Daniel and Kelly’s Extraordinary Universe - Why black holes are actually bright.

Episode Date: January 6, 2022

Daniel and Jorge talk about the incredible, ironic brightness of black holes. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

This is an I-Heart podcast. December 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. It's important that we just reassure people that they're not alone, and there is help out there. The Good Stuff podcast, Season 2, takes a deep look into One Tribe Foundation, a nonprofit fighting suicide in the veteran community. September is National Suicide Prevention Month, so join host Jacob and Ashley Schick as they bring you to the front lines of One Tribe. tribe's mission. One tribe, save my life twice. Welcome to season two of the Good Stuff. Listen to the Good Stuff podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast.

From tips for healthy living to the latest medical breakthroughs, WebMD's Health Discovered podcast keeps you up to date on today's most important health issues. Through in-depth conversations with experts from across the health care community, WebMD reveals how today's health news will impact your life tomorrow. It's not that people don't know that exercise is healthy. It's just that people don't know why it's healthy. And we're struggling to try to help people help themselves and each other. Listen to WebMD Health Discovered on the IHeart Radio app or wherever you get your podcasts. Hi, it's Honey German, and I'm back with season two of my podcast.

Grazias, come again. We got you when it comes to the latest in music and entertainment with interviews with some of your favorite Latin artists and celebrities. You didn't have to audition? No, I didn't audition. I haven't auditioned in like over 25 years. Oh, wow. That's a real G-talk right there. Oh, yeah.

We'll talk about all that's viral and trending with a little bit of cheesement and a whole lot of laughs. And, of course, the great bevras you've come to expect. Listen to the new season of Dacias Come Again on the I-Heart Radio app, Apple Podcast, or wherever you get your podcast. Hey, Jorge, I have a podcast. top quiz for you.

Uh-oh. Was this in the syllabus? Did you read the syllabus? No. Then there was one. Then yes, it was on the syllabus. All right. That sounds fair.

All right, hit me up. What is the object that astronomers call a blonet? Interesting. Sounds like a blah internet? Maybe like the less exciting version of the internet? Close. Try again. All right.

Well, it's astronomy, so I'm guessing maybe it sounds like planet. like planet, but maybe it's like a black planet or a, or I don't know, like a black hole planet? Ding, ding, ding. You get 100%. It's a planet that orbits a black hole. Oh, interesting. So sometimes the astronomy does come up with sort of names that make sense. Sometimes it's being generous. Just be glad I didn't ask you what a plunit is. I'm glad you didn't ask me what a poonet is. Wait, is a plunate a real thing? Absolutely. Is it a more pluish version of the internet?

Hi, I'm Jorge, a cartoonist, and the creator of PhD comics. Hi, I'm Daniel. I am a particle physicist and a professor at UC Irvine, and I would never joke about plunits. Does that make you a plufressor? I always try to tell the pluth. Well, that's a real pluce. But plunets are a real thing. Really? What are they? What's a plunet?

A plunit is a moon-turned planet. It used to be a moon orbiting a planet, but then it was set free and is now wandering the solar system and counts as a planet. Oh, interesting. So you inserted the word moon inside of the planet. Interesting. You didn't, like, combine it or you like literally merged it. Yeah, exactly. You know, take the old job and insert inside.

the new job. So, for example, you know, your job would be car engineer tunist. Engineers, I like that one a little bit better. Engineers, there you go. Engineerist. There you go. Anything that involves ingenuity. And you're no longer orbiting anything. But welcome to our podcast, Daniel and Jorge, Explain the Universe, a production of IHeart Radio. In which we mash up all of the crazy ideas that are out there in the universe, the planets, the moons, the plunits, the blonets, the black holes, the neutron stars, the quasars, the tiny little particles, and even the hypothetical stuff that

might not exist, all in a desperate attempt to understand this glorious and incredible universe that we find ourselves in that provides us with so many satisfying, deep, rich, and cosmically contextual questions about the nature and meaning of our lives. Cosmically contextual questions. That's a great alliteration there. It's positively pluish. I'm an aspiring alliterationist. But it is an incredible and wonderful universe out there full of interesting things that we've named, that we haven't named, things that we understand and things that we have yet to understand and that we have yet to understand and that we'll hopefully learn more about in the future. That's right. It's a never-ending journey to answer the questions about the universe. Jorge asked me earlier, if somebody is once a physicist, if they're always a physicist. And I think that the answer is that everybody out there is a physicist because we all want to know answers to the deepest questions of.

about the universe. Yeah, we all have questions. We all wonder about the world around us. And I guess that makes you a physicist, right? I mean, technically anyone who wonders about the universe and how it works is sort of a scientist, right? Yeah, physics is just trying to tell mathematical stories to answer our questions about the universe.

And we all have those questions and try to build in our heads models about how the universe works. Professional physicists who do it for their day job, take it one step further and devote their lives to it. But I think it's something that everybody in some level is doing. Interesting. Does that mean you go around saying, hi, I'm a pro physicist. Stand back. I'm a professional. That's right. Like professional wrestlers, you need to take

professional physicists much more seriously. Yeah, I'm sure you get paid as much as professional athletes as well. You should see me in costume. Yeah, and I'm sure there's an NPA also in National Physics Association, right? You have a world championship too? Oh, yeah. We call it a smackdown also. Right? Like you and the people in your department, you're sort of a team and you're sort of competing against other teams in a way, right? To uncover the secrets of the universe. That's true. We do have a group here at Irvine that all sort of works together, probing the universe in different ways, plasma physics, condensed matter physics, all the way to astronomy. I'm also a member of other teams like I'm a member of the Atlas Collaboration, which is a group of thousands of scientists all working together to try to understand the basic constituents of matter. and we have competition.

The CMS collaboration is like 5,000 other scientists trying to beat us to the punch. Interesting. How many teams are you a part of that do? Sounds like you're very promiscuous businesses. I'm a prolific collaborator. That's true, yes. You're a professional prolific promiscuous businesses. That sounds very positive.

Well, I'm pro you anyways. But yeah, it is an interesting universe full of mysterious things. And nothing is more mysterious, it seems, than an interesting object that we thought was theoretical for a long time. but that we now have pictures of out there in the cosmos. Maybe the most challenging thing to wrap our minds around to understand that it might really be out there in our universe, not just a product of mathematical calculations, but a reality, something one could actually fall into and experience, something one could actually see with their own eyes, are these weird, mysterious corners of space, black holes, where

gravity and space time are so intense that nothing, not even light, can escape. Yeah, and they are frustrating to think about and to wonder about because they are literally sort of hidden from the universe. They are not just black holes in names. They are actual sort of holes in the fabric of space time and reality itself. Yeah, they're almost like a separate universe. They are detached from our universe. Once you fall into a black hole, it's not that you can't escape because you can't go fast enough or because of the limit of the speed of light. It's because the shape of space is so crazy, so distorted, so curved that they are one directional.

that every path leads you towards the center. So in some sense, everything inside the event horizon is like its own little universe. It's detached from normal space time. Yeah, whatever happens in a black hole stays in a black hole. You can do whatever you want. You can relive your wild days inside of a black hole. That's right. The original Las Vegas of the universe.

Yeah, Las Vegas is sort of a black hole if you think about it, at least for people's money and prudence. That's right. It leaves a black hole on their hearts. Yeah, black holes are super mysterious. They seem to sort of occupy a big hole in people's curiosity. It's one of the things we get asked about the most on our social media and through email. That's right.

And it's not just you folks out there who are super curious about black holes and what's inside of them. Professional physicists, experts in relativity and quantum mechanics are also desperately curious to know what's inside a black hole. Because at their hearts, they might contain the answer to one of the biggest open questions in physics, which is how gravity and quantum mechanics work together, or if they do. Gravity and quantum mechanics are our two pillars of understanding the universe, but they have very, very different pictures about how the universe works. But most of the time, we only need to use one of them, gravity or quantum mechanics. It's inside a black hole that both of them are needed,

but unfortunately we don't really know what they are doing together inside the black hole because, of course, it's hidden from us. Yeah, those secrets are locked inside. of black holes and we may never get to them because nothing not even light escapes a black hole. And yet somehow ironically or interestingly, black holes are some of the brightest things in the universe. Black holes are not completely dark. That's right. And we hope that by studying what happens outside a black hole in the neighborhood of a black hole, the things the black hole does to the space and objects around it, perhaps we can start to get a glimmer of what's going

on inside. So to the end of the program, we'll be asking the question. What makes black holes glow? Interesting. You mean like glow from light or just they just have a positive disposition about it? Their career arc is just incredible. They just get bigger and bigger and bigger. Sucking in more attention as they go along. That's right.

They go from D list to C list to B list and then finally A list as in astronomical stars. Yeah, not B list like black hole. But yeah, black holes are soon. Super interesting because they are mysterious and they trap even light itself, but also they glow, right? They sort of glow out there in the universe. Sometimes they are even some of the brightest things in the night sky. Yeah, and we have been looking at black holes for almost 100 years without knowing it. Some of the things that we've been studying for decades and decades and decades we only recently discovered are actually black holes. Yeah, so they're not just sort of sitting out there in space, sucking stuff up and looking dark and mysterious.

They also sort of shine brightly and at least some of them give off a. crazy amount of radiation. That's how we sort of know where they are. So as usual, we were wondering how many people out there had thought about the glow of black holes or whether they even knew black holes glowed brightly. So Daniel went out there into the internet to ask people, why do black holes glow so brightly? And we are very interested in hearing you speculate without preparation on topics for future episodes.

So if you'd like to participate, please send us your name to questions at danielanhorpe.com. We'll send you the questions back over email. You can record the answers in your very own home. It's easy. It's fun. Don't be shy. So pop quiz, why do you think black holes glow? Here's what people had to say. They glow so brightly because they're sucking all the surrounding light and everything around it. So you have spires of light basically coming in at one point and that's why it's so bright.

I don't think that the black holes are glowing like. at itself, definitely not the at the center, since there's the gravitational pull there is so great that not even light can escape it. However, you can potentially detect material around them, like gas and dust spinning around it, throwing off hot material and when emitting radiation, like x-rays, and as matter falls into the hole, it can be detected and it can actually brightly or glow brightly. I think there's so much energy. imparted into the material that's warming around them

that somehow that energy turns into light excited electrons and stuff like that and I also know that they can focus material and jet it out and that material goes out and interacts with the dust and stuff around the black holes

and bumps them up into a light emitting excited state like an emission nebula Okay, so black holes, they're not glowing. I think that the light is getting refracted around them. It's getting bounced off. And so it's not the black hole that's glowing, but it's an illusion almost. Because they're, I believe, they're called accretion disks, give off just a ton of heat

because they're swirling around at almost light speed, something like that. I think not the black hole itself glows. What it glows would be the creation disks where all the gases at that speed emit energy and also might be the Quassars. Some black holes have Quessars. That would be also a reason. why a black hole look so brightly

I think this has to deal with black holes that are feeding that are actively feeding off of other stars or other objects I think when they're feeding it brings in everything on the accretion disk and everything heats up and creates like plasmas

where like they're stripping you know stripping everything down to its elemental form and I think it causes a lot of activity like the electromagnetic field so like I know black holes give off x rays and they give off gamma rays and they give off these strong energies

that we can measure here on Earth. So it has to be because the black holes give off energy because they're feeding off of surrounding objects and causing a lot of activity in ways that we can measure here on Earth. All right, some pretty good answers. A lot of people seem to be confident and familiar about this topic.

Almost like we've been talking about black holes for quite a while on the podcast. Yeah, for 340 episodes apparently. It is a popular topic, and a lot of people hit on a really important point, which is that a lot of the radiation from black holes doesn't come from the actual black hole within the event horizon itself,

but from the stuff that's around the black hole, the impact of the black hole on neighboring objects. Right, yeah. Or maybe they read both of our books and our two books. We have no idea and frequently ask questions about the universe. We do talk about black holes, and one of them we get really into black holes, like literally. Yeah, we talk about what it would be like to fall into a black hole,

whether you could survive and what you should pack along the way. Yeah, and what you'll experience. So please check out our books, Our second book, Now Out, Frequently Asked Questions About the Universe, but in this case, we're talking about why they glow. And a lot of people seem to associate it with not the black hole itself, but sort of the things around it, or at least what's happening around it in terms of the space distortion.

Yeah, and there's several effects here that are important to pull apart. One is whether black holes actually do glow themselves. And the second are how they make things around them glow, but there's more than just the accretion disk there, which we'll get into later. But first, let's talk about the black holes themselves. Most people said black holes don't glow because they're black. That's mostly true, but not actually 100% true. A black hole, even if it had nothing around it, just sitting in empty space, wouldn't be 100% black.

They do give off a very small amount of radiation. Yeah, super interesting. And so let's dive into this topic and make it glow. So, Daniel, I guess to refresh everyone out there, what is exactly a black hole? A black hole is a region of space where it is curved so much that not even light can escape. So this portion of space is then encircled by something we call an event horizon. Any object or photon or particle which falls within this event horizon is trapped forever. It moves towards the center of the black hole.

And this event horizon is not like a physical barrier. There's nothing there. There's nobody to greet you or to say hello and welcome to the black hole. It's just sort of a region of space which if you pass, you will never escape. So these black holes are these curved regions of space time, as we said earlier, sort of detached from the rest of the universe. And they form when stars collapse or sometimes they form at the center of galaxies

and they can be extraordinarily massive. Yeah, and we've talked about how you can have them of any size. You can have tiny little mini black holes, or you can have giant black holes that are billions of times more massive than our sun. And like you said, there's sort of regions of space where suddenly, like everywhere you can go can only go take you inside of the black hole right it's sort of a weird thing to think about that space can bend that way yeah and space is something you might think of as just sort of like the backdrop of the universe like the stage on which events happen but we now know that it's much more

interesting and it can do fascinating things like bend and twist most of the time you don't notice that gravity turns out is an effect of space's curvature so you feel that every day when you walk around on the planet but mostly things seem to move in a way that makes sense to you but a black hole's like the extreme version of that, like crank it up to 11, where things get really distorted and the shape of space like dominates. You know, it's the thing that determines everything that happens. Right. And I guess specifically you mean like the shape of space time, right? Like maybe it's not so much space, but space time, meaning like where you will be in the future in that space. Yeah, we bundle space and time together into a sort of a four dimensional object. One thing that's really fascinating is

that inside the black hole, space becomes one directional. You can only move towards the center of it. That seems a little counterintuitive until you remember that outside the black hole, time is already one directional. The way you can only move forwards in time, in that same way, inside the black hole, every path leads towards the center. The future of every particle trajectory inside a black hole hits the singularity. So that's what we mean when we say that space is one directional. And that's directly because space is curved so much. So once you're inside of the event horizon of a black hole, you can't get out and not even, you can't even shoot a laser out of it because the light from the laser would just shoot back around and come back to the center of the black hole. And so it's sort of surprising that a black hole can glow then.

So like how do they glow? How can they give off or emit anything? Yeah, black holes can glow. And the way they do that is by hawking radiation. Hawking radiation is the recognition that black holes have a temperature. Like everything else in the universe almost has a temperature. I have a temperature, you have a temperature, the sun has a temperature, and everything that has a temperature and has electromagnetic interactions glows. It just sort of like gives off heat.

The way, for example, a pie sitting on your counter cools off. It does that by radiating away some of its energy. So this is called black body radiation. And we talked about this on the podcast recently, how everything with the temperature glows. So Stephen Hawking realized that black holes also have a temperature. They're not at absolute zero, which means that they must go. glow. And so he speculated that they must give off very faint radiation, meaning little particles created just outside the black hole that somehow steals some of its energy. And there are various

sort of pop-side descriptions of how hawking radiation happens at the edge of a black hole. But it's important to understand that none of those are really very accurate. We have no accurate microscopic picture of how hawking radiation really happens because it requires a theory of how gravity affects particles. And we just don't have that theory. We don't know. what quantum gravity is. We can't describe the effect of gravity on tiny particles.

There are some sort of hand-wavy explanations to give you a sense of how it works, but it's important to understand that mostly it's a statistical argument about the temperature of black holes. Right.

Yeah, it's pretty cool to think about hot black holes or cool black holes. But I guess, you know, most people are sort of familiar with a pie on your desk kind of emanating heat through the air. But I think what's interesting

is that even if you put that hot pie out in space where it's not touching any air, it would still radiate heat in the form of infrared light, right? Yeah, or visible light depending on the temperature, like the sun. There's a huge vacuum between us and the sun, but it's still able to warm you up on a nice, toasty Southern California morning, and it does that by radiating away its energy via photons.

And the frequency of those photons depends on the temperature of the object. So the sun glows in the visible spectrum, the Earth and you glow in the infrared, as does that pie. Black holes are very, very cold. So they glow in very, very long wavelengths. Yeah, but it's kind of interesting because, you know, that hot pie in space is probably, you know, the way that it's emanating light is that, you know, the electrons and the surface of the pie are excited and they drop down an energy level maybe and they emit a photon in the infrared. So you can sort of imagine that mechanism for giving off energy. But a black hole is kind of weird, right?

Because the surface of a black hole is not actually like a surface and it's not actually like stuff, right? It's weird to think that it can just emanate heat or light out of basically, you know, a hole in space. Exactly. It is very weird. And as you said, we have a pretty good understanding for how that happens for pies. Like the physics of pies, we have a pretty solid understanding, like quantum pie dynamics, pretty well understood. But that's because we understand that kind of matter. And the forces of gravity there are pretty weak. But in the case of a black hole, we don't really understand what happens to electrons very, very close to the event horizon.

or virtual particles created near the event horizon. We just don't have an understanding of it. Neither does Stephen Hawking. He doesn't have a theory of quantum gravity. What he did was make a sort of like semi-classical theory of gravity, like a sort of patched together concept of, you know, using bits and pieces to sort of approximate what some elements of quantum gravity might look like. And using that, you can make a sort of hand-wavy picture.

You know, the picture is that you have virtual particles created outside the event horizon, and not within the black hole, but outside. And those particles can pick up some extra energy because of the incredible gravity of the black hole. Remember that black holes, even though they have this event horizon, they can affect things outside the event horizon, right? Just like the sun pulls on you with its gravity from very, very far away. A black hole can also do that,

pulling on you with its gravity and giving you extra energy. When it does so, it loses that energy, it gives that energy to one of those particles. So if a particle is created near a black hole, and then boosted by the energy of that black hole, when it leaves, it's taking away some of the energy of that black hole. So again, this is a hand-wavy, probably not accurate description of how hawking radiation is generated

because we don't have a solid understanding of quantum mechanics and gravity and how they play well together. All right, well, let's dig into this hawking radiation a little bit more. And then also, what are some of the other ways that black holes glow? Some of them are pretty dramatic and maybe even the brightest objects in the universe. So let's get into all 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. Hey, sis, what if I could promise you you never had to listen to a condescending finance bro? Tell you how to manage your money again. Welcome to Brown ambition. This is the hard part when you pay down those credit cards.

If you haven't gotten to the bottom of why you were racking up credit or turning to credit cards, you may just reclass. create the same problem a year from now. When you do feel like you are bleeding from these high interest rates, I would start shopping for a debt consolidation loan, starting with your local credit union, shopping around online, looking for some online lenders because they tend to have fewer fees and be more affordable. Listen, I am not here to judge. It is so expensive in these streets. I 100% can see how in just a few months you can have this much credit card debt when it weighs on you. It's really easy to just like stick your head in the sand. It's nice and dark in the sand. Even if it's scary, it's not going to go away just because you're avoiding it.

And in fact, it may get even worse. For more judgment-free money advice, listen to Brown Ambition on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I had this like overwhelming sensation that I had to call it right then. And I just hit call. I said, you know, hey, I'm Jacob Schick. I'm the CEO of One Tribe Foundation. And I just wanted to call on and let her know there's a lot of people battling some of the very same things you're battling. And there is help out there. The Good Stuff podcast Season 2 takes a deep look into One Tribe Foundation, a non-profit fighting suicide in the veteran community. September is National Suicide Prevention Month,

so join host Jacob and Ashley Schick as they bring you to the front lines of One Tribe's mission. I was married to a combat army veteran, and he actually took his own life to suicide. One Tribe saved my life twice. There's a lot of love that flows through this place, and it's sincere. Now it's a personal mission. Don't want to have to go to any more funerals, you know. I got blown up on a React mission. I ended up having amputation below the knee of my right leg and a traumatic brain injury because I landed on my head.

Welcome to Season 2 of the Good Stuff. Listen to the Good Stuff podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Hola, it's Honey German and my podcast, Grasias Come Again, is back. This season, we're going even deeper into the world of music and entertainment with raw and honest conversations with some of your favorite Latin artists and celebrities. You didn't have to audition? No, I didn't audition. I haven't auditioned in like over 25 years. Oh, wow.

That's a real G-talk right there. Oh, yeah. We've got some of the biggest actors, musicians, content creators, and culture shifters, sharing their real stories of failure and success. You were destined to be a start. We talk all about what's viral and trending with a little bit of chisement, a lot of laughs, and those amazing vivras you've come to expect. And of course, we'll explore deeper topics dealing with identity,

struggles, and all the issues affecting our Latin community. You feel like you get a little whitewash because you have to do the code switching? I won't say whitewash because at the end of the day, you know, I'm me. But the whole pretending and code, you know, it takes a toll on you. Listen to the new season of Grasas Has Come Again as part of My Cultura Podcast Network on the IHart Radio app, Apple Podcast, or wherever you get your podcast. All right, we're talking about glowing black holes, which it sort of sounds like an oxymoron, sort of like a bright, dark object. I think it's sort of cool that we think about black holes is, like, hidden and hard to find, and it took us decades to discover them.

When it turns out, they're sort of like screaming about their existence all the way through the universe. Like, they are not being shy. They're being very, very obvious. They're kind of obnoxious, actually. It's like, can you quiet down, please? We're trying to study black holes. Settle down. settle down. We know you're cool, but

you know, you don't need to prove yourself. And that's what makes it ironic is that they are so bright and so intense and so crazy that people sort of overlook them as candidates for black holes for a long time. Interesting. Well, we were talking about hawking radiation, which is sort of the glow or

a small glow that black holes have that happens sort of at the boundary of the black hole due to quantum particles appearing and things like that. But I guess the question is, if all of this is theoretical, we don't actually know how it emits hawking radiation. And I'm guessing we've never seen this hawking radiation being emitted because we barely have pictures of black holes. Like how do we know hocking radiation

is a real thing? How do we know hocking radiation is a real thing? Simple answer, we don't. It's theoretical. It's predicted. It makes more sense than black holes not giving off hawking radiation because that would require them to be at absolute zero. And it would be in contradiction with lots of things we know about like entropy. You know, black holes have to have a temperature because I have to have microstates inside because they have to receive information. When something falls into a black hole, they are gathering quantum information. And in order to have that information, you have to have some entropy. And entropy means temperature.

So again, it's sort of an argument from statistical mechanics. But you're right. We haven't observed it directly. But it's opened up a really rich vein of area for people to explore. It's like giving us a crack in the facade of black holes where people can jump in and then explore more properties of black holes, but it's not something that we have confirmed experimentally. It's very, very, very faint. Really, really large black holes emit very, very, very faint hawking radiation.

It's actually the smaller black holes that emit more hawking radiation, and they would glow very brightly. And just before a black hole like evaporates into nothingness, it would be quite bright. And we've looked for that, but we haven't seen any evaporating black holes in the universe. I see. Interesting. So it's sort of theoretical. and we think it sort of glows by this Hawking radiation,

but you're saying it makes sense based on our current theories, but our current theories sort of don't necessarily work inside of a black hole or with a black hole, right? So there might still be surprises about this whole thing. Oh, absolutely. Our current theory is almost certainly wrong. And later somebody smarter, maybe one of our podcast listeners who's going to go into this field

will come along with a full-fledged theory of quantum gravity. And it might be that that theory agrees with Hawking's theory. and this concept of hawking radiation and black hole temperatures. But it might be that it doesn't and that there are surprises. And that's exactly why we go out and we look at these black holes and we study them and we take pictures because the universe is filled with surprises and is always confronting us with different stories than the ones we were telling ourselves in our head. Yeah.

So it's a hypothetical guess theory based on a theory we think we know it's wrong is what you're saying. Also known as doing our best. Well, Stephen Hawking is usually pretty right about. stuff. So these black holes glowing and emanating sort of a slow kind of heat or radiation is one way that black holes can glow, but they can also glow more dramatically, right? Like big time. Yes, they can glow very dramatically because they have very strong effects on the gas around them. The way the black holes grows that they gobble gas and stars in their vicinity. And before the things fall into them, they swirl around for a while because they have angular momentum. Just the way the earth is going around the

sun doesn't just fall straight in, things around a black hole swirl around for a while before they bump into each other and eventually fall in. And that bumping into each other is very intense because the gravity is very intense. So if you have a huge cloud of gas around a black hole, there's a lot of gravitational friction. And that heats it up and that glows. And it can create incredible sources of light. Yeah. I guess that's kind of maybe hard for people to grasp, right? Like, you know, the Earth is orbiting around the sun, but we're not sort of or we're not getting sort of shredded and rub into bright brightness. So maybe is it because black holes are so intense and the gravity around the black

holes is like super extra intense that things just get shredded even if they're just going around them? Absolutely. But the Earth does have that effect a little bit. Like the effect of the moon is to sort of squeeze the Earth a little bit and it like massages the Earth's oceans. Or if you were a moon going around Jupiter, for example, Io, why are those moons? so hot on the inside because of the gravitational squeezing from Jupiter. And so the sun is doing that

also to the Earth. So if the sun was larger and more massive and the Earth was closer to it, then those tidal forces would really heat up the center of the Earth. And so black holes are much, much more intense gravitationally. And these accretion disks are much, much closer to them. And so this gravitational sort of squeezing and tugging heats them up. It's more of a gravitational pulling, right? Like the moon is. it's not so much squeezing the water on Earth, but it's sort of like pulling on it more in one side than the other, and that's what's causing the tidal forces, right?

Yeah, gravity depends very strongly on the distance. And so the bits of the Earth that are closer to the moon get pulled on harder than the bits of the Earth that are further from the moon. And so the result is the moon is basically trying to pull the Earth apart because it's pulling on one side harder than the other side. The same with Jupiter and its moons. You can think of it like taking a piece of chewing gum and pulling on one end only, it stretches it out.

But then if that chewing gum is spinning, then you're like constantly stretching out different parts of it. So you're keeping it warm. You're like massaging it. Like a dough. Like if you need a dough, it sort of heats up a little bit, right? And now it's spinning like a pizza dough. We're a little hungry here.

I don't know if you can tell. So that's what's kind of what's happening to things around a black hole. They're getting kind of like stretched a lot by this, the intense gravitational forces. But it also sort of happens, Not just because of the tidal forces, but just because it's going so fast around the black hole, right? Because things get sucked in pretty fast. Depending on how fast a black hole is spinning and the stuff around it is spinning, absolutely.

It can get going pretty fast. Just like a figure skater speeds up and spins faster if she pulls in her arms because of conservation of angular momentum or just the way like comets as they approach the sun from the outer solar system get going really, really fast. As you fall in towards the center of the black hole, then you go forward. faster and faster, both in spin and in velocity. So you get a lot of particles moving really, really fast, bumping into each other. And that's what temperature is. Temperature is basically like speedometer of particles. Right, right. So things are crazy spinning around a black hole. And so somehow that gives off energy, right? Like things are getting pulled apart, rubbing, exploding, crashing.

And that just gives off a lot of light and radiation. Yeah, like we said before, things that are hot, they glow. And so this gas is super duper hot. And so it glows in the X-ray gives us these very, very powerful X-ray radiation, which is just another kind of photon, just much higher frequency. Yeah, pretty cool. And so for a long time, we thought that these glowing black holes were actually stars, right? I mean, in fact, we call them quasi-stars. Yeah, they've been seen since the early parts of last century.

In the 1950s, they started to study them more intensely, but they didn't really understand what they were because they were very, very bright, but their spectrum was very, very weird. Like if you look at the frequency of the light that they emitted, it didn't match what typical stars emitted. They looked like they were redshifted super duper far. Like the photons were shifted really far down in wavelength compared to most stars. And usually when that happens, it means that the thing you're looking at is really, really far away. So it's moving away from you quickly. That's how we measure the distance to things sometimes is that we measured this redshift.

But in this case, these red shifts were super dramatic and yet the objects were really bright. And so at first glance, it seems like something which is really bright and also crazy far away, which means it must be like redonculously bright. So first astronomers were really scratching their heads, wondering what these things were. Interesting. Like to the naked eye, when you look up at the night sky, it just looks like a little bright pinpoint. But when you look at the like the frequency of the light, it actually tells you that it's crazy bright and crazy far. Yeah, they can be like a hundred times brighter than the other galaxies near them.

So people are like, what's going on? how are these things so bright because they're already really, really far away. These things like just to get a scale, you know, these things like at their source would have to be like four trillion times brighter than the sun, like at the same distance. And so then it turned out that those are actually black holes, that the ones that we saw in the sky that were so bright and so far. Yeah, so people saw these before black holes were really taken seriously as an astronomical object. And so it took a few decades for people to sort of put those two puzzles together. You know, what are these quasars and also are black holes real? People put that together like, hmm, wow, black holes.

Maybe that's what these things are. Maybe they are powering these quasars. And they came all together when people started studying like the size of these quasars. One thing that's really interesting about them is that quasars are highly variable. They don't just like burn brightly all the time. That's because the gas around the black hole is really volatile. But if the brightness is varying like over a few days, that actually tells you something about the size of the object. because it means it can only be like a few light days across.

It can't be really, really large and also like coherently varying in time very quickly. And so that tells you that it's really small and also really intense. It takes a lot of mass to power all that brightness. So that's when people started to realize, hmm, maybe these things are powered by black holes. You're saying like if something is that bright

and if it's large, it wouldn't be, you know, changing in terms of the light it gives off. That's right. you can't have two things that are like a light year apart coherently varying in time, like having the same pattern over just a few days because they have to be somehow communicating with each other, but they're a light year apart, so they can't. So if two things are in sync over a period of like a day or an hour, then they have to be

within a light day or a light hour of each other if the same process is driving them. So it's like a cool, indirect way to get a sense of the size of an object by seeing how quickly it's light varies. Interesting. I guess the speed of light limits even like how fast you can coordinate different parts of a bright object. It's kind of what you're saying. Yeah. If they're driven by the same fundamental mechanism, they have the same underlying cause, like two sides of an object, grow brighter or darker because of the same underlying physics that's happening inside of it, then they can't be that far apart. So you concluded, well, this must be something super bright, super far, and also super small, or at least, you know, at least the size of like our solar system or a sun. Exactly. And another interesting piece of the puzzle is that we mostly see them really far away.

Right. We said earlier that we see them really high red shifts, which means they're mostly far away. And you might wonder like, well, if these things are really bright, shouldn't we see a bunch of them closer up that are like obviously really, really bright? But the thing is that these things were made mostly in the early part of the universe's history. Like around three billion years was the peak time to make these quasars. And since then, we haven't really been making them very much anymore. So most of the quasars in the universe are far away from us because the ones close by have already died out. They don't last that long. They only last like 10 or 20 million years.

I guess what you're saying is that, you know, not all black holes have an accretion disc or like stuff glowing brightly around them. And so the ones that do seem to have them that we can see are probably old because probably the black holes that are closer to us have already burned out their accretion disk. Yes. And it's not something that we understand very well. As we'll talk about a bit more later, like what's going on very close to the black hole, how they gather gas and how they blow that gas away due to the intense radiation is not something that's currently very well understood. We think that about 5 to 10 percent of galaxies with black holes at their core have quasars.

So a lot of the galaxies around us that have black holes don't have a quasar. It requires like sort of special conditions. Not every single one does it. Right. Or maybe they did, but it's no longer kind of burning bright. Yeah. Maybe they grew to a certain size and they've like blown away a lot of the gas that they would otherwise feed. Remember we had another episode about how you could quickly make a black hole and it's not actually that easy to just like dump a lot of stuff into a black hole because as they grow, their gravity gets stronger and they create this intense radiation, which actually works against them because it blows away a lot of the stuff nearby.

Interesting. It's like it gets indigestion. You get to you get to feed it slowly. you got to burp your black hole just right yeah otherwise don't burp other things out so then that's kind of so we don't see quasars near us meaning black holes that glow brightly but they are out there and they do it through this kind of mechanism of the accretion this burning stuff up crashing it around itself and and also sometimes that radiation can be very focused right in which case we get super bright quasars yeah if quasars happen to be pointed right at us or they're moving towards us then we call them

lasers because their radiation gets boosted by being pointed right at us. Right, but I guess this is kind of a subtle point is that sometimes in a black hole, the accretion disk is glowing, it's bright, we can see it from far away, but sometimes it's sort of aligned in the right way where it's super extra bright, right? Yeah, if it's lined up directly to Earth, like the most intense part of the Quasar mission is pointing right at the Earth, then they get super extra bright. Does that mean that all quasars or all glowing accretion disks,

are directional like they all sort of point in a particular way like a flashlight they do but not that intensely they're not like extremely focused the way like a pulsar is a pulsar you just won't even see that radiation if it's not pointed at the earth these are not as directional but if the intense part of it is pointed at the earth then yeah there's an enhancement factor there but black holes do have another way that they glow which is very pointed oh yeah what is that well on top of the accretion disk, they also sometimes create these incredible jets of matter, which fly out from the poles of the black hole, both sort of north and south. And these things are really extraordinary. So some black holes don't have an accrucian disc. Some of them do. It's glowing. It's glowing in a sort of general

direction. And some of them are even more focus is what you're saying. Like somehow this accretion disc gathers things and shoots it in one way, sort of like a tornado? Sort of like a tornado. Some of these black holes have these incredible things we call jets, which shoot out photons and other kinds of matter, really, really long jets, like much larger than the black hole itself. For example, some of these jets are like 5,000 to 100,000 light years long. Whoa. And so what do they look like? They sort of look like a spotlight shining out into the night sky, kind of. Yeah, you can see like a little dot from the quasar at the core. And then you see these incredibly long rays which shoot out into the interstellar medium.

And because they then hit stuff like gas and dust, they can create these big shockwaves. And so you can Google a picture of like astrophysical jets, but they look like these incredible fireballs shooting out both sides of the black hole. And they're much, much bigger than the actual extent of the black hole. One astronomer described as like seeing the Statue of Liberty popping out of a marble. That's a sight to see. But you're saying we don't really understand how these jets are formed, right? Like I imagine the accrucied does this stuff kind of orbiting around the black hole

waiting to fall into the black hole. So how does stuff actually kind of pop out? It's all connected into this question of how stuff falls into the black hole and what happens. But we think that a lot of black holes are not just curved regions of space time. They're also spinning. And also they probably have electric charge. And those are the three things that black holes can have, mass, spin, and charge. And if a black hole has a left.

electric charge and it's spinning, then it also has a very, very powerful magnetic field. And that magnetic field will direct the path of particles. Just the same way that the Earth's magnetic field changes how the solar wind hits the Earth. Most of those particles don't end up coming down and hitting us. They spiral around magnetic field lines and go to the North Pole or the South Pole. And that's what the northern lights are. In the same way, this incredibly intense magnetic field of a black hole, some of these particles which otherwise might have fallen into the black hole

gets sort of like funneled up and shot out the top or the bottom of the black hole. Interesting. It's sort of channeled by this magnetic field. But I guess the question is how does a black hole get a charge? Like, does it, because it absorbs more electrons than positive charges or how does it get a charge? Yeah, we think that charge is conserved in the universe. And so if you have a black hole that's neutral and you toss an electron into it, that black hole now has a charge.

And you can't, like, tell where the electron is inside the event horizon. All you can tell us that the black hole itself is now charged. And so any black hole which eats more positive than negative particles will have a positive charge. And the same is true for the opposite scenario. So somehow the black hole ate more electrons than positrons? And we do have an asymmetry in our universe, right? There are a lot more electrons out there than positrons. And stars and other matter have more electrons in them than positrons.

while there are also protons in there to balance things out, the matter, anti-matter, asymmetry of the universe means that there are a lot of these charged particles floating around for black holes to gobble up. Interesting. That's true for the whole universe. You're saying the whole universe has a negative charge? Well, that's a really fun question.

What is the charge of the whole universe? Is it positive? Is it negative? Is it an optimist? Is it a pessimist? That's a really cool question. I think that if charge has always been conserved, then the universe must have the same charge it had early on.

And so if it came from like an inflaton field or something that we've discussed recently, it probably has an overall zero charge. But in the end, those charges break up into electrons and protons and other kinds of particles, some of which might be more likely to be eaten than by black holes. But they're also just there are patches, right? The universe is not completely smooth. And so in the same way that black holes spin because there's angular momentum, even if the total spin of the universe is zero, there are patches of it that spin left or spin right.

In the same way, there are patches of the universe that have more matter or less matter. There probably are patches of the universe that have like more positive charge and more negative charge. So black holes end up accumulating some charge. Like the chances of getting exactly zero charge if you have, you know, 10 to the 50 particles is like the chances of flipping a coin 10 to the 50 times and getting exactly 50% heads. It's very unlikely. Yeah, it seems like it. So if you're a black hole, you could be team positive or team negative. There's two teams.

Exactly. Probably very few black holes like exactly balanced on that knife's edge. And as a result, they get very strong magnetic fields. Right. And so that's kind of the most intense way that a black hole can glow. Although it's technically not glowing. It's just kind of redirecting and swirling and igniting the stuff around it and then shooting it in one particular direction.

Yeah. And so these astrophysical jets are super fascinating and really a source of research right now. people trying to use them to understand what happens to a particle as it falls into a spinning, electrically charged black hole, whether it gets repelled by the magnetic field of the black hole or whether it gets sucked in, all this kind of stuff. That must be pretty cool to think about and model. All right, well, let's get into what happens if you focus one of these jets on Earth. Is it good news or bad news?

And let's talk about our most recent pictures of black holes. But 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 2, 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.

Your entire identity has been fabricated. Your beloved brother goes missing without a trace. You discover the depths of your mother's illness, the way it has echoed and reverberated throughout your life, impacting your very legacy. Hi, I'm Danny Shapiro. And these are just a few of the profound and powerful stories I'll be mining on our 12th season of Family Secrets.

With over 37 million downloads, we continue to be moved and inspired by our guests and their courageously told stories. I can't wait to share 10 powerful new episodes with you, stories of tangled up identities, concealed truths, and the way in which family secrets almost always need to be told. I hope you'll join me and my extraordinary guests for this new season of Family Secrets.

Family Secrets. Listen to Family Secrets Season 12 on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Hey, sis, what if I could promise you you never had to listen to a condescending finance, bro, tell you how to manage your money again. Welcome to Brown Ambition. This is the hard part when you pay down those credit cards. If you haven't gotten to the bottom of why you were racking up credit or turning to credit cards, you may just recreate the same problem a year from now. When you do feel like you are bleeding from these high interest rates, I would start shopping for a debt consolidation loan, starting with your local credit union, shopping around online, looking for some online lenders because they tend to have fewer fees and be more affordable. Listen, I am not here to judge. It is so expensive in these streets. I 100% can see how in just a few months you can have this much credit card debt when it weighs on you. It's really easy to just like stick your head in the sand.

It's nice and dark in the sand. Even if it's scary, it's not going to go away just because you're avoiding it, and in fact, it may get even worse. For more judgment-free money advice, listen to Brown Ambition on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. A foot washed up a shoe with some bones in it. They had no idea who it was. Most everything was burned up pretty good from the fire that not a whole lot was salvageable. These are the coldest of cold cases, but everything is about to change. Every case that is a cold case that has DNA right now in a backlog

will be identified in our lifetime. A small lab in Texas is cracking the code on DNA. Using new scientific tools, they're finding clues in evidence so tiny you might just miss it. He never thought he was going to get caught. And I just looked at my computer screen. I was just like, ah, got you.

On America's Crime Lab, we'll learn about victims and survivors. And you'll meet the team behind the scenes at Othrum. the Houston Lab that takes on the most hopeless cases to finally solve the unsolvable. Listen to America's Crime Lab on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. All right, we're talking about glowing black holes,

and this is, I guess, a pretty glowing review of black holes. Would you say that? We give black holes five stars. Absolutely. Or a million stars. Sometimes a trillion stars. Who knows? So sometimes they emit these intense jets and that's when they really shine in the sky.

But they can be sort of dangerous, right? Like if a black hole suddenly focus its jet on us, it might fry us, kind of, right? Yes. These are very intense sources of radiation. Fortunately, none of them are shined at Earth right now because they go really, really far. And the black hole at the center of our galaxy, which is like one that might be capable of creating very intense radiation, We don't think that it has any of these jets. It might have very small ones, but we're not sure.

We're going to try to take a picture of it soon. Well, it's sort of sad that black holes are getting their jet packs before humans are. But we do have sort of photos of black holes glowing. Like, it's not just something that we're positing or wondering about. We do have more recent pictures of black holes, right? And you can see them glowing. Yeah, several years ago, they tied together a bunch of radio telescopes around the world into sort of like a huge meta telescope.

And by taking data together for about 10 days, different parts of the Earth, all working together, all pointed at the same black hole, they were able to sort of tie those together into a radio telescope effectively the size of the Earth. So this is called the Event Horizon Telescope. And they took data for about 10 days and then crunched it with their computers for like two years.

And in April 2019, they put out what was called the first direct image of a black hole. And you might remember it. It looks sort of like a glowing donut. Yeah, so you can Google this and image and do an image search where, I guess, what would you search for? Black hole photo? Yeah, black hole photo, absolutely. That pops right up.

And so you can see, you can see sort of the dark circle in the middle, the glowing disc. And it's sort of skewed, though, right? It's not like a perfectly round donut. It's sort of skewed one in one direction. Yeah, it's like a crispy cream you're sort of angling in at as you're about to take your first bite. Yeah, it got kind of squished on one side. And what you're looking at there, the glow, of course, is not from the actual black hole. You're not seeing hawking radiation.

You're seeing the glow of the accretion disc. And that black hole is M87. It's at the center of a galaxy that's about 55 million light years away. But they chose it because it's incredibly powerful black hole. It's like 6.5 billion solar masses inside of it. Wow. 6.5 billion times the mass of our sun. and it's fairly close enough for us to sort of look at it.

And so we have a picture of its accretion disk, and there's sort of different theories about what's going on there. That's right. And so the first picture just sort of like gave us the first glance. And we saw the accretion disk. We saw the glow. We confirmed what we thought you see the hole in the center of it, which is the event horizon.

And that's about as big as we expected it to be. It's really incredibly huge, though. Like that event horizon is larger than the radius of Pluto. Like that black hole is a monster. Wow. Meaning like you could sit in inside of our solar system and it would basically take over the whole solar system. It would take over the whole solar system. Exactly. And recently what they've done is they've studied that data in more detail. They went back and they reanalyze that data, trying to get more information about what's swirling around inside that accretion disk.

Because what they did at first would just sort of like look at the photons and gather them and say, where is it bright? Where is it not that bright? And that's the picture that you see is like an intensity map essentially shows you where is. it's glowing hot and where it's not glowing as much. What they did now is they went back and they analyzed it to see how those photons are polarized. Like photons, when they move through space, can do so in various ways. Like we sometimes talk about how electrons have spin, spin up or spin down. Photons also have spin, so they don't just fly through space with energy. They can also spin in various ways. You might be familiar with like sunglasses that filter out polarized light, for example. And so light comes in sort of different spins. And what they did is

they looked at the photons and counted how many spin in different ways because this tells you something really interesting about the magnetic field inside that accretion disk, which affects how photons spin. Well, it's like you're looking for extra information in the light that might tell you what's going on because we don't understand it, right? Exactly. It's like you first had a black and white picture and now you're looking at the different colors, right?

You're looking for extra information, new dimensions to this. So they crunched the same picture, the same data, through their communication. for another two years, and now they have an updated photograph. And this one looks quite different because it's still the accretion disk, but you can see these stripes. You can see these like twists, this spiral pattern that tells you sort of where the magnetic field is in the accretion disk and sort of what its intensity is. Interesting. Like the whole disk has a magnetic feel or there's like variations in the field all around it? There are variations in the field.

And from the pattern of where the photons are and how they are polarized, you know, You can get a sense for the strength of the magnetic field and how those magnetic field lines look, which tells you a lot about how things must be moving inside the accretion disk because those very intense magnetic fields are sort of like funneling particles. They're telling particles where they can and can't go.

Interesting. Like you're looking at the texture of the accretion disc. Yeah. And so there are two theories about what's going on there and they have pretty fun acronyms, mad and sane. It's either a crazy black hole or a... A reasonable black hole. Reasonable black hole, yeah.

Yeah, people were wondering how this works and they developed these different models for how things in the accretion disk get sort of slurped up by the magnetic fields and then shot into this helix, which pushes them out into this astrophysical jet. Like how do particles when they fall into the accretion disk, how do they sort of miss falling into the black hole and end up pumped out into this incredibly long death array through space? So first people thought like mostly it's just sort of crazy and turbulent that you don't have really intense magnetic fields, but that. that stuff just sort of like falls into the center and the accretion disk sort of controls the helix, that its angular momentum is sort of what's driving the spinning of everything and that the helix sort of forms eventually from that spin. That was the model they called sane, stable and normal evolution, S-A-N-E. And then there was a competing model they call MAD for Magnetically Arrested Disc. This is a model for what happens if you like really crank up the magnetic fields, like really strong

powerful magnetic fields so that they're sort of in control. And what happens there is that you expect like coherent channels of particles. You expect like tubes of particle being funneled by this magnetic field really quickly wrapping up into a very powerful helix. And it also predicts more polarized light because of these strong magnetic fields. Interesting. It's like we know that there's an accretion desk, but we don't know what's kind of dominating the way it works. Is it gravity? Is it magnetic fields. And it sounds like it's mostly magnetic fields, or at least they play a huge part that we didn't think about before. Yeah. And so this updated picture that shows us the polarization of the photons, it helps us determine which of these two models is accurate. And so the data

supports that black holes are mad rather than sane, that they have really intense magnetic fields. And that's what's creating this helix. And that's what pulling the particles out of the accretion disk and then into this jet that reaches out through space. But what do you think make the mat, though, not getting enough attention. It's because they got overcharged. Nice. They stop being positive. Exactly.

About the whole thing. Exactly. You eat too many electrons and you end up feeling kind of negative. Yeah, they had a negative experience for sure. Now they're mad. They lost their sanity. There you go. Exactly.

And so it's cool because it's the first time we've really seen something about the dynamics of the accretion disc. Before we saw sort of like a static image, like, okay, it's there. It's a blob. We know the shape. that's cool. Now we're seeing sort of like how it's moving with the energy flow is inside of it, which really helps us build a picture for how the matter is flowing in and how it's getting ejected. Yeah, pretty cool. And I guess what's interesting is that we are getting these sort of, you know,

more accurate, more interesting pictures about what's going on outside of a black hole. Like we're getting closer and closer to the actual black hole itself and kind of maybe looking at what's going on in it. Yeah, we'll be pushing up harder and harder against that envelope of the event horizon. The more information we can gather about what happens very close to the black hole, the more it helps us refine our models for what's going on inside the black hole. People talk a lot about science being testable and falsifiable, right? But even if we can't ever see what's inside a black hole, we might be able to develop a pretty strong theory for what's going on based on its impacts on the outside. If we can build a theory which very accurately predicts what's going on outside black holes or predicts

what happens in areas we haven't seen yet, we could still test it outside the black hole and draw conclusions about what might be going on inside. Wow, pretty cool. And what's amazing is that we can do that from all the way out here, right? Like, we are a long distance away from this black hole. It's not like you can see it in the night sky. It's like it's hidden inside of a whole galaxy even, right? Exactly. And each galaxy itself is quite faint, right? This one is really, really far away. It's much further away than Andromeda. So it's in the night sky, it's just like a fuzzy little dot. But these radio telescopes are very powerful. And so using a huge telescope sort of like get pictures with slightly different angles, then we can figure out something

about the dynamics of what's going on at the heart of that galaxy. And we can study that galaxy better than we can study the center of our own galaxy. Right, because I guess there aren't that many stars kind of block into view. Is that what's going on? Yeah, two things are happening there. One is that the galaxy is sort of oriented in such a way that we can see its heart, whereas in the Milky Way, we're like right in the middle of it. And there's a lot of gas and dust between us and the center of our galaxy and other stars, as you say. The other thing is that this thing is a monster compared to our black hole. So it's much bigger and it's glowing very, very brightly. Whereas our black hole in the center of the Milky Way, Sagittarius A star is not as big. I mean, it's quite

impressive. But we don't think it's a quasar and they might or might not have sort of faint astrophysical jets for us to study. But we'll know soon because the same group is hoping to point their ritual event horizon telescope at the center of our galaxy and try to take a picture of Sagittarius A-Star. Well, they've been pointing at it all this time. It's just that the images from this larger black hole were sort of easier or radier sooner, right? Yeah, well, they need dedicated time on these radio telescopes, which are, of course, of interest for lots of other things like searching for intelligent life and looking for

exoplanets and whatever. So you need dedicated, coordinated time on all of these telescopes in order to gather this data. So if you've ever wondered what a black hole looks like or want to see what it looks like, just looking up on the internet, black hole photo. Although we think it's a black hole, right? We talked last time about how it could just be maybe a really a dark star or a neutron star, right? Yeah, we don't actually know. All of this information is indirect.

Most of the evidence is it's something. It's very massive. It's very small. And black hole is the only thing we think that fit the bill, though there are some folks out there coming up with other crazy ideas like dark stars, which are powered by quantum mechanics and not actually having event horizon. So maybe one day we'll just have to get closer so we can see. one of these things with our own eyes.

Yeah, it could be like a gray hole. We talked about that last time. Yeah, so another awesome reminder of how mysterious the universe is, but also how discoverable it is if we can eventually get pictures of it and maybe even figure out what's going on inside of the texture of the black hole itself. And how physics and math can really guide us to an understanding of the craziest corners of the universe so that even things like black holes and astrophysical jets can start to make sense to you and to me.

Physics and math. How would you combine those two words then? Fast? Fast, math? Mythist. Yay. You're a miscissist. That's the one.

I'm a mythicist. Yeah, you're mysticist. Are you a mystic? Is that what you're saying? I'm a mythical figure. You're a mathematical, mystical, most. On his cosmic quest for understanding the contextual clues of the cosmos. Yeah.

Well, we hope that gave you a lot to think about, and 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.

December 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. Your entire identity has been fabricated. Your beloved brother goes missing without a trace.

You discover the depths of your mother's illness. I'm Danny Shapiro, and these are just a few of the powerful stories I'll be mining on our upcoming 12th season of family secrets. We continue to be moved and inspired by our guests and their courageous. told stories. Listen to Family Secrets Season 12 on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Do we really need another podcast with a condescending finance brof trying to tell us how to spend our own money? No thank you. Instead, check out Brown Ambition. Each week, I, your host, Mandy Money, gives you real talk, real advice with a heavy dose of I feel uses, like on Fridays when I take your questions for the BAQA. Whether you're

trying to invest for your future, navigate a toxic workplace. I got you. Listen to Brown Ambition on the IHeart Radio app, Apple Podcast, or wherever you get your podcast. This is an IHeart podcast.