The Mariana Trench, the deepest part of the ocean, is one of the most mysterious aspects of our planet.
Stretching down to 6.7 miles below sea level at its deepest point, known as Challenger Deep, the trench has all the pressure of the vast Pacific Ocean crushing down on it. It’s extremely difficult to explore, and very little is known about what sea life survives down there.
However, some clever scientists have sent a hydrophone recording device with a titanium-encased microphone down there for three weeks to capture the sounds of the Challenger Deep, and the noisiness has shocked them.
A near-constant cacophony of murky rumbles and moans can be heard, sounding almost like an ambient sound art experiment. It’s both unsettling and beautiful.
As NOAA research oceanographer Robert Dziak said: "You would think that the deepest part of the ocean would be one of the quietest places on Earth, yet there really is almost constant noise from both natural and man-made sources."
Listen to some of the sounds below.
A ship propellor passing 6.7 miles overhead:
A magnitude 5 earthquake near Guam, Micronesia on July 16, 2015:
A baleen whale's calls right before and after the same quake: