WOW! A new study!

A remarkably strong and pure radio signal, lasting 72 seconds, prompted an astronomer to scrawl “Wow!” by hand on the printed readout. Now, decades later, a new study has reopened the case, suggesting that the signal may not have been just a simple “wow”, but one of the strongest pieces of evidence we’ve ever had of an alien civilisation. The “Wow!” signal stood out from any known terrestrial or natural source. It was incredibly strong, at a very specific frequency of 1420.4556 MHz - exactly the frequency of neutral hydrogen, a gas abundant in space. This frequency is protected by international agreements precisely because of its potential importance in interstellar communication. For decades, the signal’s origin remained a mystery. Some theories proposed it came from an aircraft, a satellite or even a comet, but none of these explanations was ever entirely convincing. A new study, conducted by the Arecibo Wow Project and led by Professor Abel Méndez, reanalysed the raw Big Ear data using modern signal processing techniques. The results were astonishing. The team not only confirmed the signal’s authenticity but also discovered that its strength had been vastly underestimated. The new analyses suggest the signal was four times more powerful than originally thought, reaching an intensity of 250 Janskys. Such power makes a terrestrial or ordinary natural origin even less likely. In addition to its intensity, the research identified two other faint but similar sources, dubbed “Wow2” and “Wow3”, which had been noted in the original records but never fully investigated. Although the new study doesn’t definitively solve the mystery, it puts forward a fascinating hypothesis: the signal could be the result of an astrophysical phenomenon such as a “super radiance event” or a “maser” from a small cold cloud of hydrogen. A maser is a natural microwave amplification phenomenon, similar to a laser but operating at radio frequencies. An event like this, possibly triggered by an intense radiation source such as a pulsar or magnetar, could explain the signal’s strength and nature. While some still believe in an alien origin, the new data and astrophysical hypotheses paint a more complex picture. What’s certain is that the “Wow!” signal remains one of the most compelling and intriguing clues in the history of the search for extraterrestrial life (SETI). The new findings reopen the case and pave the way for future targeted observations and studies - hoping that one day, “Wow!” will no longer be a question, but an answer.