Wow! signal (non-existent audio recording of interstellar radio signal; 1977)

Original printout of the signal with Ehman's written reaction.

Status: Non-existent

On 15th August 1977, while searching the Sagittarius constellation, Ohio State University's Big Ear radio telescope discovered an anomalous interstellar radio signal. Lasting for 72 seconds, it was nicknamed the "Wow! signal" after Jerry Ehman's written reaction to the data discovered. To date, disputes have emerged regarding whether the signal is a possible transmission from an extra-terrestrial entity. But while a printout of the signal is widely available, the audio was ultimately never recorded, despite several elaborate forgeries claiming otherwise.

Background

Four years prior to the Wow! signal's recording, Big Ear had begun searching for possible extra-terrestrial radio signals in a NASA-backed volunteer effort. Previously, very little of interest had been noted by the telescope. However, this changed on 15th August 1977, when it began searching the Chi Sagittarii stars within the Sagittarius constellation. Big Ear utilised two feed horns to collect data from two different areas of Chi Sagittarii. Although it is unclear which horn actually found the signal, it picked up a signal with a signal-to-noise ratio peaking at 30, listed in the data as 6EQUJ5. The signal's recording occurred for 72 seconds before Earth's rotation moved Big Ear's horn to a different area of the sky. Therefore, the signal's actual duration remains unknown.

A few days later, astronomer and SETI volunteer Ehman analysed the data collected by Big Ear on 15th August. He was amazed by the signal's anomalous nature, writing "Wow!" next to the printout. To date, the Wow! signal has never been replicated, despite numerous attempts in the 1980s and 1990s. Its origins are a subject of intense debate; aside from the possibility that it may be an extra-terrestrial transmission, some scientists have put across alternative theories, including the idea that space debris merely reflected a signal that ultimately originated from Earth. Other hypotheses include the signal reflecting the hydrogen clouds of the 266P/Christensen and 335P/Gibbs comets, to a sun-like star within Sagittarius. As of the present day, the Wow! signal continues to both be unreplicable and seemingly unsolvable. Big Ear itself no longer exists, having been demolished in 1998 after its search was deemed by Congress to be a waste of taxpayer funds.

Availability

Ultimately, no audio tape of the signal exists. As noted by the Big Ear Radio Observatory memorial site, the telescope lacked audio recording equipment at the time it detected the signal. Thus, the 72 seconds of audio is now permanently missing, with the printout being the signal's only remnants. Several forgeries have been created claiming to be the Wow! signal. Among these included an audio file passed around video-sharing websites like YouTube as being audio from the signal. However, the file was debunked by YouTuber LOLZpersonok, who discovered that speeding up the file by 1,500% in Audacity revealed it was actually a recording of a police officer saying "10-61", a code meaning they are stopping a suspicious vehicle. Additionally, a common misconception is that The X Files episode "Little Green Men" utilised audio from the signal. In actuality, the sound used was produced by the show itself, and had no relation to the Wow! signal.

Videos

Wow! signal documentary.

Forgery claiming to be the Wow! signal.

LOLZpersonok debunking the above audio.