Daniel and Kelly’s Extraordinary Universe - How Can We Tell The Distance To Stars?

Episode Date: January 17, 2019

How can we measure the distance to stars? Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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You mean we're like in the suburbs? That's right. You have to drive pretty far to get somewhere exciting from where we are in the universe. You know, if you look out into the night sky, it just looks black with little pinpoint, you know? Like, how do we know how far away these things are? Yeah, it's amazing. Some of these things we look at the night sky are pretty close by, you know, planets. Other things are incredibly distant, you know, billions of light years away. We are sitting on this little ball of rock floating through space

and we are making these huge statements about the structure of the rest of the entire universe. Like, how could we possibly know all this just sitting on this little tiny rock? Hi, I'm Jorge. And I'm Daniel. I'm a cartoonist. I'm a particle physicist, and this is our podcast called Daniel and Jorge Explain the Universe.

In which we talk about all the things in the universe. And how we understand them, or if we understand them, or actually most of the things that we don't understand. Today on the podcast, we're going to answer a question from a listener. That's right. Listener Ryan Lynn wrote in with a really interesting question. He said, how do we know what we know? A lot of times in science you hear about an amazing discovery or something science has figured out.

But this listener, Ryan always wondered, how do they know that? How do they figure that out? How is it possible to know such crazy facts about the universe given that we're stuck on this tiny rock in one little spot around the universe? Yeah, and just for the record, we may or may not have changed his name

to protect his identity. And he may or may not live at one, two, three, question drive at Atlanta, Georgia. Now, that's obviously made up. But yeah, if you have any questions, listeners, please send them to us. You can always write us at questions at danielandhorpe.com. So this is a very broad question. How do we know what we know?

But he had a very specific example, right? He asked, how do we know how far away the stars are? Yeah, which is a great question. Because as you look up in the night sky, a lot of the stars, stars look similar, right? They're just pinpoints in the sky. Yeah. And so you might ask, like, how can you tell which ones are close by and which ones are far away? In fact, your eyes sort of looks like they're all just painted on a ceiling, right? To your eye, to your brain, they just looked like they're painted on a huge dome roof. Yeah, and I think for many thousands of years,

that's what people thought. They thought they were looking up essentially the ceiling of their living room, right? And that the stars were painted on them. There was like a show. And it's very, you know, anthropentric that suggests that there's something created for us to experience when in fact of course it's a mostly cold empty universe that ignores and ignores us i'd love to live in that house where your living room is the size of the cosmos right but that's the thing they had no idea how big it was right they thought the sky was you know a few miles or a few hundred miles up there they had no concept at the scale of the thing they were looking at you know and that's the crux of the issue is that when you look up in the night sky you can't tell if something is really far away and huge or really close by and not actually that big. Right. Because if you look out into a landscape, you can see a mountain, and you sort of know how big mountains are. So just kind of by the size of how it looks, you can sort of guess how far away it is, right?

But a star is, it's like you don't even see it as a circle or a ball or nothing. It's just like a pinpoint of light. That's right. And that applies even for closer up stuff. Like I was talking with my kids about this question yesterday, and I told my daughter, you know, that the sun is much, much bigger than the Earth. It just looks small because it's far away, and she was surprised. She didn't realize that the sun was bigger than the Earth.

And, of course, we know now it's much, much bigger than the Earth, but in the sky, it seems a lot smaller than the Earth, which is huge, right, in our perspective. But it only looks that way because it's far away. And if you didn't know, like, well, how big is it, then you would have no idea. Is it enormous and far away or kind of small and close up, right? Yeah.

So this is a good question, and it's not an, easy question, right? And it's taken us a while to figure out how to tell how far away stars are. But before we talk about how scientists have done it, we thought we'd ask people on the street if they hadn't any ideas. Do people know how the distance to far away stars is measured? Or did they just take scientists at their word? Think about it for a moment. You know, how would you tell how far away a star is? Well, here's what people around the UC Irvine campus had to say. I have no idea how to tell that. No, I don't know that at all. You use a telescope?

I don't know. I'm stressed out, but I'm sure. I'm sorry. By some scientific TV show, something like that. Okay. Yeah. I think so. I don't know. How can we measure that?

I don't know, actually. Okay, great. Okay, so most people had no idea how this is done, which I love, right? And I could see in their faces when I asked them. They were all of a sudden, they thought, what? wait, that's a good question. I have no idea. Not only how you would, how scientists do it, but how you would even do it, right? Most of the people reacted that way. It's all familiar words, you know, how far away something, stars, you know stars. But when you think about it, like, it's really not that intuitive to know how far away a star is. Yeah, it's not that easy. Though I love that some people had ideas. Like, one guy's like, well, just watch scientific television shows and they'll tell you. Just listen to a podcast. I mean, that's what scientists do, right? You want to the answer to a question? Just just turn on science.

science TV and listen for the answer. Then you write it up in a paper. Yeah. It's like a snake eating its own tail. That's how all science is done. But the point is that it's not an easy problem and that most people don't know the answer. Yeah. Maybe we should start by talking about things that are close up.

Like, how do we tell how far away things are? Well, we have two eyes, right? So say, for example, somebody's throwing a basketball at you. How do you know how far away the basketball is? Well, one thing is you know how big a basketball should be. So as it gets bigger, you're imagining it's getting closer. But say somebody throws something at you you've never seen before. You're not familiar with, right?

How does your brain know how far away it is? The key is that you have two eyeballs and not just one. Yeah, so your brain looks at the difference between what your left eye and your right eye are seeing, right? Yeah. Yeah, so do this experiment. Hold out one finger in front of your face and then look at it with your left eye only, and then your right eye only, and you'll see it move, right? You get two different images, and you see a little bit different.

You see a little bit more of one side of the finger with one eye and a little bit more of the other side of the finger with the other eye, right? So you get its binocular vision, right? Binocular meaning two eyes. You get binocular vision, and your brain compares these two pictures. If these two pictures are really different, that means the thing is pretty close, right? Because you're looking at the thing from two very different angles, only if it's really close. But now move your finger as far away as your arm will allow, right?

Please don't chop off your finger and throw it across the room. Or if you're driving, pull over. If you're driving, then do this as a mental exercise, please, or pull over, yeah. So now with your finger further away, do the same thing where you look at it only with one eye or the other, and you'll notice that the two images look more similar. And as your finger gets further and further away, the two images look more and more similar, something that's really, really far away looks the same to both eyes, right?

Because the distance between your eyes gets really small compared to the distance to the object. Yeah, and it's more noticeable if you switch eyes very quickly, right? Like if you go blink, blink, blink, blink, switch between eyes, you can really see how things change the closer they are to you.

That's right. It also kind of makes you look like a crazy person. So if you're listening to this podcast out in public, you know, maybe get a little privacy. I'd love to imagine there's some car pulled over by the side of the road with a person blinking back and forth and somebody's now calling a homeland security

saying because of somebody's suspicious behavior right? Let's take a quick break. Imagine that you're on an airplane and all of a sudden you hear this. Attention passengers, the pilot is having an emergency and we need someone,

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Listen to America's Crime Lab on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. So yeah, that's called... Parallax, right? Which is not a comic book villain. It's like an actual technical term. Oh, man, this should totally be a comic book villain with like lots of sets of eyeballs or something. Parallax. Yeah, that's called binocular vision, right?

And or parallax. And the idea there is that you see from different angles if you have two views of it. So that works for your eyeballs because they're spaced fairly, they're spaced fairly wide, right? Right. It's kind of like a triangle, right? Like you draw a line between your eyes. And then another line, from each of your eyes to the object, you form a triangle, right? And that's how you, it's called triangulation for, because then with that triangle, you can tell how far away it is.

That's right. And that's why if you lose an eye or close an eye, you don't have very good depth perception, right? Because you need both of those views to see how far away things are. So people with one eye or people with an eye patch or whatever, you know, they stumble more often for this reason. Or they have to develop other techniques for knowing how far away things are. Yeah. So that also works for the stars, right? And maybe you're thinking, hold on a sec.

The stars are super duper far away, right? My eyes can't measure the distance to a mountain. How can my eyes measure the distance to the stars? It seems almost impossible. Well, what's happening when I look at the stars with my naked eye? Like, why can't I just resolve, use the same technique? Right. And the reason is that the distance to the stars compared to the distance between your eyes is almost infinite.

That triangle you talked about has a tiny little side which is the distance between your eyes and then the other two sides that extend all the way to the stars it's like light years and light years and light years so basically those photons are parallel to each other right

and do you see the same image? Technically your eyes see different images. It's just that maybe the difference is so small your brain and your eyeball can't tell the difference. Exactly so in theory if you had super duper vision, then maybe you could use that information to tell the distance to the stars.

Or if your eyes were really, really far apart. Exactly. If your eyes are really far apart, or you have really, really good vision, those are two ways to make this distance measurement more possible. So that's exactly what we do. To make our eyes further apart, we don't just look at the star up at the night sky. We wait for the earth to go around the sun, and we look at the star from both sides of the sun. So, you know, you look at the star in June, and you're on one side of the sun, and then the Earth goes around the sun.

You look at the same star in December. Now you're looking at the star from two astronomical units apart, right? It's as if your eyeballs were two astronomical units apart, right, on opposite sides of the sun. So that's pretty good distance. Yeah, it's like in December, you open your right eye and you look at the star, and in June, you open your left eye and you look at the star, and you compare how those two images are different. different. That's right. And I hope that you have things to do between December and June other than just standing outside waiting for six

months to open the other eye. Isn't that what scientists do? I thought that was great. It depends on how devoted you are to science, you know? People, if you really care about this stuff. No, that's exactly what it's like. And so you take one piece of data in one part of the year and the other piece of data in the other part of the year. And that's effectively

like making your head the size of the solar system. And so that's a huge additional leverage to, until to seeing things that are really far away. I wonder if that's how they measure how far the moon was. Do you know what I mean? Like maybe not waited until a whole half year,

but just kind of like look to the moon, talk to somebody who was a couple of miles away and see what the difference between what he saw and you saw, that would tell you how far away the moon is. Right. Well, there's a couple things there. One is the waiting part of the year won't help you with the moon because the moon moves with the Earth, right? We don't leave the moon behind.

And the moon is actually so close up that you can do cool stuff like bounce a laser off the moon or bounce radio waves off the moon to measure the distance. That's actually the best way to measure the distance to the moon. And what they've discovered, actually, is that the moon is getting further and further every year. We're losing the moon.

Like, the moon is orbiting the Earth, but the orbit grows very gradually, yeah. When are we going to lose the moon? Let's see, what time is it now? It's going to be a long time. We're going to have the moon around for a while. You don't have to worry about it. And if you've bought real estate on the moon, you're fine.

But I think by a centimeter a year's is the number I remember, the distance from the Earth to the moon is growing. That's not nothing. That's not nothing. But also the astronauts put mirrors on the moon when they landed there so that we can shine lasers at those mirrors and do cool tests. Oh, man. It's pretty awesome stuff. It's like a global selfie. That's exactly right.

Yeah. And so we're saying if you want to get better measurements of using this parallax system, you either need to have your eyes further apart, and what you do that is to the June and December, or you need better eyes. So, of course, we don't just use my eyeballs or Jorge's eyeballs or my grad students' eyeballs. We use telescopes, and telescopes out in space

that can tell the difference between really, really small images, right? They can look really, really far away and measure very precisely where these stars are at different times of the year. Yeah. I just think it's amazing that you can see something so far away. You know, like here on Earth, you're used to far away things looking blurry or faded or faint.

But just the idea that, you know, millions, trillions of light years away, you know, a photon left a star, traveled throughout the entire cosmos and then arrived into your eyeball, right, when you're looking at the night sky. That's one of my favorite things of the night sky is that it's the world's greatest view. It's the universe's greatest view. You know, you are seeing across billions of light years of space. It's amazing to me. I totally agree that those photons traveled unimpeded for so long

and then finally just get absorbed by your eyeball. And then you just sort of glance away, you know? Yeah. Okay, so then what are other ways? How do we tell how far away things are beyond a few thousand light years? Well, that's really the best method we have is this parallax method. And so science has been working on that really hard. And it's actually cool because our ability to do this is improving pretty rapidly.

I mean, it used to be we could only see things to like maybe a thousand, 1,000 light years away. Then we got better telescopes, and now we can see things pretty reliably up to several thousand light years. And now that we have even better telescopes, we're seeing some things up to like 10, 15,000 light years away. So as we get better and better telescopes,

we're going to get better and better measurements of this. And parallax is really the crux. That's the way that we really believe that it gives us the most reliable estimates of distance. So everything is built on that. Beyond that, when things are further away, then there's, you know, fuzziness, there's questions,

and people out there might get a little skeptical as how do we know some of these things. But essentially, what you need to do is what we talked about earlier is find something that's a reference point. Find something where you know how bright it is. So you can tell... Like a mountain, like you know how big a mountain

typically is. Yeah, exactly. Yeah, so if somebody was, for example, standing on a mountain and shining a really bright light, and you knew how bright that light was at the source, then you could measure how dim it is where you are, and you could tell the distance, right? Because the brightness falls like one over the distance squared.

Because the photons go out in every direction. And the surface area of a sphere around the star goes like radius squared. And so the same amount of light is spread over more and more area. You just get fewer of those photons, the further away you are. Even with like no atmosphere, no air between you. That's right. Things just spread out. And so as you said, we get just a little stream of those photons. Most of the photons from stars are going somewhere else, right?

Somewhere else in the universe, an eyeball, we hope, is picking up one of those photons. So we're only seeing a tiny little slice of the photons that come from that star. So as we were saying, if you want to know how far away something is, you have to know how bright it was originally, how bright it is at the source. And then compare that to the brightness you're measuring on Earth. That's pretty tricky because the universe is filled with weird stuff that we don't understand, right? And so it's sort of chicken and egg, right? You want to know how far away is that stuff, and what is it? Well, you don't know either one, you're sort of in a pinch.

It just looks like little dots. It just looks like little dots. But we found a few things that we can use for reference points. But maybe let's take a break, and we can dig into that in a moment. Imagine that you're on an airplane, and all of a sudden you hear this. Attention passengers. The pilot is having an emergency, and we need someone. Think you could do it?

It turns out that nearly 50% of men think that they could land the plane with the help of air traffic control. And they're saying like, okay, pull this, until this. Pull that, turn this. It's just... I can do it my eyes close. I'm Mani. I'm Noah.

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Listen to the Good Stuff podcast on the Iheart Radio app, Apple Podcasts, or wherever you get your podcasts. Okay, so what are the other ways we can tell how far away starts? are. So one of the ways is with these really weird kind of stars that are variable stars that don't shine the same amount of brightness all the time. And the reason is that, well, there's some really complicated astrophysics that's beyond me, frankly. But the thing that's important to know is these stars, which are called ciphyids, they pulsate. And the rate at which they pulsate is very closely connected to their brightness. So if you can measure how fast they are

pulsating, you can know their brightness. It's got this internal layer that stores and releases energy so that the whole star expands and contracts, and that's what makes it pulsate. Kind of like a lighthouse. Yeah, just like a lighthouse, exactly. It's just like a lighthouse. So these things are like lighthouses out there in our galaxy

and in other galaxies. And people figured out by using parallax that the ones that are pretty close up, that there's a relationship between how bright they are and how fast they pulsate. And that's really cool, because then there are ones that are really far away where we can't use parallax

to tell how far away they are but we can tell how fast they are pulsating right that's not hard to measure you just watch it and you see blink on and off you can then say you know how bright it is at the source if you know how bright it is at the source and you know how bright it is here on earth then you can do some simple math to figure out

how far away it must be it's like it's telling you using Morse code how bright it is right like I'm really bright I'm really dim. Yeah, and that's the key. These things are called standard candles, and they're just ways to know how bright something is at the source

without knowing how far away it is, right? That's the key. You have to have some other way of knowing how bright they are. And so these were discovered almost 100 years ago, and it was Hubble himself, Edwin Hubble, who used these and found a bunch of them that were surprisingly far away. He looked up in the night sky, and back then people thought the whole universe was just the Milky Way galaxy,

That was it. There was just a bunch of stars and our galaxy and nothing else, right? Like it was all concentrated around us. Yeah, they thought that was the whole universe. And even that was mind-blowing to people, right? If all you thought was, oh, it's just the earth and a few other planets

and everything else is sort of painted on the living room of the sky, then it's mind-blowing to think, what, there's a whole galaxy of zillions of stars, right? So people were just slowly accepting that. And then Hubble, he looked to try to measure these Siphyids

and see how far away they were. And he got some really weird results. He got results that suggested that these things were crazy far away, far away than any star anybody had seen before. And so he thought, well, maybe these things are not just like weird nebula or weird other stars.

Maybe there are other galaxies. And that must have been a mind-blowing moment for him, right? Wow. It's like it's not just us in our living room. There's other houses around us. Exactly. Exactly. And that's what I love about this question

is figuring out how far away the stars is gives us a 3D map of the universe, right? It tells us where everything is, what is the structure, where are we living? Are we in the suburbs? Are we in the exciting downtown hip area of the universe, right? So it's so important. And it's exactly what's led to these moments of realization

where you discover that the universe is totally different from the way you thought it was. I hope to have one of those moments myself in my science career. It's let us map the universe and where we are in it. Exactly. That's a big deal, right? That's a huge deal. And that really was the birth of modern cosmology, you know, knowing there were other galaxies and wondering how many are there and how did this all come together?

And, you know, and obviously, if there are other galaxies, then maybe we're not the most important one or at the center of anything or all those questions were created just at that moment when we discovered that there were other galaxies. Okay, so that's a really cool trick, is find an astronomical. object that somehow tells you how bright it is, not by how bright it is, but through some other information. Yeah, exactly. And so you have to really know the astrophysics of it. And the sephiades were calibrated

by comparing to the parallax scale. So parallax works up to maybe 10,000 light years. And in that sphere, there are some of these stars, these variable stars. Oh. So once you know that, then you can look at the ones even further out using this technique. Exactly. Exactly. And astronomers

call this the cosmic distance ladder because there's a bunch of different techniques that you use for things at different distances and then you try to overlap them and stitch them together. There's no one technique that will work for everything. For really close-up stuff, you've got parallax, for stuff that's a little further away. You've got these

variable stars and sephiads. And then after that you have to use GPS. After that, you just watch a science TV show and they tell you. That's the answer to everything. The problem is that sephiids are just stars and so they're bright, but they're not that bright. And you want

to see something like in another galaxy or really, really far away galaxies? You can't resolve individual stars in super-duper far-way galaxies. So that has a limit, too. Yeah. So then they needed something super crazy bright to serve as a standard candle for the rest of the universe.

Because these stars, even though they blink, they get lost in the light from the rest of the galaxy they're in. Yeah, exactly. They're not particularly bright kind of stars. Okay. And so that's why the end of the cosmic distance ladder is dominated by

supernova. Supernova is when a star goes boom, right? When it's time to check out, it's had all of its fun, and it's decided we're done with all this fusion stuff, let's just blow it on one last big party. It collapses, basically, right? Like, it runs out of fuel, and then it just

Yeah, and we did a whole fun podcast episode on how stars end their lives, which you should go out and listen to as you're interested in that kind of detail, but the critical thing is that one kind of star ends in a very particular way, and it's called a type 1A supernova. These supernova are extraordinarily bright.

The thing you have to understand is that the star is like using up all of its fuel in a very short amount of time, and so it's extremely bright, and a single supernova can be brighter than the entire galaxy that it's in. So that's how we can see it. I mean, if you look at the night sky, you can see these little fuzzy things that are the other galaxies, but you can't really resolve any particular star in it, right? Well, for the close-up ones you can, like for Andromeda. Which is one of the nearest galaxies.

You can see the shape of it. You can see individual stars. But you're right. For the furthest ones, they're just little smudges, and you can't resolve individual stars, except when one of them goes boom, and then you can see it. And it's brighter than the hundred billion stars combined, right? It's incredible to me how bright these supernova are. And you don't want to be close to any of these things, right?

Anybody near these things gets instantly sterilized. So we would see it as a little dot inside of a galaxy, which is flash. it will just pucho. Yeah. And in the night sky, you see it as maybe a new star, right?

There could be like a little smudge there you never noticed from a really far away galaxy and all of a sudden there's a bright star there. And you can look back in history and see the record where ancient peoples saw

these things in the night sky, right? We have a history of supernova explosions that goes back more than a thousand years because like Chinese astronomers noticed, hey, on this date a new star appeared in the sky and it only lasted for three weeks

and then it was gone. Boy, that was weird. And the trick is that these supernova are always the same, right? It's not like you have small supernovas and big supernovas. It's like if you're going to have a supernova, it's always this bright. Well, there are a lot of different kinds of supernova, but this one kind called Type 1A always has the same sort of curve, this light curve. We talk about how bright it gets, then it hits a peak brightness, and then dims away.

And the whole process lasts days, but it always has the same shape and always has the same peak brightness. Right. Now, for those of you who know a lot about this, there are some technical details in the variation of the peak brightness, but that can get calibrated away, and we can talk about that another time. But the basic version of the story is that they always have the same peak brightness because it's always the same kind of process.

It's always the same size star with the same amount of fuel in it. It's not like every star goes supernova. It's like only once with a particular size and stuff in it will collapse at some point, right? In a very particular way. That's exactly right. There's lots of different kinds of supernovae. But one kind, which comes from binary star systems in which one of them is a white dwarf, that leads to type 1A supernova. Oh, wow.

And that just happens to be very regular. And it just happens to be very little variation between the brightness of different type 1a supernova. And this is something people realized, you know, like 20, 30 years ago. But it took some work. You know, people are constantly out there looking for new ways to find distance metrics, new ways to figure out how far away things are. And people were working on Type 1A Supernova and other people were working on this kind of thing. So we work on the other kind of thing. People today right now are working on new ways to measure distances because we always want to know more precise information.

So behind the scenes, grad students were slogging away. Can we figure out how far away Type 1 supernova are? Can we calibrate their light curves so that they all look the same? And then about in the late 90s, people figured out how to do it and the technology became possible. and they started collecting this information. Right. And so all of a sudden, a whole new window into the universe. We could tell how far away things that are super far away were

because these supernova are so bright. Right. But it's sort of interesting because it came from kind of a random occurrence in the universe, right? Like people just cataloging and observing supernova just for the sake of science, suddenly they realized this gives us a tool for mapping the universe. Exactly. And that's what astronomy is all about. It's like, let's figure out how to use the idiosophers.

synchresies to the universe to give ourselves clues, right? And so, yeah, it's just luck, right? I mean, it's luck. Like, what is it revealing that we, that's underneath the surface? Exactly. That is, that is pure science right there. It's like, let's nail down facts about the universe by things that accidentally reveals to us. I mean, everything the universe tells us is an accident, right?

Nobody's purposely sending us information. We're just sifting through what we see, unless we're living in a simulation, in which case, everything is on purpose. Yeah, so type 1A supernova extend out really, really far. The best distance measurements we have come from type 1A supernova. So there's sort of a three-step ladder there. There's the parallax for close

up stuff, the sephiids for medium range stuff, and then the type 1A supernova for super far away stuff. And they overlap, which allows us to calibrate. And it's built one on top of the other, right? What we know from supernovas is built on what we know from these

blinking stars, which is built on what we know about from parallax, which is built on our eyeballs. That's right. Exactly. It's built on our listeners' eyeballs. And now we actually have a new way to measure distance, which is really cool, which has only been possible recently. And that's from gravitational waves. Gravitational waves are these ripples in space time that we can measure by seeing how these observatories shrink and expand by minute distances as the gravitational wave passes. And just like with type 1a supernova or with sepheids,

we know something about the strength of the gravitational wave based on what it looks like here, based on not on its brightness, but like on how fast it's wiggling. Because gravitational waves wiggle, right? They're waves of space. So something about how they're wiggling gives you a clue as to how bright,

how intense they were at the source. And then we can, by measuring, how the intense they are here, we can tell how far away things were. So this is a whole new handle we only recently added to our cosmic distance ladder. Wow. You sound pretty excited about gravitational waves. I am. I am. It's a heavy topic. But it's kind of cool, I guess, just taking a step back,

just to think that we went from like a 2D view of the universe, just looking at these things that we thought were painted on the ceiling, to this now really sort of incredibly rich and deep 3D conception of the entire cosmos, right? It's absolutely incredible. And it's more than 3D, actually. It's actually kind of like 4D because when we look out into space, we don't just look out at where things are.

We look out at where things used to be, right? So we see things in sort of these spheres, like the things that are nearby are recent, things that are far away are old. And so we're not just looking out at where we are in the universe, like a 3D map. We're looking at these shells that get further and further back in time. And so this allows us to see what the universe used to be like.

So absolutely it gives us a sense for the structure of the universe, but also gives us a sense for how that structure is changing. And why you cannot get more rich information about the formation of the universe and our context and why we're here and all that crazy important stuff than understanding how the universe came to be the way it is, right? All that just from looking up. That's right. So next time you're looking at the night sky, I wonder,

is there more information there than I'm seeing? If there are more information than even scientists know? What will future scientists laugh at us for missing? Yeah. What's going to be in those future science shows? What's going to be on a future science podcast? All right. Thank you very much for listening.

And thank you to Ryan for sending this question. Thanks for listening. See you next time. After listening to all these explanations, please drop us a line we'd love to hear from you. You can find us at Facebook, Twitter, and Instagram at Daniel and Jorge, that's one word, or email us at Feedback at Danielandhorpe.com. I'm Dr. Joy Hardin-Bradford, host of the Therapy for Black Girls podcast. I know how overwhelming it can feel if,

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