Astronomical Observatory of
The Buhl Planetarium and Institute of Popular Science

The People's Observatory

Buhl Planetarium's long-time Director, Arthur L. Draper, looks through the Institute of
Popular Science's new ten-inch, Siderostat-type refractor telescope in November of 1941.

The Buhl Planetarium and Institute of Popular Science opened to the public on October 24, 1939. However, it would be a little more than two years before Buhl's Astronomical Observatory would be finished and open for public use.

"The People's Observatory" was dedicated, on the third floor of The Buhl Planetarium and Institute of Popular Science, on November 19, 1941. At a cost of $30,000(1941 dollars), a ten-inch, Siderostat-type, refractor telescope was manufactured as the Observatory's primary instrument, by the Gaertner Scientific Company of Chicago. Well-known Astronomer, Harlow Shapley, who was then Director of the Harvard College Observatory, presented the keynote address at the dedication ceremony.

Prior to the dedication of the "Siderostat," Buhl did use the building's third floor for astronomical observing. In addition to the Telescope Room of the Observatory, which uses a flat, roll-away roof(a manual chain is used to open and close the roof) to access the sky, two outdoor wings(east and west of the Telescope Room, hence called the "East Wing" and "West Wing") were also accessible to the public, where portable telescopes were often used.

A four-inch portable, refractor telescope was purchased from the Zeiss Optical Works in Jena, Germany, at about the same time Buhl's Zeiss II Planetarium Projector was received from the same company. However, Buhl officials were quite disappointed when they received this telescope. The Zeiss Optical Works had sent Buhl the wrong type of telescope! The telescope they received was a terrestrial refractor, which corrects for the usual upside-down image of simpler telescopes; this is normally sold to people who would use the telescope to view objects on the Earth, not for celestial viewing(where an upside-down image is irrelevant). Buhl had ordered an astronomical telescope which does not correct for the upside-down image; hence, no detail is lost in the correction process. Buhl officials would have liked to return the telescope to the Zeiss Company for a replacement. However, by this time World War II had broken-out in Europe and trading this telescope for a replacement seemed unlikely(Once the war began, the Zeiss Optical Works in Jena, Germany was converted to make bombsights for German military aircraft; the Allies later bombed the factory.). Hence, Buhl learned to live with a terrestrial telescope until the Siderostat was ready in 1941. This historic, four-inch Zeiss refractor telescope is still in use by the Henry Buhl, Jr. Planetarium and Observatory at The Carnegie Science Center.

An interesting historic anecdote: On the same evening of the Observatory dedication, Buhl started a new Planetarium Sky Show and opened a new gallery exhibit. The Sky Show, regarding Celestial Navigation, was titled "Bombers by Starlight"(Buhl provided Celestial Navigation classes to many military servicemen, during World War II). The new exhibit, in Buhl's lower-level Octagon Gallery(which encircles the planetarium projector pit, below the planetarium theater) was titled "Can America Be Bombed?" This exhibit opened two and one-half weeks before the Japanese bombed Pearl Harbor, Hawaii!

After the October 5, 1991 opening of the Henry Buhl, Jr. Planetarium and Observatory in the The Carnegie Science Center, Buhl's Siderostat-type telescope continued to be used for Science Center classes, until February of 1994 when the decision was made to move all classes to the main building. Portable telescopes used in Buhl's Observatory, including the historic four-inch Brashear refractor telescope and the historic four-inch Zeiss, terrestrial, refractor telescope, were moved to the new Science Center building immediately upon its opening. Several of these portable telescopes are used for the Henry Buhl, Jr. Planetarium and Observatory's astronomical observing sessions, on Saturday evenings weather-permitting, which are free-of-charge to the public. In addition to the portable telescopes, the Science Center's fifth floor observation deck includes an observatory dome, which houses a 16-inch Meade reflector telescope.

"The People's Observatory" - Buhl's Astronomical Observatory -

Description and other information - Aide's Book, Copy 8, pages 36 through 39, 58 through 63.

Description, operating instructions, Observatory program - Aide's Book, Copy 25, pages 20 through 31

Photographs of the Ten-inch, Siderostat-type, Refractor Telescope -
Special Note: "Danger" sign, seen in these images, refers to the danger of looking directly at the Sun through the telescope. Looking directly at the Sun with a telescope, binoculars, or any other optical aid will result in permanent loss of vision!!! This is also true during most stages of an eclipse of the Sun or Solar Eclipse. During a daytime tour of The People's Observatory, the staff member would project the image of the Sun from the telescope onto a large projection screen; people would then safely view the image of the Sun on the projection screen. Not only is this a safe way to view the Sun(and, possibly sunspots and/or granulation on the surface of the Sun), this also allows everyone in the tour group to view the Sun at the same time. The Observatory Tourguide, usually during the daytime tour, would also place a piece of wood close to the eyepiece lens of the telescope(where people would normally look into the telescope to see planets and stars in the evening). The piece of wood would immediately start to burn!!! This very graphic demonstration was presented to emphasize the danger of looking into the telescope at the Sun.

Other Telescopes -
* Brashear 4-inch Refractor Telescope(Now displayed at The Carnegie Science Center) -
> Photographs at The Carnegie Science Center
> Donation, to Buhl, of 37th telescope(circa 1900) manufactured by John A. Brashear - In Buhl Annual Report of Programs, 1972-1973, pages 9, 10, and 11.

History of Astronomer,Educator, and Optician John A. Brashear

"The Theater of the Stars" - Buhl's Planetarium Theater

Henry Buhl, Jr. Planetarium and Observatory at The Carnegie Science Center