Scientists send a microphone into the Mariana Trench, and find it’s surprisingly noisy down there


It’s the lowest point on the our planet–the Mariana trench. A crack that extends about 36,000 feet (about 10.9Km) beneath the surface of the ocean, the bottom of all that water translating into a pressure amounting to a numbing 16,000 psi (about 1.2 tons per square foot.) So in such desolate an area–one that’s not likely to have a scene that’s teeming with life–it’s bound to be really, really quiet right?

Actually quite the opposite–the deepest part of the ocean, as scientists from the US National Oceanic And Atmospheric Administration (NOAA) discovered, is rife with all kinds of sounds ranging from ships passing overhead, to whales moaning as they swim by, to even distant earthquakes being captured.

Scientists launched the experiment to help establish a baseline noise level for the ocean in order to aid in studies around the effect that man-made noise pollution is having on oceanic life. The experiment consisted of dropping a specially designed titanium-armored microphone that could withstand those great pressures.

After recording sounds for about 23 days (then making its way back to the scientists only four months later when the weather allowed ships to retrieve it,) scientists were amazed to be treated to surreal aureal findings–it was far more clamorous that they ever expected it to be.

“There’s almost constant noise,” said Robert Dziak, a NOAA research oceanographer and the chief project scientist. “The ambient sound field is dominated by the sound of earthquakes, both near and far, as well as distinct moans of baleen whales, and the clamor of a category 4 typhoon that just happened to pass overhead.”

Here, for example of a clip of a passing whale, followed by a 5.0 Richter earthquake that was captured (note that the sound is actually recorded from beneath the source of the earthquake!)