? – March 1, 2010
by Steve Russo
11,369. A number that forever will live on in my head. All because of one person. One of our colleagues who just passed away. James H. Sharp.
I only met him once, maybe twice, in person, but through a planetarium he helped build, I felt as if I worked with him. In June of 1971, the planetarium that he designed, the Vanderbilt, opened to the public in Centerport, New York.
I had the privilege to work at the Vanderbilt as an intern back in the early 1980’s, and as an adult education instructor in the early 2000’s. This planetarium, even though it was designed and built in the early 1970’s, is still in many ways superior to those built today. When Jim designed it, he designed it with not only the public in mind, but also the staff.
The building was totally self-sufficient containing wood shops, art studios, photo studios, electro-mechanical shops, classrooms and offices. The workspace behind the dome was so designed so that you could have all the lights on and it would not be noticed in the 60 foot dome. All projectors could be serviced from the walkways without using a ladder. Even the HVAC system was designed to almost immediately change the temperature in the theater by many degrees to simulate different temperatures of outer space. Everything was done in house from start to finish. Even the star machine was “custom made” to his specs by GOTO and supplied by Viewlex.
Jim Sharp wanted a star machine that would produce the sky as accurately and as realistic as possible. That’s where the 11,369 comes in. The number of stars, according to Jim, that a person could see who had perfect vision, no light interference from the Moon or lights, and no clouds. I heard two stories on how this number was arrived at, but honestly don’t know which one, or if either are true. One story was that he spent a year or so before the GOTO was built travelling around the globe actually counting stars. The other story is that he did it all mathematically and came up with the number of stars that could be seen down to 6.75 magnitude.
It doesn’t really matter how he derived this number, but the end result was a starfield that would rival today’s planetarium technology. The planets Mercury through Uranus were projected and Jupiter and Saturn had built in 1:6 zoom capability. Variable stars such as Mira and Algol actually varied their magnitude. And Sirius, although slightly exaggerated, showed the star’s parallax-aberration ellipse. The Pleiades had six stars visible to the naked eye, but if you looked through binoculars, you could see 21 of them. Even the GOTO’s Moon projector was able to show perturbations. Solar and Lunar Eclipses could be projected, and the Sun could travel around the entire ecliptic in only 20 seconds! Twenty-one deep sky objects were projected. Due to some ‘custom-designed’ features that Jim wanted, the machine, actually a model GOTO GL-20, was known as the GOTO JHS Custom; the JHS standing for James H. Sharp.
Now I know what you are all thinking. Heck, we can do all of that stuff with today’s digital/video star machines. But remember folks, this was all done with just the star projector, back in 1971! This 13 foot long, almost four ton projector was way ahead of its time.
Such was the mind of Jim Sharp, to design a planetarium that even by today’s standards, Four decades later, could hold its own in the field of Astronomy education. A long time member of our profession, he will be missed.
Rest in Peace Jim.