New findings from astronomers may bring a fresh perspective on a signal that has confused the scientific community for over four decades. The infamous Wow! signal, first detected in 1977 by Ohio State University’s Big Ear radio telescope, has long intrigued astronomers as a potential sign of extraterrestrial life or an unknown cosmic phenomenon.
However, recent observations suggest a possible explanation to deepen our understanding of rare astronomical events.
In the 1970s, the Big Ear telescope was tasked with scanning the skies for anomalies, particularly those that might indicate extraterrestrial intelligence. On one fateful day in 1977, volunteer astronomer Jerry Ehman stumbled upon a 72-second signal so peculiar that he circled it on the printout and famously wrote “Wow!” beside it. This mysterious signal, now known as the Wow! signal has since captivated the imaginations of both the public and the scientific community.
Despite the advancements in radio astronomy over the years, no similar signals had been observed—until now. A research team led by Professor Abel Méndez of the University of Puerto Rico has identified multiple signals that bear a striking resemblance to the original Wow! signal, albeit 60-100 times weaker. These findings, though still pending peer review, could offer a breakthrough in our understanding of the signal’s origins.
Professor Méndez and his team unearthed these signals while analyzing data from the Arecibo Observatory, collected between 2017 and 2020. Their focus was on nearby red dwarf stars, including Teegarden’s Star, where they detected four intriguing signals. Unlike the original Wow! signal, these recent observations are believed to originate from interstellar clouds of cold hydrogen (HI) within our galaxy.
The Big Ear telescope had originally been searching near the 1420 MHz hydrogen emission line, often referred to as “the waterhole.” This frequency is considered a prime candidate for interstellar communication due to its relative quietness and hydrogen’s cosmic significance. Méndez’s team observed similar narrowband signals near this hydrogen line, although less intense than the Wow! signal.
Méndez speculates that the Wow! signal’s intensity could have been caused by a hydrogen cloud stimulated by a quick event, such as a magnetar flare. This hypothesis bridges a gap that has perplexed astronomers for years: how could such a narrowband signal, typically expected from alien communication, be produced by natural astronomical phenomena?
“Our signals from clouds could become brighter for minutes to hours due to a strong background radiation source,” Méndez states. This insight suggests that the Wow! signal may have been an extraordinary instance of an astronomical hydrogen maser flare—a phenomenon rarely observed and still not fully understood.
If this explanation holds, it could rewrite the narrative around the Wow! signal, not as an extraterrestrial message, but as a unique and valuable clue to the behavior of cold hydrogen clouds and the cosmic events that energize them.
While this revelation might disappoint those hoping for evidence of alien life, it provides astronomers with a new framework for interpreting similar signals in the future.
The findings from Méndez’s team are available as a preprint on ArXiv.org.