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 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 emanating 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 for an aquatic animal to emit a sound that can travel over 3,000 miles through 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 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.
Further study of 'The Bloop' is hampered by the fact that it has not been heard since the summer of ’97. It is almost certain that unseen creatures still lurk in the deep and dark oceans, creatures that are strange and fascinating. Such an unknown animal may have uttered these sounds while lingering at an unusually shallow depth. Unless researchers encounter the sound again, there is little chance that we’ll have any explanation more concrete than scientific speculation. But given its unusual properties and strong indications of a large biological origin, it makes for a compelling mystery.
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 by H.P. Lovecraft in his short story The Call of Cthulhu. There has been speculation that the creature from J.J. Abrams' Cloverfield was 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 recognized 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 is 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 in 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, and 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 an earthquake," he says.
But some sounds remain a mystery he says. Like Bloop -- monster of the deep?
-----
UPDATE: from Wired.co.uk:
Has 'The Bloop' Been Solved?
"....the NOAA is pretty sure that it wasn't an animal, but the sound of a relatively common event -- the cracking of an ice shelf as it breaks up from Antarctica. Several people have linked to the NOAA's website over the past week excitedly claiming that the mystery of the Bloop has been "solved", but as the information on the NOAA website was undated and without a source, Wired.co.uk spoke to NOAA and Oregon State University seismologist Robert Dziak by email to check it out. He confirmed that the Bloop really was just an icequake -- and it turns out that's kind of what they always thought it was. The theory of a giant animal making noises loud enough to be heard across the Pacific was more fantasy than science.
Dziak explained to us the NOAA's findings, and confirmed that "the frequency and time-duration characteristics of the Bloop signal are consistent, and essentially identical, to icequake signals we have recorded off Antarctica". He explained: "We began an acoustic survey of the Bransfield Strait and Drake Passage in 2005 which lasted until 2010. It was in analysis of this recent acoustic data that it became clear that the sounds of ice breaking up and cracking is a dominant source of natural sound in the southern ocean. Each year there are tens of thousands of what we call 'icequakes' created by the cracking and melting of sea ice and ice calving off glaciers into the ocean, and these signals are very similar in character to the Bloop."
That makes it "extremely unlikely" that the sound is animal in origin, but he also pointed out that the hypothesis that the Bloop was caused by an animal wasn't ever really a serious one. He said: "What has led to a lot of the misperception of the animal origin sound of the Bloop is how the sound is played back. Typically, it is played at 16 times normal speed, which makes it sounds like an animal vocalisation of some sort. However, when the sound is played in real-time it has more of a 'quake' sound to it, similar to thunder." You can hear a recording of the Bloop in the video accompanying this story...."
NOTE: Are you buying this explanation? Lon
Sources:
damninteresting.com
slightlywarped.com
physicsforums.com
unexplained-mysteries.com
forum.lostpedia.com
CNN.com
science.org.au
wired.co.uk
*****
*****
Bigfoot and Other Cryptid Videos on YouTube
'KILLER BIGFOOT' HUNTED BY U.S. SPECIAL FORCES / GLIMMER MAN / MANTIS HUMANOIDS
'DOGMAN IN OUR YARD!' - AN OHIO FAMILY'S 12-YEAR SAGA WITH CRYPTID CANINES
-----