbecue tools.

All their appetites. Well, maybe the big joke is that in the end, the universe eats us all. Well, we are the universe. So I guess the universe eats itself. I'm not sure how that works. Whoa, dude. And even though we are learning that we are a tiny speck in a vast, vast cosmos, I think it does make us sort of like philosophically or intellectually more powerful to have grappled with that vast cosmos.

It's better at least than being ignorant of what's going on. Right, right. But don't they say ignorance is bliss sometimes? Who's looking for bliss, man? I'm looking for knowledge. Maybe that's the difference between you and me, Daniel. I'll go for bliss any day. Okay. Well, I'm glad we can split the tasks. But it's also fun to think about that far future you were talking about and wondering, like, what does the future hold? Will our solar system survive for a billion years? Will our galaxy survive for 10 billion years? what exactly is going to happen to our cosmic neighborhood over cosmic deep time. Yeah, because as we mentioned, the universe is expanding faster and faster and faster,

and that has some pretty dramatic consequences for some of the bigger structures in the universe. And so today on the podcast, we'll be tackling the question. Will our super cluster be torn apart? Sounds kind of sad. Like a chunk of juicy barbecue. Wow, who would eat a giant super cluster of galaxies? Some giant super space crab, I suppose. Oh, boy.

And how big does the barbecue sauce bottle need to be? Well, this is an interesting question. And so we'll dig into it of what a super cluster is. What does it mean for it to be torn apart? And what could be causing it to be torn apart? But as usual, we were wondering how many people had considered these words together as a question out there in the internet. So thanks very much to everybody who participates in this. segment of our podcast. It's super fun for us to hear what you're thinking about the topic of the day.

Please don't be shy if you'd like to participate in the future. Just write to me to questions at danielanhorpe.com. So think about it for a second. Do you think our super cluster will be torn apart? Here's what people have to say. I say no. I believe that dark matter and dark energy will keep it together just like it build the super cluster that we see today. Well, Our supercluster, if I believe right, is a collection of galaxies that we're in, kind of grouped up. So if anything, I feel like it would get larger just by gravitationally attracting other galaxies that are just floating out there. If I get it right, the galaxies of our supercluster won't drift apart due to the expansion of the universe, but they might dive into each other. A supercluster is a group of galaxies.

dark energy obviously is moving things apart but I think that a galaxy would stay together but that galaxies would separate from each other so I reckon our supercluster will be torn apart all right some people are feeling optimistic about our super cluster it looks like three to one for our super clusters sticking together we got some optimists out there yeah yeah everyone wants to remain I guess in a cluster They want to stay cozy. No one wants to blow up our spot. Yeah, but I guess some people mention gravity as keeping us together

instead of letting the supercluster get torn apart. And some people mention dark matter as a way to keep things together. Yeah, and the overall theme here is pretty much spot on that the universe is in a tug of war between gravity and dark energy. And those things play out very differently on different distances and different scales. And so the fascinating question is like at what point does dark energy win? and where will gravity win?

Who will eat who? Gravity versus dark energy. That's like Godzilla versus King Kong. That's like slow roasted ribs versus grilled chicken. I'll just eat them both, man. Because no those dos. Sounds good. Well, let's dive into this tasty topic here.

Step us through, Daniel. What is a super cluster of galaxies? So a super cluster is the biggest thing in the universe. universe. It's the largest structure we think can exist in the universe. And this episode is going to hinge closely on what we mean by a structure. What is a thing in the universe? Because you could just look out in space and say, I'm going to group all this stuff together and call it a thing and give it a name, the way we sort of do for constellations. But astronomers like to think about things in the universe structures as things that sort of hold themselves together, that have enough gravity

to be tied together, to be an equilibrium. So in our immediate neighborhood, for example, we think of the solar system as a thing. The Earth is going around the sun, and it's going to keep doing that. Gravity is holding the Earth around the sun and all the other planets. So we think of the solar system as a structure,

as this gravitationally bound kind of object. Yeah, because I guess if you think about just the word structure and what it means in our everyday lives, it basically just means like things that are clumped together, right? Or that move together or that can be separate. separated from each other and you sort of drill down into it like even the house you're sitting on or the building you're sitting on or maybe even the car you're sitting on is just a collection of loose particles being held together by a force in the universe like they're not part of the same thing they're individual particles but there's just some force that keeps them all moving together yeah and it feels like a really natural thing right to say I'm held together I'm a thing you're held together you're another thing even if we're standing next to each other it's easy to draw the line between us and say like we're I end and you begin, that's sort of philosophically very straightforward. And so we imagine maybe that's possible to do for other stuff too, right, to say, well,

here's one planet and there's another planet to draw these lines and say, this thing holds itself together and that thing holds itself together. So that's sort of the idea of a structure. But it can also get kind of fuzzy. Like when you look up in the sky and you see a cloud, it's this big blob of vapor. It's not really holding itself together. I mean, it looks like a thing, sort of localized and clumped, but it's definitely not gravitationally holding itself together.

It just sort of happens to be all in the same place at the same time or like a crowd in a park at lunchtime, right? They all happen to be near each other. They're clumped, but they're not holding themselves together. So there can be sometimes things that are like near each other. There are clumps, but not structures. Interesting. Yeah. A crowd is a good example, right?

Because it may look like a cluster or like a from afar might look like a clump of things. But really, there's nothing keeping those individual people or structures together, right? They could at any moment just leave the group. Yeah, every kindergarten teacher knows that when you try to take them out on a field trip, right? They can all just suddenly run in any random direction. Yeah, whereas maybe like for the planet Earth, all the rocks on planet Earth are being kept from flying away by gravity, by a force. And it's really fascinating to think about the sort of levels of structure, right? Like a rock is a structure, but it's also part of a larger structure, the Earth.

And the Earth, of course, is a structure. But again, it's part of a larger structure. So we have this incredible nested hierarchy of structures, which is really fascinating to think about like the scale of those things, right? Like an atom is a structure. You're made of so many structures and so many levels. It's incredible to think about like how organized the universe is. And there's a whole group of philosophers who study this kind of thing and wonder like, why do we have structure these distances and not other distances and does it bubble up from the fundamental laws of the universe and all sorts of fascinating philosophical rabbit holes. But it's also just kind of fun to figure out, like, what is the structure?

What is our cosmic neighborhood? And so we can, like, zoom out step by step and understand how we fit in to this sort of larger cosmic set of, like, Russian nesting dolls. Yeah, because I guess, you know, sort of like you were saying, the atoms in my body make up my structure, but they're all also kind of being pulled by the gravity of the Earth, right? So, like, is it more part of my structure or are all the atoms in my body more part of the Earth's structure. And even like the atoms in my body are being pulled by the gravity of the sun,

but we wouldn't say like, hey, I'm just, me and the sun are one. Even though if you sort of follow the chain of forces, that we are sort of in the same structure as the sun. Yeah. And so you're part of many structures, or you could say that there's substructure, right? You could just look at the whole galaxy and say the galaxy is a blob, but obviously it has substructure. It's not just a smooth distribution of atoms.

There are stars in solar systems and even clumps to those. They're like these groups of stars are all formed together that are still moving together like that kindergarten group. So there's sort of lots of layers of structure. And it's fascinating to ask like how many layers are there? How many layers can we zoom out and still see things that seem to be holding themselves together? So we start with ourselves. And then of course we have the Earth and then there's the solar system and then we zoom out. The next sort of big layer of structure would either be like a group of star and

that we all form together with, or you would zoom all the way out to the galaxy. Because those groups of stars that form together, they don't really hold themselves together for very long. They tend to disperse into the galaxy. Do we know that for sure? Or, I mean, like, do we know which stars are near us? And would you say maybe they're too far away for their gravity to really affect us? Yeah, other stars are too far away for the gravity to really affect us. And we all have velocity through the galaxy. And so we know a lot about actually how stars dissipate from their original clusters.

it can take tens or hundreds of millions of years, but we definitely see evidence of that. When we look out at the pattern of the stars in our galaxy, it also helps us understand like how the stars are moving. For example, like the Big Dipper is a group of stars that are all formed together and they're moving together, but they're also moving really fast and they're kind of close by, which means that the big Dipper is changing. You don't think about the constellations as changing very much, but they actually are all moving. We're not all moving at the same relative velocity.

So like the galaxy is a big dipper. sloshing bathtub of stars. So the big dipper changes. And over like 100,000 years or a few hundred thousand years, the big dipper will no longer look like the big dipper. Now, are they, would you say they're a structure or are they just moving together like a crowd or like a wisp of cloud? They are not a structure because they're not going to hold themselves together. They're not like tight enough to be a structure. They're definitely going to dissolve into the larger sort of bathtub of the galaxy. There are sometimes some structures to the galaxy, but those tend to be like little dwarf galaxies that orbit the Milky Way and that have their own gravitational hold on

themselves that haven't gotten pulled apart by the Milky Way. But within the Milky Way, there aren't really those kinds of structures. So you would say like after our solar system, the next structure is a galaxy. You wouldn't maybe call the arms of a galaxy a structure? Well, those are density waves, right? Even the arms of the galaxy are not physical structures. It's not like the same stars are moving through those arms. The arms are a wave through the stars. Like when you go to a football game and people do the wave, that wave itself is not a structure. It's just an arrangement of the people as they move up and down. Galaxy arms are the same way. They're not physical structures. They're just density waves. So they're not actually holding themselves together. Just like waves in the ocean

are not really structures. They're not bound together. And so our solar system, our star, is not part of a, like a mini dwarf galaxy. We're just out in the larger Milky Way galaxy. Yeah, we're just floating in the bathtub of the Milky Way along with hundreds of billions of other stars. And potentially aliens that might eat us. One of us, right? Sounds like a dangerous hot tub. Well, let's dig into the next level of structure in the universe and let's see how big we can go. How far can we add or recognize structure in the universe and what's going to happen to all that structure at the end of time. So let's dig into that.

But first, let's take a quick break. December 29th, 1975, LaGuardia Airport. 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. In its wake, a new kind of enemy emerged, and it was here 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. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Oh, 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 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 O'Coh. Storytime Podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. In sitcoms, when someone has a problem, they just blurt it out and move on. Well, I lost my job and my parakeet is missing. How is your day? But the real world is different. Managing life's challenges can be overwhelming. So, what do we do? We get support. The Huntsman Mental Health Institute and the Ad Council

have mental health resources available for you at loveyourmindtay.org. That's loveyourmindtay.org. See how much further you can go when you take care of your mental health. Have you ever wished for a change but weren't sure how to make it? Maybe you felt stuck in a job, a place, or even a relationship. I'm Emily Tish Sussman, and on she pivots, I dive into the inspiring pivots of women who have taken big leaps in their lives and careers. I'm Gretchen Whitmer, Jody Sweeten. Monica Patton. Elaine Welter-A.

I'm Jessica Voss. And that's when I was like, I got to go. I don't know how, but that kicked off the pivot of how to make. the transition. Learn how to get comfortable pivoting because your life is going to be full of them. Every episode gets real about the why behind these changes and gives you the inspiration and maybe the push to make your next pivot. Listen to these women and more on ShePivots now on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. asking the question, will our super cluster be torn apart, which kind of sounds like an oxymoron

question or contradictory question? Will something that's clustered together and not be clustered together? Yeah. In the end, we're going to learn that astronomers are arguing about how to define a super cluster. And some definitions make the answer obvious and some definitions make the answer to this question very fuzzy. But we were talking about how, you know, things, how do you define structures and it seems like sometimes like in a cloud or in a crowd things might look like they're together but really they can fall apart at any point so you wouldn't call that a structure but like the atoms in your body or the atoms in the building or car you're sitting on they're held together pretty tightly by forces and they basically sort of ignore other forces in favor of the forces that are

holding them together and so maybe that's why we call them a structure that's right and it can be gravitational or it can be electromagnetic or can be the strong force that forms these structures Like the proton is a structure of the strong force and the atom is a structure of electromagnetism, but at larger distances, basically anything bigger than a few meters, it's mostly gravity that takes over because the other forces are so powerful that they tend to neutralize themselves. Anything that has a large positive or negative charge is going to attract the opposite charge and end up neutralizing itself. But over the large distances, it's gravity that forms structure because gravity cannot be neutralized.

Essentially, it's only attractive. there are a few scenarios we can talk about with like repulsive gravity and dark energy might be an example of that but on the whole gravity is attractive and so it's the force that's responsible for most of the structure we think about in the universe yeah like after about the size of a planet there's no other forces really at play in the universe that we know of maybe there's something hitting out there could dark matter be some kind of new force it could and dark energy is definitely in that category we don't know if it's a manifestation of gravity due to like the quantum energy of space or something totally else and weird. All right. Well, we talked about how we're part of a solar system and the solar system is part of a bigger structure called the Milky Way galaxy. What's after that? So the galaxies aren't just like floating out in space sprinkled evenly through the universe.

They tend to clump together. And they can clump together into something that we call a galactic group or a group of galaxies. In our galaxy, the Milky Way, is part of a group we call the local group, very cleverly. And it has about 50-ish galaxies in it. The biggest one is Andromeda, which is also the nearest one to us. And so these are galaxies that are not just near us out of convenience. We're actually sort of locked together with them in some sort of gravitational dance, right? Yeah, we think that these galaxies are holding themselves together.

They're like a single gravitational object. They are orbiting the center of mass of all of these galaxies. And people hear a lot that the universe is expanding and everything is. getting farther and farther away. And that's true sort of on the whole when you look at vast distances. But nearby, gravity is powerful enough to hold us together. And that's happening also with these galaxies. That's why, for example, we are headed towards the Andromeda Galaxy. And in a few billion years, our galaxy and Indromeda will collide and will merge because gravity is winning the battle over the expansion of space. So this local group, we think, is a thing. It's a structure that

gravity is powerful enough to hold together. And now what kind of shape does this local group have? Is it like a disk, like our solar system or the galaxy? Or is it still kind of like a fuzzy cloud of things moving in all directions? It doesn't really have a great shape because it's sort of weirdly distributed. Like there's Andromeda. Then there's the Milky Way. There's another galaxy called the Triangulum Galaxy.

And the rest of it is like a sprinkle of little tiny galaxies. So they're not like nicely organized into a flat disk or anything like that. It's just sort of like a blob. Or at least not yet, right? Maybe if you fast forward a few billion years, things will even out into a disk because that's what things do in space. They organize themselves into disks, right? They do tend to do that if you give them enough time because they're spinning and gravity will collapse everything down eventually, except along the plane of their spin, they can resist gravity a little bit, which is why they end up as disks. So in sort of one direction they can collapse and along the other two dimensions on that plane, they end up sort of spinning around, which is how you get a flat solar system and a flat galaxy.

eventually though we think that gravity will win that those things will bump against each other and lose angular momentum or they will radiate gravitational waves and lose that energy and eventually we think that gravitationally bound objects will all collapse together first into one big galaxy

and then eventually just into one big black hole yikes but before that happens we can see other kinds of structures right bigger structure so like a group of galaxies can be part of a larger kind of thing yeah so we call this either a group or a cluster of galaxies, and depending on the size, like if there aren't that many galaxies in it,

like in ours, we call it a group. If there are more galaxies in it, you can call it a cluster. And so nearby, for example, is the Virgo cluster. It has more than a thousand galaxies that are like the Milky Way. So it's much, much bigger than the local group. And we think it is also like an object that has structure.

We think it's going to hold itself together, that there's enough gravity to keep itself together. Yeah, isn't it pretty amazing to think, Even at these numbers like a thousand, a thousand doesn't sound like a lot. But if you imagine a thousand galaxies like the Milky Way, that is sort of mind blowing, right? Like we think our galaxy is pretty huge and we'll probably never get to the other side of it and has billions of stars. Now imagine there are thousands of these things out there in space. And the thing that blows my mind is the planets, right?

Even in our galaxy, we know there are hundreds of billions of stars and a significant fraction of those have Earth-like planets. You know, planets about the same size. with about the same surface temperature. We don't really know that much more about them. But like, that's a lot of Earth-like planets. We're talking about tens of billions just in our galaxy. And now multiply that by a thousand for all the galaxies in the Virgo cluster. It's hard to keep track of, like, all the places aliens could be sharpening their barbecue tools.

Yeah, so let's not think about that. Yeah, I agree with you. But the Virgo cluster is like the biggest thing around. There are other little galaxy groups nearby, like there's the M81 group and the sculptor group, other little groups of galaxies that are sort of in this sort of the same size as our group. But the Virgo cluster is like the big Papa and Mama galaxy cluster nearby. It's like the most massive thing in the nearby universe. Well, it's interesting with gravity, I feel, because gravity doesn't have a limit, right? Like there's no distance limit for gravity.

Like this Virgo cluster is super duper, duper far away from us. but technically speaking, like the atoms in my body and in your body and everybody's bodies is being tugged, pulled by the gravity of that cluster super far away. That's right. Everything in the universe technically is pulling on you gravitationally. Gravity does have this weakness, though, which is that its power drops as the distance squared. So if you're twice as far away from something, it's gravity goes down by a factor of four. If you're 10 times further away, then the gravity goes down by a factor of 100.

And this gets to be a very powerful obstacle to gravity as distances grow large. And so the Virgo cluster, even though it's the most massive thing in the nearby universe, it's like 50 or 60 million light years away. That's a big distance to square, right? So its gravity is really tiny, which is why it's not obvious whether our little group, the local group and the Virgo cluster should be considered as part of some larger object. Right. It gets attenuated a lot.

It weakened a lot by distance. But it's still there, right? Like I feel like I'm sensing, I have this feeling of like a small tendril of force that pulls me from the atoms in my body to the Virgo cluster, right? And it also kind of depends. Like what if the Virgo cluster was super duper massive, right? We would eventually feel their gravity. Yeah, that's true. And we do feel it's gravity.

You're absolutely right. I feel like you're just sort of preparing an argument for when the aliens come and you're like, hey, man, we're all part of the same thing. We can feel your gravity. And we do, and we can feel that gravity. And there's another way in which we are connected to those objects. Right now, we're just thinking mostly about the stars, the things that shine brightly. But there are these filaments that connect us to the other galaxies. Like between us and Andromeda is not empty space.

There's this filament, this like string of both matter, like hydrogen atoms, et cetera, and also dark matter. So it's not like a bunch of dots out in space, these galaxies. They're connected to each other. It's part of some huge cosmic web where the other parts are more invisible because they're not glowing. Yeah, it's sort of like a spider's web, right? Like if you look at a picture of the universe and all the stars in it, the stars, even though they're pinpointed, they sort of don't look like a random white noise. They sort of look like a spider's web kind of.

And in between those dots, there really is stuff. You know, galaxies form in certain locations because that happens to be where there was a little bit more dark matter. So there's like a blob of dark matter there that's gathered together enough light to start fusion going in those stars. But between them, there are these filaments of gas and dark matter still flowing into those halos. So you could think about it like a network of lakes with rivers flowing into them, still filling them up. So galaxies are still gathering dark matter and gas from these filaments. Structure there is still sort of forming. Even though 14 billion years have gone by, things are still happening out there.

in the universe. I guess if there's a big cloud of something like hydrogen out there in the middle of empty space, gravity would be pulling it together, that cloud together into a smaller cloud, and then our gravity would be, and the gravity of other clusters would be trying to suck that gas towards them. And so that's why maybe you get these tendrils, these sort of like tentacles of gas out there in space because they're being stretched down and sucked into the different galaxies.

Exactly. And mostly it's the dark matter doing that. Remember, we only see the visible matter, but that's 20, percent of the matter that's out there, most of the gravity in the universe, most of those tendrils you feel from the other cluster are actually from the dark matter in that cluster, because that's most of the matter. And so most of the gravity in the universe, like the reason we have a galaxy here and not somewhere else is because there was dark matter to form this structure. It created this like gravitational well, the sort of lake to pull all the other rivers of matter

into it. Cool. Well, after a cluster of galaxies, what's next? So what's next? is a little bit controversial, and in the last 10 years or so, there's been a lot of arguments about it, but there's a group of astronomers out there that say that all these clusters and these little groups can be gathered together into something bigger, called a supercluster. The super cluster would take like the Virgo cluster and our little group and a bunch of other things, including like the great attractor and the Norma cluster and the Centaurus cluster and many others into some huge object that has like a hundred thousand galaxies in it. Right. And this supercluster is called the Lanikea supercluster, right?

Yeah, it's a Hawaiian word that means immense heaven. And it was defined in like 2014 when a bunch of astronomers looked at the velocity of all these things and said, hmm, you know what? All these things are sort of like falling towards themselves. And there's another blob of stuff over there that's falling towards themselves. And so they figure out how to sort of like draw a line between one set of blobs and another set of blobs.

And they said, we're in this blob over here. I see. But can you make the mathematical calculation? Like if you compute the gravity that we're feeling between these clusters and does it really work out that you can group these super clusters as one? Or is it more like an illusion like a wisp of cloud or a crowd or a crowd of people in a park? Yeah, that's exactly the question. And that's really what we're answering today is what is the future of this supercluster? Is it going to hold itself together or is it going to get torn apart? because we've been talking about gravity so far, but there's another force at play here and that's dark energy. If there was only gravity, then this thing would collapse.

Lanakaea would definitely fall into one big object and maybe form one super galaxy and one super black hole. There is enough gravity if the universe wasn't expanding to pull this thing together. It's already right now falling inwards. Everything in the Lanakaa super cluster has an overall in falling velocity.

But there's another player on this stage. right, which is the expansion of the universe. And this has a very different behavior as distances grow large. Like gravity gets weaker and weaker as distances grow large, but dark energy, this accelerating expansion of the universe, gets more powerful as distances grow large. So at some point, it takes over. There's like a crossover point where dark energy starts to win.

Well, let's dig into that because that is the main question of the episode. Now, we are in the Lankea's supercluster. And so the question is, is something tearing it apart? It's the biggest structure in the universe. And so, Danny, you're saying that maybe dark energy is tearing it apart or maybe at least fraying it at the edges? Yeah, dark energy is definitely working to tear it apart. And listeners write in all the time and ask about dark energy and have this idea sometimes

that dark energy is something happening at the edges of the universe, that there's something pulling on us from the outside or that maybe the expansion is only happening out there between galaxies. But the expansion is happening everywhere. Every chunk of space is expanding. Like the Hubble constant is a measure of how fast things are expanding, and it's like 70 kilometers per second per megaparsec, which is sort of a hard thing to get your mind around. But really, it just means that like every megaparsec, which is like three light years, grows by about 70 kilometers every second. And that happens everywhere in space.

If you have a smaller distance, like the distance between the Earth and the Sun, which is only a few tens of millions of miles, it would grow by. much smaller amount than 70 kilometers every second. So that expansion is happening everywhere, but it's sort of faint and weak. It's not very strong over short distances. And gravity is strong enough to hold us together against this like very weak breeze of dark energy. But then large distances when gravity is weak, dark energy is more powerful. It sort of adds up as you get to these bigger distances. And so for the super cluster, it really is an interesting question of whether that's the crossover point.

Yeah, it's interesting to think about like even here in the room where I'm at and the room where you are and where our listeners are, if you just stare at your hand, like the space that your hand is occupying is expanding. It's getting, trying to like pull your hand apart in a way, except that your hand is being held together by the bonds of the atoms in it. But if it wasn't, your hand would just kind of dissipate eventually, right? Yeah, exactly. If there wasn't gravity and there weren't those forces, then dark energy would pull your hand apart. and it would pull the earth from the sun. So there's a bunch of really interesting things all happening at the same time, like gravity needs time to form structure.

You start from like a fuzzy universe and it gradually pulls things together. And so as time goes on, gravity makes bigger and bigger and bigger structures. So one reason we don't have bigger structures than superclusters or even if superclusters count a structure is just time. Like without dark energy, if you ran the universe forward, it would form larger and larger and larger structures. But dark energy turned on a few billion years ago and it started accelerating the expansion of the universe. So gravity is sort of running out of time, which means something kind of fascinating. It means that we are living maybe at the moment of the largest structures in the

universe. Well, I think that's kind of the point of discussion. Is dark energy eventually going to tear our super cluster apart or is maybe that expansion not strong enough to really tear apart and keep things the way they are forever? Right. That's kind of the question. we're asking today. Yeah, that's right. But whether or not our super cluster survives, there will never be anything bigger in the universe because dark energy is getting more and more powerful. And so gravity will never have time to make anything bigger.

Like if a structure hasn't formed by now in the universe, it will not because dark energy is just growing in power. So whether or not our super cluster survives, nothing bigger than anything that's been made already will ever be made. Well, let's dig into that and what it might mean for our local structure or superstructure of galaxies. Does that reduce our chances of getting eaten by aliens? We'll see. First, let's take another quick break.

December 29th, 1975, LaGuardia Airport. 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.

In its wake, a new kind of enemy emerged, and it was here 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. My boyfriend's professor is way too friendly, and now I'm seriously suspicious.

Wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on the okay story time 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 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. Have you ever wished for a change but weren't sure how to make it? Maybe you felt stuck in a job, a place, or even a relationship. I'm Emily Tish Sussman, and on she pivots, I dive into the inspiring pivots of women who have taken big leaps in their lives and careers. I'm Gretchen Whitmer, Jody Sweeten. Monica Patton.

Elaine Welterah. I'm Jessica Voss. And that's when I was like, I got to go. I don't know how, but that kicked off the pivot of how to make the transition. Learn how to get comfortable pivoting because your life is going to be full of them. Every episode gets real about the why behind these changes and gives you the inspiration and maybe the push to make your next pivot. Listen to these women and more on She Pivots, now on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. In sitcoms, when someone has a problem, they,

just blurt it out and move on. Well, I lost my job and my parakeet is missing. How is your day? But the real world is different. Managing life's challenges can be overwhelming. So, what do we do? We get support. The Huntsman Mental Health Institute and the Ad Council have mental health resources available for you at loveyourmindtay.org.

That's loveyourmindtay.org. See how much further you can go when you take care of your mental health. All right, we're talking about getting eaten by aliens. Now, Daniel, are you sort of preparing, it sounds like you look forward to it. Now, are you preparing yourself? Are you staying in shape or are you trying to fatten yourself up like a goose so that you're tastier to the aliens? You know, are you trying to pack on those calories?

I just don't even know. Like, what do aliens like? How am I supposed to anticipate what they're going to find yummy? Like, so I'm just living my life, you know, and hoping that they pick me. I'm hoping they pick you, too, over me. Hey, something we can agree on. Awesome. Well, we're talking about whether, we're actually talking about whether our super cluster, which is called Lankea, which is a cluster of galaxy clusters, will one day be torn apart

because of dark energy. Now, dark energy is expanding all space as far as we know. and the question is, is it expanding space faster than Lanikea can hold itself together? And it sounds like you have the answer to that. I do, yeah. So originally they defined a supercluster to be this object because everything was sort of falling in towards itself. They like delineated a blob of stuff that was moving towards itself and the next supercluster

is a blob that's moving towards itself. But then astronomers thought, hmm, that's not really enough. Like what we want is something that's going to survive. We want to define a super cluster to be something that's going to be something that. is going to manage to hold itself together against dark energy. So they did a bunch of calculations, and it looks like it's probably not going to make it. It looks like the super cluster is very loosely organized. It's just more like a cloud or like a crowd.

You know, it happens to be nearby, but it's not really like in equilibrium. You know, like the Earth and the Sun had a lot of time to sort of get in balance and find a place where they're happy together and the Earth can orbit forever and be here. But the super cluster, like we said earlier, hasn't really had a lot of. lot of time to gather together and to form something solid. It's just sort of like a big blob of stuff that happen to be near each other and are starting to fall in a little bit. But dark energy is powerful enough that they're pretty sure it's going to tear it apart. Now, you mentioned one of the reasons is that dark energy is getting stronger. Now, is it getting stronger at the local

level? Or is it just, are you saying it's getting stronger because the universe is getting bigger and so therefore there's more dark energy? Is it getting stronger measurably? Like inside of my hand is this dark energy that I would feel over the course of my life getting stronger or is it going to be constant dark energy is everywhere at the same level so it's a constant in space here and there and in other galaxies every chunk of space has the same amount of dark energy so when the universe expands it's making more space which means more dark energy doesn't get diluted it's a constant in space that's not true for other stuff like matter or radiation. As the universe expands, matter gets more dilute because more space doesn't mean more

matter. So as time goes on, the expansion of the universe means dark energy is constant, but then it's an increasing fraction of the energy of the universe because it doesn't get diluted and other stuff does. And when dark energy is an increasing fraction, that triggers more expansion, which only tells the balance further towards dark energy. So it's like a runaway effect. Once dark energy, starts to win, which happened about six billion years ago, it will zoom ahead and be impossible to catch up to. But about seeing it change, we live such short lives that we can't really notice it changing on our time scales. But we can look back into the past by looking out into deep space and seeing how things used to be. And of course, there's a huge asterisk to all of this

because we don't really understand dark energy and what's going on and what's making this happen. And so the rules could be very different from this very simple model that honestly, we're pretty sure is wrong. Right. Well, I guess what I mean is that, you know, we've always talked about dark energy as being kind of the force that's expanding the universe, it's expanding space. And I always think of it as sort of like the foot in the accelerator. So like when I'm driving, I press the accelerator and I usually leave it at a certain level to keep going at a certain speed. And if I want to accelerate, go faster, I'd press it harder. And if I want to go slower, I let go of the pedal. Now, it sort of seems from what I've, we've talked about before,

that is that, you know, the pedal of dark energy is sort of pretty constant. And for example, our solar system is never going to be torn apart by dark energy because the gravitational bonds between us and the sun is strong enough that even if the space between us gets bigger and bigger and bigger, we're always going to hang on to the sun. Dark energy is expanding the space in our solar system, but it doesn't have much effect over those short distances. And short distances is when gravity is the most powerful. So gravity is always going to be powerful enough to hold the solar system together.

If dark energy is a constant in space. Remember, a constant in space can still be an increasing fraction of the universe's energy budget, which leads to accelerating expansion, even if the dark energy in any given chunk of space isn't changing. Except for the scenario of the big rip where dark energy gets more powerful

and even tears our solar system apart and even our atoms. But you're right, in our current projection of dark energy, it will not tear apart our solar system. Right. And so it's because it's not being accelerated enough. Now, at the level of a galaxy, do we currently think that our galaxy is going to be torn apart or not?

We think our galaxy is going to survive, and we think our group is going to survive. So everything below a super cluster, we're pretty sure gravity is already won and it's going to continue to win. Again, assuming this naive projection of dark energy, continuing at the same rate that it's been continuing, that it's not going to ramp up into the big rip or turn around into the big crunch. So our solar system will survive, our galaxy will survive,

our local group will survive, the Virgo cluster nearby will survive. But the question is, will our supercluster survive. And that's where dark energy starts to win. Dark energy will tear these groups of galaxies apart and basically pull apart Lanakaa. Because the things that make up Lankea, you know, our cluster, the Virgo cluster, the great attractor, they are being attracted to each other, but not more than the expansion of the huge amount of space in between them. That's kind of what you're saying. Yeah, it's just too big, right? Gravity gets weak over those huge distances.

It does not have the strength to overcome dark energy. And as the distances get bigger, dark energy becomes harder and harder to surmount. Like, it doesn't take that much mass and that much gravity to overcome dark energy in our solar system. takes more mass to overcome the dark energy in the galaxy and even more to overcome the dark energy of the group. But to overcome the dark energy of the supercluster, we need an incredible amount of mass because of the vast distances involved. So you're saying that Lanikea, the super cluster of galaxies, it's really more like a visual cluster, right? It's more of a visual structure. It looks like it's sort of holding together. It looks like a wisp of cloud or a crowd of people in

the park. But really, there's nothing that much holding it together. Or at least, proportionally to the dark energy in the universe. Yeah, our supercluster seems to be right about that turnover point where things that are smaller or more massive, either one, would survive. And things that are bigger definitely would not. So it's sort of fascinating. It's like the biggest kind of blob we can identify, but it's not really technically a structure.

So there were some papers a few years ago suggesting we shouldn't be calling Lenikea a supercluster because it's not a structure. And they said maybe we should redefine what a structure is as something that will survive in the future, right? Things that will hold themselves together in the long term after dark energy has played itself out. So by that definition, the Lanakia supercluster is not actually a structure,

and we shouldn't even be calling it a super cluster. Well, I mean, as long as you're playing with definitions, you can go either way, I feel like, right? Like you could just redefine what a super cluster means. A super cluster could just mean like a cloud or a crowd in a park, right? Maybe you can just define a supercluster as not necessarily a structure, but you can still call it a super cluster, right? Because the word cluster just means like, hey, hanging out together. I suppose.

I mean, you could call it a banana if you wanted. Yeah. We wanted these words to have some meaning to them. And so these papers suggest that we shouldn't. And they actually suggest another name because there are some other super clusters that they do think will hold themselves together. So some superclusters are more massive or a little bit closer together. and they think they will overcome dark energy. And they suggest calling these things superstiz clusters.

Super so what? It's a word in Latin that means survivor. Probably not pronouncing it correctly, but I think it's superstiz clusters is the new name for superclusters that will survive dark energy. It sounds like a really rad about way for, what did you say,

what did you call structures, like super structures? Why do we have to go Latin? Well, because not all super clusters are structures. They don't hold themselves together. And you're right, we could just put a name on things, but we like this hierarchy of structures. We like thinking about the universe in terms of the structures all the way down from the proton, zooming out to the biggest structures in the universe. And we want a consistency there. We want it to mean something for there to be a structure.

You don't want just like an arbitrary definition at every level. Well, I feel like maybe you're only having to adjust this definition because of dark energy, right? Like if it wasn't for dark energy, yeah, Lankea would be a structure and it would be gravitational bound and it would last until the end of time. But you have dark energy, which will make it fuzzy up in the future, except that you don't know what dark energy is going to do, right? So it seems a little bit like you're rushing your head to redefine everything based on something you don't know what's going to happen. Well, you know, astronomers love fights over names and definitions and who gets to name something. So this is one of the hot topics these days. But you're right that the definition of depends a little bit on what happens in the future.

In that sense, it's sort of like the way you think about an event horizon for a black hole. Like the event horizon isn't a physical structure. It's just like a delineation that says anything passed here in the infinite future will never escape. To really know that, you have to see the infinite future. We just sort of project it. And in the same way, we like group this stuff together and say, hey, is this going to survive? If so, then we can call it a cluster or a structure or a super cluster or a super cluster. or a superstiz cluster or whatever the astronomers finally settle on.

But the basic story is that if dark energy continues the way it has been, probably Lanakaa will just dissolve into a bunch of islands of mass. It sounds more like you're saying, we shouldn't call anything anything until the end of time. There you go. That's exactly right. We want to be totally accurate about everything. We've got to wait to the end of the universe.

Then we'll know what was going on. Well, let's spend a minute here because we still have like a few minutes left here Talking about the dark energy, right? Because it seems like it all depends on what dark energy is going to do, whether the universe is going to press harder on the accelerator or press lower on the accelerator. What's been the history of that? Like since the beginning of the universe, there was a huge expansion, and then it slowed down and now it's picking back up again, right?

Yeah, that's true. And there's sort of a bunch of different time periods to talk about there. Like there was inflation very, very early on, huge expansion and very short time scales. We don't understand what caused that at all. There's a few theories, the Infliton field, whatever, but it's a big question mark. And then after that, you know, what we call the Big Bang, the sort of like more gradual expansion of the universe as it cools, we have pretty good models of that. We have gravity and we have dark energy.

We have all the other forces that come into play. And in that period, we can model dark energy as constant, saying like a chunk of space has the same amount of potential energy and that creates this repulsive field in general relativity which drives the expansion of the universe. Remember that dark energy can be a constant in space. Every chunk has the same amount, but still be a growing fraction of the universe's energy because other stuff is getting diluted as things expand.

So dark energy is both constant and taking over as other things get more dilute. It's not exactly true because we make these measurements over time. We get slightly different answers. So nobody really knows if that's true if it needs a little bit of adjusting, We had a whole episode about early dark energy, whether dark energy was more powerful early on, this kind of stuff.

But mostly we can explain the history of the universe after that first inflationary period. We can explain it assuming dark energy is constant. So that seems to be a reasonable assumption. Meaning that the universe is not pressing the accelerator faster. It's just kind of leaving it on. That's right. It's pressing the accelerator at the same level, meaning every part of space is the same amount of dark energy.

But eventually that does take over. You know, like when you press the accelerator on your car, there are other things keeping you from going faster and faster, right? There's friction and this air resistance, whatever. That doesn't quite apply to this model because in this model, the level that the accelerator is at ends up speeding us up. It's like winning against the other forces. So it really is accelerating the expansion of the universe. So sort of two different ideas there. One is the amount of dark energy in space is constant, but because it overcomes the other things, it ends up accelerating the expansion of.

of the universe. Meaning that the space is growing at an accelerated rate. But is that acceleration getting faster or is it slowing down or is it pretty constant? We think that acceleration itself is pretty constant, yes. And we can track that back through the history of the universe and see if that explains our history and it mostly does. Again, there's some questions there about the early first few bits. You might have read about like different measurements of the Hubble constant that we can't

quite reconcile. And that's what that's about is that level of acceleration, the same. same all the way through time or not. Is it or not? We think that it is, but we don't quite know that these measurements that we can't quite reconcile. I guess it's kind of the difference of whether dark energy is a constant, like a number in your equations of the universe, or is it a variable that somehow feeds in itself, or

that maybe has a little button that, you know, the makers of the universe are increasing. Exactly. Yeah. Right now we can describe it just using a number. It's a cosmological constant. We don't know where that number comes from or why it is what it is. We have really no explanation for it. But we can mostly describe the history of the universe using just a number for dark energy.

All right. Well, it sounds like the answer to the question of the episode is yes. It sounds like as far as we know, if things stay the same with dark energy, our super cluster of galaxies that we live in will be torn apart sometime in the future. That's right. So our more immediate cosmic neighborhood is safe and probably will eventually collapse into a black hole, but the Virgo cluster will not be in our neighborhood forever. Dark energy will take over and pull us apart from it.

It's going to be declustered. But we won't know, I guess, until the end of time. That's right. So we'll do our 5 millionth episode at the end of time, and we'll answer this question definitively. So maybe I shouldn't call you a person, Daniel, because eventually, who knows, maybe aliens will come and tear your part. We just have to wait and see before we call you a person. That's true.

From that point of view, none of us are structures. We could all be lunch in our future. Hey, fellow lunch meat. Ashes to ashes, dust to lunch. And lunch to something else once the aliens digest us. All right. Well, a pretty interesting lesson to think about not just like our place in the universe and how small we are compared to these enormous clusters of galaxies,

but also about the permanence of the universe. Like even something as huge as a supercluster Lanicaa, it may not be around. for the entire life of the universe. That's right. And think about these incredibly powerful, vast forces at play, tugging on these galaxies with millions and billions of stars all in a battle against dark energy.

It's really a very dynamical place. If you think about the universe and sort of fast forward, it's sloshing, it's frothing, it's doing a lot. All right, we hope you enjoyed that. Thanks for joining us. 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.

29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed. There's been a bombing at the TWA terminal, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, terrorism. 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. My boyfriend's professor is way too friendly, and now I'm seriously suspicious.

Wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota, luckily, it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend's 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. Hold up.

Isn't that against school policy? That seems inappropriate. Maybe. how it ends by listening to the OK Storytime podcast and the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hi, it's Honey German, and I'm back with Season 2 of my podcast.

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