Deep Sounds

In Music at Night and Other Essays, novelist and philosopher Aldous Huxley wrote,

"After silence, that which comes nearest to expressing the inexpressible is music."

Anticipating near silence, marine acoustic oceanographers found music to their ears in the deepest point on Earth.

You would think that the deepest part of the ocean would be one of the quietest places on Earth. Yet there is almost constant noise.
— Robert Dziak, marine acoustics oceanographer

In an ocean trench deep enough to hide Mount Everest, scientists listened to natural and human-made sounds including baleen whale vocalizations and ship propellers.

Baleen whale by Nobu Tamura

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.
— Robert Dziak

Hydrophone lowered into
Challenger Deep

A hydrophone was lowered into the Challenger Deep trough — a depth of more than 7 miles. The ceramic hydrophone was encased in a titanium housing to withstand the great pressure at those depths.

The purpose of this 3-week data collection expedition was to establish a baseline acoustic level at depth. Some marine animals rely on sound to feed, navigate, and communicate.

Marine scientists hope to continue monitoring how growing levels of human-made sounds affect acoustically-sensitive marine life.

Silence will contain all the sounds,
All the words, all the languages,
All knowledge, all memory.
— Dejan Stojanovic

REFERENCES

• Music at Night and Other Essays, Aldous Huxley, 1931.
• Seven Miles Deep, the Ocean is Still a Noisy Place, NOAA, 2 March 2016.

Undersea Exploration in the Mariana Trench

The Mariana Trench
© MarianaTrench.com

The lowest place on earth is the Mariana Trench located in the western Pacific Ocean, to the east of the Mariana Islands.

Challenger Deep, the name given to the lowest point 35,756 feet below sea level, is located 300 miles south-west of Guam.

If the highest place on earth, Mount Everest, could be placed in the Mariana Trench, the peak of the mountain would be 7,166 feet below sea level.

All deep, earnest thinking is but the intrepid effort of the soul to keep the open independence of her sea, while the wildest winds of heaven and earth conspire to cast her on the treacherous, slavish shore.
~ Herman Melville

Filmmaker and National Geographic explorer-in-residence James Cameron descended 77 miles to Challenger Deep in a specially designed submersible, known as Deepsea Challenger, to record high-resolution 3D video and to collect samples on March 26, 2012. The expedition was chronicled for a 3D feature film.

Cameron spent hours on a desert-like seafloor collecting sediments and small sea creatures via robotic appendages to the submersible and measuring temperature, salinity, and pressure.

Exploration is really the essence of the human spirit.
~ Frank Borman

Samples and measurements from the Mariana Trench will be analyzed by a team of scientists.