Remarkable Ohio

Counties

Below is a complete listing of all Ohio Historical Markers. To find a detailed marker listing including text, photographs, and locations, click on a county below. Our listing is updated by the markers program as new markers are installed and older markers are reported damaged or missing.

1-21 Pioneer Radio Telescope / Big Ear Radio Telescope

Side A: One-half mile east is the site of the former BIG EAR radio telescope. Designed by Dr. John D. Kraus, pioneering radio astronomer at Ohio State University, it had a collecting area of 340 by 70 feet (104 by 21 meters). The observatory was completed in 1963. The Ohio Sky Survey recorded here between 1965 and 1972 was the most accurate, reliable, and complete mapping of cosmic radio signals (the “radio sky”) for many years. BIG EAR gained fame for its ability to detect quasi-stellar radio sources, or “quasars,” and for its discovery of some of the most distant objects known. This observatory conducted a 24-year continuous search for evidence of extraterrestrial intelligence, during which the famous “Wow!” signal was received in 1977. BIG EAR was demolished in 1998. [“Wow!” signal graphic]
Side B: BIG EAR consisted of a flat tiltable reflector, a fixed standing parabolic reflector, and pairs of receiving horn antennas. Radio signals were bounced off the flat reflector, focused by the parabolic reflector, and collected by the feed horns. The telescope used the rotation of the Earth to scan a narrow path across the sky once each day. The Ohio State University and the National Science Foundation funded the telescope’s design and construction, and it was built almost entirely with faculty and student part-time labor. From 1973 through 1997, the observatory was operated and maintained by a dedicated group of volunteer scientists with generous assistance from the National Aeronautics and Space Administration (NASA) and private benefactors. Successful operation of the telescope would not have been possible without the dedication of site technician Eugene (Gene) Mikesell (1931-1987).
Sponsors: Ohio Bicentennial Commission, The Longaberger Company, Ohio State University Radio Observatory, North American Astrophysical Observatory, and The Ohio Historical Society
Address: 3199 Columbus Pike, 
Delaware, 
OH, 
43015
Location: US 23 – Perkins Observatory
Latitude: 40.2492600
Longitude: -83.0576080