They called it The Bloop. Back in 1997, a group of marine scientists monitoring the Pacific Ocean recorded a sound no one had ever heard before. The scientists had encountered many odd noises before, but this sound, which lasted a minute and originated somewhere 1,500 miles off the coast of Chile, was the loudest unidentified underwater sound ever recorded. It was exponentially louder than a blue whale and, according to one of the scientists present, “it didn’t seem to be manmade.”

Watch this video from the Atlantic. Prepare to get goosebumps.

What did you think of this article?