A dedicated amateur astronomer has reignited the debate over the enigmatic 'Wow!' signal, detected in the U.S. more than 45 years ago. His analysis points to a Sun-like star in the exact region from which the signal originated.
On August 15, 1977, at Ohio State University's Big Ear radio observatory, SETI researcher Jerry Ehman made a groundbreaking observation. While scanning stars in the Sagittarius constellation at 11:16 p.m., he spotted a 72-second burst at 1.42 GHz—over 30 times stronger than background noise. No prior signal matched it. Ehman circled it on the printout and scribbled "Wow!" beside it.
For decades, the signal's source puzzled experts, with many hypothesizing it as a possible extraterrestrial transmission. Its frequency aligns closely with the hydrogen line (1420 MHz), a logical choice for interstellar communication. This real event even inspired the plot of José Rodrigues dos Santos's acclaimed novel Signe de vie, which I highly recommend.
In 2017, astronomer Antonio Paris from St. Petersburg College, Florida, proposed a natural culprit: comet 266P/Christensen. Its vast hydrogen cloud, spanning millions of kilometers, could have emitted the signal. Trajectory data confirmed the comet's proximity to Earth at the time.
Paris published in the Journal of the Washington Academy of Sciences, seemingly resolving the mystery. However, Ohio State researchers swiftly refuted it: the comet was 15 degrees off the signal's position, lacked spectral matches, and didn't appear in both of the telescope's beams.
Now, amateur astronomer Alberto Caballero has analyzed ESA's Gaia database of 1.3 billion stars, targeting Sun-like candidates in the signal's origin zone. His finding: "2MASS 19281982-2640123, the only potential Sun-like star in the entire Wow! signal region."
Though too distant for a timely reply signal, Caballero suggests it's an ideal target for exoplanet hunts. The 'Wow!' signal's origin remains unsolved—but targeted observations could yield breakthroughs.
