What was 'The Bloop?' It was a name given to an ultra-low frequency and extremely powerful underwater sound detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) several times during 1997. According to the NOAA description, it "rises rapidly in frequency over about one minute and was of sufficient amplitude to be heard on multiple sensors, at a range of over 5,000 km. The source of the sound remains unknown..."
During the Cold War, the United States Navy erected a vast array of underwater listening devices in order to detect and track Soviet nuclear submarines. These hydrophones were placed at roughly 3,000 mile intervals in the deep layer of water known as the deep sound channel, where cold temperatures and high pressures allow sound waves to propagate great distances. When the Cold War ended, rather than mothballing the Sound Surveillance System (SOSUS), the U.S. Navy lent the Cold War relic to science.
The array has since been used to track many fascinating undersea events, such as whale migrations, earthquakes, ocean currents, volcanic activity , and the shifting of Antarctic ice. But one sound captured by the sensitive SOSUS hydrophones has scientists puzzled. It fits the profile of a living creature, but for a creature to create this sound it would have to be significantly larger than a blue whale, which is believed to be the largest animal ever to have lived.
The unexplainable sound was detected off the South American southwest coast at about 50° S 100° W. Perplexed researchers, unable to identify any possible source for the sound, dubbed it 'The Bloop.'
The sound shares many characteristics with those emanated from biological creatures, in fact it fits those parameters so closely that a large number of researchers are convinced that its origin is animal. NOAA statement: "Scientists determined that its wave pattern indicates it was made by an animal, and not a giant electromagnet sucking a plane out of the sky, as the creators of 'Lost' were no doubt hoping." But in order for an aquatic animal to emit a sound that can travel over 3,000 miles though Earth’s noisy oceans, scientists say that it would need an incredibly large noise-making apparatus, one much bigger than that of the blue whale. NOAA statement: "While the audio profile of the bloop does resemble that of a living creature, the system identified it as unknown because it was far too loud for that to have been the case: it was several times louder than the loudest known biological sound."
Theories abound as to the source of 'The Bloop.' If it is the vocalization of a living organism, it is one which makes its home in the dark, cold depths of the ocean. Some have suggested that giant squids could be responsible for the sound, but that is unlikely considering that no known species of cephalopod have the gas-filled sac necessary to reach such great volumes. Indeed science has not recorded any animals, living or extinct, with nearly enough size to house the organs needed to produce the level of output demonstrated by 'The Bloop'...so unless this mystery creature uses some unknown mechanism to generate sound, it is presumed to be an incredibly massive organism.
BTW, the roughly-triangulated origin of 'The Bloop' is approximately 950 nautical miles (1,760 km) from the more precisely-described location of R'lyeh, a sunken extra-dimensional city written of by H.P. Lovecraft in his short story The Call of Cthulhu. There has been speculation that the creature from J.J. Abrams' Cloverfieldwas based on the Cthulhu in Lovecraft's tale.
Click for video - The Bloop: A Mysterious Sound from the Deep Ocean | NOAA SOSUS
Link to audio file - "The Bloop", a noise recorded by the NOAA in 1997
CNN article from June 13, 2002
Tuning in to a deep sea monster
Scientists have revealed a mysterious recording that they say could be the sound of a giant beast lurking in the depths of the ocean.
Researchers have nicknamed the strange unidentified sound picked up by undersea microphones "Bloop."
While it bears the varying frequency hallmark of marine animals, it is far more powerful than the calls made by any creature known on Earth, Britain's New Scientist reported on Thursday.
It is too big for a whale and one theory is that it is a deep sea monster, possibly a many-tentacled giant squid.
In 1997, Bloop was detected by U.S. Navy "spy" sensors 3,000 miles apart that had been put there to detect the movement of Soviet submarines, the magazine reports.
The frequency of the sound meant it had to be much louder than any recognised animal noise, including that produced by the largest whales.
So is it a huge octopus? Although dead giant squid have been washed up on beaches, and tell-tale sucker marks have been seen on whales, there has never been a confirmed sighting of one of the elusive cephalopods in the wild.
The largest dead squid on record measured about 60ft including the length of its tentacles, but no one knows how big the creatures might grow.
For years sailors have told tales of monsters of the deep including the huge, many-tentacled kraken that could reach as high as a ship's mainmast and sink the biggest ships.
However Phil Lobel, a marine biologist at Boston University, Massachusetts, doubts that giant squid are the source of Bloop.
"Cephalopods have no gas-filled sac, so they have no way to make that type of noise," he said. "Though you can never rule anything out completely, I doubt it."
Nevertheless he agrees that the sound is most likely to be biological in origin.
The system picking up Bloop and other strange noises from the deep is a military relic of the Cold War.
In the 1960s the U.S. Navy set up an array of underwater microphones, or hydrophones, around the globe to track Soviet submarines. The network was known as SOSUS, short for Sound Surveillance System.
The listening stations lie hundreds of yards below the ocean surface, at a depth where sound waves become trapped in a layer of water known as the "deep sound channel".
Here temperature and pressure cause sound waves to keep travelling without being scattered by the ocean surface or bottom.
Most of the sounds detected obviously emanate from whales, ships or earthquakes, but some very low frequency noises have proved baffling.
Scientist Christopher Fox of the U.S. National Oceanic and Atmospheric Administration's Acoustic Monitoring Project at Portland, Oregon, has given the signals names such as Train, Whistle, Slowdown, Upsweep and even Gregorian Chant.
He told New Scientist that most can be explained by ocean currents, volcanic activity -- Upsweep was tracked to an undersea South Pacific mountain that had not been identified as "live."
"The sound waves are almost like voice prints. You're able to look at the characteristics of the sound and say: 'There's a blue whale, there's a fin whale, there's a boat, there's a humpback whale and here comes and earchquake," he says.
But some sounds remain a mystery he says. Like Bloop -- monster of the deep? - CNN
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