Episode 21: Under the Dome
Hightower Back when I was a kid my parents would take me to the Fort Worth Museum of Science and History. This was back in the eighties - well before museums had all the hands-on exhibits and interactive play areas they do today.
Even so, it was an amazing place.
Hightower The museum had giant dinosaur bones and tanks full of slithering reptiles. It had dioramas of cavemen and exhibits about the human body. I’m sure visiting the museum of science and history as often as I did is part of the reason why I’m still interested in both science and history. It may also have been one of the reasons why I became an architect.
It’s not that the building that housed the museum was anything all that noteworthy. But it contained inside of it a room that was truly magical.
I’m talking, of course, about the planetarium.
That’s what we’re going to talk about on this, the twenty-first episode of The Works; a podcast about the world we build around us.
I’m Brantley Hightower.
To get to the Charlie Mary Noble Planetarium you had to take this great spiraling ramp up to the top of the lobby. The planetarium was circular in plan with a great dome overhead. It sounded different in that space. It felt different, too. And of course, once the lights went down things really started to get interesting. More than anything I remember how crisp the stars were against the inky blackness. I remember sitting under the dome and seeing the constellations and the planets above me. I remember time being sped up those planets and stars whirling overhead.
When I had kids of my own I wanted to share this experience with them. And so when we were in Fort Worth a few months ago we made a special trip to see a show in the Noble Planetarium.
But the experience we had there was somewhat different from what I had remembered.
For one, it was a completely different planetarium. The one I went to as a child was demolished in 2009 when the museum underwent a massive renovation. The new planetarium was about the same size as the old one but it had an updated projection system that allowed more than just stars and planets to appear on the dome.
Specifically it allowed Elmo to appear.
Big Bird Hey, do you recognize that voice? Who is it?
Elmo Oh, hi everybody! Hi Big Bird! Oh, Elmo so happy to see all of you. Hi!
Hightower The particular presentation we saw was a half-hour show called “One World, One Sky”. The girls enjoyed the imaginary trip from Sesame Street to the moon but I have to admit I was less convinced. It wasn’t the Muppets that bothered me, but the quality of what was being projected onto the dome. The stars didn’t seem to be as bright and the sky didn’t seem to be as dark.
I know I sometimes remember things from childhood as being more impressive than they were and I wondered if that was the case here. Could planetarium technology have gotten worse over the past thirty years?
It was then I realized that I knew very little about planetariums or the history of their development.
Here’s what I found out.
Since mankind first looked skyward he has sought to understand and explain the movements of the heavens above him. Despite the sophistication of early civilizations such as the ancient Greeks and the Anasazi of North America, it wouldn’t be until well into the twentieth century that a truly functional planetarium came to be built.
Until then the best that could be done was to build a big hollow ball, poke some holes in it and climb inside. That’s what they did in Chicago in 1913.
Doug There was a sphere – called the Atwood Sphere – that was a spherical piece of lead.
Hightower That’s Doctor Doug Roberts. Back in the early 2000s he was an astronomer working at the Adler Planetarium in Chicago. Although they have a modern planetarium facility they kept the century-old Atwood Sphere on display to show how far things had come.
The technology used by the sphere was remarkably simple:
Doug And they drilled holes at the appropriate places for stars such that when the sphere was put outside and you were the outside of building, you were on the inside of the sphere, you would see the sunlight coming through the holes where the stars were.
Hightower Of course the limitations of this approach are easy to imagine. You can only fit a small number of people inside the metal sphere and it could get pretty hot. While the sphere could be rotated to simulate the apparent movement of the stars, there was no real way to animate the independent movement of the planets.
It turns out the Atwood Sphere was the last of its kind. The following year a German optics company figured out a way to shine light through a series of clustered lenses to project stars onto a hemispheric dome. These lenses could be rotated as a unit to simulate the rotation of the earth.
Doug You could put effects of planets moving at different rates to the stars, and so you can kind of make that happen.
Hightower It was an incredibly accurate simulation of what it would be like to be sitting outside and looking up at the night sky. In a way it could be thought of as an early steam-punk virtual reality.
Because the instrument was mechanized and calibrated, time and space could be manipulated. You could see what the night sky would look like on that evening. You could see what it would have looked like in Jerusalem two thousand years ago or what it might look like in Toledo two thousand years in the future. It was truly a theater of space and time.
Early audiences marveled at the realism of the projected stars and planets. It was a form of public entertainment but it was based on a scientifically accurate replica of the night sky. It’s worth noting that when the first public exhibitions of the system began in the 1920s and 30s, light pollution was already becoming an issue in larger cities. Streetlights and other means of artificial illumination were making the night sky less and less visible. The modern planetarium could restore what had been taken away by the modern electric light.
Early lens-based projection systems were pretty expensive and at first only the largest cities with the wealthiest philanthropists could afford to build them. New York, Chicago, Philadelphia and Los Angeles were first to build planetarium facilities in the United States. After the Second World War a simpler system was developed that used a perforated sphere instead of individual lenses to project stars onto a dome. These “star balls” were less expensive and so more institutions could afford to build a planetarium.
But the cause of the largest boom of planetarium construction came in 1957 when a new object began to make its way across the heavens.
Hightower The United States was supposed to be the economic and technological leader of the post-war world. It caught everyone off guard when the Soviet Union launched Sputnik One and beat us into space. Of course the big fear was if they could build a rocket to put a satellite into orbit the Soviets could also build a rocket to put a nuclear warhead anywhere they wanted.
Because the Soviets were doing better than us in space it was assumed they were also doing a better job of teaching their children science and math. This caused a major reassessment of public education in the United States. The federal government became involved and sought to strengthen science education through the National Defense Education Act of 1958. Seventy million dollars were allocated to public schools for “eligible science equipment for teacher demonstration”. A planetarium was considered equipment for teacher demonstration and as a result planetaria began to be built in high schools and colleges across the country.
One of the schools that took advantage of this program was Richard King High School in Corpus Christi, Texas.
Peck My name is Laura Peck, and I'm the Director of the Robert Wollman Planetarium in Corpus Christi ISD.
Hightower Laura isn’t originally from Corpus Christi. She’s from Los Angeles where her first planetarium experience was at the Griffith Observatory – the same one featured in the James Dean film, Rebel Without a Cause.
James Dean (as Jim) You’re tearing me apart!
Hightower The Griffith Observatory belonged to that first generation of planetaria located in major cities and funded by wealthy patrons. The planetarium Laura operates was part of the third generation: the one inspired by – and funded as a result of – the launch of Sputnik One.
Peck In the 1960s when King High School was being built the Federal Government was trying to promote math and space science careers for high school students, so they offered a grant called The National Defense of Education Act. The Corpus Christi ISD School Board at the time applied for this grant and it helped high schools that were currently under construction to build either a planetarium or an observatory.
Hightower In Corpus Christi they used the funds to build what is now called the Robert Wollman Planetarium.
Peck It seats 100 people. The chairs are original. They've been re-upholstered, but they are original to the Planetarium. I've been told the diameter of the dome is 33 feet.
Hightower The height is about 33 feet as well. Sitting in the middle of it all is the original GOTO Mercury Star Ball Projector.
And it is a beautiful piece of machinery. Mounted on two sets of spindly legs, the projector consists of two sky balls that throw the stars of the northern and southern hemisphere onto the dome above. Beyond these are a series of rotating disks for each of the planets and the moon.
When it comes to life the projector’s various motors and gears make a fulfilling mechanical sound. But most people don’t pay attention to the projector – they are far too busy taking in the night sky that appears above them.
Peck It's a great facility that we have. Our star projector, the star field, looks very realistic. The students even tell me the ones on the videos and the computer, you can tell it's a computer. But this one actually makes it look very similar to the night sky.
Hightower Even today an analog star ball projector like the one at King High School looks like a ray gun from a science fiction movie. I can only imagine how futuristic it looked to a high school student in the 1960s.
The control panel, however, is another story.
The plywood console consists of a series of metal dials and knobs. Laura removed the back panel to reveal the vintage rheostats, capacitors and transformers that still control the projector today. This technology looks like it’s a half a century old – which of course it is.
Now maintaining a system like this can be a challenge. There aren’t that many planetarium repairmen around anymore and locating parts for a fifty-year-old machine is challenging at best. That’s why most planetaria that were built in the 50s and 60s replaced their aging analog projectors with digital projectors in the early 2000s.
That’s exactly what happened at the planetarium in San Antonio.
Like the one in Corpus Christi, the original San Antonio College planetarium was paid for with a grant from the National Defense of Education Act. It opened in 1961 and made use of a analog Minolta Star Ball projector. In 2014 the planetarium was rebuilt and expanded to become the Scobee Education Center, a venue dedicated to educating students about space and space exploration.
Today the planetarium is run by Michelle Risse.
Michelle I am Michelle Risse, I am the planetarium coordinator here at the Scobee Education Center.
Hightower Michelle is also an astrophysicist, a subject she first became interested in when she went to a planetarium show as a kid.
Michelle Ever since I was a little girl, when I first saw my first planetarium show at the age of 10, I was just enamored… And after that, I went to my first star party and I got to see Saturn for the first time through a telescope and it was just like, "Wow, it really does have rings. And so I just kept wanting to know more and more and more and it just became an addiction and so that's where I am today.
Hightower And where she is today – or at least where we were sitting when we spoke to one another – was inside the dome of the Scobee Planetarium. Like the one in Corpus it seats about 100 people. But something here is missing.
There is no futuristic ray gun rising into the center of the space. There is no star ball. Instead a series of small, barely noticeable projectors sit along the base of the dome.
These digital projectors are the next step in the development of planetaria. Although they represent cutting-edge technology, the quality of these digital systems isn’t as good as the older analog systems. The contrast is less and the resolution isn’t as crisp. But the system is much more flexible. Digital technology allows anything to be projected onto the dome – including content produced by other institutions.
That’s how I ended up in a planetarium with Elmo.
Michelle And we have two projector systems that produce a 4K resolution image up onto the dome using the latest technology of Digistar 5.
Hightower What is Digistar 5 you ask?
Michelle Digistar 5 is a planetarium program that allows people to be able to not only present full dome images from the best companies across the globe, but also to be able to produce their own material. And that's our next step is to be able to produce something from Scobee Education Center and be able to have it produced live across the globe.
Hightower Over the course of the twentieth century as our knowledge of the universe has grown planetaria have been able to tell less and less of what we actually know. An analog star ball Planetarium does a great job of showing what we can see from Earth, but we now know what the cosmos looks like from interplanetary space probes and physics-based computer models. One big advantage of digital projection systems is that they allow presentations to include this newer imagery.
Michelle The whole point of a planetarium, whether it's a simple little projector or a star ball or the latest and greatest in projector systems is to basically be able to show how amazing our cosmos is. How amazing our world is.
Hightower Planetaria came to occupy a curious place within the scientific community. Although they are precise instruments for disseminating scientific knowledge, they’re of little value for scientific research. Or at least that has been the case in the past.
Remember Doctor Roberts from the beginning of the episode? He was at the Adler Planetarium in Chicago but now he’s the Chief Technology Officer at the Fort Worth Museum of Science and History.
As a research astronomer Doctor Roberts is tasked with analyzing large data sets from sophisticated instruments such as radio telescopes. His job is to take that raw information and try to understand what it means and how it’s all related. He found a tool already existed to help visualize all that data. He found he could use a planetarium.
Doug My motivation, because I came from the research astronomy side, was to use a planetarium as a visualization environment to look at datasets. You have to have the ability to do real-time content. In other words you have to have the ability to look at a 3D object or navigate through a 3d system in real time. I look at this data, I want to look at it from different angles, I want to swap in things, I want to expose or hide different layers - all those things require interactive systems.
Hightower A traditional analog planetarium was interactive in that the projectionist could illustrate a point by changing the view of the night sky. With a digital projection system anything could be illustrated. It’s really just a large, fully immersive display system. It allows a preschooler to watch Elmo dance around the screen and it allows a researcher to visualize data from multiple points of view.
Doug A full hemispheric dome give you immersion. So it’s easier to put yourself into a data set. It’s easier to be not be so focused on an object. A lot of times when you’re looking through a frame of a computer monitor you’re thinking of objects andin a dome you’re thinking about environment, about how things fit together as systems.
Hightower Looking at a three-dimensional map of a data set may not be as entertaining as watching Elmo on the moon, but it’s no less important.
There’s a beauty to learning about the universe while sitting under a star-filled dome. There’s a beautiful symmetry in that the same dome that inspires a kid to want to become a scientist might someday be the same dome they use to discover something new about the cosmos.
The space under the dome is truly a magical place.
Thanks today to Laura Peck of the Robert Wollman Planetarium, Michelle Risse (Riss-E) of the Scobee Education Center and Doctor Doug Roberts of the Fort Worth Museum of Science and History. Thanks also to Jordan Marché whose book, Theaters of Time and Space, provided much of the background information for this episode. Thanks also to my dad who helped me identify the components of the mid-century control panel at the Wollman Planetarium.
The music today was by -
Elmo Excuse me, Mr. Brantley. Elmo needs a thank you, too.
Hightower Oh. Of course. And a very special thanks to Elmo.
Elmo Ha, ha, ha! You’re welcome, Mr. Brantley.
Hightower The music today was by Chris Zabriskie. The Works is a production of HiWorks and you can find more information about it and everything we’ve talked about today at Hi dot Works.
You may have noticed I’ve adopted a “whenever-I-feel-like” approach to episode release dates. Although this means I’m no longer producing a new episode every month, I’d like to think the quality of individual episodes will be greater. If nothing else this flexibility gives me more time to work on other projects and more time to spend with my kids.
Maybe I’ll take them to the planetarium.
Elmo See you there!
Hightower Until next time, I’m Brantley Hightower.