The Wow! Signal

This episode explores the mystery of the Wow! Signal, a powerful and unexplained radio transmission detected on August 15, 1977, by the Big Ear radio telescope in Ohio. The signal lasted 72 seconds, appeared at the hydrogen line frequency (1420 MHz) — considered ideal for interstellar communication — and originated from the direction of the Sagittarius constellation. Astronomer Jerry Ehman famously circled the signal on a printout and wrote “Wow!”, giving the event its name. Despite repeated attempts, the signal was never detected again, and no confirmed natural or human-made source has been identified. Proposed explanations include rare cosmic phenomena, human interference, comets, or the possibility of an intentional extraterrestrial transmission. None have been proven. Nearly fifty years later, the Wow! Signal remains one of the most compelling moments in the search for extraterrestrial intelligence — a brief whisper from the cosmos that may have been chance… or contact… before falling silent forever.