Jones Observatory History

The Clarence T. Jones Observatory (CTJO) was built in 1936 for the local school system using a grant provided by the Public Works Administration (PWA) thanks to the support of Mr. T. H. McMillan (the Commissioner of Education) and the Barnard Astronomical Society (BAS). Initially called the “Brainard Observatory”, the CTJO was the first large public observatory in the south. The name was deservingly changed in 1947 as the original idea for an observatory in Chattanooga was championed by Clarence T. Jones, who was a local architect that designed the building free of charge and also the acting president of the BAS at the time. 

The Cassegrain telescope was not included with the grant for the observatory due to PWA budgetary constraints and was instead constructed separately in 1937 thanks to the generosity of Clarence T. Jones, his sons Arthur and Bruce, and several local engineers and businesses. The telescope mount was cast and poured by the Eureka Foundry Co., who only charged a nominal fee for materials and graciously donated all their labor to the project. Strickland Pattern Works and the Smith Elevator and Manufacturing Company were also involved. 

Glass blanks for the 20.5-inch primary and 5.5-inch secondary mirrors were purchased from Corning Glass Works located in Corning, NY. A 20-inch diameter blank for testing the secondary mirror was acquired later during a visit to Corning by Clarence and his son Bruce and may be one of the initial test pourings for the historic 200-inch mirror at the Palomar Observatory. Grinding and shaping of the mirror blanks were performed in the basement of the observatory on machines built and donated by the Jones family. At the time, it was the largest amateur-built telescope in the United States and of its kind in the Southeast. 

Near the end of the second World War, the City of Chattanooga determined that the facility is “now a liability, rather than an asset” and donated the observatory to the then University of Chattanooga (UC) in June 1944 (UC became UTC in 1969). The observatory was leased for a total of one dollar and for a duration of 99 years. 

The vision of adding a planetarium to the CTJO had been around since the 1940’s. Several “planetarium committees” were developed over the years within the BAS, including one formed in 1950 by Dr. Karel Hujer, the observatory director, astronomy professor at UC, and BAS member. Dr. Hujer and several other BAS members had even traveled to evaluate several different planetariums for insight. In 1951, Clarence T. Jones announced the intent to build a 12-foot “test” dome in the observatory library as a temporary model to inspire public interest. Mr. Jones event built a “Spitz-type” pinhole copper dodecahedron projector at the local Warner Park Hobby Shop for the eventually completed cardboard dome. 

The dream of a planetarium addition was eventually achieved in 1958 thanks to the success of the “test dome” and an anonymous gift that covered the cost of its construction. Designed by the Jones family and built by the O. B. Davis Construction Company, the final design consisted of a 24-foot diameter plaster dome. The original “test” copper dodecahedron projector built by Clarence was then installed with a new control console using a repurposed telephone switchboard. Mr. Jones’ “test” projector was used for planetarium shows until it was retired in 2019. A modern digital projector made by Digitalis Educational Solutions, Inc. is now being used in the planetarium. 

Almost 90 years later, the CTJO still maintains its intended purpose as a facility focused on astronomy and science education. The observatory is open to the public at UTC’s free Star Party events during each semester. Continued investments in the facility by UTC and through generous donations by the BAS, local businesses, and the public have allowed us to continue as a valuable resource to both UTC students and the Chattanooga community.