The Ohio State University Radio Observatory was a
Kraus-type
The Kraus-type radio telescope design was created by Dr. John D. Kraus (1910–2004).
Kraus-type telescopes are transit instruments, where the flat primary mirror reflects radio waves towards the spherical secondary mirror, which focuses it towar ...
(after its inventor
John D. Kraus
John Daniel Kraus (June 28, 1910 – July 18, 2004) was an American physicist known for his contributions to electromagnetics, radio astronomy, and antenna theory. His inventions included the helical antenna, the corner reflector antenna, a ...
)
radio telescope
A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency ...
located on the grounds of the
Perkins Observatory
Perkins Observatory is an astronomical observatory in Delaware, Ohio. It is owned and operated by Ohio Wesleyan University.
In 1931 it had the third largest telescope in the World; the 69 inch aperture Perkins telescope came online at this obser ...
at
Ohio Wesleyan University
Ohio Wesleyan University (OWU) is a private liberal arts college in Delaware, Ohio. It was founded in 1842 by methodist leaders and Central Ohio residents as a nonsectarian institution, and is a member of the Ohio Five – a consortium ...
in
Delaware, Ohio
Delaware is a city in and the county seat of Delaware County, Ohio, United States. Delaware was founded in 1808 and was incorporated in 1816. It is located near the center of Ohio, is about north of Columbus, and is part of the Columbus, Ohio m ...
from 1963 to 1998. Known as Big Ear, the observatory was part of
Ohio State University
The Ohio State University, commonly called Ohio State or OSU, is a public land-grant research university in Columbus, Ohio. A member of the University System of Ohio, it has been ranked by major institutional rankings among the best publ ...
's
Search for Extraterrestrial Intelligence
The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other pl ...
(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.
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
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 the "Big Ear Radio Observ ...
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
Wow! signal
The Wow! signal was a strong narrowband radio signal detected on August 15, 1977, by Ohio State University's Big Ear radio telescope in the United States, then used to support the search for extraterrestrial intelligence. The signal appeared ...
. The observatory was disassembled in 1998 when developers purchased the site from the university and used the land to expand a nearby
golf course
A golf course is the grounds on which the sport of golf is played. It consists of a series of holes, each consisting of a tee box, a fairway, the rough and other hazards, and a green with a cylindrical hole in the ground, known as a "cup". Th ...
.
History
From 1965–1971, the Big Ear was used to map wideband radio sources for the
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 the "Big Ear Radio Observ ...
, its first sky survey for extraterrestrial radio sources.
![Wow signal](https://upload.wikimedia.org/wikipedia/commons/d/d3/Wow_signal.jpg)
In 1977, the Big Ear recorded an unusual and apparently
extraterrestrial radio signal, which became known as the
Wow! signal
The Wow! signal was a strong narrowband radio signal detected on August 15, 1977, by Ohio State University's Big Ear radio telescope in the United States, then used to support the search for extraterrestrial intelligence. The signal appeared ...
. The observation would prove to be unique, since no similar signals were ever detected afterwards.
The Big Ear was listed in the 1995
Guinness Book of World Records
''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a reference book published annually, listing world ...
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.
Surveys
*
Andromeda Galaxy
The Andromeda Galaxy (IPA: ), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula, is a barred spiral galaxy with the diameter of about approximately from Earth and the nearest large galaxy to the Milky Way. The gala ...
(1963)
*
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 the "Big Ear Radio Observ ...
(1965–1971)
*
SETI
The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other p ...
(1973–1995)
See also
*
List of astronomical observatories
This is a list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no longer in ...
*
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming f ...
References
Further reading
*
External links
The Big Ear Memorial Site
* Video presentation and tour of "Big Ear"
{{Authority control
1963 establishments in Ohio
Astronomical observatories in Ohio
Buildings and structures demolished in 1998
Ohio State University
Radio telescopes
Search for extraterrestrial intelligence