Begun in 1973, the Ohio State University SETI program is a continuously running electromagnetic Search for Extra-Terrestrial Intelligence.
On August 15, 1977 while working on a SETI project at the Big Ear radio telescope of the Ohio State University, Dr. Jerry R. Ehman detected a signal which seemed to fit all the characteristics anticipated for communications of potential intelligent extra-terrestrial origin. It lasted for 72 seconds but has not been detected again. Amazed at how closely the signal matched the expected signature of an interstellar signal, Ehman circled the signal on the computer printout and wrote the comment "Wow!" on its side. Though over a hundred follow-on studies of the same region of the sky were performed, from several different radio observatories, the signal never repeated.
The code 6EQUJ5 describes the intensity variation of the signal. The "Wow!" sequence itself is not a message. The numbers and letters in the much-reproduced computer printout are merely a time-series representation of the signal amplitude, as received at the Big Ear radiotelescope. Specifically, the symbols represent the number of standard deviations by which the received signal exceeded average background noise.
Location of the signal: This region of the sky lies in the constellation Sagittarius, roughly 2.5 degrees south of the fifth-magnitude star Chi-1 Sagittarii (seen here as the blue star to the upper left).
The location of the signal in celestial coordinates was, at (epoch J2000.0)
Declination -26d57m ą 20m
Right Ascention -19h17m24s