Sharing the Common Wealth showcases objects, artifacts, documents, structures and buildings from the collections of PHMC.
Model A3P star projector

Spitz Model A3P Star Projector at The State Museum of Pennsylvania. The State Museum of Pennsylvania/Photo by Don Giles


The Planetarium at The State Museum of Pennsylvania first opened to the public on July 14, 1965, and will celebrate its 50th anniversary this year on July 15-19. Early patrons and those who followed until 2004 will recall the tall, unconcealed mechanism emerging from the floor in the center of the theater, as much a part of the show as the stars and planets it projected onto the sky dome ceiling from the 1,354 pinpoint holes of its large revolving starball. The model A3P star projector produced by Spitz Inc. of Chadds Ford, Delaware County, became standard equipment in planetariums around the country by 1970, but the model at The State Museum was among the first 20 to be installed in the world.

The world’s first planetarium projector, the Zeiss Mark I, was manufactured in 1923 by the Carl Zeiss Company in Jena, Germany, and was installed in the Deutsches Museum in Munich that same year. The subsequent Zeiss models were expensive and not widely distributed, although in Pennsylvania, Pittsburgh’s Buhl Planetarium acquired a Mark II in 1939 and operated it until 1994. A Zeiss model was also installed at the Fels Planetarium at the Franklin Institute in Philadelphia in 1933.

In 1936 Philadelphia native Armand Neustadter Spitz (1904–71) went to work for the Fels Planetarium. While there he began thinking about developing less-expensive equipment for planetariums, so that more institutions would be able to establish dome teaching in their communities. In 1946 he founded his own company, Spitz Laboratories, to produce affordable projectors. As the United States entered the Space Age and the federal government increased funding for science education in the late 1950s and early 1960s, numerous planetariums featuring Spitz equipment were constructed in high schools, colleges and museums across the country. Consequently, Spitz’s company (now Spitz Inc.) continued to grow, allowing further technological advances, such as the A3P.

Five decades later, The State Museum Planetarium continues to rely on Spitz equipment, namely the SciDome XD, to present state-of-the-art digital immersive theater programs. The original A3P star projector that was installed 50 years ago is now on exhibit in the Planetarium’s vestibule as an artifact of Space Age technological ingenuity in Pennsylvania.


Kyle R. Weaver is the editor of Pennsylvania Heritage.