One of the most famous events in the history of astronomy is the Wow! Signal that was picked up by Ohio State University’s Big Ear radio telescope in August 1977. The signal entered folklore because it couldn’t be explained by any known natural phenomena and didn’t appear to have originated from Earth.
That left open an extraordinary possibility: that it had been produced by an extraterrestrial civilization. Indeed, Jerry Ehman, the astronomer who noticed the signal in the data, was so shocked by it that he wrote “Wow!” on the data print out, which is how it got its name.
Since then, various astronomers have trained their telescopes on the same part of the sky in the constellation of Sagittarius looking for a repeat or some clue to its origin. But none of these studies has found anything unusual; so the mystery has never been solved.
