WEBVTT - How Galaxies Work 0:00:01.120 --> 0:00:04.560 Welcome to Stuff you Should Know from how Stuff Works 0:00:04.600 --> 0:00:13.920 dot com. Hey, and welcome to the podcast. I'm Josh Clark, 0:00:13.960 --> 0:00:17.239 and there's Star Child Chuck Bryant, and there's Moon Rock 0:00:17.400 --> 0:00:20.720 Jerry Roland over there, and I'm just playing all Josh Clark. 0:00:20.800 --> 0:00:25.040 Like I said, but this is the Galactic Federation of 0:00:25.079 --> 0:00:29.400 Stuff you Should Know Episode of all Time. There was 0:00:29.440 --> 0:00:32.720 my all boy. Yeah, there you go. Chucklates to get 0:00:32.880 --> 0:00:36.400 nice and loaded when he talks about space stuff. Uh, 0:00:37.520 --> 0:00:40.280 here's something that I found helpful for me that I 0:00:40.280 --> 0:00:44.360 think it might help other dumb dumps, Like you're not 0:00:44.440 --> 0:00:46.879 a dumb dump. I like that trip. By the way, 0:00:46.920 --> 0:00:50.680 you click a circus peanut. It is circus peanut colored. 0:00:50.720 --> 0:00:53.920 Oh my god, that is circus peanut orange pent. Dude. 0:00:54.200 --> 0:00:57.279 I want to squeeze you do not um? All right, 0:00:57.360 --> 0:01:00.440 all right, you can squeeze you Ready for this? So 0:01:01.240 --> 0:01:05.679 if our solar system, which is the Sun and its 0:01:05.760 --> 0:01:11.399 orbiting planets, moons, dust, gas, a lot of dust and gas, 0:01:11.600 --> 0:01:16.320 solar system. Yeah, uh, if that was Let's say, if 0:01:16.360 --> 0:01:18.480 the Sun was the size of a grain of sand, 0:01:19.480 --> 0:01:22.560 then relatively our solar system would be like the size 0:01:22.600 --> 0:01:25.840 of our hand. With that at the center. And then 0:01:26.520 --> 0:01:32.640 if you extrapolate that, then our hand in relation to 0:01:32.680 --> 0:01:37.080 the Milky Way galaxy would stretch the length width of 0:01:37.080 --> 0:01:42.720 the United States and then keep going. Well, that's just 0:01:42.800 --> 0:01:45.600 one of you know, billions of galaxies in the universe 0:01:46.040 --> 0:01:49.520 if you go Solar system, galaxy, universe, and then so 0:01:49.680 --> 0:01:54.720 the universe would be like our the United States and Canada. Well, 0:01:54.800 --> 0:01:56.880 and I'm I am a dummy because I was like, 0:01:57.000 --> 0:02:00.320 and so let's stand in Lebanon, Kansas. Is as the 0:02:00.400 --> 0:02:04.880 geographic center not not as far as I recognize, But 0:02:04.920 --> 0:02:08.320 we're not at the geographic center of our solar system, 0:02:08.360 --> 0:02:10.280 is not the geographic center of the galaxy though, So 0:02:10.360 --> 0:02:13.040 I was wrong. No, there's a long history, by the way, 0:02:13.080 --> 0:02:16.440 it was beautiful. I love that, Thank you. Um, there's 0:02:16.480 --> 0:02:20.560 a long history of assuming that we are at the 0:02:20.600 --> 0:02:23.720 center of the universe, and then there's an equally almost 0:02:23.800 --> 0:02:27.400 equally long history of science proving that now we're absolutely not. 0:02:27.919 --> 0:02:31.560 And um, we finally figured out that we're about a 0:02:31.720 --> 0:02:36.040 quarter of the way between the galactic center and the 0:02:36.280 --> 0:02:40.800 edge of the Milky Way, and that checks out. So 0:02:40.840 --> 0:02:43.280 we're so we're nowhere near the center of the Milky Way. Well, 0:02:43.400 --> 0:02:45.760 because the center of the Milky Way is a supermassive 0:02:45.760 --> 0:02:50.519 black hole. The universe itself is expanding, and it's expanding 0:02:50.600 --> 0:02:54.000 faster than the speed of light, and galaxies are just 0:02:54.440 --> 0:02:58.200 caught up in the in the motion, going through the motions, 0:02:59.040 --> 0:03:01.239 and we're just here in this little rock called Earth 0:03:01.280 --> 0:03:04.000 trying to figure out what what in the age is 0:03:04.040 --> 0:03:07.720 going on? Yeah, during our you know, eighty to ninety 0:03:07.760 --> 0:03:11.960 years here. Yeah, we're so luckily though, we figured out 0:03:12.000 --> 0:03:14.919 how to encapsulate knowledge in the form of writing, so 0:03:15.040 --> 0:03:18.480 earlier generations can or later generations can build on the 0:03:18.520 --> 0:03:21.920 work of earlier generations, because we'd be toast if it 0:03:21.960 --> 0:03:26.400 all just got reset after everybody's lifetime and you couldn't say, oh, 0:03:26.440 --> 0:03:29.239 I've learned all this stuff. You know, people just keep 0:03:29.280 --> 0:03:32.320 discovering the same things, which would be great for that 0:03:32.400 --> 0:03:35.400 sense of discovery, but yeah, it wouldn't really help move 0:03:35.600 --> 0:03:39.760 our species forward now, And that's what we're all about here, right, Yeah, 0:03:40.560 --> 0:03:44.040 us and and the hubs um. So as far as 0:03:44.160 --> 0:03:46.960 what we know about galaxy is now compared to the 0:03:47.040 --> 0:03:50.400 very beginnings of this study. Of course, the Greeks were 0:03:50.840 --> 0:03:52.920 looking up at the sky a long time before we were, 0:03:53.240 --> 0:03:57.680 and they came up with this name galaxy's kuclose and 0:03:57.760 --> 0:04:01.520 it means milky circle. Yeah, and which guess which word 0:04:01.600 --> 0:04:06.200 we kept to describe galaxies, the milky not ku close. 0:04:06.400 --> 0:04:08.640 So when you're saying, like, looking at galaxy up there, 0:04:08.640 --> 0:04:11.480 you're saying, look at that milky up there. Oh right, right, 0:04:11.600 --> 0:04:14.560 ku closes circle. Yeah, I looked it up. I'm like, 0:04:14.600 --> 0:04:19.320 surely KU closes the milky one. But nope, no, surprising that. 0:04:19.440 --> 0:04:21.599 So but the Greeks were like, it looks like a 0:04:21.640 --> 0:04:24.320 milky circle, so we'll just go with that. Yeah. And 0:04:24.320 --> 0:04:26.600 they were onto some like kind of like everything they 0:04:26.600 --> 0:04:29.000 were doing back then, some stuff they got wrong, and 0:04:29.000 --> 0:04:31.320 we're kind of ahead of their time and they're thinking 0:04:31.320 --> 0:04:34.880 and other stuff they weren't quite right about because of technology. 0:04:34.920 --> 0:04:38.599 But Galileo did. He was He looked up and it's like, hey, 0:04:38.920 --> 0:04:40.640 that's a there's a bunch of stars up there. It 0:04:40.680 --> 0:04:44.000 ain't mile congregating for a reason. Yeah, And so we 0:04:44.120 --> 0:04:46.840 do pretty early on that, like we were in the 0:04:46.880 --> 0:04:50.480 midst of some sort of group of stars. But for 0:04:50.600 --> 0:04:53.560 most of the most of the era um where we 0:04:53.560 --> 0:04:55.200 were looking up at the sky, at least in the 0:04:55.240 --> 0:04:57.599 west I'm not sure about like the Muslim world. I 0:04:57.640 --> 0:05:00.400 know that they kind of had their own like track 0:05:00.560 --> 0:05:05.400 of astronomy and mathematics. It was, in many points in history, 0:05:05.560 --> 0:05:08.359 far more advanced than what the West was at. UM. 0:05:08.400 --> 0:05:11.160 But as far as the West is concerned, UM, they 0:05:11.160 --> 0:05:17.040 didn't understand that this group was anything less than the 0:05:17.160 --> 0:05:19.720 universe itself. They just looked out and they're like, well, 0:05:19.760 --> 0:05:21.880 there's the universe. Everything we're seeing is the universe, and 0:05:21.880 --> 0:05:25.520 that's all that there is. Not that Um. We possibly 0:05:25.560 --> 0:05:29.560 lived in what were later called by UM a guy 0:05:29.720 --> 0:05:34.120 named uh, I think Charles Messier who called them island 0:05:34.600 --> 0:05:39.520 island universes. No, I'm sorry, it was Harlow Shapley. In 0:05:39.520 --> 0:05:42.280 the early twentieth century. He started looking at some of 0:05:42.320 --> 0:05:44.840 these things and realized that they they had the same 0:05:44.880 --> 0:05:48.560 structure from that the Milky Way did we had kind 0:05:48.560 --> 0:05:51.560 of identified that we were in our own little galaxy, 0:05:51.600 --> 0:05:54.320 but that other stuff was beyond our own little galaxy, 0:05:54.400 --> 0:05:57.279 and that they were their own galaxies. And so these 0:05:57.320 --> 0:06:01.120 island universes came to be called milkies. Yeah, and so 0:06:01.440 --> 0:06:04.520 did you pronounce some Shapley, Yeah, there's an e that's 0:06:04.560 --> 0:06:06.960 not supposed to be in there because no one wants 0:06:07.000 --> 0:06:11.200 to be called Harlow Shapeley. I'm sure. Uh so he 0:06:11.240 --> 0:06:14.960 was actually right in this argument, right, this long standing 0:06:15.640 --> 0:06:20.320 um sort of disagreement but debate with Messi A no, 0:06:20.440 --> 0:06:22.880 Messi it was a couple hundred years before him. Well, 0:06:22.880 --> 0:06:25.000 but no, the whole argument though. I mean they didn't 0:06:25.000 --> 0:06:28.159 literally argue with each other because Messier was able to 0:06:28.240 --> 0:06:30.880 encapsulate his ideas in the form of writing. Yeah, but 0:06:30.960 --> 0:06:34.440 they had a long standing um again not to personal beef, 0:06:34.960 --> 0:06:38.880 but debate because we didn't have the technology to prove 0:06:38.920 --> 0:06:42.000 one or the other correct until Hubbs came along and 0:06:42.080 --> 0:06:46.839 in uh he basically said that Shapley was correct. Yeah, 0:06:46.920 --> 0:06:49.720 that that these little island universes weren't in the Milky Way. 0:06:49.760 --> 0:06:51.920 They were way far outside of the Milky Way. In 0:06:51.960 --> 0:06:55.440 the universe was astoundingly bigger than we we thought we 0:06:55.600 --> 0:06:59.919 previously imagined. So we mentioned Hubs, the hubs, Dr Hubble 0:07:00.760 --> 0:07:06.080 and it's awesome telescope, which did you know that's being replaced. 0:07:06.120 --> 0:07:08.040 I mean, I don't think they're gonna like destroy it, 0:07:08.080 --> 0:07:11.520 but surely not. It's being uh well, I guess sort 0:07:11.520 --> 0:07:16.480 of replaced by the James Webb space telescope. How do 0:07:16.520 --> 0:07:19.080 you mean being replaced, Like they're just gonna shoot it 0:07:19.080 --> 0:07:21.640 out of the sky with a space what I was saying, 0:07:21.640 --> 0:07:24.160 it out of field, destroy it. But it's being there's 0:07:24.160 --> 0:07:27.440 a new a new guy on the block, and everybody's 0:07:27.440 --> 0:07:30.040 hot and heavy, and his name is the James Webb Telescope, 0:07:30.360 --> 0:07:32.440 which will be I think now it's been pushed back 0:07:32.440 --> 0:07:35.920 to but this thing will supposed to be able to 0:07:35.960 --> 0:07:39.400 observe like the formation of galaxies pretty pretty much. The 0:07:39.840 --> 0:07:42.720 Hubble Telescope as it stands right now shows us I 0:07:42.720 --> 0:07:46.080 think back to like four million years after the Big Bang, 0:07:46.640 --> 0:07:51.680 which is astoundingly early in the universe's development. And the 0:07:51.720 --> 0:07:55.160 whole point of astronomy is what they're doing is looking 0:07:55.200 --> 0:07:58.160 back in time right the further away some object in 0:07:58.160 --> 0:08:01.160 the sky. Is what you're seeing then is what that 0:08:01.200 --> 0:08:03.680 object look like, say a billion or two billion, or 0:08:03.720 --> 0:08:06.240 ten billion years ago. And so you can take the 0:08:06.280 --> 0:08:08.840 structure of the object and compare it to objects that 0:08:08.880 --> 0:08:11.320 are much younger that we know of today. They're closer, 0:08:11.640 --> 0:08:13.840 and you can see how the universe has evolved, and 0:08:13.880 --> 0:08:15.760 we can learn, you know, figure out some of the 0:08:15.800 --> 0:08:17.880 mysteries of the universe, like where it came from, what 0:08:17.960 --> 0:08:22.280 its structure is like. Right, So if Hubble can if Hubble, 0:08:22.520 --> 0:08:26.040 that's great, great end of the world reference. But um, 0:08:26.080 --> 0:08:28.520 if Hubble can see back to four million years after 0:08:28.560 --> 0:08:31.560 the Big Bank, supposedly James Webb telescope can see back 0:08:31.560 --> 0:08:35.000 to like two hundred million years, that is a hair's 0:08:35.240 --> 0:08:39.960 breadth from the origin of the universe. Yeah, so it is. 0:08:40.120 --> 0:08:42.760 It's the big guy in town, the new sheriff. Yeah. 0:08:42.760 --> 0:08:44.720 I just don't want Hubs to get kicked to the curve. 0:08:45.080 --> 0:08:48.240 The James Wood telescope is gonna mush his face out 0:08:48.240 --> 0:08:51.200 of the way. Wait, you didn't say that James Wood's telescope. 0:08:51.600 --> 0:08:54.720 You would, You'd be like Trump forever the telescope full 0:08:54.720 --> 0:08:59.720 of right wing rage. Yeah, and very smart. I think 0:08:59.800 --> 0:09:02.839 he is the highest i Q of anyone in Hollywood. Really, 0:09:03.600 --> 0:09:07.120 he's like one sixthing. What he uh? Did you know 0:09:07.200 --> 0:09:13.400 that he supposedly tried to thwart the nine eleven hijacking? No? What, 0:09:13.640 --> 0:09:16.319 I think I need to look this up. Speaking from 0:09:16.360 --> 0:09:18.760 the top of my head, but I'm pretty sure that 0:09:18.880 --> 0:09:22.080 it is fact that he was on a flight with 0:09:22.840 --> 0:09:26.480 one of the ringleaders and was like this guy is 0:09:26.480 --> 0:09:29.760 on my flight and he's taken notes and something's fishy 0:09:29.800 --> 0:09:32.040 here and I'm going to report it. And that ended 0:09:32.120 --> 0:09:34.960 up being, you know, like Mohammed Atta or something. I 0:09:35.000 --> 0:09:38.800 gotta look that up because I'm truly like flying by 0:09:38.800 --> 0:09:40.040 the seat of my pants. But I think that's the 0:09:40.080 --> 0:09:43.080 true thing. He also made an appearance on The Simpsons. 0:09:44.240 --> 0:09:47.160 He was also the best part of the Stephen King 0:09:47.360 --> 0:09:50.640 anthology film Cat's Eye. I don't remember his is the 0:09:50.640 --> 0:09:53.960 man who tried to quit smoking? Is that what it 0:09:54.000 --> 0:09:57.000 was called? Yeah, you remember that? That was him. I 0:09:57.040 --> 0:09:59.360 don't remember James Witsby man. I think he was the 0:09:59.400 --> 0:10:01.680 guy that is trying to quit smoking under threat of 0:10:02.200 --> 0:10:05.679 violence to his family. Remember that. I haven't seen that 0:10:05.679 --> 0:10:08.200 in a while. I have to check that out. Sure 0:10:08.200 --> 0:10:13.320 it's being rebooted, all right, that's because it's space, alright. 0:10:13.360 --> 0:10:19.400 So the various shapes edwin the hubs. Hubble classified these 0:10:20.120 --> 0:10:25.840 uh and his Hubble sequence as elliptical, spiral, and irregular elliptical. 0:10:26.520 --> 0:10:28.760 I mean, we'll go into detail in these, but about 0:10:28.800 --> 0:10:34.320 six of all galaxies are elliptical roughly or so or spiral, 0:10:34.640 --> 0:10:39.600 which is us and then anywhere from one irregular. Yes, 0:10:40.760 --> 0:10:46.040 but elliptical, are there. There's a range of shape from circular, 0:10:46.120 --> 0:10:48.559 which is E zero, all the way up to EAT seven, 0:10:48.559 --> 0:10:54.199 which is the most elliptical, pretty much. Yeah, and you're like, okay, great, 0:10:54.280 --> 0:10:56.560 so all you need is elliptical, it's all galaxies are. 0:10:57.080 --> 0:11:00.360 But no, there's also something called spiral. And even though 0:11:00.679 --> 0:11:04.840 Hubble classified them by their shape, it's really they're more 0:11:05.200 --> 0:11:10.960 differentiated by their features and how bright right, right, they're bright. 0:11:11.000 --> 0:11:13.920 They have stars, bright stars, lots of hot gas. They 0:11:13.960 --> 0:11:17.480 tend to have arms that stretch out from them. Yeah. Like, 0:11:17.559 --> 0:11:19.880 if you looked at pictures of the Milky Way galaxy, 0:11:19.920 --> 0:11:23.679 it looks like a what does it look like like 0:11:24.200 --> 0:11:27.920 someone spinning an octopus? A bit of a whirlpool? Sure, 0:11:28.400 --> 0:11:32.280 it's spinning an octopus. I love that. Yeah, that was perfect. 0:11:32.360 --> 0:11:35.160 That's what I wish. That's what the Greeks had come 0:11:35.240 --> 0:11:38.760 up with instead of a Milky wayn't although they all 0:11:38.800 --> 0:11:40.480 they saw was like a strip of white light, and 0:11:40.679 --> 0:11:42.560 no one had any idea what the Milky Way looked 0:11:42.559 --> 0:11:45.880 like until the twentieth century, so they all, right, all 0:11:45.920 --> 0:11:49.160 these off the Greeks, everybody, I'm sorry, so, but spiral 0:11:49.200 --> 0:11:52.240 are the brightest, right, they're the brightest because they have 0:11:52.280 --> 0:11:56.440 the most bright stars um. Elliptical tend to sometimes not 0:11:56.520 --> 0:12:00.240 have any bright stars at all. UM. And then the 0:12:00.280 --> 0:12:04.400 other big difference between them is that elliptical are um 0:12:05.520 --> 0:12:10.000 are disordered and chaotic, whereas spiral are much more orderly. 0:12:10.040 --> 0:12:14.120 Where everything in the galaxy rotates in orbit around the 0:12:14.120 --> 0:12:16.640 galaxy center in the exact same way and for the 0:12:16.679 --> 0:12:20.800 exact same reasons that Earth rotates around the Sun, except 0:12:20.840 --> 0:12:24.079 in this rotation, our solar system takes about two d 0:12:24.240 --> 0:12:26.160 and thirty million years to make it all the way 0:12:26.160 --> 0:12:29.760 around the Milky Way, rather than one year around the Sun. Yeah, 0:12:29.800 --> 0:12:32.120 that's a big death. Yeah it is. And again with 0:12:32.160 --> 0:12:35.720 the size as illustrated at the onset, that might make 0:12:35.720 --> 0:12:38.160 a little more sense. Sure, the grain of sand in 0:12:38.200 --> 0:12:40.440 the palm palm in the middle of the United States, 0:12:40.559 --> 0:12:43.600 it's actually let's say the United States was that would 0:12:43.600 --> 0:12:48.960 place us like, I don't know what, Kentucky? What the 0:12:49.000 --> 0:12:50.960 center of the US? No, no, no, If the center 0:12:50.960 --> 0:12:56.680 of the U s is leban On, Kansas, what is 0:12:56.720 --> 0:13:01.079 in your book? I'll tell you. Got my own opinions 0:13:01.120 --> 0:13:03.520 on that. Just no credit to leban On, Kansas, I 0:13:03.600 --> 0:13:06.000 get it. Um I think it's actually a couple of 0:13:06.000 --> 0:13:08.400 miles from there, but I don't know where that would 0:13:08.440 --> 0:13:10.080 put us if we're in the like the what the 0:13:10.480 --> 0:13:12.400 a third of the way between the edge and I 0:13:12.400 --> 0:13:14.680 see what you're saying. If leban On, Kansas is the 0:13:14.679 --> 0:13:17.440 middle and you not though, but let's just for the 0:13:17.480 --> 0:13:21.240 sake of our in the east coast edge would the 0:13:21.240 --> 0:13:23.200 outer edge? What would that put us? Yeah, I think 0:13:23.280 --> 0:13:26.040 Kentucky is probably a pretty good roughly Kentucky or maybe 0:13:26.080 --> 0:13:32.440 East Tennessee or Middle Tennessee something like that. Yeah, somewhere between, 0:13:32.840 --> 0:13:38.120 just not in Memphis. Uh. Then the spirals are broken 0:13:38.160 --> 0:13:45.120 down and subdivided into other categories. Um normal spiral. That's 0:13:45.160 --> 0:13:48.520 where you have. That's sort of the classic disc shape 0:13:48.559 --> 0:13:50.960 that we're thinking of, right, Yeah, that's the other feature 0:13:51.000 --> 0:13:53.120 that they have is like a hump. They look like 0:13:53.120 --> 0:13:58.000 a ufolge if you looked at a spiral galaxy from 0:13:58.040 --> 0:14:02.000 the side especially, I guess in all right s A, 0:14:02.679 --> 0:14:06.439 I think in A. Yeah, that's the largest nuclear pulge. 0:14:06.920 --> 0:14:10.480 Nuclear bulges. So it's like great band name, it really is. 0:14:11.040 --> 0:14:12.840 But the bulge is like it's got a hump on 0:14:12.880 --> 0:14:14.600 the top and a hump on the bottom and then 0:14:14.600 --> 0:14:17.800 a disc of stuff in the middle like a UFO. 0:14:17.960 --> 0:14:20.880 That's what it looks like. Um, that's a that's a 0:14:20.920 --> 0:14:26.200 classic spiral galaxy, right, which would be the normal. Then 0:14:26.240 --> 0:14:29.600 they're the barred spiral that is has a disc shape 0:14:29.640 --> 0:14:32.440 as well, with a bright center as well. I don't 0:14:32.440 --> 0:14:38.160 get the difference then visually, so I think the difference is, Um, 0:14:38.560 --> 0:14:45.760 the disc shape is with the barred spiral, the center 0:14:45.800 --> 0:14:50.080 of it is drawn out so like in a in 0:14:50.120 --> 0:14:53.680 a normal spiral, it's just a nice circle in the center, 0:14:53.720 --> 0:14:56.640 a nice tidy sphere in the center, whereas in a 0:14:56.720 --> 0:14:59.720 barred spiral that sphere is pulled out into an elliptical 0:14:59.760 --> 0:15:03.280 it's self. So it's like a bar of light going 0:15:03.320 --> 0:15:06.040 through you know, the middle of the galaxy, and that's 0:15:06.120 --> 0:15:09.280 the galactic center and nucleus, all right. Uh. And then 0:15:09.280 --> 0:15:13.760 we have our irregular as the third type of galaxy shape. Uh. 0:15:13.760 --> 0:15:18.080 And these are very faint, very small Um, no bright center, 0:15:18.160 --> 0:15:25.640 no spiral arms, just losers of the loser galaxies. So 0:15:26.000 --> 0:15:29.640 they used to think that this was the evolution of galaxies, 0:15:29.680 --> 0:15:33.360 that the different galaxies was like, yeah, either it started 0:15:33.360 --> 0:15:37.160 as elliptical and then moved to um spiral or most 0:15:37.200 --> 0:15:39.760 likely vice versa. Now we found that's not the case 0:15:39.800 --> 0:15:42.760 at all. Interesting and they think probably you know, um, 0:15:42.760 --> 0:15:47.360 galaxies tend to start out as spiral galaxies, the ordered 0:15:47.440 --> 0:15:50.520 kind where everything's just going around nice and easy. Um, 0:15:51.120 --> 0:15:56.720 and that the reason we have elliptical galaxies, the disordered kind, 0:15:57.000 --> 0:15:59.920 is because a spiral merged with another spiral, which will 0:16:00.000 --> 0:16:03.160 it into later. Yeah, the collisions of galaxies, yeah, which 0:16:03.200 --> 0:16:07.080 I honestly didn't know that much about until this episode. Yeah, 0:16:07.120 --> 0:16:09.240 and it sounds a lot scarier than it is. Certainly 0:16:09.280 --> 0:16:11.960 not that scary, So don't be scared, everybody. You probably 0:16:11.960 --> 0:16:15.160 wouldn't even notice. You just have an extra son five 0:16:15.200 --> 0:16:18.600 billion years from there. I feel like we should take 0:16:18.600 --> 0:16:20.520 a break. I think we should too. We made it 0:16:20.520 --> 0:16:22.880 through page one, all right, we'll come back with page 0:16:22.880 --> 0:16:51.080 to right after this, alright, chuck. So we're talking spiral 0:16:51.120 --> 0:16:54.120 galaxies because that's what we care about, because that's what 0:16:54.160 --> 0:16:57.200 the Milky Way is. That's right. Um, it's a spiral 0:16:57.240 --> 0:17:00.960 bar galaxy to be particular. And so it's got that 0:17:01.120 --> 0:17:05.280 center hump the galactic disc, and the galactic disc is 0:17:05.320 --> 0:17:08.120 actually made up of a few different parts too. You've 0:17:08.119 --> 0:17:12.200 got the nucleus, which is the center. You've got the bulge, 0:17:12.720 --> 0:17:16.879 which you love the nuclear bulge like nine times already, 0:17:17.880 --> 0:17:22.240 and then the spiral arms. These are like um accumulations 0:17:22.240 --> 0:17:26.919 of stars, gas, dust, um, all sorts of stuff, planet, 0:17:26.960 --> 0:17:29.560 solar systems, all that, And that's where we are right. 0:17:29.600 --> 0:17:32.000 We're in a spiral arm. The Milky Way has four 0:17:32.040 --> 0:17:34.840 spiral arms, two major and two minor, and we're in 0:17:34.840 --> 0:17:38.120 a minor one Oriyan, which is still It's fine. We're 0:17:38.119 --> 0:17:40.280 in a minor arm, but it's the orion arm, which 0:17:40.280 --> 0:17:42.439 makes it pretty cool. So I guess it would not 0:17:42.520 --> 0:17:45.240 have been a octopus spinning. That would be eight arms. 0:17:45.640 --> 0:17:48.119 Well maybe we haven't discovered the other four yet, yes, 0:17:48.280 --> 0:17:50.919 or maybe we're just a ceiling fan. Maybe. So I 0:17:51.000 --> 0:17:54.440 like the spinning octopus the most. We need to get 0:17:54.480 --> 0:17:56.920 some more arms. Then, you know, you shouldn't need octopus. 0:17:57.000 --> 0:18:03.520 They're extraordinarily intelligent. Just y. I think we we've sung 0:18:03.520 --> 0:18:07.040 our octopus praises over the years. But do you you're 0:18:07.080 --> 0:18:09.080 you eating them those still, is what I'm saying. No, 0:18:09.240 --> 0:18:13.560 I don't need octopus. Yeah, did you give them up 0:18:13.600 --> 0:18:15.879 after our episode on it? Or yeah, we're on that 0:18:15.920 --> 0:18:18.480 time is it okay to eat squid inc pasta? Though 0:18:19.920 --> 0:18:22.719 squid they're stupid. Who cares about squid? I'll eat them 0:18:22.760 --> 0:18:25.359 all day long. Luckily, that's what most calamaria is, a 0:18:25.440 --> 0:18:30.080 squid or not even right? What is it? Then? In't 0:18:30.080 --> 0:18:32.400 there like a big calamari hoax going on? I can 0:18:32.440 --> 0:18:34.840 believe it's Some of that stuff is awfully rubbery. Yeah, 0:18:35.119 --> 0:18:37.239 I think that's the deal, all right. So back to 0:18:37.320 --> 0:18:42.080 the back to the shape of the galactic disc. There's 0:18:42.119 --> 0:18:45.840 also the globular cluster um these are above and below 0:18:45.880 --> 0:18:49.960 that disk, and then the halo, which is um hot 0:18:50.000 --> 0:18:53.520 gas we think, and that is that that sort of 0:18:53.600 --> 0:18:56.560 dim region that you see around the galaxy right when 0:18:56.560 --> 0:18:58.320 you think of like the Milky Way from all the 0:18:58.320 --> 0:19:01.480 pictures you've ever seen. What you're mostly thinking about is 0:19:01.520 --> 0:19:06.080 the galactic disc. Popular clusters nobody really thinks much about. 0:19:06.200 --> 0:19:12.880 But they're actually old super um, super burned out ancient 0:19:13.000 --> 0:19:17.040 clumps of stars that formed in like the early galaxy, 0:19:17.200 --> 0:19:19.000 that used up a bunch of stars, used up their 0:19:19.040 --> 0:19:21.320 fuel really quickly, and now they're just kind of like 0:19:21.359 --> 0:19:26.399 these dead balls that are in orbit around our galaxy 0:19:26.640 --> 0:19:28.879 and we actually can use them and the effect that 0:19:28.920 --> 0:19:32.919 our galaxy has on them. The title effects of gravity 0:19:32.960 --> 0:19:36.320 to figure out how much mass our galaxy has. Yeah, 0:19:36.359 --> 0:19:39.440 and you know gravity is what's holding all of this together. 0:19:39.640 --> 0:19:41.399 And you would think when you see it's something like 0:19:41.400 --> 0:19:45.600 the Milky Way galaxy. Uh, and you know gravity is 0:19:45.720 --> 0:19:48.800 dependent upon mass, that that center would be where all 0:19:48.840 --> 0:19:51.480 the masses. But that's not the case. It's a little 0:19:51.480 --> 0:19:53.760 bit opposite of what you might think. Yeah, that that 0:19:53.880 --> 0:19:57.560 um outer halo has about as much mass as the 0:19:57.640 --> 0:20:02.720 intergalactic disc um the counterintuitive. Yeah, and because that halo 0:20:02.800 --> 0:20:06.520 is made up mostly of gas and some dust um, 0:20:06.600 --> 0:20:10.240 it's actually orbiting or rotating at a different rate or 0:20:10.280 --> 0:20:13.640 different velocity I guess than the galactic disc. So there's 0:20:13.640 --> 0:20:16.760 actually torque that gets produced because the galactic disc is 0:20:16.760 --> 0:20:21.120 like dragging it along the arms. No, we found out recently, 0:20:21.119 --> 0:20:23.280 like within the last month or two. I believe that 0:20:23.320 --> 0:20:28.119 the actual the actual Milky Way galaxy is bent on 0:20:28.280 --> 0:20:30.960 the ants. Like so it looks like an s from 0:20:30.960 --> 0:20:33.840 the site, kind of like a sombrero with like the 0:20:33.880 --> 0:20:38.120 front up and the back down. That's what the milky is. 0:20:38.280 --> 0:20:41.800 Not an octopus, not the only fan. It's a crumpled sombrero, 0:20:42.240 --> 0:20:47.280 maybe a nacho sombrero like the one Homer Simpson war. Right, 0:20:47.280 --> 0:20:49.680 are the guys that make just wear the cowboy hat 0:20:49.720 --> 0:20:52.080 with a front brim turned up like the cook at 0:20:52.119 --> 0:20:57.119 the at the Cowboy camp. Sure, cookie cookie cook. Yeah. 0:20:57.160 --> 0:21:00.720 And galaxies are very very far apart from one another. 0:21:01.480 --> 0:21:05.040 The closest one to us, Uh, Andromeda is two point 0:21:05.080 --> 0:21:08.640 two million light years away from us. And uh that's 0:21:08.640 --> 0:21:11.760 a I mean, that's relatively close in the grand scheme, 0:21:12.320 --> 0:21:15.240 but that's also pretty far apart. So I want to 0:21:15.280 --> 0:21:19.280 there's this professor Barbara Ryden from Ohio State whose lecture 0:21:19.320 --> 0:21:22.520 we came across, and she like just nails this right. 0:21:22.960 --> 0:21:27.720 Two point two million light years is an astoundingly large distance, Right, 0:21:28.280 --> 0:21:32.320 but it's actually really close for a galaxy because galaxies 0:21:32.359 --> 0:21:34.840 are so huge. And the way that she put it, 0:21:34.920 --> 0:21:38.520 like if you took a pair of ping pongs and 0:21:38.560 --> 0:21:42.760 said one was balls ping pong balls, Yes, games of 0:21:42.800 --> 0:21:45.200 ping pong, and he took two games. If you took 0:21:45.280 --> 0:21:48.919 two ping pong balls and one was the Sun and 0:21:49.040 --> 0:21:54.040 one was a neighboring star to the Sun, Alpha Centauri, okay, uh, 0:21:54.040 --> 0:21:58.639 and you you put them relative to one another. Uh, 0:21:58.760 --> 0:22:02.080 the ping pong balls would be as far apart as Columbus, 0:22:02.119 --> 0:22:06.120 Ohio and Jacksonville, Florida. Okay, if you use ping pong 0:22:06.160 --> 0:22:09.959 balls to be Andromeda and the Milky Way, here we go. 0:22:10.040 --> 0:22:15.120 The distance would be three ft relative to one another. Interesting, 0:22:15.359 --> 0:22:17.800 it is interesting. Yeah, yeah, it's at least as interesting 0:22:17.800 --> 0:22:20.560 as your grain of singing in the palmyre this less 0:22:20.600 --> 0:22:22.639 than one big mac. Maybe I didn't get it across. 0:22:22.720 --> 0:22:24.760 Let me try another take. Okay, No, I thought it 0:22:24.760 --> 0:22:29.560 was great. Um they use Uh, well, we should talk 0:22:29.600 --> 0:22:31.760 about parsecs a little bit, just because of the Star 0:22:31.760 --> 0:22:36.800 Wars thing, because a parsk is a unit of distance 0:22:37.359 --> 0:22:40.080 that is three point to six light years. And you 0:22:40.160 --> 0:22:44.240 remember in Star Wars the famous line from Han Solo. 0:22:45.240 --> 0:22:49.160 Remember that he made the Kessel run in twelve parsecs. So, 0:22:50.160 --> 0:22:52.399 as a young dumb kid, I thought that meant, you know, 0:22:52.680 --> 0:22:56.359 like a parsak was like whatever, thirty seconds. So he 0:22:56.400 --> 0:22:59.280 did this thing in a matter of minutes. Uh. And 0:22:59.320 --> 0:23:01.240 then when I learned that it was a unit of 0:23:01.280 --> 0:23:03.919 distance in that time, I think a lot of people's 0:23:03.920 --> 0:23:06.720 inclination would be that that would be a mistake on 0:23:06.800 --> 0:23:10.440 the part of the writer of Star Wars. But Star 0:23:10.480 --> 0:23:13.199 Wars nerds are quick to point out that did no, no, no, 0:23:14.040 --> 0:23:16.960 he he did mean a unit of distance, but he 0:23:17.000 --> 0:23:20.080 actually skirted very close to a black hole on his 0:23:20.280 --> 0:23:24.119 Kessel run and he actually shortened the normally eighteen par 0:23:24.240 --> 0:23:27.760 sect route to twelve par secs. Wow, that's a big, 0:23:27.880 --> 0:23:30.160 big short cut. So he cut out. He basically took 0:23:30.160 --> 0:23:34.040 a shortcut. Yeah, not bad. Yeah, I'm just kind of 0:23:34.080 --> 0:23:37.240 wondering this is, you know, all after the fact, and 0:23:37.320 --> 0:23:41.479 they were like, oh, yeah, I think so. I got 0:23:41.480 --> 0:23:44.600 a lot going for them. So as far as formation 0:23:44.640 --> 0:23:48.840 and the galaxy, again, we're talking about going back further 0:23:48.880 --> 0:23:52.480 than we can see with our current telescopes, even even 0:23:52.560 --> 0:23:55.399 the web one upcoming. But we do have some pretty 0:23:55.440 --> 0:23:59.159 good guesses, um that after the Big Bang about fourteen 0:23:59.200 --> 0:24:03.919 billion years ago is when these galaxies formed from again 0:24:04.080 --> 0:24:08.600