The Oak Ridge Observatory and the Search for Extraterrestrial Intelligence
Field Report

IN THE HILLS OF EASTERN Massachusetts stands the Oak Ridge Observatory: a picturesque cluster of old astronomical facilities in a grove of pine trees, among which is the only major facility in the United States fully dedicated to the search for extraterrestrial intelligence.

The facility consists of an old but still serviceable 84-foot steerable radio antenna and a control building, located on the edge of the observatory grounds. The observatory belongs to the Harvard-Smithsonian Center for Astrophysics, which has permitted the use of an under-utilized radio antenna by the Search for Extraterrestrial Intelligence (SETI) program.

1134 The SETI antenna at Oak Ridge. CLUI photo
For over 35 years, SETI has been sporadically using various antennas for its quest, as funding and other astronomical programs permit, including the 1,000 foot dish at Aracibo, Puerto Rico. NASA partially supported the program from the 1970's to 1993, but it is almost entirely privately funded now.

SETI started with the astronomer Frank Drake's first searches in 1960, at the Green Bank observatory in West Virginia, and was further popularized by Carl Sagan. The director of the SETI program operations at Oak Ridge is Paul Horowitz, from Harvard University, one of the more well known theorists on the subject.

The Oak Ridge dish has been a full-time SETI site since the 1980s, joining the Parkes antenna in Australia and the Giant Ear in Ohio (which has since been destroyed). The first system at Oak Ridge, called META (Million-channel extra-Terrestrial Assay), was supported by a $100,000 donation from Steven Spielberg, whose now legendary movie ET was being promoted at the time. His son threw the switch to turn on the system at the opening ceremonies.

The META (Million-channel extra-Terrestrial Assay) computer array (at Left) has been retired and stands in a corner of the control building, replaced by the BETA (Billion-channel extra-Terrestrial Assay) computer array (at Right). CLUI photos

In 1995, the program switched over from the META to the new BETA (Billion-channel extra-Terrestrial Assay), funded by the Planetary Society, of Pasadena, California. The new system, 300 times more powerful than META, uses a 250 million channel spectrum analyzer and 32 Pentium 60 processors hooked together, capable of 40 billion operations per second. Over the course of a year, it scans 75% of the sky visible at that location, searching for radio signals that express a pattern which is unlikely to occur naturally, a pattern that may be, in other words, of intelligent origin.

In a nearby structure housing the 61-inch reflector telescope, a new instrument has been installed to "piggy-back" on the conventional astronomy being performed on the scope. This device, designed by Paul Horowitz, and installed this Fall, passively taps into the CCD device on the receiving end of the scope, effectively creating the first (and probably only) full-time optical SETI instrument.