From DeFacto Sound, you're listening to 20,000 Hertz,

the stories behind the world's most recognizable

and interesting sounds.

I'm Dallas Taylor.

This is the story of what sound is like underwater.

The sound you just heard is one of the most mysterious underwater sounds we know of.

It's called The Bloop.

It was recorded in 1997, and it's unbelievably loud.

The sound was roughly triangulated to be coming from a remote region of the

Southern Pacific Ocean, just west of the tip of South America. The microphones that captured

the sound were over 3,000 miles away. Could it be a massive, undiscovered monster from the deep?

Researchers are still discovering new aquatic life every year.

But this sound was several times greater than even the loudest animal in the world,

the blue whale.

Noah, the National Oceanic and Atmospheric Administration, now believes it was an icequake,

or an iceberg scraping the ocean floor.

Or was it?

The world's oceans cover 71% of the Earth's surface.

And while there are a few areas of land that have yet to be explored by mankind, that's nothing.

Almost 95% of the oceans have never been seen by human eyes.

It's like an alien planet, but it's Earth.

The Bloop is only one of the many mysterious, possibly unexplainable underwater sounds.

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