Ohio State University Radio Observatory
The Ohio State University Radio Observatory was a Kraus-type radio telescope located on the grounds of the Perkins Observatory at Ohio Wesleyan University from 1963 to 1998. Known as "Big Ear", the observatory was part of The Ohio State University's Search for Extraterrestrial Intelligence (SETI) project. 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.
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, the Big Ear received the noted 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. The design of the observatory is named after American physicist John D. Kraus (1910–2004), and is also used as the basis for the Nançay Radio Telescope.
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 1972, the United States Congress voted to stop funding the Ohio Sky Survey with support from the National Science Foundation. Many people lost their jobs.
On August 15, 1977, the Big Ear recorded its greatest success when an interesting radio signal known as the Wow! signal was received, named for the notation made by American astronomer Jerry R. Ehman. No other such signal was recorded.
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 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.
- Kraus, John D. (1995) . Big Ear Two: Listening for Other-Worlds (2 ed.). Cygnus-Quasar Books. ISBN 1-882484-12-6.
- The Big Ear Memorial Site
- Big Ear Inventor John Kraus Dies
- Video presentation and tour of "Big Ear": , ,