Ever since the first hydrophones were invented back in the early 20th century, we have been listening to the world’s oceans for everything from enemy submarines to the creatures that dwell within it and the even earth itself so we can better understand its internal structure. However, in 1997, the U.S. National Oceanic and Atmospheric Administration (NOAA) would record a sound unlike any they (or anyone else for that matter) had ever heard before. The loudest underwater sound ever recorded.
The extraordinary sound they heard that day would quickly be dubbed ‘The Bloop’. This onomatopoeic oddity would only last for a minute, beginning as a low rumble before rising in frequency. It wasn’t just its detection that would shock researchers, it would be its intensity and the fact that it was recorded by underwater microphones more than 5,000 kilometers (3,000 miles) away in a remote point in the south Pacific Ocean west of the southern tip of South America.
The NOAA Vents Program believe it has the answer and has attributed the mysterious sound to that of a large cryoseism (otherwise known as an ice quake), postulating that the sound of this disintegrating iceberg most likely originated somewhere between the Bransfield Straits and the Ross Sea or possibly at Cape Adare, all of which are close to Antarctica. Not everyone agrees with this conclusion and some have come up with a different and prodigious alternative.