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The "Big Ear" Historical Marker
(Dedicated November 5, 2000)

Photos and Text

On November 5, 2000, a Dedication Ceremony for the Big Ear Historical Marker was held commemorating the BIG EAR, Ohio's pioneering radio telescope and the many people who built and used it.

This webpage shows the photos and text present on each side of the marker.

[Note that a larger version of each photo (except the photo showing "1-21") may be viewed by clicking on each image.]

Front Side (Side 1) of Marker

Front side of marker This photo shows Side 1 (the front side) of the Big Ear historical marker.

The text on this side is as follows:


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 on computer printout
On this front side is a photo of the famous "Wow!" signal received by the Big Ear telescope on August 15, 1977 and first noticed by Dr. Jerry Ehman. Since this signal was received only once, there is no definitive explanation for it. However, the signal does have the characteristics expected for a signal from an extraterrestial civilization.

The code '1-21'
At the bottom right of the marker (on each side) is a designation "1-21". It refers to the fact that this historical marker was the 1st marker in the 21st county in Ohio (there are 88 counties in Ohio and if their names are arranged in alphabetical order, Delaware County, where the marker is located, is the 21st county).

Back Side (Side 2) of Marker

Back side of marker This photo shows Side 2 (the back side) of the Big Ear historical marker.

The text on this side is as follows:


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).

Aerial photo of Big Ear radio telescope
On this back side is an aerial photograph of the Big Ear radio telescope.

Marker at Entrance to Delaware Golf CLub (formerly, Dornoch Golf Club)

Entrance to Dornoch Golf Club This photo shows the entrance to the Delaware Golf Club (formerly, Dornoch Golf Club). The Big Ear historical marker is visible near the right side of the photograph.



Copyright © 2004 - 2007 Ohio State University Radio Observatory and North American AstroPhysical Observatory.
Designed by Jerry Ehman.
Last modified: June 13, 2007.