Speaker 1: Get in touch with technology. What's tech stuff from dot com?
Speaker 1: Hey there, and welcome to tech stuff. I'm Jonathan Strickland
Speaker 1: and I'm Lauren Fock Obama. And we thought today we
Speaker 1: would do a little star gazing. But we're not out
Speaker 1: doorsy types. Lauren. Uh, well, I mean we can be,
Speaker 1: but actually at night it's more or less fun. Yeah,
Speaker 1: it's really the sun gets us. But but anyway, sometimes
Speaker 1: sometimes you're just not able to really do some good
Speaker 1: star gazing depending upon where you are. Maybe it's overcast,
Speaker 1: or maybe there are other conditions will talk about that
Speaker 1: kind of prevents you from doing it. So where do
Speaker 1: you go for star gazing when the stars are not
Speaker 1: necessarily visible to you at that particular moment. Planetarium would
Speaker 1: be a pretty good option. Yes, it is not pronounced
Speaker 1: as Matt Frederick would say, as a planet arium. It's
Speaker 1: a planetarium which is essentially uh in enclosed with an
Speaker 1: artificial sky that has stars and sometimes plants and sometimes
Speaker 1: other celestial bodies represented some kind of space scape. Yeah.
Speaker 1: So there are a lot of different types of planetariums
Speaker 1: that all use a very similar approach, but you know,
Speaker 1: the actual implementation can differ between one and the other.
Speaker 1: But we wanted to talk more about all of the
Speaker 1: kind of history that built into coming up to the
Speaker 1: planetariums as well as how they actually work. Right. We
Speaker 1: didn't want to just explain it's a projector and then
Speaker 1: go in from there. I mean, because because basically it's
Speaker 1: a projector. Yea, So we could just say it's a projector,
Speaker 1: and if you know how a projector, it's a Friday,
Speaker 1: so we're ready to go home. But no, we wanted
Speaker 1: to actually talk about the history of planetariums because it's
Speaker 1: a fascinating story. I mean, obviously, as as a species,
Speaker 1: humans have been fascinated with the heavens since before recorded history.
Speaker 1: I mean, this is something that we've obviously been really
Speaker 1: amazed by over thousands of years. It's pretty amazing. And
Speaker 1: what's interesting is that there have been lots of different
Speaker 1: attempts to create a an indoor version of this experience,
Speaker 1: because it's not always convenient to go outside and do
Speaker 1: all your your work. And based upon thousands of years
Speaker 1: of observations, we got pretty good at figure out how
Speaker 1: to represent the night sky in a way that was
Speaker 1: accurate even with the movement of things like planets in
Speaker 1: the moon and the Sun and Earth itself. Yeah, I
Speaker 1: mean it took us a while to figure that part out,
Speaker 1: that the Earth itself was moving and not say everything
Speaker 1: else was moving around the Earth. And depending upon whom
Speaker 1: you are, you might still argue that thinking of a
Speaker 1: specific documentary that Jane Way was the voice for anyway. So,
Speaker 1: assuming you're not having this geocentric view, even even that
Speaker 1: would allow you to see that the the heavens move
Speaker 1: in a very pretty actable way. It may take a
Speaker 1: long time for a particular cycle to happen, but once
Speaker 1: you know what those cycles are, you could predict make
Speaker 1: observations that would end up either verifying or or negating
Speaker 1: the previous guesswork, and eventually you make it into a science.
Speaker 1: So why our planetariums themselves awesome? Well, for one, you
Speaker 1: get to look at the stars, even if again you
Speaker 1: are in a place where you can't normally see them,
Speaker 1: like here in Atlanta, we get a lot of what's
Speaker 1: called light pollution. So that's just a you know, any
Speaker 1: major city tends to have this where you've got lots
Speaker 1: of lights that are on at night, and that tends
Speaker 1: to drown out some of the stars. You can't see
Speaker 1: the fainter ones. You really only see the brightest ones
Speaker 1: that are in the sky. Uh. You know, you might
Speaker 1: be able to see things like Venus, which are that's
Speaker 1: that's extremely bright, and you might see some of the
Speaker 1: major stars and some of the major constellations, but you're
Speaker 1: missing out on a lot certainly. So unless you go
Speaker 1: way out into the middle of no Aware where there
Speaker 1: aren't so many lights, or you have to live someplace
Speaker 1: that has really strict rules about the lights at night.
Speaker 1: Because there are a few of those places, you probably
Speaker 1: can't see that many. And even in those places it
Speaker 1: sometimes rains or gets cloudy. It turns out clouds really
Speaker 1: inhibit the star gazing activities. Also, the sky over the
Speaker 1: Southern Hemisphere is different than that over the Northern Hemisphere. So, um,
Speaker 1: if if you don't travel back and forth pretty frequently
Speaker 1: between the two, Yeah, if you don't cross the line
Speaker 1: over at the equator and shout out to all my
Speaker 1: navy buddies who do um, if you don't do that frequently, yeah,
Speaker 1: you know, you miss out on the way the sky
Speaker 1: looks and in the Southern hemisphere, or if you live
Speaker 1: in the Southern hemisphere the Northern hemisphere, so I'll fly
Speaker 1: to our New Zealand listeners. There's a lot of you.
Speaker 1: There's actually quite a few of you. UM. I will
Speaker 1: not confuse you with the Australian listeners, please don't we
Speaker 1: We love all of you equally. So if you've never
Speaker 1: been there, but you want to see what the sky
Speaker 1: looks like up Manitarium, some of them, anyway, can accommodate you.
Speaker 1: A lot of them have the capability of showing the
Speaker 1: stars over any particular point on Earth. Like That's how
Speaker 1: sophisticated they've become. So not only that, but they many
Speaker 1: of them can also show you what the sky would
Speaker 1: look like on any given date. So you might say, well,
Speaker 1: what did the sky look like yesterday? What will it
Speaker 1: look like tomorrow? What will it look like in a century?
Speaker 1: What will it look like a hundred centuries from now?
Speaker 1: What did it look like back in the day that
Speaker 1: Shakespeare wrote his plays? Like, you could do any of
Speaker 1: those things, and by plugging in some some numbers. The
Speaker 1: computers that handle the calculations for most of these uh devices,
Speaker 1: not all of them, some of them are a little older,
Speaker 1: but most of them can take that into consideration and
Speaker 1: actually determine what the position of the planets would be
Speaker 1: on any given date, the stars, etcetera, which is pretty awesome. Yeah. Um,
Speaker 1: they can also be used to teach celestial navigation, and
Speaker 1: they certainly were used for that purpose during World War two.
Speaker 1: Very useful, especially if you can't always depend upon instruments
Speaker 1: to be able to get around. Also, hey, it teaches astronomy. Yeah,
Speaker 1: you know, I always almost left that out of the notes,
Speaker 1: and I was like, yeah, that's a that's a big deal.
Speaker 1: I guess that's the thing. Yeah. So obviously the astronomers
Speaker 1: out there if you want to be able to identify
Speaker 1: various star clusters things like that, and a lot of
Speaker 1: these have special um projectors that will show things like
Speaker 1: the Milky Way galaxy or other nebula or things like that.
Speaker 1: And that's important. Oh sure, sure, but we will get
Speaker 1: into that later on. Um, let's talk for right now
Speaker 1: about the history of these devices, because people have been
Speaker 1: painting the sky on ceilings I mean for for basically ever. Yeah,
Speaker 1: I mean, like I got a cousin who has the
Speaker 1: Glow in the Dark ones that's been on her her
Speaker 1: bedroom ceiling like since she was like four. So yeah. Also,
Speaker 1: there's a star map on the ceiling of the tomb
Speaker 1: of the Egyptian official sinement that dates from that does
Speaker 1: predate my cousin, so a little bit your your argument
Speaker 1: is valid. Yeah, I mean this is something, like I said,
Speaker 1: humans have been fascinated with the stars for as long
Speaker 1: as we've been looking around and being able to express
Speaker 1: our thoughts. So it's no surprise that we're seeing evidence
Speaker 1: of that in in prehistoric and and uh, you know,
Speaker 1: just post historic, fairly historic uh, you know, drawings and
Speaker 1: and uh and depictions on things like this tomb. And
Speaker 1: then we have some early examples of what could be
Speaker 1: something like a planetarium from the Arabic world right right there,
Speaker 1: there were Arabic tents made with holes in the fabric
Speaker 1: to let outside lights shine through, representing each star or
Speaker 1: each star as they knew them. And in that time
Speaker 1: um described in European History Circle that twelve hundreds are
Speaker 1: so and so that's that's you know, that's a good
Speaker 1: while back, right and then we had, uh, let's let's
Speaker 1: switch up to say, oh, I don't know, let's let's
Speaker 1: go to the idea of using globes and sky maps.
Speaker 1: This is really cool too. So starting a couple of
Speaker 1: thousand years ago, it became really popular in the West
Speaker 1: to draw sky maps on globes, and um the first
Speaker 1: planetarium is known to history. Were huge versions of these,
Speaker 1: like big enough for people to sit in. A really
Speaker 1: famous example is the gor Top Globe, supposedly based on
Speaker 1: plans found among Tico Brahe's papers. Okay, so wait, wait, wait,
Speaker 1: Tico Bray. I've always heard Tycho Bray. Where did you
Speaker 1: hear Tico Brian. I'm one of my astronomy professors in
Speaker 1: college called him Tico. That's good enough for me. So
Speaker 1: I know, I know that the Penny Arcade dude calls
Speaker 1: himself Tycho, but hey, we're going with an astronomy professor's approach.
Speaker 1: I'm I'm all right with bowing to authority on this one.
Speaker 1: He had a really impressive beard, so that also, I mean,
Speaker 1: that's like credentials in the astronomy world. So that's totally cool.
Speaker 1: So that that was that was built in the mid
Speaker 1: sixteen hundreds and what's now Germany, and it was large
Speaker 1: enough for like twelve people to sit in on these
Speaker 1: circular benches that were around a table um where refreshments
Speaker 1: could be served. Obviously, um so, so the So the object,
Speaker 1: this globe was about ten ft or three meters in diameter,
Speaker 1: and the stars in it were these gilded, spangled fixtures
Speaker 1: in the inside surface of the globe that we're eliminated
Speaker 1: by a lamp that would sit on the table along
Speaker 1: with your you know, snaky cakes. Interesting. So it's like
Speaker 1: it's like if you look at a regular globe, you know,
Speaker 1: that's something that we look at on the outside surface
Speaker 1: obviously that's you know, representing the Earth. But this is
Speaker 1: one where we would go on the inside and we're
Speaker 1: looking at the inner wall, which is representing the heavens,
Speaker 1: the heavens right right, and the outside of it was
Speaker 1: actually painted like like the Earth. It had all of
Speaker 1: the continents and everything on it. Pretty cool that whole
Speaker 1: globe shell could could rotate around the viewers thanks to
Speaker 1: some water powered machinery. And it took some ten years
Speaker 1: to build and weighs like three tons, despite which it
Speaker 1: was moved to St. Petersburg as a gift to Peter
Speaker 1: the Great in seventeen seventeen. Shortly after that, it was
Speaker 1: partially destroyed in a fire, then restored, then stolen by
Speaker 1: the Germans in World War Two, found by US troops
Speaker 1: and restored again to St. Petersburg. I'm pretty sure that
Speaker 1: should be an Indiana Jones plot. All right, it's great,
Speaker 1: and this thing weighs three tons. It takes some determination
Speaker 1: to steal anything that weighs three tons. That's pretty incredible.
Speaker 1: But so the practice of making these these enterable sky
Speaker 1: globes like this unwieldy as they were persisted into the
Speaker 1: nineteen hundreds. The Museum of the Chicago Academy of Sciences
Speaker 1: built their Atwood globe as late as nine um and
Speaker 1: and that's that's about the same size, a little bigger
Speaker 1: at measure sixteen feet, that's about five meters in diameter
Speaker 1: um and shows six nine two stars plus the planets
Speaker 1: in our solar system, as as holes through which outside
Speaker 1: light can shine. It's electric and the shell can spin
Speaker 1: once every eight minutes around viewers. Interesting, and so this
Speaker 1: is kind of it's it's like it's taking a note
Speaker 1: back from those old Arabic tents, right the lights coming
Speaker 1: from outside shining through holes, and that's what represents the stars,
Speaker 1: very much like those tents that had the holes pin
Speaker 1: break through the tent canvas, right right. You know, of
Speaker 1: course this depends on either in this case probably electric
Speaker 1: lights outside or in the case of those tents, having
Speaker 1: a good source of sunlight in order to see what's
Speaker 1: going on. Um. But by the way, a couple of
Speaker 1: distinctions that I wanted to make here. If you've ever
Speaker 1: heard of an ory um, that's that's a physical model
Speaker 1: of the planets in our Solar system, and sometimes also
Speaker 1: called a planetarium, and they're also sometimes included in planetariums.
Speaker 1: So that's nice and confusing, right, So orris are if
Speaker 1: you've ever seen one of those physical models where you've
Speaker 1: got the Sun in the center and then you have
Speaker 1: all the different planets that can spin around the Sun.
Speaker 1: Sometimes they are actually mounted on gears or motors so
Speaker 1: that it represents the accurate movement of each of these
Speaker 1: bodies as they would move in relation to one another.
Speaker 1: So for example, the Earth's uh, the Earth's movement around
Speaker 1: the Sun is different from Saint Mars, which is different
Speaker 1: from Neptune or Saturn. Anyway, you would be able to
Speaker 1: watch these and see how they move in relation to
Speaker 1: each other, see the times when they happen to aligne
Speaker 1: when they get out of alignment, and it's really fascinating
Speaker 1: to see an orry but it's from an outside perspective.
Speaker 1: You're not looking from the inside out. You're looking as
Speaker 1: if you were able to distance yourself all the way
Speaker 1: out of the solar system and look in on it, right,
Speaker 1: and and being that especially early ones, where were you know,
Speaker 1: the planets were all on their little rods and would
Speaker 1: all be going on a on a single plane around
Speaker 1: the Sun rather than in the truth three dimensions in
Speaker 1: which right right it would be. It would be as
Speaker 1: if we had a completely flat solar system, which is
Speaker 1: not exactly true. Yeah, it's like Star Trek World. Everything
Speaker 1: just comes right knows up to each other. Yeah. And
Speaker 1: also they would move in and essentially perfect circles. They
Speaker 1: wouldn't have these kind of elliptical orbitals because that's really
Speaker 1: hard to do with physical rod. But you know, my
Speaker 1: favorite or y of all time is from the movie
Speaker 1: The Dark Crystal, and it's what Augra had. Now that
Speaker 1: of course was an ory for a fictional solar system,
Speaker 1: but was amazing an enormous things spinning around all over
Speaker 1: the place that that lady still creeps me out as
Speaker 1: an incredible movie that everyone should go see. Uh oh, absolutely, yes,
Speaker 1: very much. So I can't okay, science. Besides planetariums and
Speaker 1: uh and or planetaria if we want to talk about
Speaker 1: or reas in that sense, and these globes, we also
Speaker 1: have the concept of keeping track of astronomical phenomena in
Speaker 1: other ways that aren't again all immersive. All right, Well,
Speaker 1: part of the function of a planetarium is as an
Speaker 1: astronomical clock, right, like you were saying earlier, being able
Speaker 1: to to go into the future, into the past and
Speaker 1: see what the stars looked like at any even point. Um.
Speaker 1: And you and Joe talked about a really famous one
Speaker 1: antiquathera device or antiquathera mechanism, which is a some people
Speaker 1: would call the oldest computer and analog computer, and yeah
Speaker 1: and forward thinking. We did a podcast now I think
Speaker 1: I think you did it on tech Stuff. It was
Speaker 1: that's see here's the things that I do. Too many
Speaker 1: shows for too many different different versions. Yes, we did
Speaker 1: do the tech stuff one, so as a reminder because
Speaker 1: obviously I need one. Uh. The Antiquathera device was this, uh,
Speaker 1: this gadget that had been lost in a shipwreck and
Speaker 1: recovered by sponge divers, and it was recovered in very
Speaker 1: poor repair. It was all these different pieces and some
Speaker 1: of them were big chunks and some were smaller pieces. Uh.
Speaker 1: And eventually it took decades to do this, but eventually
Speaker 1: we figured out that this was an astronomical computer. It
Speaker 1: was able to show where the position of the planets
Speaker 1: were in relation to the Earth on any given date,
Speaker 1: in in the position and phase of the moon and
Speaker 1: the position of the Sun, and you would turn a
Speaker 1: crank in order to adjust the dials so that you
Speaker 1: could change it to any date and see what what
Speaker 1: the that actual alignment happened to be on that given date.
Speaker 1: It was also very useful for things like planning out
Speaker 1: specific events because you could do this and find out
Speaker 1: when there was going to be an eclipse, for example,
Speaker 1: and an eclipse tended to be considered a bad omen,
Speaker 1: so you might think, hey, this big festival, we want
Speaker 1: to have what happen to fall on in the eclipse,
Speaker 1: So we're going to have a special a special festival
Speaker 1: that's going to be three weeks earlier so that we
Speaker 1: don't have to worry about that, or an Olympics event
Speaker 1: that there would be another example. So it's really super cool. However, again,
Speaker 1: this was something that was relatively small. We're talking about
Speaker 1: like the size of a large book, and so you're
Speaker 1: looking at at these dials rather than again being immersed
Speaker 1: in the experience. But it was really useful for checking out,
Speaker 1: you know, what a a planetary alignment would be on
Speaker 1: any given date, because again they understood that the movements
Speaker 1: of the planets were regular and cyclical. Yeah, and so
Speaker 1: they were able to do this, and I don't want
Speaker 1: to minimize how difficult this was. They had to build
Speaker 1: exact gear ratios to represent the movement of all these
Speaker 1: planets and sometimes hand machining those. Yeah, yeah, yeah, an
Speaker 1: incredible amount of precision is required, and sometimes you know,
Speaker 1: you would have to have things move backwards a little
Speaker 1: bit and then move forwards because from our perspective, that's
Speaker 1: the way things seem to be moving. So really really
Speaker 1: complicated stuff. Uh but still again that's that's not quite
Speaker 1: an astronomical clock. It's very similar to one. Once we
Speaker 1: looked at actual astronomical clocks. Those look like clocks, but
Speaker 1: they happen to have either a dial or sometimes it's
Speaker 1: a uh, you know, a little physical representation of what
Speaker 1: the planetary alignments are going to be, or the it
Speaker 1: those phase the moon or whatever. These have been popular
Speaker 1: since the middle ages. There were also some of those
Speaker 1: posh sky globes that could hypothetically predict the movement of
Speaker 1: celestial bodies, and Archimedes is said to have had one
Speaker 1: background two right, so uh probably true. Loss of stuff
Speaker 1: about that time period difficult for us to verify, but
Speaker 1: but I'm willing to believe it because they were wicked smart.
Speaker 1: So uh yeah, yeah, Again, we're still talking about stuff
Speaker 1: that lets you look at it. It doesn't surround you
Speaker 1: like the crazy um the globes where you would walk
Speaker 1: inside and take a seat. But that's what leads us
Speaker 1: to the more modern day planetarium that would require projection, yes,
Speaker 1: and not not like standing in the middle and projecting
Speaker 1: out by speaking more loudly. We're talking about light projection here. Yeah,
Speaker 1: but before we get into that, Hey, Jonathan, do you
Speaker 1: think it's about time for us to take a quick
Speaker 1: break for a word from our sponsors. That would be
Speaker 1: an excellent notion. Okay, So projectors planetarium all right. The
Speaker 1: first one was installed in a roof on a rooftop
Speaker 1: in Jenna, Germany, and I apologize, I suppose it would
Speaker 1: it be Jenna, Germany. The j is generally pronounced like
Speaker 1: a y. Well, Jacob would be Yacob Johan, I I
Speaker 1: see where you're going, and I'm guessing it's Jenna. Any
Speaker 1: of our German listeners who would like to to reprimand
Speaker 1: me on my pronunciation feel free, because um I should
Speaker 1: know better at this point. But it was an optical projector,
Speaker 1: so it actually used light and lenses to project images
Speaker 1: of stars on a curved surface the inside of a dome. Yeah.
Speaker 1: So this dates all the way back to nine for
Speaker 1: the earliest of the plans. That's when a man named
Speaker 1: Oscar von Miller commissioned the device for the Deutsche Museum
Speaker 1: in Mind. So the idea to actually use projection was
Speaker 1: read upon. In nineteen fourteen, there was this big meeting
Speaker 1: and generally speaking, most people credit an engineer by the
Speaker 1: name of Walter Bousfeld who came up with this idea
Speaker 1: to use a projector. He was working with the company,
Speaker 1: a company called Carl Zeiss, which was an optics company
Speaker 1: still is in fact still is that's that's very true, uh,
Speaker 1: And they decided that they would use this kind of approach.
Speaker 1: They decided that they wanted to use something that was
Speaker 1: fairly new, the idea of a new source of light
Speaker 1: for people at that time. Well, their their original idea
Speaker 1: here was was to use those fancy, newfangled light bulbs
Speaker 1: as instead of a pin prick, instead of having a
Speaker 1: pinhole for for each light source, they wanted to use
Speaker 1: a light bulb for each star. And they very quickly
Speaker 1: realized how complex and expensive and terrifying that would be,
Speaker 1: especially if you want to be able to move your
Speaker 1: field of vision right right, So if you had all
Speaker 1: these stars in fixed positions on the dome, how do
Speaker 1: you move them if you want to? If you want
Speaker 1: to move the entire ceiling, and that's that's not good.
Speaker 1: Can you imagine the heat generated from those old bulbs
Speaker 1: to all of those things? So this this one engineer,
Speaker 1: Vaulter uh supposedly said, hey, why don't we put the
Speaker 1: light in the middle and then shine it out on
Speaker 1: the on the on the inside, as opposed to poking
Speaker 1: holes on the inside and putting these light bulbs through.
Speaker 1: And people said, you're crazy, except for another engineer, and
Speaker 1: this one. This is a very interesting and tragic story.
Speaker 1: There's actually a really good documentary that we'll talk about.
Speaker 1: But there's an engineer, a scientist, an engineer named Rudolph Straubel,
Speaker 1: who expanded upon Bauersfeld's suggestion. He actually said, wait, this
Speaker 1: is a great idea. We can use a projector and
Speaker 1: not only can the projector show things like the the
Speaker 1: position of planets, which was that that was kind of
Speaker 1: the initial approach was, well, we can show the planets
Speaker 1: this way, so no, we can actually show the stars
Speaker 1: this way too. We don't have to just rely on
Speaker 1: this as being a way of showing the planets. And
Speaker 1: they all began to work on this. Now Strawble would
Speaker 1: eventually leave the museum and this his position working on
Speaker 1: this project because he refused to divorce his Jewish wife.
Speaker 1: So this was the rise of the the Nazis in
Speaker 1: Germany at the time. And um, there's a documentary called
Speaker 1: Planetarium that really follows this and the the general perspective
Speaker 1: on Planetarium is that Strawble was actually a major contributor
Speaker 1: to uh to this first planetarium, but his work was
Speaker 1: all but erased by the Nazis, and then the Nazis
Speaker 1: attempts to erase it were then subsequently erased, partly because
Speaker 1: the the company, the Zeiss Company, got split into two
Speaker 1: companies after World War Two. Half of it was in
Speaker 1: the East Germany, the other half in West Germany and
Speaker 1: too for the West Germany side to uh, to talk
Speaker 1: about strawble would have also been to admit that they
Speaker 1: had bowed to the Nazis uh demands, and so it
Speaker 1: was not politically, uh, let's see what's the right way student,
Speaker 1: it was not prudent at that at that juncture, so
Speaker 1: to speak, to make that admission. So if you're really
Speaker 1: interested to hear more about the the drama behind that
Speaker 1: and also the truly the tragedy behind that story, check
Speaker 1: out the documentary Planetarium at anyway, getting back to the
Speaker 1: planetarium itself, it took years of research and development before
Speaker 1: construction could begin. Right. Also they were there was a
Speaker 1: war from from yeah, there was World War One, yeah,
Speaker 1: and then and then the nineteen yeah, so that we
Speaker 1: had World War one going, so that that puts things
Speaker 1: on hold. Construction will begin in nineteen nineteen. It wouldn't
Speaker 1: be completed until nineteen twenty three and was first shown
Speaker 1: on a rooftop in Yana, Germany, and then would eventually
Speaker 1: move to its permanent home in the Deutsche Museum in
Speaker 1: n And this had what was called a star ball.
Speaker 1: A star ball this is this is a perforated sphere
Speaker 1: that that powerful light can be shown through up onto
Speaker 1: the dome like like we've been talking about um by
Speaker 1: By Around a decade later, domes like this would be
Speaker 1: installed in museums around the world, especially after affordability improvements
Speaker 1: were made to the Zeist device by Armand's fits in
Speaker 1: six He was then the director of the Franklin Institute
Speaker 1: in Philadelphia, and he his innovation was to um to
Speaker 1: scale it down from from a starball to a star dodecahedron.
Speaker 1: Ah yeah, okay, that makes sense. You get a lot
Speaker 1: more flat surfaces. Flat surfaces, it's easier to to machine
Speaker 1: in those days. A sphere is not easy. No, no, Um.
Speaker 1: It was actually suggested to him by Einstein. The story
Speaker 1: goes way to go Einstein, all right, So yeah, UM
Speaker 1: circle of the nineteen sixties lenses would come in to
Speaker 1: use to amplify the appearance of brighter stars to make
Speaker 1: a more realistic starfield and more expensive machines. Around the
Speaker 1: same time, multiple projectors, each with their own star plates.
Speaker 1: UM would let you use lights of different brightnesses to
Speaker 1: project different magnitudes of stars. Gotcha. So yeah, it gets
Speaker 1: a little tricky, like how do you represent the stars
Speaker 1: accurately because some, of course when you look up in
Speaker 1: the sky, are much brighter than others. And there's only
Speaker 1: so much you can do with with machining, different different
Speaker 1: apertures of pin pricks, right right, So yeah, it was
Speaker 1: pretty complicated stuff. So how do they work today? Well,
Speaker 1: if you were to go to the one in the
Speaker 1: Deutsche Museum, it's been updated several times over the course
Speaker 1: of its history, so it's not the same device that
Speaker 1: was installed back in No, it's had some eight million
Speaker 1: visitors or more over the intervening years. And now they
Speaker 1: use a projector that has thirty two different slides to
Speaker 1: create the images of stars and planets on the curve
Speaker 1: surface of the walls and ceiling. Now these slides have
Speaker 1: a fine pattern of holes that correspond to the actual
Speaker 1: position of stars in the night sky above Germany. It's
Speaker 1: specific to that. Yeah, I mean it would be weird
Speaker 1: for them to have a representation of the sky above
Speaker 1: somewhere else. I mean, this is this is you know
Speaker 1: above where the facility is. Each slide is a pair
Speaker 1: of glass panes, you know, like a slide, you know,
Speaker 1: the juicier a microscope or something between these pains. There's
Speaker 1: a thin layer of copper and they punch holes in
Speaker 1: the copper. Now, the size of the hole determines how
Speaker 1: bright the star is going to be, right, so if
Speaker 1: you make a tiny hole, it's going to be a
Speaker 1: relatively faint star. If you make a larger hole, it's
Speaker 1: gonna be a brighter star. The lenses you used to
Speaker 1: help focus that light so that it's the right size,
Speaker 1: so you've got the right brightness and size. Yep. Yeah,
Speaker 1: you don't want to have just this kind of fuzzy
Speaker 1: blurry effect. So generally speaking, you got a lamp that's
Speaker 1: what's providing the back light, and you have special projectors
Speaker 1: for the sun, Moon, the planets, and the Milky Way
Speaker 1: to complete the picture. So this is a multi projector
Speaker 1: set up. Um. Now, the original structure relied on gears
Speaker 1: to turn the projectors precisely to mimic celestial movements, so
Speaker 1: you would actually of someone manually turning some We have
Speaker 1: sense upgraded. Now it's electric motors that do this. Uh.
Speaker 1: And again you have the gear ratios worked out so
Speaker 1: that they mimic the actual movements. So uh, you know,
Speaker 1: you could just have everything turning. But of course that
Speaker 1: wouldn't be accurate to what we actually see in nature.
Speaker 1: You have to be a little more specific so that
Speaker 1: you know when Mars is going past your vision, it's
Speaker 1: doing so at the right speed relative to the other
Speaker 1: other sites in the sky. So, uh. The neat thing
Speaker 1: about this is that you can actually obviously speed things
Speaker 1: up or slow things down. So you could sit there
Speaker 1: and say, all, right, here's what the path of Mars
Speaker 1: looks like over the course of a month, and you
Speaker 1: could show it in in uh, sped up time, so
Speaker 1: you don't actually have to sit there for a month
Speaker 1: to see it happen, right, Or you can reverse it
Speaker 1: so that you can say, here's what Mars did last month, right,
Speaker 1: And then of course that sets time backward. And then,
Speaker 1: because we learned that from Superman, right, if you spend
Speaker 1: the world backwards, then obviously time reverses. It's okay. They
Speaker 1: all have way back machines in turnums, right, so they
Speaker 1: all everything works out in the end by the time
Speaker 1: you leave, everything's right back to where was, so you
Speaker 1: don't have to mess with your watch. That's that's really smart. Now,
Speaker 1: about six of all planetariums still use projectors like this.
Speaker 1: I get this particular figure from the planetarium in Hilo, Hawaii,
Speaker 1: a lovely place to visit, by the way. So they
Speaker 1: use standard video special mechanical projectors to create those images
Speaker 1: of the night sky. But beginning in the nineteen eighties,
Speaker 1: some planetariums began to experiment with going digital rather than analog.
Speaker 1: It wouldn't be until the nineteen nineties that planetariums could
Speaker 1: actually experiment with full dome animated content. Uh Now, full
Speaker 1: dome animated content this is used for lots of stuff.
Speaker 1: It's not just used for planetariums. For example, there are
Speaker 1: virtual environments that use domes to represent things like say
Speaker 1: the sky for a a jet simulator. So these domes
Speaker 1: allow you to have this amazing field view that you
Speaker 1: can then project some sort of virtual environment on and
Speaker 1: that's more effective than say being in a flat room
Speaker 1: with corners and flat surfaces that doesn't usually convey as
Speaker 1: realistic and experience. So for planetariums it's great because it
Speaker 1: can mimic the night sky very well. Uh Now, this
Speaker 1: this full dome approach meant that you could have some
Speaker 1: really cool effects, but it also comes with some challenges.
Speaker 1: It's not uh always easy to do. If you're using
Speaker 1: a multiprojector approach. For example, you have to make sure
Speaker 1: that all of the edges are going to line up
Speaker 1: with each other so that you don't have any kind
Speaker 1: of wackiness in between, right exactly. Let's so, let's say
Speaker 1: that you have a projector that is a certain like
Speaker 1: if you look at the dome as kind of a
Speaker 1: a pie, so you think of a slice of that pie.
Speaker 1: One projector is responsible for that slice. The next projector
Speaker 1: is responsible for the slice next to that. If those
Speaker 1: two projectors are out of alignment, then you're gonna have
Speaker 1: some stars that are overlapping each other. And then you
Speaker 1: have this added to property of light. You know, you
Speaker 1: have light from two different sources hitting the same physical space,
Speaker 1: and it's gonna be blurry, it's gonna be too bright,
Speaker 1: it's not going to represent the actual stars. So this
Speaker 1: is something that has to be very carefully calibrated every
Speaker 1: single time any maintenance is done on it. So this
Speaker 1: is true for all planetariums. It's not just for the
Speaker 1: ones that are multiprojector, but multiprojector in particular, you have
Speaker 1: to make these considerations. Yeah, they generally still call it
Speaker 1: a star ball. By the way, this kind of a
Speaker 1: spherical construction into which all of these projectors are are
Speaker 1: sat is still called a star ball. I think starball
Speaker 1: is a really great word. Starball just I mean it
Speaker 1: sounds like something out of Cardamri Dominancy to me, which
Speaker 1: I think is why I'm so fond of it. I was,
Speaker 1: I was thinking it sounds like a like like a
Speaker 1: John Carpenter movie, but maybe I'm thinking Starman. So yeah,
Speaker 1: it's um, pretty pretty cool. I mean, obviously, if you
Speaker 1: if you wanna have a planetarium, one of the concerns
Speaker 1: you have is that you wanted to be really dark.
Speaker 1: You don't want to have any kind of other light
Speaker 1: bleeding into it because that's going to interrupt the actual
Speaker 1: view that you want. Um. Also, you know, you could
Speaker 1: go with a single projector, which would be at the
Speaker 1: center of the planetarium. So you've got a projector that's
Speaker 1: right in the very middle. Now, one thing that you
Speaker 1: have to keep in mind, there's a drawback there. You
Speaker 1: can't stand in the middle because that's where the actual
Speaker 1: projector is. These things, by the way, cost lots of money,
Speaker 1: you know, sometimes hundreds of thousands of dollars. So generally speaking,
Speaker 1: if you're in a planetarium that has a single projector,
Speaker 1: there tends to be like railings and things like that
Speaker 1: so that you can't get too close and mess with it.
Speaker 1: I remember standing right next to one for a commercial
Speaker 1: for a science fiction convention back when I was thirteen
Speaker 1: years old, and I would never been more terrified in
Speaker 1: my life that I was going to end up bankrupting
Speaker 1: my parents by by accidentally falling against this planetarium projector.
Speaker 1: But yeah, it's it's uh, it's it's usually blocked off.
Speaker 1: It takes up that center space, So one thing you've
Speaker 1: got to keep in mind is that takes up potential
Speaker 1: place for people to sit. However, sitting in the center
Speaker 1: of a planetarium is rarely the best seat, so usually
Speaker 1: you just you just make use of the outer edge
Speaker 1: as much as you possibly can. But with that center
Speaker 1: single projector, you also don't have to worry about bleeding
Speaker 1: into other projectors. Assuming you've got one that's the master
Speaker 1: projector that handles everything including the planets, the Sun, the moon,
Speaker 1: all that stuff, you're good to go. You don't have
Speaker 1: to worry about that those other issues of are these
Speaker 1: things perfectly aligned, because everything should be fine assuming that
Speaker 1: the projector itself is in good working order. The multi
Speaker 1: projector set ups that that that I was talking about
Speaker 1: a second ago are are in those starballs. But I
Speaker 1: but it sounds like, Jonathan, you're talking about a a
Speaker 1: different kind of projector set up. Yeah, there's actually there
Speaker 1: are different ways you can do this. You can have
Speaker 1: the multi projector all in the center, which is similar
Speaker 1: to that single projector I was just talking about, which
Speaker 1: may or may not have multiple lenses on it. In fact,
Speaker 1: it usually does have multiple lenses on it, so it
Speaker 1: can look a lot like the multi projector set up.
Speaker 1: But there are other mule projector set ups where it
Speaker 1: leaves the center completely clear. And the way they do
Speaker 1: that is they set the projectors up along the inside
Speaker 1: perimeter of this dome and they use mirrors to reflect
Speaker 1: the light from the projectors so that it hits the
Speaker 1: precise spots on the inside of the dome, so you
Speaker 1: get that starry night appear. So, yeah, you know, they're multiple.
Speaker 1: The nice thing is is that once you know the
Speaker 1: actual movement of the celestial bodies and you're able to
Speaker 1: represent them accurately, there are multiple ways to actually achieve that,
Speaker 1: and that's the cool thing. Is that we've seen lots
Speaker 1: of different approaches to this particular problem and all of
Speaker 1: them work. They just work in different ways, which is
Speaker 1: pretty awesome. It just shows the ingenuity of people when
Speaker 1: it comes to I want to represent this thing that's
Speaker 1: in nature, how do I do that? And people come
Speaker 1: up with completely different ideas that all work the uh
Speaker 1: you know, equally well, just in different ways. So we
Speaker 1: actually have we have a couple of planetariums here in
Speaker 1: Atlanta that uh you know, I think fern Bank has one,
Speaker 1: but Emory also has one, and uh, Emery is interesting
Speaker 1: for a couple of different reasons. One is that it
Speaker 1: it's a classroom as well as a planetarium, so it
Speaker 1: can actually double up. And in fact, the planetarium stuff
Speaker 1: can fade off into the background so that it can
Speaker 1: just be a regular schoolroom. And by by by fade off,
Speaker 1: you mean you mean sink into the floor like a
Speaker 1: super villain layer. Apparently in Atlanta we have this thing
Speaker 1: about incredible equipment sinking into the floor. It's it's the
Speaker 1: planetarium at Emory, it's the Mighty mo Organ over at
Speaker 1: the Fox Theater. Why don't why don't we have this
Speaker 1: in the office anywhere? Yeah, you know, I think Ben
Speaker 1: sunk into the floor once, but I'm not sure that
Speaker 1: anyone besides me saw it, so I could just be crazy,
Speaker 1: but I don't know. Sometimes he likes to make me
Speaker 1: think that. The other reason why I wanted to bring
Speaker 1: it up is because the planetarium itself has a projector
Speaker 1: called the Zeiss Skymaster z k P three, which is
Speaker 1: cool because it's it's Yeah, it's from the same company
Speaker 1: that made the very first planetarium projector, so again, they're
Speaker 1: still in business, they're still making that. This one was installed,
Speaker 1: I believe in two thousand two, so it wasn't it
Speaker 1: wasn't that long ago. Now, the one at Emory is
Speaker 1: computer controlled. It's got a keyboard for manual input and
Speaker 1: has thirty nine different projecting lenses of different sizes that
Speaker 1: create the stars, planets, and other celestial bodies on the
Speaker 1: inner surface of the dome, and can project more than
Speaker 1: seven thousand individual stars, plus star clusters, nebula galaxies, the
Speaker 1: Milky Way, the planets, Sun, the Moon, and it can
Speaker 1: superimpose lines between stars to illustrate constellations. So if you
Speaker 1: hear about these constellations and you think I just looks
Speaker 1: like a cluster of stars. I don't. I don't get it.
Speaker 1: Then they can actually show the connections that uh the
Speaker 1: inspired the imaginations of people thousands of years ago to
Speaker 1: call the stars wacky things like Oryan. Yeah, I always
Speaker 1: had trouble with those. The only one I could ever
Speaker 1: pick out was O. Ryan, because I could pick out
Speaker 1: A Ryan's belt. But otherwise I was, I was hopeless.
Speaker 1: I was. I was a whiz at it. When I
Speaker 1: was a kid. I had a really big astronomy phase. Yeah,
Speaker 1: I wish I had taken a course in astronomy. I
Speaker 1: never did. Uh. The one that Emory also usually shows
Speaker 1: the sky over Atlanta. Again, no big surprise, but because
Speaker 1: it is a computer system, it's one of those that
Speaker 1: can show you the sky over any given point on
Speaker 1: the art at any given time, so you can set
Speaker 1: it for whenever. Now. Um. The other cool thing about
Speaker 1: is that it's connected to a telescope that's on the
Speaker 1: building's rooftop, and they have a direct video feed from
Speaker 1: the telescope to the planetarium, so for astronomical events you
Speaker 1: can go and you know, yeah, just watch it, and
Speaker 1: just watch it from on the ceiling of this planetarium,
Speaker 1: which is you know, you could see a live event.
Speaker 1: They they've hosted several live events there, not all of
Speaker 1: them were some that you could watch through the telescope. Like, uh,
Speaker 1: I'm pretty sure that the Mars Rover landing you probably
Speaker 1: couldn't see through the telescope. I cannot imagine that would
Speaker 1: be possible now. But but they do show some interesting
Speaker 1: feeds from various sources. So the days, I mean, as
Speaker 1: impressive as that planetarium is and as proud as I
Speaker 1: am as a as a native at Lantin, that's here. Uh,
Speaker 1: there are others that are even more sophisticated. We're talking
Speaker 1: four K or eight K projectors. So you know, think
Speaker 1: of the general rule of thumb, and granted it's a
Speaker 1: rough rule of thumb, is four K means four times
Speaker 1: the the resolution of say a ten eight high definition television.
Speaker 1: That that's when you get into ultra high definition. Yeah,
Speaker 1: this is this is way more high def than your
Speaker 1: local cinema. Yeah, eight K even more so. Uh yeah,
Speaker 1: even if you have a four K cinema near you,
Speaker 1: eight K twice as good really as when you get
Speaker 1: down to it. Again, that's very rough. I mean, anyone
Speaker 1: who's a true video file is cringing when I say this,
Speaker 1: but yeah, you can go and see planetariums use eight
Speaker 1: K projectors. Some of them have full three D effects
Speaker 1: at six D frames per second, so you can actually
Speaker 1: feel like you're floating through space. They can take you
Speaker 1: on on journeys all the way around the Solar System
Speaker 1: and the galaxy. You've got data feeds from all over,
Speaker 1: like including space probes. It's pretty incredible. So oh yeah, yeah,
Speaker 1: some of these things can show over nine thousand stars
Speaker 1: that ago, go backward and forward ten thousand years into
Speaker 1: the past and future. Um and and right take you
Speaker 1: so far beyond Earth to to show any kind of
Speaker 1: any kind of data that we have anywhere in the universe.
Speaker 1: Um and you can you can composite the astronomer's data
Speaker 1: and and artists composits. Yeah, it's fantastic. I love the
Speaker 1: idea of also being able to see things like here's
Speaker 1: what the night sky would look like if you were
Speaker 1: on Mars, right. I mean, that's incredible stuff that we
Speaker 1: clearly most of us are not going to ever have
Speaker 1: the chance of looking at the stars from the surface
Speaker 1: of another planet, or to go into the center or
Speaker 1: a galaxy and check out the black hole there. Yeah,
Speaker 1: I had plans and they got canceled. The other couple
Speaker 1: that was gonna go with us something came up, and
Speaker 1: when that happened, Yeah, so rude. That's the nice thing
Speaker 1: about the planetariums is they give us this opportunity to
Speaker 1: journey to places we physically could not get to and
Speaker 1: really understand more about our galaxy and the way everything
Speaker 1: seems to work in relation to each other based upon
Speaker 1: our knowledge now. And the other nice thing about planetariums
Speaker 1: is that these facilities update as our understanding grows. So
Speaker 1: there are times when we might learn something that ends
Speaker 1: up affecting the way a planetarium is displaying the night sky,
Speaker 1: and it's pretty easy with digital projection to fix it relatively. Yeah,
Speaker 1: and so you might even be able to watch something
Speaker 1: like here's what a supernova looks like. And you know,
Speaker 1: there there have been events in the past where they've
Speaker 1: been amazing astronomical events, but many of them happened before
Speaker 1: most of us were alive, So it'd be really cool
Speaker 1: to be able to see those kind of representations things
Speaker 1: like uh Hallie's comment as another good example, or maybe
Speaker 1: if you wanted to see what it would look like
Speaker 1: with some of the other famous comments that have gone by,
Speaker 1: but you never chance when they actually happened. Maybe it
Speaker 1: was cloudy that day, or maybe you weren't born yet,
Speaker 1: it would give you the opportunity. So super cool stuff.
Speaker 1: Um really interesting again to look into it, and the
Speaker 1: fact that so many different people have created similar but
Speaker 1: different approaches for this same purpose is really cool. I mean,
Speaker 1: it's it's it's rare when we talk about a technology
Speaker 1: where there are all these multiple pathways that get to
Speaker 1: the same destination. Usually we talk about convergence, where you know,
Speaker 1: competing technologies start to fall away until you have a
Speaker 1: clear front runner or maybe two possible ones. But with
Speaker 1: this there are lots of different ways. Oh yeah, and
Speaker 1: all of these interactions with multiple disciplines of of bringing
Speaker 1: together the knowledge that we have been gathering over the
Speaker 1: centuries about the universe around us, along with the optics
Speaker 1: fields that have let us use these technologies to to
Speaker 1: project stuff onto a ceiling. Yeah, I mean it's I mean,
Speaker 1: it sounds it sounds so ludicrously simple when you say
Speaker 1: it that way, right, But yeah, all you have to
Speaker 1: do go to go to a planetarium. Guys, go to
Speaker 1: a planetarium, and especially if the the projector is something
Speaker 1: that's that's in view, take a really good look at
Speaker 1: that thing, because send us pictures of it if they
Speaker 1: let you. They're pretty phenomenal. Yeah. Yeah. And if you
Speaker 1: work at a facility that has a planetarium and you think, hey,
Speaker 1: the tech stuff, guys, they should really go and see
Speaker 1: this place, let us know because we totally would go. Yeah.
Speaker 1: I mean, I like Pink Floyd as much as the
Speaker 1: next guy. So they're one of the planetariums in Atlanta,
Speaker 1: would do Pink Floyd show. I think there would be
Speaker 1: a little lasers that would go on inside and stuff. Um,
Speaker 1: not really my scene, actually, I just I'd like to
Speaker 1: reference it. But no, we really do find this kind
Speaker 1: of stuff fascinating. So guys, if there's a technology that
Speaker 1: you find fascinating but you've always wanted to know more about,
Speaker 1: you want to know the history, you want to know
Speaker 1: how it works, you want to know the the social implications,
Speaker 1: how is it culturally significant? Anything like that. Let us
Speaker 1: not send this email our addresses tech stuffs at Discovery
Speaker 1: dot com, or drop us a line on Facebook, Twitter
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