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Become an Explorer and seek out unforgettable places 0:01:48.400 --> 0:01:51.840 while enjoying rewards everywhere you travel. Cards issued by JP 0:01:51.920 --> 0:01:55.920 Morgan Chase Bank NA Member FDIC subject to credit approval Offer, 0:01:56.000 --> 0:01:57.800 subject to change. Terms apply. 0:02:05.840 --> 0:02:08.680 Hey, Orge, you work with a lot of scientists. Who 0:02:08.760 --> 0:02:11.079 is the brightest one you've ever interviewed? 0:02:11.240 --> 0:02:13.360 Well, I have made a lot of Nobel Prize winners. 0:02:13.600 --> 0:02:16.960 They're all pretty humble, but yeah, generally they're pretty uh 0:02:17.560 --> 0:02:20.400 sharp at that level, you know, Beams of light or 0:02:20.400 --> 0:02:22.919 shooting out of their eyes. They have an ore of genius. 0:02:24.480 --> 0:02:26.040 So do you think when you're talking to a scientists 0:02:26.040 --> 0:02:27.760 you can predict if they're going to be a future 0:02:27.800 --> 0:02:28.639 Nobel Prize winner? 0:02:28.720 --> 0:02:31.000 If I could, that would be awesome. I could probably 0:02:31.000 --> 0:02:32.640 make a lot of money that way. Aren't there betting 0:02:32.680 --> 0:02:34.400 pools for Nobel Prize winners? 0:02:36.160 --> 0:02:38.799 If there are, you probably qualify as insider information. 0:02:39.160 --> 0:02:56.280 Well, good thing, I'm not a betting person. Hi am 0:02:56.360 --> 0:02:59.280 Jorhemaker Tudas and the author of Oliver's Great Big Universe. 0:02:59.600 --> 0:03:02.120 Hi Daniel, I'm a particle physicist, a professor at you 0:03:02.120 --> 0:03:04.720 see Irvine, and I actually do have a tiny slice 0:03:04.720 --> 0:03:05.800 of a Nobel Prize. 0:03:06.040 --> 0:03:08.120 Ooh, what does that mean? Like they shaved off a 0:03:08.160 --> 0:03:09.359 piece of the metal or something. 0:03:10.840 --> 0:03:13.519 No, I'm one of a large group of collective winners 0:03:13.800 --> 0:03:14.840 of the Nobel Prize. 0:03:15.040 --> 0:03:15.359 Oh. 0:03:15.880 --> 0:03:18.280 Several years ago they gave the Nobel Peace Prize to 0:03:18.400 --> 0:03:22.400 the European Union, and that's back when Britain was a member. 0:03:22.440 --> 0:03:25.640 And I'm a citizen of the UK, so I'm not 0:03:25.639 --> 0:03:28.080 sure if i lost it during Brexit, but I was 0:03:28.200 --> 0:03:31.440 briefly one five hundred millionth of a Nobel Prize winner. 0:03:32.120 --> 0:03:34.560 Oh, I see you and all Europeans have won the 0:03:34.560 --> 0:03:38.040 Nobel Prize. Well, technically you're not a part of Europe, 0:03:38.080 --> 0:03:39.520 so yeah, I think you did lose it. 0:03:40.960 --> 0:03:43.120 I used to round that up to one Nobel Prize. 0:03:43.120 --> 0:03:44.760 Now I guess I got to round it down to zero. 0:03:45.160 --> 0:03:48.680 Zero. Yeah, I think you could have rounded it down 0:03:48.680 --> 0:03:54.600 to zero before. You know, one fortieth million probably maybe 0:03:55.440 --> 0:03:56.120 count to zero. 0:03:56.920 --> 0:03:59.280 Well to me, one five hundred millionth was pretty different 0:03:59.280 --> 0:04:00.960 from zero, but I take your point. 0:04:01.160 --> 0:04:03.520 But anyways, welcome to our podcast, Daniel and Jora Explain 0:04:03.600 --> 0:04:06.560 the Universe, a production of iHeartRadio. 0:04:06.000 --> 0:04:08.400 In which we think everybody deserves a prize for their 0:04:08.480 --> 0:04:12.920 curiosity about the universe. We're here to stimulate that curiosity, 0:04:12.960 --> 0:04:15.280 to encourage it, and to go with you on the 0:04:15.400 --> 0:04:19.840 journey of exploration of understanding the universe. We think, we hope, 0:04:19.839 --> 0:04:22.520 we believe that the universe out there can be understood 0:04:22.520 --> 0:04:25.919 and deserves to be understood, and that everything that scientists 0:04:25.960 --> 0:04:29.039 have figured out so far and that they're puzzling over 0:04:29.160 --> 0:04:31.760 currently deserves to be explained to you. 0:04:32.120 --> 0:04:35.000 That's right. We're here to illuminate the darkest corners of 0:04:35.080 --> 0:04:37.679 science and take you on a trip to the bright 0:04:37.760 --> 0:04:40.880 future of our understanding of how things work and why 0:04:40.880 --> 0:04:41.880 things are the way they are. 0:04:42.080 --> 0:04:45.200 We want to understand everything here on Earth, how water flows, 0:04:45.279 --> 0:04:48.880 how mountains form the history of life, but we also 0:04:48.920 --> 0:04:52.480 want to understand our vast cosmos, what's happening in the 0:04:52.600 --> 0:04:56.120 dark deep reaches of space. How did the universe get 0:04:56.160 --> 0:04:58.359 to look the way that it does. What are the 0:04:58.360 --> 0:05:03.640 most powerful forces on galaxies and stars and galactic clusters 0:05:03.680 --> 0:05:07.640 out there shaping the entire structure of space, time, and 0:05:07.760 --> 0:05:10.080 the universe. And to do that we have to look 0:05:10.120 --> 0:05:12.400 out into the night sky and gather messages that are 0:05:12.400 --> 0:05:14.400 coming here from the rest of the universe. 0:05:14.720 --> 0:05:17.919 Yeah, because the cosmos is vast and mostly dark, with 0:05:18.160 --> 0:05:20.679 lots of empty space, But there are some bright spots 0:05:20.720 --> 0:05:23.719 out there making the universe visible to us and giving 0:05:23.760 --> 0:05:27.560 us information about what's out there in the farthest reaches 0:05:27.680 --> 0:05:28.520 of existence. 0:05:28.760 --> 0:05:31.760 Though very few humans have actually left the surface of 0:05:31.800 --> 0:05:35.240 the Earth for significant periods of time and entered even 0:05:35.320 --> 0:05:38.719 our space neighborhood, we have a pretty good understanding of 0:05:38.720 --> 0:05:40.960 what's going on in the rest of our galaxy, the 0:05:40.960 --> 0:05:44.279 structure of galaxies beyond that, and all of that comes 0:05:44.279 --> 0:05:47.640 from gathering that information that's beamed to us from the 0:05:47.680 --> 0:05:50.960 rest of the universe. Imagine if instead the universe was 0:05:51.040 --> 0:05:54.239 totally dark, we would have no idea what was out there. 0:05:54.520 --> 0:05:57.560 We're grateful that at least some little fraction of it 0:05:57.600 --> 0:06:00.560 is shining brightly and letting us know, oh what it's 0:06:00.640 --> 0:06:00.880 up to. 0:06:01.200 --> 0:06:04.680 Yeah, there are things happening all over the universe creating light, 0:06:05.000 --> 0:06:07.680 blasting it out into the universe, but some of them 0:06:07.800 --> 0:06:10.960 are maybe a little bit stronger than others. 0:06:11.480 --> 0:06:13.960 That's right. We have a whole series of episodes about 0:06:13.960 --> 0:06:16.520 the darkest things in the universe, dark matter, and the 0:06:16.560 --> 0:06:19.680 mysteries of the missing gravity. But today in the podcast, 0:06:19.720 --> 0:06:22.040 we're going to go in exactly the opposite direction. 0:06:22.360 --> 0:06:24.560 So to On the podcast, we'll be tackling the question 0:06:29.760 --> 0:06:33.040 what was the brightest explosion ever seen? 0:06:33.560 --> 0:06:38.160 And was it that moment when Jorge finally understood particle physics? Boom, 0:06:38.200 --> 0:06:41.840 mind a blown as it happened. I'm anticipating it, man, 0:06:41.839 --> 0:06:42.680 we're building up to it. 0:06:43.920 --> 0:06:47.120 Has that even happened for you? 0:06:47.120 --> 0:06:48.680 You know, there's that old quote, if you think you 0:06:48.800 --> 0:06:51.799 understand quantum field theory, then you don't understand quantum field theory. 0:06:52.160 --> 0:06:54.200 So it's a matter of degrees, I think. 0:06:54.200 --> 0:06:57.200 Yeah, yeah, it's a dimmer setting a light bulb of 0:06:57.279 --> 0:07:00.880 quantum physics. But yeah, there are explosions happening all over 0:07:00.920 --> 0:07:03.680 the universe, and some of them are incredibly bright, and 0:07:03.720 --> 0:07:06.559 some of them are less bright. But maybe we haven't 0:07:06.720 --> 0:07:08.680 seen all of them. Maybe there are some that we 0:07:09.080 --> 0:07:10.920 have managed to see out there. 0:07:11.560 --> 0:07:15.280 Something that's wonderful about exploring the universe is being shocked 0:07:15.360 --> 0:07:18.720 by the scale of it. Learning how deep the history 0:07:18.760 --> 0:07:21.960 of time is, not thousands of years, not millions of years, 0:07:22.000 --> 0:07:26.160 but billions of years, Learning how large the universe is, 0:07:26.240 --> 0:07:29.960 how many billions of light years across stuff has spread out. 0:07:30.480 --> 0:07:34.160 These enormous scales that shock our understanding also serve to 0:07:34.200 --> 0:07:37.640 give us a better context for our existence. Turns out 0:07:37.640 --> 0:07:39.640 the Earth and the Milky Way are a tiny little 0:07:39.680 --> 0:07:42.600 speck of dust in the vast cosmos. But there are 0:07:42.600 --> 0:07:44.880 other dimensions to be shocked. In the sun you think 0:07:44.960 --> 0:07:48.320 is quite bright, it turns out the universe gets much much, 0:07:48.640 --> 0:07:49.640 much brighter than that. 0:07:50.160 --> 0:07:52.400 Yeah, the universe never sees this to make us all 0:07:52.440 --> 0:07:56.440 feel tiny and insignificant and short lived compared to the 0:07:56.520 --> 0:08:00.480 scale of the cosmos. And its existence. As you said, 0:08:00.520 --> 0:08:03.720 there are things that maybe would even shock of physicists 0:08:03.760 --> 0:08:05.200 about how bright they are. 0:08:05.680 --> 0:08:07.720 Absolutely, and today we're going to be learning about the 0:08:07.760 --> 0:08:12.080 brightest of all time what physicists called the boat the 0:08:12.120 --> 0:08:14.400 boat boat. 0:08:14.040 --> 0:08:16.160 The biggest of all time, the brightest of. 0:08:16.160 --> 0:08:18.760 All time, not the banana East of all time. 0:08:18.640 --> 0:08:18.720 The. 0:08:22.600 --> 0:08:27.840 Amazing of all time. So, as usual, we were wondering 0:08:27.840 --> 0:08:30.000 how many people out there had thought about this question 0:08:30.080 --> 0:08:33.960 about what is the brightest explosion ever seen in the universe. 0:08:34.360 --> 0:08:37.080 So Daniel went out there as usual to ask people 0:08:37.360 --> 0:08:37.880 this question. 0:08:38.360 --> 0:08:41.079 Thanks very much to everybody who plays for this segment 0:08:41.160 --> 0:08:43.199 of the podcast, and if you'd like to hear your 0:08:43.280 --> 0:08:46.000 voice for future episodes, please don't be shy. We would 0:08:46.040 --> 0:08:48.520 love to add you to our group. Write to me 0:08:48.520 --> 0:08:52.080 two questions at Danielanjorge dot com to volunteer, or send 0:08:52.080 --> 0:08:55.720 me questions, or send me ideas or pictures of your cats. Whatever. 0:08:55.800 --> 0:08:57.320 We love to hear from listeners. 0:08:57.640 --> 0:08:59.839 And today, Daniel, what are our players playing for? 0:09:01.760 --> 0:09:04.160 They're playing for the recognition of having their voice on 0:09:04.200 --> 0:09:08.720 the podcast. Their friends and relatives. 0:09:08.280 --> 0:09:11.040 Will all be jealous, They'll be brightly jealous. 0:09:12.920 --> 0:09:15.400 They're playing for the biggest banana of all time. 0:09:15.679 --> 0:09:17.240 So think about it for a second. What do you 0:09:17.280 --> 0:09:21.280 think is the brightest explosion ever seen? Here's what people 0:09:21.320 --> 0:09:21.800 had to say. 0:09:22.400 --> 0:09:27.320 I am going to say that is a supernova explosion, 0:09:28.360 --> 0:09:33.520 either that or the source of whatever gamma ray bursts are. 0:09:34.120 --> 0:09:38.040 The biggest explosion ever seen would have to be the 0:09:38.080 --> 0:09:40.440 Big Bang, although there was nobody around to see it. 0:09:40.520 --> 0:09:44.480 We can still see the cosmic microwave background radiation, so 0:09:45.240 --> 0:09:49.559 we still can see it. But that's not really bright anymore. 0:09:49.640 --> 0:09:51.560 So I don't know. 0:09:52.679 --> 0:09:55.720 You got me in a quandary here, So it's probably 0:09:55.760 --> 0:09:56.360 a supernova. 0:09:56.880 --> 0:10:00.560 I would imagine the Big Bang was pretty bright, maybe 0:10:00.640 --> 0:10:04.760 gamma ray burse but maybe something to do with merging 0:10:04.800 --> 0:10:10.680 black holes or merging neutron stars. I guess bright doesn't 0:10:10.720 --> 0:10:14.120 necessarily have to be in our visible spectrum. 0:10:14.080 --> 0:10:16.840 All right, A couple of answers. Kind of a trick 0:10:16.920 --> 0:10:19.679 answers here. The Big Bang was maybe the biggest explosion. 0:10:20.440 --> 0:10:21.280 Can't argue with that. 0:10:21.880 --> 0:10:23.719 You can't actually argue with that. I don't think of 0:10:23.760 --> 0:10:25.760 the Big Bang as an explosion. I think of it 0:10:25.800 --> 0:10:27.040 as an expansion. 0:10:27.600 --> 0:10:31.560 Oh, I see, you're gonna use grammar to disqualify their answer. 0:10:31.720 --> 0:10:36.040 I know, words meanings, words having meanings are so annoying. 0:10:36.440 --> 0:10:39.560 I know it should just all be bath right, But 0:10:39.679 --> 0:10:41.720 I mean, you do call it the Big Bang? I 0:10:41.720 --> 0:10:44.280 mean yourself are saying it's a bang. 0:10:46.679 --> 0:10:48.600 Well, you know there's that famous story about how the 0:10:48.600 --> 0:10:51.160 Big Bang was not named by anybody who actually believed 0:10:51.440 --> 0:10:54.000 in the Big Bang, but by proponents of the steady 0:10:54.040 --> 0:10:54.640 state theory. 0:10:56.240 --> 0:10:57.600 Physicis still call it the Big Bang? 0:10:57.679 --> 0:11:00.000 Right, they do still call it the Big Bang? 0:11:00.120 --> 0:11:02.720 Yes, absolutely, they don't call it the Big Stretch or 0:11:02.760 --> 0:11:03.719 the Big Expansion. 0:11:04.240 --> 0:11:06.000 I think we should call it the Big Stretch. I 0:11:06.000 --> 0:11:07.640 think that's a much better name. Yeah. 0:11:07.640 --> 0:11:11.040 Absolutely, Maybe we should amend the title of this episode 0:11:11.080 --> 0:11:14.560 to what was the biggest explosion besides the Big Bang? 0:11:18.440 --> 0:11:22.240 The brightest explosion? Though? Yeah, good question. I'm not sure 0:11:22.480 --> 0:11:24.880 how you measure the brightness of the Big Bang. 0:11:25.400 --> 0:11:27.560 Now, the way we phrased this question, what was the 0:11:27.559 --> 0:11:30.760 brightest explosion ever seen? Are we only counting the ones 0:11:30.760 --> 0:11:33.679 that we've seen or that we think happened, or is 0:11:33.720 --> 0:11:34.200 that the same? 0:11:34.360 --> 0:11:35.880 Well, we're only going to talk about the ones that 0:11:35.880 --> 0:11:40.200 we've seen. But as soon as you've seen something extraordinarily bright, 0:11:40.320 --> 0:11:43.600 it means that there's something out there capable of making 0:11:43.760 --> 0:11:47.080 very very bright explosions, and it's very unlikely you've seen 0:11:47.360 --> 0:11:51.400 the brightest one. So it's like discovering a unicorn. You figure, ooh, 0:11:51.440 --> 0:11:54.320 there are probably other unicorns in the forest, maybe even 0:11:54.400 --> 0:11:57.319 with longer horns. So we could only talk about the 0:11:57.320 --> 0:12:00.120 brightest one we've seen. That suggests that there are very 0:12:00.160 --> 0:12:02.680 likely even brighter explosions out there we haven't seen. 0:12:03.600 --> 0:12:05.560 But that's an assumption, right, I mean, there could just 0:12:05.559 --> 0:12:07.480 be one unicorn out there in the universe. 0:12:07.600 --> 0:12:10.439 Oh absolutely, it's a statistical statement. But yes, as soon 0:12:10.440 --> 0:12:13.280 as you discover one unicorn, you figure, like, well, probably 0:12:13.400 --> 0:12:15.920 had parents, maybe it had siblings. You know, there are 0:12:15.920 --> 0:12:19.079 probably other unicorns out there, but it could be the 0:12:19.120 --> 0:12:22.360 sole unicorn, you know, created by a random collection of 0:12:22.440 --> 0:12:26.520 quantum fluctuations. That's also a possibility, even if it's unlikely. 0:12:27.160 --> 0:12:29.240 It could be the unicorn of unicorn spotting. 0:12:30.360 --> 0:12:32.080 Yeah, we could sell it for a billion dollars. That 0:12:32.080 --> 0:12:35.400 should be our startup. My start idea is, give me 0:12:35.440 --> 0:12:37.600 a billion dollars, I will make you a unicorn, and 0:12:37.600 --> 0:12:38.959 then it'll be a unicorn startup. 0:12:39.040 --> 0:12:44.120 You would only make one unicorn otherwise, it's not worth much. 0:12:44.320 --> 0:12:45.920 Yeah, but if you only have one, you can set 0:12:45.960 --> 0:12:48.240 the price, right. I Mean, I'm not an economist. 0:12:47.720 --> 0:12:51.559 But I think that's how economy worries. Sure, well, that's 0:12:51.600 --> 0:12:52.120 our problem. 0:12:52.840 --> 0:12:56.360 We're selling shares in our unicorns, folks, Unicorn singular. 0:12:56.480 --> 0:12:58.600 But anyways, it's an interesting question. Well, what's the brightest 0:12:58.640 --> 0:13:02.480 explosion ever seen? And so Daniel steps through, what are 0:13:02.480 --> 0:13:05.800 some things that can cause explosions in the universe? 0:13:06.160 --> 0:13:09.120 Well, first, I think it's useful to think about brightness, Like, 0:13:09.160 --> 0:13:12.600 what do we mean by brightness? Obviously, you're very bright, 0:13:12.720 --> 0:13:15.320 All of our listeners are very bright, our children are 0:13:15.440 --> 0:13:17.800 very bright. But when we talk about brightness in an 0:13:17.880 --> 0:13:22.199 astronomical setting, what we mean is like how many photons 0:13:22.240 --> 0:13:25.439 are arriving from it to Earth. And it used to 0:13:25.480 --> 0:13:27.960 be that astronomy only really dealt with photons. We had 0:13:27.960 --> 0:13:31.360 telescopes that could see photons. We used our eyeballs. These days, though, 0:13:31.400 --> 0:13:34.960 we have other devices like particle detectors and gravitational wave 0:13:35.000 --> 0:13:40.320 detectors that can see other kinds of messengers from astronomical events. 0:13:41.280 --> 0:13:44.959 Now, would brightness and photons be the best way to 0:13:45.400 --> 0:13:48.560 measure the energy of an explosion like could there be 0:13:48.600 --> 0:13:52.800 an explosion that maybe you know, throws up part other 0:13:52.880 --> 0:13:56.079 kinds of particles more than photons or neutrinos or something 0:13:56.120 --> 0:13:58.640 like that that might have more energy but be less bright, 0:13:59.120 --> 0:14:01.560 or there's like a pretty good indication of the energy. 0:14:01.840 --> 0:14:04.840 No, different astronomical events have a different fraction their energy 0:14:04.920 --> 0:14:09.480 produced in photons, in neutrinos, or in gravitational waves. So 0:14:09.520 --> 0:14:11.720 the best way to do astronomy they call these days 0:14:11.880 --> 0:14:15.600 multi messenger astronomy, where you're looking for photons and you're 0:14:15.640 --> 0:14:18.719 looking for particles, and you're looking for gravitational waves. It's 0:14:18.760 --> 0:14:20.760 the best way to get a handle on what happened. 0:14:21.080 --> 0:14:23.720 For example, when we look at neutrons star collisions, you 0:14:23.760 --> 0:14:27.280 can sometimes see a gravitational wave and also see light 0:14:27.400 --> 0:14:31.400 from the collision. But sometimes like supernova can release huge 0:14:31.400 --> 0:14:34.880 amounts of energy just in neutrinos, because when the neutrinos 0:14:34.920 --> 0:14:38.000 are produced in the supernova, they're not reabsorbed, they just 0:14:38.080 --> 0:14:41.800 fly right out because the supernova itself, though it's super dense, 0:14:41.920 --> 0:14:46.000 is also transparent to those neutrinos, whereas photons get reabsorbed. 0:14:46.640 --> 0:14:49.400 So definitely there are things that are brighter in neutrinos 0:14:49.440 --> 0:14:52.280 than in photons, so that makes it very, very complicated. 0:14:52.440 --> 0:14:54.800 I think today, let's just focus on the photons. 0:14:55.320 --> 0:14:57.880 Okay, let's just focus on the photons, because my eyeballs 0:14:57.880 --> 0:14:59.280 can't see neutrinos yet. 0:15:00.760 --> 0:15:03.600 You'd have to have eyeballs the size of swimming pools. 0:15:04.240 --> 0:15:07.720 Oh, Daniel, that's very flattering. Thank you. You say my 0:15:07.800 --> 0:15:14.200 eyes are endless pools of of chlorinated water. Yeah, of 0:15:14.240 --> 0:15:15.880 physics detection technology. 0:15:15.960 --> 0:15:18.000 Yes, you're like an anime character with big eyes. 0:15:18.080 --> 0:15:19.120 Yeah, yeah, there you go. 0:15:19.400 --> 0:15:21.480 And the other issue with brightness is that it depends 0:15:21.480 --> 0:15:23.600 a little bit on where you are. Like you could 0:15:23.640 --> 0:15:26.320 have a really bright source, but it's really really far away, 0:15:26.640 --> 0:15:30.240 and so it appears quite dim. Like when quasars were 0:15:30.280 --> 0:15:32.920 first discovered, they were quite bright in the sky, and 0:15:32.960 --> 0:15:35.400 then we discovered, oh my gosh, they're also super dup 0:15:35.480 --> 0:15:39.160 far away, which means at their source they're extraordinarily bright. 0:15:39.920 --> 0:15:43.240 So what astronomers typically do is define brightness by how 0:15:43.280 --> 0:15:46.400 bright something would seem if you were one AU away 0:15:46.400 --> 0:15:48.320 from it, If you were like the distance the Earth 0:15:48.400 --> 0:15:51.200 is from the Sun away from that object, how bright 0:15:51.200 --> 0:15:51.640 would it be. 0:15:52.200 --> 0:15:54.520 That's what an AU is, right, It's like an Earth 0:15:54.520 --> 0:15:55.400 distance from the Sun. 0:15:55.600 --> 0:15:56.440 Yeah, exactly. 0:15:56.720 --> 0:15:59.120 All right, so step us through, like how bright are 0:15:59.160 --> 0:15:59.920 things in the night sky? 0:16:00.520 --> 0:16:03.320 Yeah, so if you define the Sun as brightness of one, 0:16:04.040 --> 0:16:05.800 then you can look at things like some of the 0:16:05.800 --> 0:16:08.840 biggest stars that are out there, Like the biggest brightest 0:16:08.840 --> 0:16:13.080 star ever discovered. It's three hundred and fifteen solar masses. 0:16:13.280 --> 0:16:16.200 It's got the amazing name of R one three six 0:16:16.280 --> 0:16:20.960 a one, and it's eight point three million times brighter 0:16:21.000 --> 0:16:24.760 than the Sun. Like if you took that star, what, Yeah, 0:16:24.920 --> 0:16:26.480 you took that star and put it in our solar 0:16:26.520 --> 0:16:29.240 system and looked up at the sky, it would be 0:16:29.280 --> 0:16:32.880 eight point three million times as intense as the Sun. 0:16:33.440 --> 0:16:36.000 Wow, you would need eight point three layers of sunblock 0:16:36.160 --> 0:16:38.240 just to walk out into the Sun. 0:16:38.720 --> 0:16:44.240 Eight point three million, Yes, it's ex million, Yes, exactly. 0:16:44.280 --> 0:16:46.720 So that's the brightest star in the universe already. That 0:16:46.800 --> 0:16:48.680 gives you a sense of like, Wow, this stuff in 0:16:48.760 --> 0:16:52.280 our neighborhood not really that bright. When we're talking about 0:16:52.280 --> 0:16:53.680 like Hall of Fame brightness. 0:16:54.160 --> 0:16:57.120 Wouldn't this star be huge or is it still a 0:16:57.120 --> 0:16:57.680 small star? 0:16:57.960 --> 0:17:00.480 No, it's very large. It's right up on the edge 0:17:00.520 --> 0:17:03.200 of the biggest star you can have around three hundred 0:17:03.240 --> 0:17:06.840 and fifteen solar masses. Because bigger stars have a higher 0:17:06.880 --> 0:17:09.960 temperature at their core, so they burn hotter and faster, 0:17:10.200 --> 0:17:13.200 they don't last very long typically, and they also produce 0:17:13.240 --> 0:17:16.920 an enormous amount of radiation which pulls the star apart. 0:17:17.160 --> 0:17:20.640 Stars are actually a delicate balance between the radiation pressure 0:17:20.680 --> 0:17:24.399 from fusion and the gravitational pressure inwards from all of 0:17:24.400 --> 0:17:27.320 that mass. So it's sort of incredible that so many 0:17:27.320 --> 0:17:30.240 stars are stable for millions and billions of years. These 0:17:30.240 --> 0:17:33.800 guys essentially tear themselves apart. Anything bigger than that can't 0:17:33.840 --> 0:17:36.480 really last very long. So this is the brightest star 0:17:36.480 --> 0:17:36.960 I ever seen. 0:17:37.160 --> 0:17:39.920 Could you even stand at one AU away from the star? 0:17:40.000 --> 0:17:41.320 Would you be inside the star? 0:17:41.760 --> 0:17:44.200 You wouldn't be inside the actual edge of the star. 0:17:44.760 --> 0:17:47.919 Its radius is like forty three times the radius of 0:17:47.960 --> 0:17:51.280 the Sun. So it's much much denser than our sun. 0:17:52.119 --> 0:17:54.360 But it's nowhere near an au for example. 0:17:55.400 --> 0:17:57.480 And why is it brighter? Is it just the more 0:17:57.600 --> 0:17:59.840 dense so there's more fusion going on. 0:18:00.640 --> 0:18:03.560 Yeah, fusion is very nonlinear, and so because you have 0:18:03.600 --> 0:18:06.480 so much more mass and it's more dense, then it's 0:18:06.560 --> 0:18:09.199 much hotter. The pressure and temperature at the core is 0:18:09.280 --> 0:18:12.359 much greater. And remember that while there's fusion happening at 0:18:12.359 --> 0:18:14.919 the core of our star, it's still pretty inefficient, Like 0:18:15.200 --> 0:18:17.680 most of the hydrogen in the star is not fusing, 0:18:17.920 --> 0:18:20.119 because fusion is a hard thing to make happen. You 0:18:20.200 --> 0:18:22.320 got these two protons, you're trying to squeeze them together. 0:18:22.880 --> 0:18:25.360 There are electromagnetic forces are trying to push them apart. 0:18:25.400 --> 0:18:27.840 Most of the time in the Sun, protons don't fuse. 0:18:28.359 --> 0:18:30.520 But the higher the temperature and the higher the pressure, 0:18:30.840 --> 0:18:34.000 the more often you do get fusion happening. And so 0:18:34.040 --> 0:18:36.160 the fusion is just much more efficient at the heart 0:18:36.160 --> 0:18:38.439 of this star, which heats the whole thing up and 0:18:38.600 --> 0:18:39.440 makes it brighter. 0:18:39.520 --> 0:18:42.399 WHOA, but you said they don't last pretty long. 0:18:42.880 --> 0:18:46.160 Yeah, these stars last for like millions of years, whereas 0:18:46.200 --> 0:18:49.479 smaller stars like hours less billions and red dwarfs can 0:18:49.560 --> 0:18:52.720 last even longer, maybe even up to trillions of years. 0:18:52.960 --> 0:18:55.240 We're not sure because the universe is kind of young 0:18:55.359 --> 0:18:58.040 compared to the expected lifetime of some of these stars. 0:18:59.200 --> 0:19:01.240 Now, is that as bright it gets out there in space? 0:19:01.520 --> 0:19:04.280 That's not even close to how bright things get. That's 0:19:04.320 --> 0:19:06.960 the brightest star we've seen. But stars are not bright 0:19:07.040 --> 0:19:10.240 compared to like the radiation emission at the hearts of galaxies. 0:19:11.040 --> 0:19:14.359 Big galaxies have big black holes at their centers, and 0:19:14.400 --> 0:19:17.720 their enormous gravity creates a lot of high temperature and 0:19:17.800 --> 0:19:21.399 high pressure in the accretion disk around the black hole. 0:19:21.920 --> 0:19:24.480 So the black hole, of course is black. Maybe this 0:19:24.640 --> 0:19:27.280 hawking radiation, but that would be very, very dim. But 0:19:27.359 --> 0:19:30.240 because it has so much gravitational energy, there's a big 0:19:30.400 --> 0:19:33.960 swirling mass of stuff around the black hole, and that 0:19:34.119 --> 0:19:36.919 is so hot it's emitting a lot of radiation. That 0:19:37.080 --> 0:19:40.520 radiation then gets guided by the magnetic field of the 0:19:40.560 --> 0:19:43.520 black hole up and down the poles, sort of the 0:19:43.560 --> 0:19:47.080 same way that like the Aurora borealis guides charged particles 0:19:47.080 --> 0:19:49.520 to the north pole and the south pole. Here, the 0:19:49.560 --> 0:19:53.400 magnetic field of the quasar creates two beams of particles 0:19:53.440 --> 0:19:55.720 when shooting up the north pole and when shooting down 0:19:55.760 --> 0:19:58.440 the south pole. And that's what a quasar is. That's 0:19:58.480 --> 0:20:01.280 also called an active galactic nucleus WHOA. 0:20:01.560 --> 0:20:05.040 So it creates a jet of particles or light for both. 0:20:05.280 --> 0:20:07.760 If you look at pictures of galaxies with jets, these 0:20:07.840 --> 0:20:10.400 jets can be enormous. They can be even much longer 0:20:10.440 --> 0:20:13.159 than the galaxy itself. The power of the hearts of 0:20:13.200 --> 0:20:16.679 these galaxies is really incredible. And there's an enormous amount 0:20:16.680 --> 0:20:19.239 of photons also emitted here because this is just like 0:20:19.480 --> 0:20:22.560 hot particles, and hot particles emit photons. 0:20:22.119 --> 0:20:24.240 Because I guess it can't guide the photons to the 0:20:24.280 --> 0:20:26.920 North pole and South poles, but it guides other particles, 0:20:26.920 --> 0:20:29.960 and in those particles are what emit the brightness the light. 0:20:30.240 --> 0:20:33.600