The signal that made scientists say WOW!
On August 15, 1977, astronomer Jerry Ehman detected a strange signal while working on a SETI project at Ohio State University’s Big Ear radio telescope. The 72-second sequence featured an unusual intensity, prompting Ehman to circle the letter code 6EQUJ5 in a printout and write “WOW!” in the margins. This code, which describes the intensity variation of the narrow radio signal, appeared to come from a globular cluster in the constellation Sagittarius. The source of the signal was never determined, leading to speculation that it came from aliens. Research from 2016 suggested the signal was produced not by aliens, but a hydrogen cloud caused by comets.
