Date: January 13, 2010

Title: Remembering the Atwood Sphere


Podcaster: Elizabeth Fracek

Links: Adler Planetarium

Description: Elizabeth Fracek, a high school English teacher from Oklahoma, discusses her experiences with Chicago’s Atwood Sphere, both at the Chicago Academy of Sciences when she was in the seventh grade, and at the Adler Planetarium as an adult.

Bio: Elizabeth Fracek teaches 11th Grade English, Speech and Drama, and 7th Grade Reading in northeast Oklahoma. She has been interested in space and astronomy since the first time she visited the Adler Planetarium in Chicago when she was a kid.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by Elizabeth Fracek (FRAY-SEHK), and dedicated to The Adler Planetarium, where I learned to love the night sky, and the current home of the Atwood Sphere. Thank you for restoring my old friend.


Hello, and welcome to the 365 Days of Astronomy in 2010! I’m still Elizabeth Fracek, I’m still a high school English teacher in northeast Oklahoma, and I still don’t have much of a right to say anything about astronomy. I’m going to take another whack at this 365 Days of Astronomy thing anyway, because I’m still intensely interested in space and astronomy. On July 13, 2009, my 29th birthday, I talked a bit about my two favorite astronomy-themed places in Chicago, Illinois, which is where I grew up. There was a section of my talk about the Adler Planetarium that I was really excited about, but I had to cut it out due to time constraints, and I am thrilled and pleased to be able to bring it to you now, because it is something very special to me, and I hope it will mean something to you as well.

During the spring semester of 1993, I was a seventh grader at Newberry Academy in Chicago. My mom signed me up for an enrichment Ecology class at the Chicago Academy of Sciences, which was a shortish walk downtown from the school. I got to leave school early one day a week to go learn about conservation and the environment, which was great fun, but what I remember the most (if any of my classmates are listening, please remember that that was seventeen years ago, and my memory is fallible) are the times that we had free rein to explore the museum.

As a fan of Chicago’s Museum of Science and Industry, the Chicago Academy of Sciences wasn’t much to write home about, but as an eternal pragmatist, I was always able to look at the situation in terms of the fact that the Chicago Academy of Sciences was there, and so was I, and I could get in for free because I was taking the class, so why not enjoy what I had, instead of comparing it to somewhere that, much as I loved it, I couldn’t find on a map if my life depended upon it?

The Chicago Academy of Sciences was full of exciting interactive things, but one particular exhibit sticks out: off in a corner on a floor we didn’t often visit was a big white sphere-looking thing with a hole in one side near the floor. The sphere was huge in my twelve-year-old memories, towering over me as if, if it could only start rolling, it would squash me without thinking twice about it. At the same time, though, the behemoth seemed lonely somehow; the dust on the faded velvet ropes blocking the opening was quite thick, and the whole thing had this air of long disuse about it. I always wondered what it was and what it was for, but I never did find out during the whole time I visited the Chicago Academy of Sciences, probably because I figured, in my seventh-grade mind, that it was bad form to ask a teacher about something she hadn’t specifically asked me to study.

Fast forward to January of 2008, and I’m visiting the Adler Planetarium during a road trip to Chicago. As I mentioned last July, the museum had been completely redone in the fourteen or so years since my previous visit, and I did not recognize much of anything while I was there. Once again the eternal optimist, I put away my childhood memories, determined to enjoy what the museum had become, rather than mourning for what had been.

As I said last July, the new museum looks fantastic! I spent several happy hours wandering around the new exhibits, watching video clips, playing with interactive displays, and basically deciding that this new planetarium was much cooler than the planetarium I grew up with. It’s okay to enjoy what is without betraying the memories of what was, after all.

My very last stop during my museum exploration was deep in the lowest level of the museum. The map promised an “Atwood Sphere”, but I had no idea what that was or why I should care, and the display of historical astronomy equipment that was also down there wasn’t high on my list either. I’m a thoroughly modern girl, and old dusty telescopes aren’t really my thing. Still, I didn’t want to miss anything, so I wandered through the historical displays first, saving the Atwood Sphere for last, if I even got there at all.

Of course, I got thoroughly turned around in the history exhibit, and when it spit me out, I had no idea where I was in relation to the map of the building, so I just wandered for awhile. At one point, I thought I saw something that looked vaguely familiar in the corner of my eye, but, since I am often mistaken about such things, I let it go… until I turned a corner absentmindedly and there in front of me was the giant sphere I was sure I remembered from childhood afternoons spent at the Chicago Academy of Sciences. My jaw dropped in confusion and disbelief, but a close study of the displays around the sphere convinced me that – yes – this was my old friend from so long ago, given new life by another old friend, the Adler Planetarium.

I was amazed over and over again as I pored over the information about the sphere and its move across town from the Chicago Academy of Sciences to the Adler Planetarium. I discovered mundane facts, such as that the Atwood Sphere was built in 1913 by Wallace Atwood, who was at that time the Secretary of the Chicago Academy of Sciences. The sphere is fifteen feet in diameter, but it weighs only 500 pounds, because it is made of galvanized steel only 1/64th of an inch thick. The sphere has 692 holes of varying diameters drilled in it, and from inside, light shining through these holes simulates the night sky over Chicago. Spectators stood on a stationary platform while the sphere rotated around them, so that any time of year could be simulated as well. For city people with indoor preferences such as myself, the Atwood Sphere allowed us to pretend we were outside on a clear night watching the stars without actually having to deal with the “being outside” part of the equation. I know I would have thoroughly enjoyed it if I’d been alive during its heyday, probably just as much as I enjoy science museums and planetariums today.

Unfortunately, the Atwood Sphere’s popularity waned during the 1930s when the Adler Planetarium, with its state-of-the-art Zeiss projector (the very same projector still in use in the Sky Theater today) opened. Various projects to rekindle the Atwood’s popularity failed, and it had been all but forgotten at the Chicago Academy of Sciences until 1995, when it was donated to the Adler Planetarium. The sphere had to be very carefully removed from the Chicago Academy of Sciences’ building in six pieces before being moved to the Adler Planetarium and placed into storage.

In the fall of 1996, thanks to financing provided by the Chicago Board of Trade, the Adler Planetarium began a careful restoration of the Atwood Sphere as a part of their greatly-expanded astronomy museum, all of which lead eventually to my reunion with that old, dear friend from childhood in January of 2008.

I’m not sure how I can describe my feelings at seeing the Atwood Sphere, now sparkling and restored, that day at the Adler Planetarium. It was truly like seeing an old friend at a new job – I was excited, happy, proud, and just a bit smug over having this long-ago connection to the Atwood Sphere. I know I cried some happy tears that day, high up inside the sphere and only pretending to listen to the presentation because I was so overwhelmed by seeing my poor, lonely friend restored to its shining glory by the careful work of the Adler Planetarium. It is a day I will not soon, if ever, forget.

Regrettably, there is not very much information available online about the Atwood Sphere, but I’m hoping to change that. As a science fiction geek, it’s incredibly tempting to always be looking forward, toward new horizons, new discoveries, and new technology, but as the Atwood Sphere has shown me, it’s also important to remember where we’ve been, and to cherish the old friends we’ve found along the way, especially when we meet them again in old and familiar, and yet also new and interesting places.

I hope you’ve enjoyed my memories of the Atwood Sphere, and I will be back with another 365 Days of Astronomy episode on July 13, 2010, my *LOUD SIGH* thirtieth birthday! Until then, I hope you enjoy clear skies, old friends, and exciting new discoveries.

Special Thanks: To Marvin Bolt and Devon Pyle-Vowles of the Adler Planetarium for all your help with my research on the Atwood Sphere and how it was moved from the Chicago Academy of Sciences to its new home at the Adler Planetarium, and especially thank you for taking care of my old friend.

End of podcast:

365 Days of Astronomy
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