WEBVTT - How Planetariums Work 0:00:03.400 --> 0:00:12.600 Get in touch with technology. What's tech stuff from dot com? 0:00:12.720 --> 0:00:15.720 Hey there, and welcome to tech stuff. I'm Jonathan Strickland 0:00:15.760 --> 0:00:18.400 and I'm Lauren Fock Obama. And we thought today we 0:00:18.440 --> 0:00:21.560 would do a little star gazing. But we're not out 0:00:21.600 --> 0:00:25.279 doorsy types. Lauren. Uh, well, I mean we can be, 0:00:25.440 --> 0:00:27.800 but actually at night it's more or less fun. Yeah, 0:00:27.800 --> 0:00:31.120 it's really the sun gets us. But but anyway, sometimes 0:00:31.240 --> 0:00:34.320 sometimes you're just not able to really do some good 0:00:34.360 --> 0:00:37.280 star gazing depending upon where you are. Maybe it's overcast, 0:00:37.360 --> 0:00:39.519 or maybe there are other conditions will talk about that 0:00:39.600 --> 0:00:41.640 kind of prevents you from doing it. So where do 0:00:41.680 --> 0:00:44.800 you go for star gazing when the stars are not 0:00:44.840 --> 0:00:49.720 necessarily visible to you at that particular moment. Planetarium would 0:00:49.720 --> 0:00:52.840 be a pretty good option. Yes, it is not pronounced 0:00:52.840 --> 0:00:56.240 as Matt Frederick would say, as a planet arium. It's 0:00:56.240 --> 0:01:00.840 a planetarium which is essentially uh in enclosed with an 0:01:00.920 --> 0:01:04.480 artificial sky that has stars and sometimes plants and sometimes 0:01:04.480 --> 0:01:08.560 other celestial bodies represented some kind of space scape. Yeah. 0:01:08.720 --> 0:01:11.640 So there are a lot of different types of planetariums 0:01:11.640 --> 0:01:14.800 that all use a very similar approach, but you know, 0:01:14.840 --> 0:01:17.480 the actual implementation can differ between one and the other. 0:01:17.959 --> 0:01:21.040 But we wanted to talk more about all of the 0:01:21.800 --> 0:01:24.640 kind of history that built into coming up to the 0:01:24.640 --> 0:01:27.320 planetariums as well as how they actually work. Right. We 0:01:27.360 --> 0:01:30.040 didn't want to just explain it's a projector and then 0:01:30.120 --> 0:01:33.240 go in from there. I mean, because because basically it's 0:01:33.240 --> 0:01:35.520 a projector. Yea, So we could just say it's a projector, 0:01:35.560 --> 0:01:39.640 and if you know how a projector, it's a Friday, 0:01:39.640 --> 0:01:42.240 so we're ready to go home. But no, we wanted 0:01:42.240 --> 0:01:45.679 to actually talk about the history of planetariums because it's 0:01:45.720 --> 0:01:49.720 a fascinating story. I mean, obviously, as as a species, 0:01:49.840 --> 0:01:54.960 humans have been fascinated with the heavens since before recorded history. 0:01:55.240 --> 0:01:58.440 I mean, this is something that we've obviously been really 0:01:59.200 --> 0:02:03.560 amazed by over thousands of years. It's pretty amazing. And 0:02:03.920 --> 0:02:06.480 what's interesting is that there have been lots of different 0:02:06.760 --> 0:02:13.880 attempts to create a an indoor version of this experience, 0:02:14.360 --> 0:02:17.040 because it's not always convenient to go outside and do 0:02:17.120 --> 0:02:20.320 all your your work. And based upon thousands of years 0:02:20.320 --> 0:02:24.000 of observations, we got pretty good at figure out how 0:02:24.040 --> 0:02:26.600 to represent the night sky in a way that was 0:02:26.639 --> 0:02:29.880 accurate even with the movement of things like planets in 0:02:29.919 --> 0:02:34.079 the moon and the Sun and Earth itself. Yeah, I 0:02:34.120 --> 0:02:35.720 mean it took us a while to figure that part out, 0:02:36.240 --> 0:02:39.560 that the Earth itself was moving and not say everything 0:02:39.560 --> 0:02:42.280 else was moving around the Earth. And depending upon whom 0:02:42.320 --> 0:02:45.919 you are, you might still argue that thinking of a 0:02:45.960 --> 0:02:51.120 specific documentary that Jane Way was the voice for anyway. So, 0:02:51.680 --> 0:02:55.040 assuming you're not having this geocentric view, even even that 0:02:55.400 --> 0:02:58.799 would allow you to see that the the heavens move 0:02:58.919 --> 0:03:01.840 in a very pretty actable way. It may take a 0:03:01.880 --> 0:03:04.440 long time for a particular cycle to happen, but once 0:03:04.520 --> 0:03:07.120 you know what those cycles are, you could predict make 0:03:07.200 --> 0:03:12.720 observations that would end up either verifying or or negating 0:03:12.800 --> 0:03:16.880 the previous guesswork, and eventually you make it into a science. 0:03:16.919 --> 0:03:24.680 So why our planetariums themselves awesome? Well, for one, you 0:03:24.680 --> 0:03:26.760 get to look at the stars, even if again you 0:03:26.800 --> 0:03:29.040 are in a place where you can't normally see them, 0:03:29.040 --> 0:03:31.359 like here in Atlanta, we get a lot of what's 0:03:31.400 --> 0:03:35.040 called light pollution. So that's just a you know, any 0:03:35.240 --> 0:03:37.680 major city tends to have this where you've got lots 0:03:37.680 --> 0:03:40.160 of lights that are on at night, and that tends 0:03:40.240 --> 0:03:42.440 to drown out some of the stars. You can't see 0:03:42.480 --> 0:03:44.680 the fainter ones. You really only see the brightest ones 0:03:44.720 --> 0:03:47.000 that are in the sky. Uh. You know, you might 0:03:47.000 --> 0:03:48.960 be able to see things like Venus, which are that's 0:03:48.960 --> 0:03:51.840 that's extremely bright, and you might see some of the 0:03:51.880 --> 0:03:55.440 major stars and some of the major constellations, but you're 0:03:55.440 --> 0:03:58.440 missing out on a lot certainly. So unless you go 0:03:58.600 --> 0:04:01.000 way out into the middle of no Aware where there 0:04:01.040 --> 0:04:03.640 aren't so many lights, or you have to live someplace 0:04:03.680 --> 0:04:06.560 that has really strict rules about the lights at night. 0:04:06.720 --> 0:04:09.440 Because there are a few of those places, you probably 0:04:09.600 --> 0:04:11.960 can't see that many. And even in those places it 0:04:12.040 --> 0:04:16.040 sometimes rains or gets cloudy. It turns out clouds really 0:04:16.080 --> 0:04:19.680 inhibit the star gazing activities. Also, the sky over the 0:04:19.760 --> 0:04:23.559 Southern Hemisphere is different than that over the Northern Hemisphere. So, um, 0:04:23.600 --> 0:04:27.279 if if you don't travel back and forth pretty frequently 0:04:27.400 --> 0:04:30.200 between the two, Yeah, if you don't cross the line 0:04:30.560 --> 0:04:33.280 over at the equator and shout out to all my 0:04:33.360 --> 0:04:37.360 navy buddies who do um, if you don't do that frequently, yeah, 0:04:37.520 --> 0:04:39.480 you know, you miss out on the way the sky 0:04:39.640 --> 0:04:42.320 looks and in the Southern hemisphere, or if you live 0:04:42.360 --> 0:04:45.040 in the Southern hemisphere the Northern hemisphere, so I'll fly 0:04:45.160 --> 0:04:47.039 to our New Zealand listeners. There's a lot of you. 0:04:47.240 --> 0:04:49.600 There's actually quite a few of you. UM. I will 0:04:49.640 --> 0:04:52.800 not confuse you with the Australian listeners, please don't we 0:04:52.800 --> 0:04:56.800 We love all of you equally. So if you've never 0:04:56.880 --> 0:04:58.719 been there, but you want to see what the sky 0:04:58.880 --> 0:05:02.400 looks like up Manitarium, some of them, anyway, can accommodate you. 0:05:02.480 --> 0:05:05.719 A lot of them have the capability of showing the 0:05:05.960 --> 0:05:09.479 stars over any particular point on Earth. Like That's how 0:05:09.560 --> 0:05:13.559 sophisticated they've become. So not only that, but they many 0:05:13.640 --> 0:05:15.800 of them can also show you what the sky would 0:05:15.800 --> 0:05:18.520 look like on any given date. So you might say, well, 0:05:18.520 --> 0:05:21.080 what did the sky look like yesterday? What will it 0:05:21.120 --> 0:05:24.040 look like tomorrow? What will it look like in a century? 0:05:24.200 --> 0:05:26.840 What will it look like a hundred centuries from now? 0:05:26.880 --> 0:05:28.839 What did it look like back in the day that 0:05:29.240 --> 0:05:32.039 Shakespeare wrote his plays? Like, you could do any of 0:05:32.040 --> 0:05:34.320 those things, and by plugging in some some numbers. The 0:05:34.360 --> 0:05:39.080 computers that handle the calculations for most of these uh devices, 0:05:39.120 --> 0:05:40.679 not all of them, some of them are a little older, 0:05:40.680 --> 0:05:43.840 but most of them can take that into consideration and 0:05:44.000 --> 0:05:47.480 actually determine what the position of the planets would be 0:05:47.520 --> 0:05:51.240 on any given date, the stars, etcetera, which is pretty awesome. Yeah. Um, 0:05:51.279 --> 0:05:54.440 they can also be used to teach celestial navigation, and 0:05:54.560 --> 0:05:57.240 they certainly were used for that purpose during World War two. 0:05:57.520 --> 0:06:02.640 Very useful, especially if you can't always depend upon instruments 0:06:02.720 --> 0:06:09.360 to be able to get around. Also, hey, it teaches astronomy. Yeah, 0:06:09.680 --> 0:06:11.760 you know, I always almost left that out of the notes, 0:06:11.920 --> 0:06:14.320 and I was like, yeah, that's a that's a big deal. 0:06:14.440 --> 0:06:17.960 I guess that's the thing. Yeah. So obviously the astronomers 0:06:18.000 --> 0:06:20.719 out there if you want to be able to identify 0:06:21.520 --> 0:06:24.640 various star clusters things like that, and a lot of 0:06:24.680 --> 0:06:28.320 these have special um projectors that will show things like 0:06:28.320 --> 0:06:31.520 the Milky Way galaxy or other nebula or things like that. 0:06:32.080 --> 0:06:34.400 And that's important. Oh sure, sure, but we will get 0:06:34.400 --> 0:06:37.960 into that later on. Um, let's talk for right now 0:06:38.040 --> 0:06:40.680 about the history of these devices, because people have been 0:06:40.720 --> 0:06:45.440 painting the sky on ceilings I mean for for basically ever. Yeah, 0:06:45.480 --> 0:06:48.040 I mean, like I got a cousin who has the 0:06:48.080 --> 0:06:51.000 Glow in the Dark ones that's been on her her 0:06:51.040 --> 0:06:54.919 bedroom ceiling like since she was like four. So yeah. Also, 0:06:54.960 --> 0:06:56.919 there's a star map on the ceiling of the tomb 0:06:56.960 --> 0:07:02.920 of the Egyptian official sinement that dates from that does 0:07:03.000 --> 0:07:05.760 predate my cousin, so a little bit your your argument 0:07:05.800 --> 0:07:08.919 is valid. Yeah, I mean this is something, like I said, 0:07:09.160 --> 0:07:12.040 humans have been fascinated with the stars for as long 0:07:12.080 --> 0:07:15.640 as we've been looking around and being able to express 0:07:15.680 --> 0:07:19.880 our thoughts. So it's no surprise that we're seeing evidence 0:07:19.920 --> 0:07:23.360 of that in in prehistoric and and uh, you know, 0:07:23.960 --> 0:07:30.200 just post historic, fairly historic uh, you know, drawings and 0:07:30.200 --> 0:07:33.520 and uh and depictions on things like this tomb. And 0:07:33.640 --> 0:07:36.720 then we have some early examples of what could be 0:07:36.840 --> 0:07:41.600 something like a planetarium from the Arabic world right right there, 0:07:41.720 --> 0:07:44.880 there were Arabic tents made with holes in the fabric 0:07:44.920 --> 0:07:48.440 to let outside lights shine through, representing each star or 0:07:48.560 --> 0:07:51.000 each star as they knew them. And in that time 0:07:51.440 --> 0:07:55.320 um described in European History Circle that twelve hundreds are 0:07:55.360 --> 0:07:57.760 so and so that's that's you know, that's a good 0:07:57.760 --> 0:08:01.440 while back, right and then we had, uh, let's let's 0:08:01.520 --> 0:08:04.720 switch up to say, oh, I don't know, let's let's 0:08:04.760 --> 0:08:08.000 go to the idea of using globes and sky maps. 0:08:08.000 --> 0:08:09.840 This is really cool too. So starting a couple of 0:08:09.880 --> 0:08:12.400 thousand years ago, it became really popular in the West 0:08:12.480 --> 0:08:15.480 to draw sky maps on globes, and um the first 0:08:15.720 --> 0:08:18.920 planetarium is known to history. Were huge versions of these, 0:08:19.000 --> 0:08:21.600 like big enough for people to sit in. A really 0:08:21.600 --> 0:08:24.800 famous example is the gor Top Globe, supposedly based on 0:08:24.880 --> 0:08:28.800 plans found among Tico Brahe's papers. Okay, so wait, wait, wait, 0:08:29.040 --> 0:08:31.680 Tico Bray. I've always heard Tycho Bray. Where did you 0:08:31.680 --> 0:08:35.120 hear Tico Brian. I'm one of my astronomy professors in 0:08:35.400 --> 0:08:38.720 college called him Tico. That's good enough for me. So 0:08:38.880 --> 0:08:40.880 I know, I know that the Penny Arcade dude calls 0:08:40.960 --> 0:08:46.640 himself Tycho, but hey, we're going with an astronomy professor's approach. 0:08:46.720 --> 0:08:49.319 I'm I'm all right with bowing to authority on this one. 0:08:50.360 --> 0:08:53.880 He had a really impressive beard, so that also, I mean, 0:08:54.080 --> 0:08:58.240 that's like credentials in the astronomy world. So that's totally cool. 0:08:58.720 --> 0:09:00.319 So that that was that was built in the mid 0:09:00.400 --> 0:09:02.960 sixteen hundreds and what's now Germany, and it was large 0:09:03.080 --> 0:09:05.520 enough for like twelve people to sit in on these 0:09:05.520 --> 0:09:09.480 circular benches that were around a table um where refreshments 0:09:09.480 --> 0:09:12.959 could be served. Obviously, um so, so the So the object, 0:09:13.000 --> 0:09:16.160 this globe was about ten ft or three meters in diameter, 0:09:16.600 --> 0:09:20.439 and the stars in it were these gilded, spangled fixtures 0:09:20.480 --> 0:09:23.440 in the inside surface of the globe that we're eliminated 0:09:23.440 --> 0:09:25.319 by a lamp that would sit on the table along 0:09:25.360 --> 0:09:28.200 with your you know, snaky cakes. Interesting. So it's like 0:09:28.600 --> 0:09:32.320 it's like if you look at a regular globe, you know, 0:09:32.360 --> 0:09:34.440 that's something that we look at on the outside surface 0:09:34.640 --> 0:09:37.120 obviously that's you know, representing the Earth. But this is 0:09:37.160 --> 0:09:39.680 one where we would go on the inside and we're 0:09:39.679 --> 0:09:43.320 looking at the inner wall, which is representing the heavens, 0:09:43.320 --> 0:09:45.400 the heavens right right, and the outside of it was 0:09:45.440 --> 0:09:48.480 actually painted like like the Earth. It had all of 0:09:48.480 --> 0:09:50.560 the continents and everything on it. Pretty cool that whole 0:09:50.559 --> 0:09:53.559 globe shell could could rotate around the viewers thanks to 0:09:53.600 --> 0:09:56.520 some water powered machinery. And it took some ten years 0:09:56.559 --> 0:10:00.960 to build and weighs like three tons, despite which it 0:10:01.000 --> 0:10:03.360 was moved to St. Petersburg as a gift to Peter 0:10:03.440 --> 0:10:08.040 the Great in seventeen seventeen. Shortly after that, it was 0:10:08.880 --> 0:10:12.560 partially destroyed in a fire, then restored, then stolen by 0:10:12.600 --> 0:10:15.880 the Germans in World War Two, found by US troops 0:10:15.960 --> 0:10:20.000 and restored again to St. Petersburg. I'm pretty sure that 0:10:20.040 --> 0:10:23.120 should be an Indiana Jones plot. All right, it's great, 0:10:23.120 --> 0:10:27.600 and this thing weighs three tons. It takes some determination 0:10:27.880 --> 0:10:31.559 to steal anything that weighs three tons. That's pretty incredible. 0:10:31.840 --> 0:10:35.720 But so the practice of making these these enterable sky 0:10:35.800 --> 0:10:39.079 globes like this unwieldy as they were persisted into the 0:10:39.160 --> 0:10:43.120 nineteen hundreds. The Museum of the Chicago Academy of Sciences 0:10:43.160 --> 0:10:46.920 built their Atwood globe as late as nine um and 0:10:46.920 --> 0:10:48.920 and that's that's about the same size, a little bigger 0:10:48.920 --> 0:10:51.480 at measure sixteen feet, that's about five meters in diameter 0:10:52.000 --> 0:10:55.560 um and shows six nine two stars plus the planets 0:10:55.600 --> 0:10:58.760 in our solar system, as as holes through which outside 0:10:58.840 --> 0:11:02.440 light can shine. It's electric and the shell can spin 0:11:02.559 --> 0:11:06.520 once every eight minutes around viewers. Interesting, and so this 0:11:06.640 --> 0:11:09.120 is kind of it's it's like it's taking a note 0:11:09.160 --> 0:11:12.000 back from those old Arabic tents, right the lights coming 0:11:12.040 --> 0:11:15.760 from outside shining through holes, and that's what represents the stars, 0:11:15.880 --> 0:11:17.880 very much like those tents that had the holes pin 0:11:17.920 --> 0:11:20.880 break through the tent canvas, right right. You know, of 0:11:20.920 --> 0:11:24.280 course this depends on either in this case probably electric 0:11:24.440 --> 0:11:26.720 lights outside or in the case of those tents, having 0:11:26.760 --> 0:11:29.120 a good source of sunlight in order to see what's 0:11:29.120 --> 0:11:32.520 going on. Um. But by the way, a couple of 0:11:32.520 --> 0:11:34.839 distinctions that I wanted to make here. If you've ever 0:11:34.840 --> 0:11:38.160 heard of an ory um, that's that's a physical model 0:11:38.200 --> 0:11:41.240 of the planets in our Solar system, and sometimes also 0:11:41.800 --> 0:11:47.240 called a planetarium, and they're also sometimes included in planetariums. 0:11:47.240 --> 0:11:50.679 So that's nice and confusing, right, So orris are if 0:11:50.720 --> 0:11:52.839 you've ever seen one of those physical models where you've 0:11:52.880 --> 0:11:54.320 got the Sun in the center and then you have 0:11:54.360 --> 0:11:56.720 all the different planets that can spin around the Sun. 0:11:57.040 --> 0:12:01.000 Sometimes they are actually mounted on gears or motors so 0:12:01.040 --> 0:12:04.600 that it represents the accurate movement of each of these 0:12:04.640 --> 0:12:07.920 bodies as they would move in relation to one another. 0:12:08.200 --> 0:12:11.360 So for example, the Earth's uh, the Earth's movement around 0:12:11.400 --> 0:12:14.080 the Sun is different from Saint Mars, which is different 0:12:14.120 --> 0:12:17.080 from Neptune or Saturn. Anyway, you would be able to 0:12:17.120 --> 0:12:19.720 watch these and see how they move in relation to 0:12:19.760 --> 0:12:22.520 each other, see the times when they happen to aligne 0:12:22.600 --> 0:12:26.520 when they get out of alignment, and it's really fascinating 0:12:26.640 --> 0:12:29.839 to see an orry but it's from an outside perspective. 0:12:29.840 --> 0:12:32.280 You're not looking from the inside out. You're looking as 0:12:32.320 --> 0:12:34.920 if you were able to distance yourself all the way 0:12:34.960 --> 0:12:37.600 out of the solar system and look in on it, right, 0:12:37.720 --> 0:12:40.800 and and being that especially early ones, where were you know, 0:12:40.840 --> 0:12:42.960 the planets were all on their little rods and would 0:12:42.960 --> 0:12:46.000 all be going on a on a single plane around 0:12:46.000 --> 0:12:48.280 the Sun rather than in the truth three dimensions in 0:12:48.320 --> 0:12:50.439 which right right it would be. It would be as 0:12:50.440 --> 0:12:53.360 if we had a completely flat solar system, which is 0:12:53.360 --> 0:12:55.960 not exactly true. Yeah, it's like Star Trek World. Everything 0:12:56.000 --> 0:12:58.120 just comes right knows up to each other. Yeah. And 0:12:58.160 --> 0:13:00.840 also they would move in and essentially perfect circles. They 0:13:00.840 --> 0:13:03.360 wouldn't have these kind of elliptical orbitals because that's really 0:13:03.360 --> 0:13:06.720 hard to do with physical rod. But you know, my 0:13:06.840 --> 0:13:09.520 favorite or y of all time is from the movie 0:13:09.520 --> 0:13:12.160 The Dark Crystal, and it's what Augra had. Now that 0:13:12.240 --> 0:13:16.160 of course was an ory for a fictional solar system, 0:13:16.280 --> 0:13:20.200 but was amazing an enormous things spinning around all over 0:13:20.280 --> 0:13:22.760 the place that that lady still creeps me out as 0:13:22.840 --> 0:13:26.920 an incredible movie that everyone should go see. Uh oh, absolutely, yes, 0:13:27.040 --> 0:13:33.840 very much. So I can't okay, science. Besides planetariums and 0:13:34.000 --> 0:13:36.400 uh and or planetaria if we want to talk about 0:13:36.480 --> 0:13:41.200 or reas in that sense, and these globes, we also 0:13:41.280 --> 0:13:45.560 have the concept of keeping track of astronomical phenomena in 0:13:45.640 --> 0:13:49.000 other ways that aren't again all immersive. All right, Well, 0:13:49.040 --> 0:13:53.240 part of the function of a planetarium is as an 0:13:53.280 --> 0:13:56.640 astronomical clock, right, like you were saying earlier, being able 0:13:56.679 --> 0:13:58.599 to to go into the future, into the past and 0:13:58.640 --> 0:14:00.960 see what the stars looked like at any even point. Um. 0:14:01.080 --> 0:14:04.200 And you and Joe talked about a really famous one 0:14:05.080 --> 0:14:09.840 antiquathera device or antiquathera mechanism, which is a some people 0:14:09.840 --> 0:14:14.120 would call the oldest computer and analog computer, and yeah 0:14:14.120 --> 0:14:16.719 and forward thinking. We did a podcast now I think 0:14:16.760 --> 0:14:18.439 I think you did it on tech Stuff. It was 0:14:20.000 --> 0:14:23.160 that's see here's the things that I do. Too many 0:14:23.160 --> 0:14:25.720 shows for too many different different versions. Yes, we did 0:14:25.760 --> 0:14:28.680 do the tech stuff one, so as a reminder because 0:14:28.720 --> 0:14:32.960 obviously I need one. Uh. The Antiquathera device was this, uh, 0:14:33.040 --> 0:14:37.400 this gadget that had been lost in a shipwreck and 0:14:38.080 --> 0:14:40.640 recovered by sponge divers, and it was recovered in very 0:14:40.680 --> 0:14:42.880 poor repair. It was all these different pieces and some 0:14:42.960 --> 0:14:46.560 of them were big chunks and some were smaller pieces. Uh. 0:14:46.600 --> 0:14:49.400 And eventually it took decades to do this, but eventually 0:14:49.480 --> 0:14:52.440 we figured out that this was an astronomical computer. It 0:14:52.520 --> 0:14:56.480 was able to show where the position of the planets 0:14:56.480 --> 0:14:59.520 were in relation to the Earth on any given date, 0:14:59.680 --> 0:15:02.280 in in the position and phase of the moon and 0:15:02.280 --> 0:15:04.760 the position of the Sun, and you would turn a 0:15:04.880 --> 0:15:09.640 crank in order to adjust the dials so that you 0:15:09.680 --> 0:15:13.000 could change it to any date and see what what 0:15:13.040 --> 0:15:16.000 the that actual alignment happened to be on that given date. 0:15:16.040 --> 0:15:18.560 It was also very useful for things like planning out 0:15:18.880 --> 0:15:22.360 specific events because you could do this and find out 0:15:22.360 --> 0:15:24.600 when there was going to be an eclipse, for example, 0:15:25.000 --> 0:15:27.880 and an eclipse tended to be considered a bad omen, 0:15:28.280 --> 0:15:31.640 so you might think, hey, this big festival, we want 0:15:31.680 --> 0:15:33.680 to have what happen to fall on in the eclipse, 0:15:33.720 --> 0:15:37.840 So we're going to have a special a special festival 0:15:37.880 --> 0:15:40.000 that's going to be three weeks earlier so that we 0:15:40.040 --> 0:15:43.000 don't have to worry about that, or an Olympics event 0:15:43.080 --> 0:15:47.600 that there would be another example. So it's really super cool. However, again, 0:15:47.640 --> 0:15:51.880 this was something that was relatively small. We're talking about 0:15:51.960 --> 0:15:54.560 like the size of a large book, and so you're 0:15:54.600 --> 0:15:57.680 looking at at these dials rather than again being immersed 0:15:57.720 --> 0:16:00.680 in the experience. But it was really useful for checking out, 0:16:01.080 --> 0:16:03.920 you know, what a a planetary alignment would be on 0:16:03.920 --> 0:16:08.080 any given date, because again they understood that the movements 0:16:08.080 --> 0:16:11.600 of the planets were regular and cyclical. Yeah, and so 0:16:11.680 --> 0:16:14.200 they were able to do this, and I don't want 0:16:14.240 --> 0:16:18.080 to minimize how difficult this was. They had to build 0:16:18.160 --> 0:16:22.760 exact gear ratios to represent the movement of all these 0:16:22.800 --> 0:16:27.280 planets and sometimes hand machining those. Yeah, yeah, yeah, an 0:16:27.320 --> 0:16:30.000 incredible amount of precision is required, and sometimes you know, 0:16:30.000 --> 0:16:31.920 you would have to have things move backwards a little 0:16:31.920 --> 0:16:35.320 bit and then move forwards because from our perspective, that's 0:16:35.360 --> 0:16:38.200 the way things seem to be moving. So really really 0:16:38.240 --> 0:16:42.320 complicated stuff. Uh but still again that's that's not quite 0:16:42.560 --> 0:16:45.960 an astronomical clock. It's very similar to one. Once we 0:16:46.120 --> 0:16:50.360 looked at actual astronomical clocks. Those look like clocks, but 0:16:50.400 --> 0:16:54.200 they happen to have either a dial or sometimes it's 0:16:54.240 --> 0:16:57.680 a uh, you know, a little physical representation of what 0:16:58.120 --> 0:17:00.080 the planetary alignments are going to be, or the it 0:17:00.160 --> 0:17:02.760 those phase the moon or whatever. These have been popular 0:17:02.800 --> 0:17:05.600 since the middle ages. There were also some of those 0:17:05.680 --> 0:17:08.720 posh sky globes that could hypothetically predict the movement of 0:17:08.760 --> 0:17:11.280 celestial bodies, and Archimedes is said to have had one 0:17:11.400 --> 0:17:17.040 background two right, so uh probably true. Loss of stuff 0:17:17.080 --> 0:17:21.560 about that time period difficult for us to verify, but 0:17:21.560 --> 0:17:24.760 but I'm willing to believe it because they were wicked smart. 0:17:25.240 --> 0:17:28.920 So uh yeah, yeah, Again, we're still talking about stuff 0:17:28.920 --> 0:17:31.080 that lets you look at it. It doesn't surround you 0:17:31.160 --> 0:17:34.520 like the crazy um the globes where you would walk 0:17:34.560 --> 0:17:37.239 inside and take a seat. But that's what leads us 0:17:37.280 --> 0:17:44.120 to the more modern day planetarium that would require projection, yes, 0:17:44.359 --> 0:17:46.800 and not not like standing in the middle and projecting 0:17:46.800 --> 0:17:51.400 out by speaking more loudly. We're talking about light projection here. Yeah, 0:17:51.440 --> 0:17:54.639 but before we get into that, Hey, Jonathan, do you 0:17:54.680 --> 0:17:56.800 think it's about time for us to take a quick 0:17:56.840 --> 0:17:59.160 break for a word from our sponsors. That would be 0:17:59.320 --> 0:18:05.679 an excellent notion. Okay, So projectors planetarium all right. The 0:18:05.760 --> 0:18:08.800 first one was installed in a roof on a rooftop 0:18:08.840 --> 0:18:12.400 in Jenna, Germany, and I apologize, I suppose it would 0:18:12.440 --> 0:18:16.040 it be Jenna, Germany. The j is generally pronounced like 0:18:16.080 --> 0:18:22.439 a y. Well, Jacob would be Yacob Johan, I I 0:18:22.480 --> 0:18:26.520 see where you're going, and I'm guessing it's Jenna. Any 0:18:26.560 --> 0:18:29.920 of our German listeners who would like to to reprimand 0:18:29.960 --> 0:18:33.440 me on my pronunciation feel free, because um I should 0:18:33.560 --> 0:18:36.360 know better at this point. But it was an optical projector, 0:18:36.480 --> 0:18:39.560 so it actually used light and lenses to project images 0:18:39.560 --> 0:18:44.040 of stars on a curved surface the inside of a dome. Yeah. 0:18:44.440 --> 0:18:48.199 So this dates all the way back to nine for 0:18:48.240 --> 0:18:51.080 the earliest of the plans. That's when a man named 0:18:51.080 --> 0:18:55.040 Oscar von Miller commissioned the device for the Deutsche Museum 0:18:55.119 --> 0:18:59.560 in Mind. So the idea to actually use projection was 0:19:00.040 --> 0:19:02.840 read upon. In nineteen fourteen, there was this big meeting 0:19:03.280 --> 0:19:07.080 and generally speaking, most people credit an engineer by the 0:19:07.160 --> 0:19:11.159 name of Walter Bousfeld who came up with this idea 0:19:11.240 --> 0:19:14.120 to use a projector. He was working with the company, 0:19:14.200 --> 0:19:17.159 a company called Carl Zeiss, which was an optics company 0:19:17.280 --> 0:19:20.320 still is in fact still is that's that's very true, uh, 0:19:20.359 --> 0:19:23.800 And they decided that they would use this kind of approach. 0:19:23.960 --> 0:19:26.040 They decided that they wanted to use something that was 0:19:26.480 --> 0:19:29.720 fairly new, the idea of a new source of light 0:19:29.920 --> 0:19:32.359 for people at that time. Well, their their original idea 0:19:32.400 --> 0:19:36.600 here was was to use those fancy, newfangled light bulbs 0:19:37.280 --> 0:19:40.240 as instead of a pin prick, instead of having a 0:19:40.240 --> 0:19:42.760 pinhole for for each light source, they wanted to use 0:19:42.800 --> 0:19:45.840 a light bulb for each star. And they very quickly 0:19:45.880 --> 0:19:50.000 realized how complex and expensive and terrifying that would be, 0:19:50.119 --> 0:19:52.800 especially if you want to be able to move your 0:19:52.840 --> 0:19:55.200 field of vision right right, So if you had all 0:19:55.240 --> 0:19:57.919 these stars in fixed positions on the dome, how do 0:19:57.960 --> 0:20:00.160 you move them if you want to? If you want 0:20:00.160 --> 0:20:02.440 to move the entire ceiling, and that's that's not good. 0:20:02.480 --> 0:20:05.280 Can you imagine the heat generated from those old bulbs 0:20:05.280 --> 0:20:08.000 to all of those things? So this this one engineer, 0:20:08.080 --> 0:20:12.280 Vaulter uh supposedly said, hey, why don't we put the 0:20:12.359 --> 0:20:14.880 light in the middle and then shine it out on 0:20:14.920 --> 0:20:17.760 the on the on the inside, as opposed to poking 0:20:17.760 --> 0:20:19.880 holes on the inside and putting these light bulbs through. 0:20:20.440 --> 0:20:24.679 And people said, you're crazy, except for another engineer, and 0:20:24.760 --> 0:20:27.440 this one. This is a very interesting and tragic story. 0:20:27.480 --> 0:20:29.680 There's actually a really good documentary that we'll talk about. 0:20:29.720 --> 0:20:33.800 But there's an engineer, a scientist, an engineer named Rudolph Straubel, 0:20:34.280 --> 0:20:37.800 who expanded upon Bauersfeld's suggestion. He actually said, wait, this 0:20:37.880 --> 0:20:40.040 is a great idea. We can use a projector and 0:20:40.080 --> 0:20:43.240 not only can the projector show things like the the 0:20:43.280 --> 0:20:45.240 position of planets, which was that that was kind of 0:20:45.280 --> 0:20:47.880 the initial approach was, well, we can show the planets 0:20:47.880 --> 0:20:50.040 this way, so no, we can actually show the stars 0:20:50.040 --> 0:20:52.560 this way too. We don't have to just rely on 0:20:52.640 --> 0:20:54.920 this as being a way of showing the planets. And 0:20:54.960 --> 0:20:57.800 they all began to work on this. Now Strawble would 0:20:57.800 --> 0:21:02.439 eventually leave the museum and this his position working on 0:21:02.480 --> 0:21:06.439 this project because he refused to divorce his Jewish wife. 0:21:07.040 --> 0:21:09.800 So this was the rise of the the Nazis in 0:21:09.880 --> 0:21:13.200 Germany at the time. And um, there's a documentary called 0:21:13.240 --> 0:21:18.800 Planetarium that really follows this and the the general perspective 0:21:18.800 --> 0:21:22.680 on Planetarium is that Strawble was actually a major contributor 0:21:22.840 --> 0:21:26.600 to uh to this first planetarium, but his work was 0:21:26.680 --> 0:21:30.000 all but erased by the Nazis, and then the Nazis 0:21:30.560 --> 0:21:34.840 attempts to erase it were then subsequently erased, partly because 0:21:35.240 --> 0:21:38.680 the the company, the Zeiss Company, got split into two 0:21:38.680 --> 0:21:41.159 companies after World War Two. Half of it was in 0:21:41.160 --> 0:21:43.760 the East Germany, the other half in West Germany and 0:21:43.840 --> 0:21:47.120 too for the West Germany side to uh, to talk 0:21:47.200 --> 0:21:50.680 about strawble would have also been to admit that they 0:21:50.720 --> 0:21:55.560 had bowed to the Nazis uh demands, and so it 0:21:55.640 --> 0:22:00.280 was not politically, uh, let's see what's the right way student, 0:22:00.760 --> 0:22:03.840 it was not prudent at that at that juncture, so 0:22:03.920 --> 0:22:07.080 to speak, to make that admission. So if you're really 0:22:07.119 --> 0:22:10.360 interested to hear more about the the drama behind that 0:22:10.440 --> 0:22:14.560 and also the truly the tragedy behind that story, check 0:22:14.560 --> 0:22:17.840 out the documentary Planetarium at anyway, getting back to the 0:22:17.840 --> 0:22:21.480 planetarium itself, it took years of research and development before 0:22:21.480 --> 0:22:25.239 construction could begin. Right. Also they were there was a 0:22:25.280 --> 0:22:28.600