[xoxoxoBruce]

The Spectrogram of the BloopDuring the Cold War, the United States Navy erected a vast array of underwater listening devices in order to detect and track Soviet nuclear submarines. These hydrophones were placed at roughly 3,000 mile intervals in the deep layer of water known as the deep sound channel, where cold temperatures and high pressures allow sound waves to propagate great distances. When the Cold War ended, rather than mothballing the Sound Surveillance System (SOSUS), the U.S. Navy lent the Cold War relic to science.

The array has since been used to track many fascinating undersea events, such as whale migrations, earthquakes, ocean currents, volcanic activity , and the shifting of Antarctic ice. But one sound captured by the sensitive SOSUS hydrophones has scientists puzzled. It fits the profile of a living creature, but for a creature to create this sound it would have to be significantly larger than a blue whale, which is believed to be the largest animal ever to have lived.

The rest of this article at damn Interesting.

It's got to be quite a bloop to be heard 3000 miles away, in several directions. And if it's a critter, it's huge.