WEBVTT - Seriously, What Is Dark Matter? 0:00:01.120 --> 0:00:04.560 Welcome to Stuff you Should Know from how Stuff Works 0:00:04.600 --> 0:00:13.960 dot com. Hey you, welcome to the podcast. I'm Josh Clark, 0:00:14.000 --> 0:00:18.160 and there's Charles w. Chuck, Bryan, there's Jerry, and um, 0:00:18.239 --> 0:00:21.560 we're about to try some physics. Oh yeah, this is 0:00:21.560 --> 0:00:25.040 stuff you should know. We're about to try some food. Yeah, 0:00:25.120 --> 0:00:28.560 this did not break my brain like I thought it would. Yeah. 0:00:28.600 --> 0:00:32.239 I think it's a pretty surface level explanation, but like 0:00:32.280 --> 0:00:34.279 it gets the point across, and I don't see any 0:00:34.320 --> 0:00:36.519 reason for us to try to go any deeper. I 0:00:36.560 --> 0:00:39.240 think we're very quickly spin out of control, like a 0:00:39.479 --> 0:00:42.640 up down cork or something. Yeah. So dark matter is 0:00:42.640 --> 0:00:45.800 invisible glue that holds everything together the end, the end. 0:00:46.280 --> 0:00:48.239 We just don't know what it is. No, we'll get 0:00:48.240 --> 0:00:53.120 into it, but you might notice, dear listener, a new 0:00:53.200 --> 0:00:56.360 thing in your feed popping up next week next week, 0:00:56.400 --> 0:01:02.080 next Wednesday, Wednesday, Wednesday Wednesdays. We are debuting a new 0:01:02.120 --> 0:01:06.320 thing called short stuff, which is just the cutest name 0:01:06.560 --> 0:01:09.680 it is. It's stuff you should know. Short Stuff, I 0:01:09.720 --> 0:01:12.800 guess is the full name probably or not, who cares, 0:01:12.840 --> 0:01:14.760 but it's just it's a stuff you should know episode. 0:01:14.760 --> 0:01:18.440 It's you, Me and Jerry but over the years of 0:01:18.440 --> 0:01:22.200 of recording, like we've got these lists of topics we 0:01:22.200 --> 0:01:25.640 want to do, and this one, like part of the 0:01:25.680 --> 0:01:27.800 list is kept getting bigger and bigger and bigger because 0:01:28.160 --> 0:01:31.200 they're like topics out there that are really interesting, but 0:01:31.240 --> 0:01:34.440 they're just not big enough for a full episode, even 0:01:34.520 --> 0:01:37.720 with Tangent upon Tangent, And we could have, like we 0:01:37.720 --> 0:01:39.200 could have been like, well, we'll put like three of 0:01:39.240 --> 0:01:41.520 them together randomly. We thought about doing that one. It 0:01:41.560 --> 0:01:44.520 just didn't feel right. So what we did was spin 0:01:44.560 --> 0:01:48.680 off like a new podcast called short Stuff, which is 0:01:48.760 --> 0:01:52.280 just a smaller sized episode of stuff you should know. 0:01:52.680 --> 0:01:55.040 Just because the topic wasn't quite big enough to warn 0:01:55.120 --> 0:01:58.520 a full episode or a large size episode, we're doing 0:01:58.560 --> 0:02:02.360 a small size episode. Yeah, so look for like ten 0:02:02.440 --> 0:02:05.400 to fifteen minutes tops. I think we're in the wheelhouse 0:02:05.400 --> 0:02:07.920 of about twelve minutes. We seem to like magically hit 0:02:07.960 --> 0:02:10.839 twelve every time. Yeah, and it's like it's kind of fun. 0:02:10.919 --> 0:02:13.200 I think it's it's a great idea. I'm really happy 0:02:13.240 --> 0:02:15.160 with him. Yeah, same here. And I think the first 0:02:15.200 --> 0:02:17.400 four we recorded, we didn't know what we're gonna call 0:02:17.480 --> 0:02:19.560 it yet, And I don't believe we went to the 0:02:19.560 --> 0:02:21.920 trouble of going back and changing that. Are we gonna 0:02:22.000 --> 0:02:23.600 we might do that? Are we doing that? Jerry? She 0:02:23.720 --> 0:02:27.040 just shrugged. No, she said, now, she said, that sounds 0:02:27.040 --> 0:02:28.600 like a lot of work. Yeah, it would be just 0:02:28.639 --> 0:02:31.760 like us to just sort of waddle our way into 0:02:31.800 --> 0:02:34.480 this thing, and which is exactly what we did. But 0:02:34.520 --> 0:02:37.919 hopefully you guys enjoy them. It didn't cost you anything. Um, 0:02:38.000 --> 0:02:41.480 so don't complain. Actually do complain if they're way off 0:02:41.520 --> 0:02:43.520 base or they could be better. We want to hear 0:02:43.560 --> 0:02:45.320 about it. No, I think people will be like, oh, 0:02:45.360 --> 0:02:47.160 this is just like a little bite size stuff you 0:02:47.160 --> 0:02:48.760 should know. So that's exactly what it is. It's like 0:02:48.760 --> 0:02:51.520 a Snicker's miniature, but of stuff you should know. That's right, 0:02:51.880 --> 0:02:54.520 And you know our love of small things here, especially 0:02:54.560 --> 0:02:57.200 Snickers or like tiny Tabasco bottles. This is the tiny 0:02:57.200 --> 0:03:01.040 Tabasco bottle version of over show. Those things are priceless, 0:03:01.080 --> 0:03:06.640 all right, So physics dark matter go, let's do this, 0:03:06.760 --> 0:03:09.440 all right? So this wasn't as hard as I thought. No, 0:03:10.440 --> 0:03:13.400 and it's actually pretty easy to get across. Here's the thing. 0:03:14.400 --> 0:03:17.000 So astronomers have gotten to the point it's starting in 0:03:17.000 --> 0:03:25.120 about on astronomers and physicists and astrophysicists and even particle 0:03:25.160 --> 0:03:28.079 physicists guys to the point where all of their combined 0:03:28.080 --> 0:03:32.480 knowledge was refined enough that they could look out into 0:03:32.480 --> 0:03:34.800 the universe and be like, we can figure out how 0:03:34.880 --> 0:03:37.960 much this ways, to put it more scientifically, we can 0:03:37.960 --> 0:03:40.200 figure out what the mass of the universe is. It's 0:03:40.240 --> 0:03:42.240 going to take us a really long time, but we 0:03:42.280 --> 0:03:45.080 are now at the point where our level of observation 0:03:45.560 --> 0:03:49.280 and our level of understanding of physics is such that 0:03:49.400 --> 0:03:53.440 we can do it. We're there now. Yeah, And it's 0:03:53.440 --> 0:03:56.240 not just like, oh, well that weighs this the end, 0:03:56.840 --> 0:03:59.680 Like knowing something's mass tells you a lot about it, 0:04:00.040 --> 0:04:03.080 the way it behaves and the nature and future of 0:04:03.120 --> 0:04:05.360 the universes we'll see, yeah for sure. So it's not 0:04:05.440 --> 0:04:08.440 just weight, it's it's more complicated than that, and what 0:04:08.520 --> 0:04:10.960 weight can tell us, right. The problem is that you 0:04:11.000 --> 0:04:14.000 can't just like put a galaxy or star or something 0:04:14.040 --> 0:04:18.080 on the scale. They have to broke the scale pretty quick. Uh, 0:04:18.120 --> 0:04:22.840 it actually vaporized it. But the the there are ways 0:04:22.880 --> 0:04:26.160 you can infer the mass of something. Yeah. Um. One 0:04:26.160 --> 0:04:27.760 of the ways that you can infer the mass of 0:04:27.760 --> 0:04:30.800 a star from what I understand is to measure it's luminosity, 0:04:30.839 --> 0:04:33.160 how bright it is. Yeah, I've also heard that's a 0:04:33.240 --> 0:04:39.320 mixed bag because they have different um different sizes in 0:04:39.360 --> 0:04:44.400 their lifespan. Um, I've just heard luminosity and mass is 0:04:44.440 --> 0:04:48.680 not is not just straightforward like like most things in 0:04:48.720 --> 0:04:53.440 astro physics are. Yeah, that's the word on the street right. So. Um. 0:04:53.520 --> 0:04:55.680 When they started getting to the point where where they 0:04:55.680 --> 0:04:57.880 could infer the weight of a star, or of a 0:04:57.920 --> 0:05:01.040 galaxy or of a galaxy cluster, which is basically like 0:05:01.120 --> 0:05:05.359 a galaxy of galaxies, they started to notice something really weird. 0:05:05.720 --> 0:05:09.000 All of the matter that they could see, the stars, 0:05:09.120 --> 0:05:14.279 the gas clouds, the cosmic dust, the everything, matter, things 0:05:14.320 --> 0:05:18.039 that make up you and me, things that everything has 0:05:18.279 --> 0:05:21.400 a common basic unit and atom that's made up of 0:05:21.440 --> 0:05:25.719 elementary particles like protons and neutrons and electrons. Matter, Every 0:05:25.880 --> 0:05:30.080 non living and living thing on in the galaxy you 0:05:30.080 --> 0:05:33.279 would think is made of matter. The problem is is 0:05:33.320 --> 0:05:37.160 they started finding that, you know, this galaxy over here, 0:05:37.160 --> 0:05:41.679 in this galaxy cluster and everywhere we're looking, the amount 0:05:41.720 --> 0:05:45.400 of matter that we're seeing is way too small for 0:05:45.480 --> 0:05:48.160 the amount of mass that the thing we're looking at 0:05:48.240 --> 0:05:53.200 appears to have and a cosmological mystery was launched. What 0:05:53.279 --> 0:05:56.839 the heck is going on? Was the question of the day. Yeah, 0:05:57.000 --> 0:05:59.640 so all that matter that we know about, they call 0:05:59.760 --> 0:06:03.120 that barrionic matter. Uh. And they were like this, the 0:06:03.440 --> 0:06:06.200 calculations are off or something like, there's got to be 0:06:06.240 --> 0:06:09.359 something else there to account for this. Well, that's the 0:06:09.400 --> 0:06:14.200 to the two possibilities. Well. Uh, and so way back 0:06:14.520 --> 0:06:19.600 in uh geez was at nineteen thirty two an astronomer, 0:06:20.080 --> 0:06:25.279 a Dutch astronomer named Jan hendrik Ert because he's Dutch, 0:06:27.040 --> 0:06:30.040 he actually I believe was the first person to use 0:06:30.040 --> 0:06:32.200 the term dark matter. Is that right? That's what I saw? 0:06:32.720 --> 0:06:36.279 So dark matter is a is a sort of a 0:06:36.320 --> 0:06:40.120 placeholder name for what they came up with for this, 0:06:41.200 --> 0:06:45.320 for lack of a better word, this invisible uh matter 0:06:45.839 --> 0:06:48.240 that has to be out there is it's sort of 0:06:48.240 --> 0:06:51.279 like wind, Like you can't see wind, but that doesn't 0:06:51.279 --> 0:06:53.159 mean it's not out there because you can measure it 0:06:53.160 --> 0:06:55.760 in different ways, see how it reacts on other things. 0:06:56.600 --> 0:06:59.520 And so they called started calling it dark matter. This 0:06:59.640 --> 0:07:02.600 in sable. Well we'll talk about what it ends up 0:07:02.640 --> 0:07:04.200 sort of looking like in a minute. I want give 0:07:04.200 --> 0:07:08.280 that away yet. But this invisible matter that they think 0:07:08.600 --> 0:07:12.800 is there, right, but it doesn't. It doesn't emit or 0:07:13.000 --> 0:07:19.480 absorb light or electromagnetic magnetic energy. So it's it's way different. 0:07:19.520 --> 0:07:23.560 It behaves differently such that people were very confused as 0:07:23.600 --> 0:07:26.840 to what the heck was going on, and they still are. Yeah. Sure, 0:07:27.040 --> 0:07:29.560 So there's so this term dark matter, like you said, 0:07:29.600 --> 0:07:33.200 it's a placeholder, and it's a placeholder for the current 0:07:33.280 --> 0:07:35.760 point we are in our understanding of the universe, which 0:07:35.800 --> 0:07:40.160 is when we look out at galaxy clusters and galaxies 0:07:40.200 --> 0:07:43.240 and all this stuff, there's not enough matter to account 0:07:43.280 --> 0:07:46.120 for the amount of mass that we're seeing. So again, 0:07:46.160 --> 0:07:48.920 that means one of two things. Either there's something there 0:07:48.960 --> 0:07:54.000 that we can't detect, or our our understanding of physics 0:07:54.080 --> 0:07:56.720 is off, and the term dark matter stands for both 0:07:56.720 --> 0:07:59.400 of those. It could be a thing, an underscovered particle 0:07:59.520 --> 0:08:04.160 or something like that, or it could be a misunderstanding 0:08:04.160 --> 0:08:07.160 of physics that we need to eventually correct. Either way, 0:08:07.200 --> 0:08:11.320 there's a lot of mass that is unaccounted for throughout 0:08:11.360 --> 0:08:15.000 the universe, and it seems like there's a lot more 0:08:15.520 --> 0:08:19.080 what we call dark matter then there's regular matter. And 0:08:19.120 --> 0:08:21.400 the more we look into it, the more it seems 0:08:21.440 --> 0:08:25.119 like there's something there that we haven't discovered yet. Yeah. 0:08:25.160 --> 0:08:27.440 So right now, barrionic matter, all the stuff that we 0:08:27.520 --> 0:08:33.840 know about counts for about four and a half percent. Uh, 0:08:34.880 --> 0:08:37.480 where they peg dark matter. Then we have something that 0:08:37.559 --> 0:08:39.000 I don't even know if I ever want to cover, 0:08:39.080 --> 0:08:42.840 called dark energy, which makes up the other SEV. But 0:08:42.920 --> 0:08:45.840 they know it's there because there's something out there that 0:08:45.920 --> 0:08:51.240 we can account for that has a significant gravitational force. Right, 0:08:51.320 --> 0:08:53.800 that's where the whole the whole thing started where they 0:08:53.800 --> 0:08:57.440 first detected it. Right, so, um, when they first started 0:08:57.440 --> 0:09:00.480 looking out at galaxies and stuff like that. There's this 0:09:00.520 --> 0:09:03.880 whole thing that Newton came up with the second law 0:09:03.920 --> 0:09:06.920 of motion where and this is like a tried and 0:09:07.000 --> 0:09:10.520 true law. It's a law. This isn't Newton's suggestion of 0:09:10.640 --> 0:09:14.480 motion or Newton's second what about this of motion? It's 0:09:14.520 --> 0:09:19.400 a scientific law. That's how that's has proven and accepted 0:09:19.679 --> 0:09:21.920 as a scientific observation can be is to be made 0:09:21.920 --> 0:09:25.120 a law. And it said that when you're looking at 0:09:25.120 --> 0:09:30.120 a galaxy far far away, and the most of the 0:09:30.200 --> 0:09:33.520 matter is accumulated towards the center of the galaxy, then 0:09:33.559 --> 0:09:38.480 that means most of the mass is accumulated towards the center. Okay, yes, okay, 0:09:38.520 --> 0:09:41.880 So that means that the stars near the center are 0:09:41.920 --> 0:09:45.800 going to spin. They're going to rotate around the galaxy 0:09:46.040 --> 0:09:49.720 a lot faster than the ones on the fringes, because 0:09:49.800 --> 0:09:51.800 the ones on the fringes are going to go a 0:09:51.840 --> 0:09:54.560 lot more slowly because they're further away from that center 0:09:54.559 --> 0:09:58.560 of mass. So the gravitational pull is going to be weaker. Yeah, 0:09:58.600 --> 0:10:00.760 I mean, that's the easy ist way to say it 0:10:00.800 --> 0:10:03.760 is in the center, you have more mass. More mass 0:10:03.960 --> 0:10:08.120 means things are spinning faster, there's more gravitational pull. So 0:10:08.200 --> 0:10:11.360 all the astronomers supposed, like you said, the stuff on 0:10:11.400 --> 0:10:15.280 the outskirts are probably hanging out there spinning a lot slower, right. Well, 0:10:15.320 --> 0:10:18.079 when they looked, they found that's not the case at all. 0:10:18.440 --> 0:10:20.920 As a matter of fact, the stars on the outside 0:10:20.920 --> 0:10:23.839 are spinning around the center of the galaxy just as 0:10:23.880 --> 0:10:26.640 fast as the stars near the center of the galaxy, 0:10:26.920 --> 0:10:30.440 which makes zero sense. Yeah, it's almost as if there's 0:10:30.440 --> 0:10:33.440 some invisible force out there, right Like if you look 0:10:33.480 --> 0:10:36.560 at this, if you look at this um this galaxy. 0:10:36.600 --> 0:10:38.720 The situation that they started to find and it wasn't 0:10:38.760 --> 0:10:41.120 just one galaxy. They found it in this galaxy too, 0:10:41.160 --> 0:10:44.319 in this galaxy too, and even stranger than that, they 0:10:44.320 --> 0:10:48.160 found it in those clusters, those galactic clusters. So rather 0:10:48.240 --> 0:10:51.160 than stars that make up a galaxy, this is galaxies 0:10:51.240 --> 0:10:54.880 making up a huge, giant mega galaxy. The same thing 0:10:54.920 --> 0:10:57.520 happened the galaxies on the outer edge of the cluster. 0:10:58.000 --> 0:11:02.720 We're circling just as fast as the ones towards the center, 0:11:03.280 --> 0:11:05.559 and it just must have knocked their socks off. I 0:11:05.600 --> 0:11:08.600 can't imagine how many times they went over the same 0:11:08.679 --> 0:11:11.280 thing to make sure that they had gotten it. This 0:11:11.360 --> 0:11:15.280 is for uh clarity. This was the nineteen fifties and 0:11:15.360 --> 0:11:20.760 nineteen sixties when the yeah, okay, so what they figured 0:11:20.800 --> 0:11:23.439 out was that either there was something really wrong or 0:11:23.480 --> 0:11:25.800 there was something that they hadn't picked up yet. Because 0:11:25.840 --> 0:11:28.880 those stars on the outer edges of the galaxy, or 0:11:28.880 --> 0:11:31.880 those galaxies on the outer edges of the cluster, for 0:11:31.960 --> 0:11:35.200 as fast as they were flying they should have spun 0:11:35.240 --> 0:11:39.679 off into space. There was something missing that explained what 0:11:39.800 --> 0:11:44.320 was holding that galaxy or that cluster together as fast 0:11:44.360 --> 0:11:46.960 as the stars of the galaxies were spinning around on 0:11:47.000 --> 0:11:50.800 the outside. That was the first clue that something was 0:11:51.520 --> 0:11:56.280 way up with that, that that that astronomy was missing 0:11:56.320 --> 0:11:59.319 something big, right, And they knew this was off because 0:11:59.360 --> 0:12:02.880 they had been using luminosity, like you said, to take 0:12:02.960 --> 0:12:06.760 measurements for years and it was pretty good. But then 0:12:06.800 --> 0:12:11.440 when they started, uh, measuring the rotational velocity of things, 0:12:11.440 --> 0:12:14.640 like how fast something was spinning in relation to where 0:12:14.679 --> 0:12:18.480 it was like towards the center, it, like you said, 0:12:18.520 --> 0:12:21.600 there was a missing ingredient there that didn't match whatever 0:12:21.640 --> 0:12:24.680 these luminosity readings were showing. So you're right, luminosity was 0:12:24.840 --> 0:12:30.240 clue one. The um angular rotation was or acceleration of 0:12:30.280 --> 0:12:33.000 the outer stars was clue number two. So now we've 0:12:33.040 --> 0:12:36.760 got to two different ways of measuring the mass and 0:12:36.800 --> 0:12:41.160 gravity of remote bodies in the universe, and they don't 0:12:41.160 --> 0:12:43.959 align our point. Well, they're they're aligning in that there's 0:12:44.000 --> 0:12:47.679 something missing here um. And I think that's a pretty 0:12:47.679 --> 0:12:50.319 good cliffhanger for a breakdown too. I think people are 0:12:50.320 --> 0:12:53.599 going to be like, what, Yeah, well, why don't you 0:12:53.640 --> 0:12:56.480 guys go listen to the first half of this podcast 0:12:56.520 --> 0:12:59.000 or first part again and we'll see you after these messages. 0:13:26.000 --> 0:13:30.280 I really hope we're putting this like well, I feel 0:13:30.320 --> 0:13:33.360 like we are, but sometimes you know, you just can't tell. Now, 0:13:33.400 --> 0:13:37.280 this isn't the sun re ducks. Oh god, no, no, no, 0:13:37.559 --> 0:13:41.199 this is much more simple. So, uh, like you said, 0:13:41.440 --> 0:13:45.240 they not only studied regular galaxies, but they started to 0:13:45.320 --> 0:13:48.640 study what what you referred to as and you didn't 0:13:48.640 --> 0:13:52.920 make it up, but galactic clusters. These knots of galaxies 0:13:52.920 --> 0:13:56.840 could be thousands of them, could be hundreds of them, 0:13:56.880 --> 0:13:59.360 but they were bound together by gravity. And they were like, 0:13:59.400 --> 0:14:01.480 you know what, let's study these because maybe what we 0:14:01.520 --> 0:14:04.680 can find or you know, this is what we suppose 0:14:04.760 --> 0:14:07.080 at least, is there might be be these big giant 0:14:07.080 --> 0:14:10.120 pools of hot gas that we never could detect before 0:14:10.559 --> 0:14:13.120 and that would account for all of this mass. And 0:14:13.160 --> 0:14:17.720 they did find these superheated gas clouds and we're like, great, 0:14:18.240 --> 0:14:21.400 that's it. But they're like, it still doesn't account for everything. 0:14:21.480 --> 0:14:25.480 That's like a small percentage of of the of what's 0:14:25.640 --> 0:14:29.240 what is needs to be accounted for. Right, So it 0:14:29.320 --> 0:14:32.040 was a it was a breakthrough, but it wasn't the 0:14:32.720 --> 0:14:35.480 solution solver that they were looking for. It was because 0:14:35.480 --> 0:14:39.360 so if you can find, um, you know, something that 0:14:39.440 --> 0:14:44.240 we know has mass, like huge clouds of gas. That again, 0:14:44.280 --> 0:14:46.360 you know, particle has mass, and if you put enough 0:14:46.400 --> 0:14:48.800 particles together, it has a lot of mass. If you 0:14:48.800 --> 0:14:52.840 could fill in the blanks of the missing matter, um, 0:14:52.920 --> 0:14:56.640 that explains the mass of this thing you're looking at, great, 0:14:57.120 --> 0:15:00.000 especially if it's something we already know about, like hot gas. 0:15:00.040 --> 0:15:01.920 And they did find some hot guests. But say that 0:15:01.920 --> 0:15:07.280 that explained five of the missing of the missing mass. 0:15:07.600 --> 0:15:11.480 It didn't explain everything. And what that did do also was, Okay, 0:15:11.680 --> 0:15:15.040 we've gotten that much more sophisticated and it still hasn't 0:15:15.040 --> 0:15:18.160 answered this dark matter thing. It's pointing to the idea 0:15:18.240 --> 0:15:22.080 that there's something we haven't discovered yet that is accounting 0:15:22.120 --> 0:15:24.640 for all of this. It's very foreboding, it is, but 0:15:24.680 --> 0:15:27.640 it's also I think very exciting. Sure yeah, yeah for them, 0:15:28.200 --> 0:15:31.240 uh and us. So the other thing that happened when 0:15:31.240 --> 0:15:34.240 they started studying these galactic clusters was that they found 0:15:34.280 --> 0:15:38.000 out that these clusters and superclusters can and this is 0:15:38.040 --> 0:15:39.800 really neat. You can look up images of this. It 0:15:39.840 --> 0:15:43.760 can distort space time because their mass is so great. 0:15:44.520 --> 0:15:48.560 So if you're on planet Earth, uh, and there is 0:15:48.560 --> 0:15:51.600 a light so you're looking from like a telescope on Earth, 0:15:52.320 --> 0:15:55.080 you're looking at a distant light, like who knows how 0:15:55.120 --> 0:15:58.080 far away, like a star three billion light years away? 0:15:58.360 --> 0:16:01.880 Sounds great. In between mean you and that is a 0:16:01.920 --> 0:16:04.920 galactic cluster. Let's say that will just that will act 0:16:04.960 --> 0:16:07.960 as a lens, and depending on where it's situated to 0:16:08.000 --> 0:16:11.040 where you are relative on Earth, it will distort that 0:16:11.160 --> 0:16:15.280 light uh into one of several things. If you're in 0:16:15.360 --> 0:16:18.440 perfect alignment in it, uh, it's gonna form what's known 0:16:18.480 --> 0:16:20.680 as an Einstein ring. And if you look it up 0:16:20.680 --> 0:16:23.840 on the internet, it's like this beautiful like circle of light. Yeah, 0:16:23.880 --> 0:16:27.400 it's really cool looking. Uh. It could be elliptical or oblong. 0:16:27.520 --> 0:16:30.360 They call it the Einstein cross basically splits it into 0:16:30.360 --> 0:16:33.280 four so it just looks like four little stars, all 0:16:33.400 --> 0:16:37.160 like perfectly lined four copies of the same image. Yeah, yeah, 0:16:37.240 --> 0:16:40.360 and like a cross, yeah, perfect cross. Or it could 0:16:40.360 --> 0:16:43.080 be a cluster. And this one is sort of cool 0:16:43.160 --> 0:16:45.360 just because it's like kind of scattered. It looks like 0:16:45.400 --> 0:16:49.760 a bunch of like arcs and banana shaped arcs and arklets. 0:16:49.920 --> 0:16:52.480 But it's all different versions of the same image that 0:16:52.560 --> 0:16:54.960 we're seeing. And what you're seeing is that far away star, 0:16:55.360 --> 0:16:58.120 but you're seeing it through that galaxy cluster that is 0:16:58.160 --> 0:17:02.840 a distortion of spacetime that the the mass of these 0:17:02.960 --> 0:17:07.280 clusters are so big and so huge that the gravity 0:17:07.359 --> 0:17:12.800 in them bends light, just like a mound of glass 0:17:12.840 --> 0:17:17.560 can bend light. Same thing. Now we've gotten to the 0:17:17.560 --> 0:17:20.040 point where we are so good at math and physics 0:17:20.440 --> 0:17:23.680 that we can look at that reflection that bend and 0:17:23.800 --> 0:17:27.879 say this, this galaxy has that much gravity, and since 0:17:27.960 --> 0:17:32.080 this galaxy um has this much gravity, it must have 0:17:32.200 --> 0:17:36.000 this much mass. Now if you take that number, this 0:17:36.160 --> 0:17:41.320 much mass, and you examine the luminosity of the galaxy, yeah, 0:17:41.400 --> 0:17:44.239 you're like, this is like not off by you know, 0:17:44.600 --> 0:17:47.160 like the luminosity is ten, but the mass is ten 0:17:47.200 --> 0:17:51.840 and a half. There's like factors sometimes factors of of 0:17:52.160 --> 0:17:55.879 like times a hundred. Sometimes like there's just no way 0:17:55.920 --> 0:17:59.639 that your math is off. It's it's there's a huge discrepancy. 0:18:00.040 --> 0:18:03.360 So there's a third clue that there's something missing. Yeah, 0:18:03.400 --> 0:18:07.080 I mean that's basically all these are are little hints 0:18:07.119 --> 0:18:10.680 along the way that we're still not able to account 0:18:10.720 --> 0:18:13.480 for something with our calculation. Yeah, and rather than the 0:18:13.640 --> 0:18:18.600 better and more sophisticated our observations and exploration of space 0:18:18.640 --> 0:18:23.560 in the universe becomes it doesn't become like this. This 0:18:23.640 --> 0:18:26.320 blank is not getting filled in. It's just becoming clear 0:18:26.400 --> 0:18:29.600 and clear that that blank is there. Yeah, exactly, there's 0:18:29.640 --> 0:18:34.119 a void in either our understanding or our discovery. So 0:18:34.240 --> 0:18:38.600 then computers started getting better and better and more advanced. 0:18:38.640 --> 0:18:41.320 I love how this, uh this article puts it. They 0:18:41.400 --> 0:18:45.000 turned to the computer. It sounds like they turned to 0:18:45.040 --> 0:18:49.000 the bottle or something to compute. Uh. So computer started 0:18:49.000 --> 0:18:51.960 getting so good, and our knowledge of what was out 0:18:51.960 --> 0:18:54.199 there and our measurements of matter and mass was so 0:18:54.240 --> 0:18:57.480 great that we could take a pretty good guess on 0:18:57.520 --> 0:19:00.639 how much baryonic matter there was out there, maybe how 0:19:00.720 --> 0:19:03.919 much dark matter there might be. Design a program and 0:19:03.960 --> 0:19:07.119 a model that you could feed this information into to 0:19:07.280 --> 0:19:12.360 spit out what it might quote look like end quote. Yeah. 0:19:12.400 --> 0:19:14.760 They basically said, this is how much barionic matter we 0:19:14.800 --> 0:19:16.520 think there's. This is how much dark matter we think 0:19:16.520 --> 0:19:20.520 there is. Go computer, and they hit start on the 0:19:20.560 --> 0:19:26.520 Whopper machine, and it spit out what was sort of 0:19:26.560 --> 0:19:30.240 like a It turns out that it wasn't on the edges. 0:19:30.359 --> 0:19:34.240 It was everywhere. It was like a web that wound 0:19:34.320 --> 0:19:38.479 through everything invisible to us. That sort of acted like 0:19:38.560 --> 0:19:43.200 this cosmic glue. Yeah, and so in some places it clumped. 0:19:43.600 --> 0:19:46.200 In other places there were long filaments and it kind 0:19:46.200 --> 0:19:50.000 of looked like it had galaxies or galactic clusters trapped 0:19:50.000 --> 0:19:53.159 in a spider's web. But it just permeated everywhere. And 0:19:53.160 --> 0:19:55.200 like you said, it seemed to be like this cosmic 0:19:55.240 --> 0:19:59.840 glue or cosmic connective tissue um, and it was pretty 0:19:59.840 --> 0:20:02.000 so prizing. So they said, okay, well that's that's the 0:20:02.000 --> 0:20:06.360 computers take see if we can replicate that. And that 0:20:06.520 --> 0:20:09.560 kicked off a series of projects that are still going 0:20:09.600 --> 0:20:14.880 on today to map dark matter in the universe, which 0:20:14.920 --> 0:20:18.199 I want everybody to stop for a second, because this 0:20:18.280 --> 0:20:21.200 is about as nuts as it gets. They have gotten 0:20:21.240 --> 0:20:26.800 to the level of sophistication where astrophysicists are mapping in 0:20:27.000 --> 0:20:32.680 three D models stuff that isn't there. They're mapping three 0:20:32.760 --> 0:20:39.639 D models avoids based on how how much light bends 0:20:40.000 --> 0:20:46.880 around a galaxy three billion miles light years away light 0:20:47.000 --> 0:20:50.879 years right, and then using that to infer the gravity 0:20:51.119 --> 0:20:54.240 and then the mass, and then they're using that information 0:20:54.280 --> 0:20:57.640 to create a three D map of something that may 0:20:57.680 --> 0:20:59.879 not exist. And the coolest thing about all this to 0:21:00.080 --> 0:21:03.919 me is it's based on stuff that Isaac Newton and 0:21:04.119 --> 0:21:09.240 Einstein came up with, and well, well we won't spoil it, 0:21:09.280 --> 0:21:12.080 but they weren't wrong. But that is nuts. This is 0:21:12.119 --> 0:21:17.040 either either physics has gone totally insane, yeah, or this 0:21:17.080 --> 0:21:21.359 is the pinnacle of human ingenuity. Thus far, well, thus 0:21:21.359 --> 0:21:23.960 far for sure. I'm glad you added that. So let's 0:21:23.960 --> 0:21:26.280 talk about a couple of these. About seven years ago, 0:21:26.320 --> 0:21:28.399 in two thousand and eleven, there were a couple of 0:21:28.440 --> 0:21:34.480 teams using data from uh Schandra's X ray observatory. And 0:21:34.920 --> 0:21:36.639 what they're trying to do here, like you said, is 0:21:36.720 --> 0:21:40.879 take these create this real map based on direct observation 0:21:40.920 --> 0:21:44.680 instead of this speculative computer map. What they found out 0:21:44.760 --> 0:21:48.320 is the computer map was pretty on, which was great, um, 0:21:48.359 --> 0:21:52.280 but they needed the real things. So they are looking 0:21:52.280 --> 0:21:54.800 at a cluster or have been called a bell three 0:21:55.119 --> 0:21:59.200 three two point three billion light years from Earth, and 0:22:00.040 --> 0:22:02.240 what they saw was what looks like sort of a 0:22:02.280 --> 0:22:05.439 football and American football, we're a n Ausi football for 0:22:05.480 --> 0:22:07.760 that matter. Are they similar? I just got one in 0:22:07.800 --> 0:22:11.600 the mail. I bought one. You need to get Simon 0:22:11.640 --> 0:22:14.640 to sign it, go Melbourne. I should, but it would 0:22:14.680 --> 0:22:16.360 coust so much to ship it there and back maybe 0:22:16.400 --> 0:22:19.640 able to see Simon again one day. Is Melbourne your team? Now? Yeah, 0:22:19.680 --> 0:22:22.600 that's what I got on. That's that's a good city. Yeah. 0:22:22.840 --> 0:22:26.320 I like it so. Uh it looks like a football 0:22:27.160 --> 0:22:30.560 with one end pointing towards us or you know, we're 0:22:30.600 --> 0:22:33.000 we're on Earth, so we're the observer in this case. 0:22:33.880 --> 0:22:37.960 And uh they Here's the one thing they didn't agree 0:22:37.960 --> 0:22:40.960 on though, was the density of the dark matter on 0:22:41.040 --> 0:22:44.480 able three in the center. Yeah, which is weird because 0:22:44.520 --> 0:22:46.760 some people calculated it was more dense in the center 0:22:47.320 --> 0:22:50.680 and matter increase, and other people said it was the opposite, 0:22:50.720 --> 0:22:52.320 not like, well, we're not sure, but they thought it 0:22:52.400 --> 0:22:55.320 was uh less dark matter at the center, which is 0:22:55.359 --> 0:22:57.400 a big deal. But they yes, but they both came 0:22:57.480 --> 0:23:00.720 up with virtually the same shape and same orientation. Yeah, 0:23:00.840 --> 0:23:05.159 separately and independently, which showed we're onto something or else. Again, 0:23:05.520 --> 0:23:09.359 we're all collectively out of our minds based on some 0:23:09.480 --> 0:23:13.240 shared delusion that we're all working under. Right. Then there 0:23:13.320 --> 0:23:15.760 was another one. This one is super cool. Uh in 0:23:15.880 --> 0:23:19.840 January two thousand twelve. Uh, anytime I see international team 0:23:19.840 --> 0:23:24.320 of researchers, I get excited. But the Canada, France Hawaii 0:23:24.320 --> 0:23:28.639 telescope has a three forty megapixel camera, so you can 0:23:28.680 --> 0:23:33.040 actually take pictures of stuff that far away. It's like 0:23:33.080 --> 0:23:39.320 the iPhone Excess camera. Is that one of the new ones? Yeah? Okay, 0:23:39.800 --> 0:23:42.720 is it good. I think it's pretty good camera. It's 0:23:42.720 --> 0:23:45.840 not three forty megapixel. No, it's not. I have to 0:23:45.880 --> 0:23:48.880 say I've been to this observatory before. Oh really, it's 0:23:48.920 --> 0:23:52.080 really cool. Did you look at like the photos on 0:23:52.119 --> 0:23:54.399