The Orbit Interview – Theodore Hall
Theodore W. Hall is well known to the Space Architecture community as a long-time leader of the SATC and specialist in modeling of artificial gravity environments. He is one of the developers of the University of Michigan virtual reality environment MIDEN (Michigan Immersive Digital Experience Nexus) where he integrates digital models and custom codes and the interactivity of the environment. His roots are connected with development of early tools for Computer Aided Design (CAD) and Building Information Modeling (BIM) systems development as well as visualization.
He was the AIAA DETC Aerospace Architecture Subcommittee Chair from 2006 till 2008, SATC Vice-chair from 2008 till 2010 and SATC Chair from 2010 till 2014. He also co-chaired the 1st Space Architecture Symposium in 2002 (with Marc Cohen and Scott Howe), and chaired the space architecture sessions at the International Conference on Environmental Systems (ICES) in 2007-2010 and 2013-2014. He managed to transform and lead the SATC into a fully sustainable body providing a unique networking and collaborative platform for the next generations of space architects.
The interview was conducted by SATC current chair Ondrej Doule.
Orbit: When have you started to be interested in architecture or space architecture?
Hall: My favorite toys as far back as I can remember were building kits like Lego and Erector Set. As a teenager, after outgrowing Lego, I built a scale model of our family house from balsa wood, paper, wire, and whatever else I could find that fit the scale, including details like the furnace in the basement and all of the connecting ductwork.
But I also remember way back, that on a basement wall next to a world map was a map of the solar system. We also had a school lunch box with astronautics artwork on the lid, and my older brother had a stack of Topps “Target Moon” bubble gum trading cards. Growing up in the US during the Space Race, we saw many of the early manned launches on live television. My elementary school would interrupt class and wheel a television into the classroom.
So, building and space were two ideas I grew up with.
Orbit: Who or what influenced you the most in pursuing the artificial-gravity space-architecture topic during your studies or work?
Hall: It was a progression of interests. I took my first computer-programming course (n FORTRAN) as a junior in high school in 1973-74, but I’d already made up my mind to study architecture. So, after high school I entered the pre-architecture program at Grand Rapids Junior College in 1975, and transferred into the College of Architecture and Urban Planning at the University of Michigan in Ann Arbor in 1977. I finished the B.S. in Architecture in 1979 and the M.Arch. in 1981. In those days, a semester of computer programming (again in FORTRAN) was a required course in the undergraduate architecture program. That one semester course went deeper than the entire year in high school. In the M.Arch. program, I took a further elective course in computer graphics programming. I and two classmates also wrote a computer graphic program as our final project for a class in advanced lighting design, and I continued working on that for two semesters of independent study.
In the spring of 1980, the professor in the computer graphics class announced that the Architecture and Planning Research Lab had a job opening for a student programmer. I’d planned to return to my draftsman job in a small architectural office in Grand Rapids where I’d worked the previous two summers. But Michigan was in a building slump and when I got back to the office I found that he had no work. So, I called the professor to confirm that the programming job was still available and moved back to Ann Arbor. I worked full-time during the summer and continued part-time during my final year in the M.Arch. program. I graduated from architecture school “with distinction” as a professional computer programmer. The Lab hired me as a Systems Research Programmer.
My job funding was dependent on “soft money” from external sponsors. When the funding ended in 1986, so did my job. I pondered whether to go back to pencil and paper and try to restart my architectural career after 5 years away from the drafting board, or whether to stick with research. In 1986, AutoCAD was just starting to make its way into architectural practice, and the systems I had been working on were conceptually way beyond what AutoCAD was doing.
In the Lab I’d gotten to know some doctoral students and what they were doing for their dissertations, and considered that was something I could do. But not just for another degree; it would have to be for a research topic that I loved. I enjoyed my Lab work, but it was mostly about implementing other people’s dissertations. I took a long walk one day and decided to apply to the Doctoral Program in Architecture. But for my Statement of Purpose, instead of writing about computer-aided design or building information modeling, I wrote about artificial gravity in space colonies. I had read books by Thomas Heppenheimer and Gerard O’Neill and was fascinated but somehow unconvinced by the imagery of the Stanford Torus and similar concepts. I decided not to pull any punches. I opened my statement with:
“I was born the same year as Sputnik, and like many members of my generation, I want to be a spaceman when I grow up.”
I was 29 years old at the time. I resolved that if they accepted my application, I would be a doctoral student and research artificial gravity in space colony design. If not, then I’d try to restart my terrestrial architectural career, or maybe a career in commercial CAD system development.
The admissions committee accepted my application, though I heard through the grapevine that one of them said it was the most bizarre statement he’d ever read.
Orbit: Space architecture is a very divergent field. It is tightly bound with physics but also with ethics and real human needs that are not always considered priorities. It may be difficult to find balance between objective and subjective design criteria. How do you perceive it?
Hall: When I’m surrounded by engineers I sometimes feel the need to defend architecture. I point out that architectural education includes required coursework in structures, thermal systems, lighting systems, acoustics, and other aspects of building technology, as well as “design.” And while one may become a registered professional engineer with only a four-year bachelor’s degree, professional architectural registration requires at least a five-year bachelor’s, or more typically a six-year master’s degree.
But when I am surrounded by architects, especially design academics, I am frequently struck by the apparent disregard for anything other than artistic form. It irks me to see architectural “design” divorced from technical realities of function, environment, material, and load. I have spoken to aerospace faculty who have told me they have tried to collaborate in space habitat design with their architecture colleagues, but the architects have seemed disinterested in solving the actual problem. Architectural designers who are ignorant or defiant of the laws of physics discredit the whole profession. And as Vitruvius wrote two millennia ago: “If our designs for private houses are to be correct, we must at the outset take note of the countries and climates in which they are built.”
Orbit: Artificial gravity – Why do you think there is no centrifuge on orbit yet. A centrifuge could certainly provide a solution to major health problems.
Hall: Most early space-station concepts, from Tsiolkovky in the 1880s until Skylab in the 1970s, featured artificial gravity as the principal determinant of form. There was a lot of uncertainty as to whether people could survive in microgravity, or for how long. Space stations were conceived as observational outposts for earth science, astronomy, or national defense, or as refueling stations for interplanetary missions. Microgravity was seen as an inconvenient curiosity and potential danger, but not a goal.
As manned space missions got longer without killing anybody, mission planners gained confidence that crews could survive microgravity for indefinite periods. Ultimately, the Salyut and Skylab missions included microgravity itself as a research interest, and artificial gravity was seen as an unnecessary complication. We now have ample experience with astronaut rehabilitation to Earth gravity after six months of microgravity in low-Earth orbit.
It’s a little ironic that the same missions that have shown that humans can survive microgravity for several months have also shown how dangerous it is over the long run.
A Centrifuge Accommodation Module was built and was supposed to fly to the ISS in 2006, but it was cancelled in 2005 due to scheduling and cost problems. It would have supported artificial gravity research on small animals, but not on humans.
Orbit: Why has architecture been introduced in the space sector? Can’t its purpose be served by system engineering or mission architecture? Why should the space sector care about having a more traditional architectural approach?
Hall: Engineers tend to distill the human organism into a system of systems that behave predictably according to physical laws. Humans have mass and occupy volume; they turn carbohydrate and oxygen into carbon dioxide and water; they turn water into urine and non-digestible stuff into feces; they turn calories into heat and work; and that’s about it. The non-rational aspects of humans that can’t be expressed in mathematical functions have no place in hardcore engineering design. Non-rationality is seen as irrational; the crew just shouldn’t behave that way.
The battle to include an actual window in Skylab, and the “crew strike” during the Skylab 4 mission, I think were eye-openers for space mission planners.
Orbit: What is your realistic vision for space architecture in 20-50 years?
Hall: The first application of artificial gravity might be in crewed missions to Mars. Planners are divided. Some see that the one-way transit time is comparable to current typical Earth-orbital missions and conclude that artificial gravity is an unnecessary complication. Others consider that astronauts to Mars will have to arrive there in good physical condition, ready for strenuous work in a rough environment, with no manicured terrain, welcoming ground crew, or time for rehabilitation. And after weeks or months in partial gravity, they’ll need to make another multi-month transit and return to Earth in some kind of rehabilitatable condition.
But the biggest health hazard in Mars transit – more than microgravity – might be radiation. Unfortunately, the best way we know to protect the crew from radiation is with mass, and the mass of radiation protection further complicates artificial gravity. If the whole vehicle is spun up, then that mass has to be accelerated with some kind of energy input. And once it’s spun up, it acquires weight that has to be supported by additional structural mass, which also has to be spun up, and so on.
Rather than spin the entire transit vehicle, there’ve been several proposals for short-arm centrifuges to fit inside the vehicle for periodic doses of artificial gravity. Those have their own complications in terms of crew scheduling, mass balance, and momentum isolation. It would be tricky to rotate a human-sized centrifuge with a 2-meter or so radius without imparting some equal and opposite angular momentum to the rest of the vehicle, but a few concepts have been published.
Ultimately, if we’re ever going to become a spacefaring civilization, I think artificial gravity is inevitable. If not for Mars, then for the main belt asteroids, or the moons of Jupiter, or permanent colonies of the kind that Gerard O’Neill popularized. It’s still not clear how those colonies would support themselves economically. The only economic rationale that the 1970s studies could foresee was construction and maintenance of space solar power satellites.
But who could foresee the economy of North America when the first Europeans arrived? The original economic incentives were commodities like gold, fur, and timber. Now our chief exports are things that the original European colonists could never have imagined.
I can hardly begin to predict what the next 50 years will bring.