The Ohio State University Radio Observatory was a Kraus-type (after its inventor John D. Kraus ) radio telescope located on the grounds of the Perkins Observatory at Ohio Wesleyan University in Delaware, Ohio from 1963 to 1998. Known as Big Ear , the observatory was part of Ohio State University 's Search for Extraterrestrial Intelligence (SETI) project. The telescope was designed by John D. Kraus. Construction of the Big Ear began in 1956 and was completed in 1961, and it was finally turned on for the first time in 1963.
7-455: The main reflector of Big Ear—The Flat Reflector—measured approximately 103 meters by 33 meters, giving it the sensitivity equivalent to a circular dish measuring nearly 53 meters in diameter. The observatory completed the Ohio Sky Survey in 1971, and from 1973–1995, Big Ear was used to search for extraterrestrial radio signals, making it the longest running SETI project in history. In 1977,
14-448: A coordinate numbering system consisting of a two-letter prefix followed by three digits. The first letter, O, stood for Ohio, and the second letter, B–Z inclusive (omitting O) indicated the source right ascension in hours (0–23 inclusive). The first digit indicated the declination zone in increments of 10°, while the last two digits give the source number within the specified region of right ascension and declination. Data reduction for
21-667: Is the Ohio SETI Program at Ohio State University in Columbus, OH, which has searched the universe for extraterrestrial radio signals for 22 years, beginning in 1973. Ohio Sky Survey The Ohio Sky Survey was an astronomical survey of extragalactic radio sources . Data were taken between 1965 and 1971 using the Big Ear radio telescope at the Ohio State University Radio Observatory (OSURO), also known as
28-477: The Wow! signal . The observation would prove to be unique, since no similar signals were ever detected afterwards. Later research indicated the phenomenon was possibly caused by a transient brightening of hydrogen. The Big Ear was listed in the 1995 Guinness Book of World Records under the category of "Longest Extraterrestrial Search": The longest-running full-scale SETI (search for extraterrestrial intelligence) project
35-400: The "Big Ear Radio Observatory (BERO)". The survey covered 94% of the sky area between the limiting declinations of 63°N and 36°S with a resolution at 1415 MHz of 40 arc minutes in declination. The survey was carried out primarily at a frequency of 1415 MHz but observations were also made at 2650 MHz and 612 MHz. Roughly 19,620 sources were identified over the course of
42-501: The Big Ear received the Wow! signal . The observatory was disassembled in 1998 when developers purchased the site from the university and used the land to expand a nearby golf course . From 1965–1971, the Big Ear was used to map wideband radio sources for the Ohio Sky Survey , its first sky survey for extraterrestrial radio sources. In 1977, the Big Ear recorded an unusual and possible extraterrestrial radio signal, which became known as
49-434: The survey of which 60% were previously uncatalogued. The survey was unique in that it covered a larger portion of the sky, to a greater depth, and at a higher frequency, than any previous survey. In addition, all previously catalogued sources were tabulated and maps of the areas surveyed were included with the positions of all catalogued sources. Sources discovered in the course of the survey were assigned names according to
#773226