Forbidden History - The Enigmatic ‘Wow!’ Signal

Episode Date: November 4, 2025

In this episode we delve into the mysterious story of the ‘Wow!’ signal. In 1977, a strong narrowband radio signal cut through cosmic noise at Ohio State University’s Big Ear Radio Observatory, causing the astronomer who discovered it to circle the data on the print out and scribble a single word, “Wow!” - could this communication have come from somewhere otherworldly?  Go to ⁠⁠⁠⁠⁠https://surfshark.com/forbiddenhistory⁠⁠⁠⁠⁠ or use code FORBIDDENHISTORY at checkout to get 4 extra months of Surfshark VPN! Go to ⁠nakedwines.co.uk/forbidden⁠ to get a £30 voucher and 6 top-rated wines for just £39.99, with delivery included. Cast List: Guy Walters: Author & Historian  Eric Meyers: Narrator  Learn more about your ad choices. Visit megaphone.fm/adchoices

Welcome to the Forbidden History Podcast. This program is presented solely for educational and entertainment purposes. It contains adult themes. Listener discretion is advised. For centuries, humanity has gazed upward, wondering if we are alone. The stars have inspired myth, religion, and science, but never an answer. In the late 20th century, we turned from gazing to listening. Massive radio telescopes scan the heavens, straining for the faintest murmur of another civilization.

And then, one summer night in 1977, the silence broke. The wow signal, it's an enigma, let's be frank, it is still a complete mystery. You know, this was a respected research project, it appears on an official readout. And if it is some sort of signal from an extraterrestrial, sentient living source, what it suggests is that there is intelligent life somewhere else in the universe. At Ohio State University's Big Ear Radio Observatory, a signal cut through the cosmic noise. It was so strong, so unusual, that the astronomer who discovered it circled the data on the printout and scribbled a single word.

Wow. Joining us for this story is historian Guy Walters. So what is the wow signal? I mean, why is it so famous? I mean, first of all, it's got a great name. And it was this very powerful and seriously unexplained radio signal which was detected by an astronomer called Jerry Eamon on August the 15th, 1977. Now, Jerry was working on a project called SETI, which stands for the search for extraterrestrial intelligence,

and this signal that he detected lasted for 72 seconds, and it came from the constellation Sagittarius near the M55 star cluster. The Big Ear Telescope was no ordinary dish. Built in 1956, it stretched across three eight years. acres of land in Delaware, Ohio, and for decades it swept the sky, searching systematically for signals. Unlike many telescopes that tracked objects, Big Ear stood still, allowing for the rotation of the Earth to scan the heavens.

This was so unusual that Jerry Eamon actually circles the printout, and he writes the word, and that's what gives it its really famous name. There have been numerous attempts to try and detect and pick up this signal, but it's never been heard again. What set this transmission apart was not only its strength, but its frequency. 1420 megahertz. This wasn't random static. It was tuned to a channel that has cosmic significance.

And now what we know about that frequency is that it's the natural emission frequency of hydrogen. And of course, hydrogen is the most abundant element in the universe. Now, that makes it of interest to astronomers because it's considered a logical choice. If you are an extraterrestrial civilization, and if you are attempting some form of interstellar communication, if you are trying to reach out for other life forms, that's the frequency you're going to choose. Hydrogen forms the backbone of stars and galaxies. If intelligent life wanted to pick a universal channel, one any advanced civilization could recognize, this was it.

And that's what made the wow signal so hard to dismiss. And what's also interesting is that the wow signal is much stronger than mere background noise. You know, and that seems to suggest that this isn't just some random cosmic event, but actually it's a clear and intentional source. Pinpointing the origin of the signal, however, proved annoyingly difficult. The Big Ear Telescope's design meant it could only say the signal came from one of two nearby points in the constellation Sagittarius. Neither contained a known radio source.

So as a result, there are no known celestial objects in that region that emit, signals of this nature and that really adds to the mystery. But it's really hard with that telescope used back at the time to absolutely pinpoint it exactly. So that again adds to the mystery. Two points of sky, billions of stars behind them and no obvious culprit. It was like receiving a phone call, but not knowing which house on the street it came from. Scientists have always insisted on caution. A single signal, however exciting, cannot be taken as proof of alien life. Many possible explanations have been put forward, ranging from the mundane to the exotic. While there are quite a few people out there who say that wow signal has to be made by

some form of extraterrestrial civilization, there are plenty of scientists who go, hang on a minute, there are plenty of natural explanations for this. So one thing it could be is some form of emissions from a passing comet. It could be what's known as an interstellar scintillation. Or it could simply be reflections coming off space debris, space junk, i.e. stuff that men have put up there. In 2017, a new hypothesis emerges. And this suggests a signal could have come from a hydrogen cloud surrounding a then unknown comet.

However, you know, a lot of people think, I don't really buy that. Let's challenge that. because, you know, we know what the emissions from comets are like, and the characteristics of the wow signal don't really match it. Other theories invoke satellites, or even military transmissions that had slipped into the telescope's beam. But each explanation had cracks. Comets don't line up. Sintillation doesn't produce such a clean, narrow frequency, and man-made interference has fingerprints that weren't present in the day.

The wow signal remained stubbornly unique. So no plausible natural explanation has really conclusively accounted for the sort of real singularity of the wow signal and also its strength. And this is why Jerry wrote the word wow. But if it wasn't natural, could it have been human error or worse, a hoax? You know, this was a respected research project. It appears on an official readout. You know, it's really unlikely to be a hoax. And I think that would really besmirch Mr. Eammon and big time.

Also, I think that equipment malfunction, I think that's highly unlikely because what we do know is that that observatory, the great-named Big Ear Radio Observatory, that had been working absolutely fine, completely successfully, for years. The Big Ear had cataloged thousands of radio sources with flawless accuracy. And Jerry Eamon himself, a meticulous scientist, gained nothing from faking a discovery. If the wow signal was an error, it was one that has never been repeated before or since. We'll be right back after a short ad break.

Now, obviously, there's an obvious question. Has SETI, you know, that search for extraterrestrial intelligence, Has it found any similar signals to wow? You know, any little wows, if you like. In the decades that followed, SETI detected many strange bursts and tones. Each was investigated and everyone turned out to have an earthly explanation. Satellites, radar, even microwave ovens at observatories. SETI has detected a lot of unexplained signals,

but none have matched WOW's intensity and characteristics. Some of these signals, you know, they cause a little flurry of interest and they look promising, but they're later identified as really quite boring things like terrestrial interference or natural cosmic phenomena. We've got now since the WOW signal, you know, huge advances in technology and many more powerful telescopes and they're scanning the sky all the time. Data crunching is so much better now with computing power. But as of yet, not since Wow has any signal given us any compelling evidence of extraterrestrial intelligence.

There have been other contenders. In 2019, a signal dubbed BLC1 appeared to come from Proxima Centauri, the closest star to the sun. For weeks it made headlines, but in the end it was traced back to human interference. The wow signal remains unmatched in official, recognized evidence of potential alien contact. But what about the more unofficial? Just one year before 1976, the young Mexican pilot named Rafael Pacheco Perez was flying a routine training mission. What should have been an uneventful flight quickly descended into something chilling. It is alleged Perez vanished from radar, only to reappear later over Acapulco,

with a full fuel tank, no memory of what had happened, and one disturbing detail. During his disappearance, air traffic control reported that a strange voice had taken over his radio. The voice claimed it was using the pilot as a microphone. Perez had no memory of the incident, or what was said. But the ground crew listening claimed that statements included, We don't matter much, nor where we come from, nor where we're going. Just know that we are beings from this universe to which you belong. Our planet is many light years away.

We are physically the same as you. I repeat, all races. in the universe are physically the same. You are not alone in the universe, and there are other races that we are keeping away from you, but we are watching you. The controller also noted that the voice responded fluently in English and German, despite the pilot's lack of fluency in those languages. Could it be that the mysterious voice that commandeered Perez's radio in 1976, claiming to use him as a microphone and the unexplained wow signal detected just a year later, were not isolated events at all,

but fragments of the same transmission, reaching us through different channels? Could it mean that they're attempting to communicate with Earth? Is it a deliberate attempt? Is it an accidental attempt? Is this civilization if it exists? Are they just sending stuff out broadcasting signals in every direction, you know, in the hope they might reach other civilizations? Or are they just literally pinpointing a highly directional signal

and it happens to go through our bit of space? Is it a greeting? Is it a test or, you know, or is it some sort of attempt at a scientific collaboration across the cosmos? If deliberate, the message was heartbreakingly brief. If accidental, we may never know what it truly meant. Despite the odds, however, the search hasn't stopped. In 2015, the Breakthrough Listen Project was launched

with $100 million of funding, the largest effort in SETI's history. Using the Green Bank Telescope in West Virginia and Parks Observatory in Australia, It surveys over a million stars across billions of frequencies. And that's continuing to monitor the sky for signals really similar to wow. And obviously what they're using are far more advanced radio telescopes than back in those days. Every day it collects more raw data than the big ear gathered in its entire lifetime. And then what you've also got are researchers.

They're going through the old data and they're using AI techniques to try and identify patterns that may have been overlooked by the old technology. Machine learning now scours these archives, searching for hidden anomalies that the human eye might have missed. You've also got a lot of new efforts that are being made to target the same region of space, but with much more high sensitivity instruments. And hopefully these may yield some new insights, but you know, for now, the wow, it still remains a total astronomical history.

Beyond Breakthrough Listen, other programs are widening the net. NASA's test spacecraft, launched in 2018, is scanning nearby stars for planets in the so-called habitable zone. These are worlds where liquid water could exist. By identifying thousands of these candidates, astronomers are narrowing the list of places most likely to harbor life. On the ground, observatories like the Allen Telescope Array in California are dedicated solely to the hunt for intelligent signals.

With dozens of dishes working in unison, it can scan multiple star systems at once. A level of coverage, Jerry Eamon and the Big Ear Team, could only dream of. Then there is the search not for radio, but for techno signatures, indirect evidence of Alien technology. Astronomers are studying the brightness of distant stars, looking for irregular dips in light that might suggest colossal structures, likely hypothesized Dyson spheres, megastructures built to capture starlight. The event remains the most tantalizing unsolved moment in the history of SETI. The wow signal, it's an enigma, let's be frank. It is still a complete mystery, you know, and unless there's another detection of it, we may never explain it. And if it is some

sort of, you know, signal from an extraterrestrial, sentient living source, an actual ET, what it suggests is that there is intelligent life somewhere else in the universe. But the wow signal as it stands is not evidence enough. We need more evidence, clearly. Whether it's a product of aliens or just some weird cosmic event we don't understand. That wow signal, I think, is a real inspiration. Because I think searching for life beyond Earth is something we're kind of duty-bound to do as humans. And I think we should always be curious about what's out there in clearly what is a very big place, the universe. For Jerry Eamon, it was a string of numbers on a printout.

For science, it was a challenge. And for humanity, it remains a whisper from a... across the galaxy. A whisper we may spend centuries trying to hear again. Thanks for exploring the past with us today. If you like this episode, please be sure to follow for more. We post new episodes every Tuesday and Thursday. Don't forget to leave a comment below and feel free to leave us a rating or review. Your feedback helps us reach more listeners like you. And for more from the Like a Shot Network. Check out Where Did Everyone Go, Histories of the Abandoned, a deep dive into the incredible stories behind forgotten places.

Available now on your favorite podcast platforms. Thanks for listening.