Nearly 11 kilometers deep, the ocean is still a noisy place, according to scientists that have eavesdropped on the deepest part of the world's ocean, and instead of finding a sea of silence, discovered a cacophony of sounds both
natural and caused by
humans.
For three weeks, a titanium-encased
hydrophone recorded constant ambient noise from the ocean floor at a depth of more than 36,000 feet, or 7 miles, in the
Challenger Deep trough in the
Mariana Trench near Micronesia. 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.
