‘Wow’: Scientists may have received an alien message from space, but what does it mean? Produced by: Tarun Mishra Designed by: Manoj Kumar Discovery of the “Wow!” Signal On August 15, 1977, Ohio State University’s Big Ear Radio Telescope detected a strong narrow-band radio signal during a search for extraterrestrial intelligence (SETI). The signal lasted 72 seconds and was so noteworthy that astronomer Jerry Ehman wrote “Wow!” on the printout, giving the signal its name. Direction and Origin The signal originated from the direction of the constellation Sagittarius. It is considered one of the best candidates for an alien radio transmission due to its intensity and duration. Ongoing Search for the Source Despite extensive efforts, the exact source of the “Wow!” signal has not been identified. This has led to various theories about its origin, with no definitive conclusion. Theories of Natural Cosmic Events Some scientists propose that the signal might have been a natural cosmic event or interference from a terrestrial source. However, no specific natural source has been confirmed. Possibility of Extraterrestrial Origin The hypothesis that the “Wow!” signal could be a message from an extraterrestrial civilization remains a subject of interest. Recent research points to a Sun-like star 1,800 light-years away as a possible source, though this is not confirmed. Characteristics of the Signal The “Wow!” signal was concentrated on the hydrogen line at a wavelength of 21.106 cm and a frequency of 1420.406 MHz, emitted by hydrogen atoms, the most common element in the universe. Comet Theory In 2016, Antonio Paris suggested that the signal could have been caused by a hydrogen cloud accompanying one of two comets, 266P/Christensen and P/2008 Y2, present in the same region of the sky. This theory remains controversial. Follow-Up Observations In 2017, Paris and his team observed Comet 266P/Christensen and found its signal matched the “Wow!” signal. However, some astronomers argue this explanation does not fully account for the signal’s characteristics. Cultural Impact The “Wow!” signal has influenced popular culture, including its integration into the Netflix series ‘3 Body Problem,’ based on Liu Cixin’s science fiction trilogy. The series portrays the signal as a real message from an alien civilization. Unresolved Mystery The “Wow!” signal remains an unsolved mystery in the search for extraterrestrial intelligence. Researchers continue to explore potential natural and extraterrestrial explanations. Until a repeat signal is found or a definitive explanation is provided, the “Wow!” signal will continue to be a subject of investigation and speculation. Related Stories