A new octopod species discovered 14,000 feet deep in the Hawaiian Archipelago (image not connected to the Challenger Deep mission). NOAA

A mission seven miles down reveals a surprisingly raucous soundscape.

Plunge to the most abysmal reaches of the ocean, roughly seven miles down in the Mariana Trench’s Challenger Deep trough, and what do you hear? Groaning behemoths, seismic rumbles, and yes, even the noise of ships far above churning the waves.

This surreal soundscape is now ours to trance out to thanks to scientists at NOAA and elsewhere, who dropped a microphone 36,000 feet down in the seas near Micronesia. Here’s some of what they noted during three weeks of monitoring, according to NOAA:

“You would think that the deepest part of the ocean would be one of the quietest places on Earth,” said Robert Dziak, a NOAA research oceanographer and chief project scientist. “Yet there is almost constant noise. 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.”

The hydrophone also picked up sound from ship propellers. Challenger Deep is close to Guam, a regional hub for container shipping with China and the Philippines.

The scientists eavesdropped using a special, titanium-armored mic that wouldn’t implode under the trench’s pressure of 16,000 PSI (sea-level pressure is around 15 PSI). They hope the recordings will help establish a baseline reading for oceanic clamor—important because increasing noise from human sources like ship engines and sonar has possible harmful effects on marine life.

NOAA

The expedition had some unreal moments, such as when the researchers detected the booms of a magnitude 5.0 earthquake below the quake itself. There was also this lonesome baleen-whale call that sounded like a man being punched in the groin in slow motion:

The scientists have shared photos and an auditory sampling of the Mariana Trench here; these are a couple more examples of the commotion at the fathomless deep. This is a ship’s propeller passing overhead:

And this duet was composed by a whale singing before and during that earthquake:

About the Author

Most Popular

  1. Videos

    5 Ways to Seriously Battle Traffic

    So long as cars are among us, road pricing, ramp meters, and diamond-shaped intersections can mitigate horrendous commutes, a new video explains.

  2. The Salk Institute, near San Diego
    Design

    This Is Your Brain on Architecture

    In her new book, Sarah Williams Goldhagen presents scientific evidence for why some buildings delight us and others—too many of them—disappoint.

  3. Transportation

    Do Driverless Cars Need Their Own Roads Around Manhattan?

    A concept for AV expressways promises to reduce travel times, but falls into an old trap of car-centric planning.

  4. An empty storefront on a sidewalk with a "retail space for lease" sign in the window
    Life

    How Cities Can Save Small Shops

    Some places are already taking action, but New York City is lagging behind. Here’s a blueprint for keeping local retail healthy.

  5. Transportation

    5 Reasons to Be Wary of Elon Musk's Hyperloop

    High-speed vactrains might be the ticket for a Martian colony. As a practical transit investment for Earth, the technology has a long way to go.