Robert H. Gray

Lore & Background

Gray first learned of the Wow! signal a few years after its detection on August 15, 1977, by the Ohio State University Radio Observatory (Big Ear). He contacted the Ohio team, visited Big Ear, and spoke with SETI scientist Jerry R. Ehman, project director Robert S. Dixon, and telescope designer John D. Kraus. In 1980, he began scanning the skies from his Chicago backyard using a 12-foot commercial telecommunications dish, operating his small SETI observatory regularly from 1983 for the next 15 years without finding a trace of the signal.

Gray led searches for the Wow! signal using the Harvard/Smithsonian META radio telescope in 1987 and 1989. In September 1995 and May 1996, he and Kevin B. Marvel used the Very Large Array (VLA) in New Mexico, making Gray the first amateur astronomer to use the VLA and the first individual to use it to search for extraterrestrial signals. In 1998, he and University of Tasmania professor Simon Ellingsen conducted six 14-hour observations at the Mount Pleasant Radio Observatory in Hobart, Tasmania, searching for intermittent or periodic signals where Big Ear had detected the Wow! signal, but none were found.

Reader's Guide

Gray's significance lies in his persistent, methodical pursuit of a single unexplained signal, demonstrating that amateur astronomers can access world-class facilities like the VLA for SETI research. His work, published in *The Astrophysical Journal* and other venues, helped define the search parameters for the Wow! signal, including the possibility that it might be intermittent or periodic rather than constant. His 2011 book *The Elusive Wow* summarized what was known about the signal and his own searches, serving as a comprehensive reference. Gray also contributed to the discussion of the Fermi paradox, arguing in a 2016 *Scientific American* article that the paradox does not accurately represent Enrico Fermi's views, as Fermi questioned the feasibility of interstellar travel but did not definitively state whether extraterrestrials exist. His legacy is that of a dedicated independent researcher who advanced the scientific search for extraterrestrial intelligence through observation, publication, and historical documentation.

Did You Know?

• Gray founded the data analysis company Gray Data in Chicago in 1984.
• He became the first amateur astronomer to use the Very Large Array (VLA) radio telescope.
• Gray argued that the Fermi paradox does not accurately represent Enrico Fermi's own views.