The Bloop - an unidentified, ultra-low frequency sound

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The Bloop is an unidentified ultra-low frequency sound detected by NOAA in 1997, originating from the Pacific Ocean near Chile. Initially thought to be a potential biological phenomenon, it was later attributed to icequakes caused by the breaking of large ice shelves. Discussions surrounding the Bloop included speculation about its origins, with some suggesting it could be related to marine life or geological activity. The sound's characteristics have led to comparisons with biological calls, although definitive identification remains complex due to the nature of underwater acoustics. Despite the mystery being largely resolved, the Bloop continues to intrigue those interested in oceanic phenomena.
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Anyone heard/know it?

If so, what is your opinion? Real?
 
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No problem. I stumbled upon it while looking up info on the "Cloverfield" movie.

Pretty interesting.
 
There are recordings of "the bloop" here.
http://www.bloopwatch.org/thebloop.html

"The Bloop" is a mysterious and unexplained sound that was recorded by underwater microphones (hydrophones) in the Pacific Ocean in 1997. The sound was unusual because of its extremely low frequency and loud volume. It was detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) and was located near the remote South American island of Matías López off the southern coast of Chile.

The Bloop sound was notable for several reasons:

  1. Frequency: The sound had an extremely low frequency, estimated to be around 16 to 18 hertz. This is much lower than the sounds produced by known marine animals.
  2. Loudness: The Bloop was exceptionally loud and was detected by multiple hydrophones over a vast area of the ocean.
  3. Location: The sound appeared to originate from a remote part of the ocean, which added to the mystery.
For some time, the Bloop sparked various speculations and conspiracy theories. Some people suggested that it might be evidence of an undiscovered, massive sea creature or perhaps something even more mysterious.

However, in 2005, scientists identified the Bloop as most likely being the sound of a massive icequake or the cracking and breaking of a large ice shelf. When large pieces of ice break away from glaciers or ice shelves, they can produce sounds that travel through the water and are detected by underwater microphones. These icequakes can produce low-frequency sounds that resemble the Bloop.

While the mystery of the Bloop has been solved, it remains a fascinating historical curiosity that once stoked imaginations and speculations about unknown marine creatures lurking in the depths of the ocean.
 
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Sounds like a whale passing gas.
 
I'm trying to figure out why the NOAA website has speeded up the recording so much. It would make it very hard to identify anything. Then, the recording on the Wikipedia site seems to have been slowed down from the sped up version...not sure what is lost in that process.

Listening to the version on the NOAA website, it's impossible to tell much. The version on the Wiki site, which I'm not sure if it's an old version of the file before it was sped up, or if it's a slowed down version of the 16X recording on the NOAA site, sounds to me like there's more than one "voice." It seems to start out as a "solo" and then shortly, it seems like it jumps in volume and complexity as if another "voice" has joined, and then gets even louder like multiple "voices" are jumping in.

From the biological organism hypothesis, this makes sense if it's a pod of whales or something like that all joining in vocalizing, perhaps mating or feeding or alerting to predators.

I wonder how they determined the origin of the sound. For the sound to have traveled all the way from 50 degrees S to be audible on detectors near the equator is really impressive if that's some sort of sea creature vocalizing over that range.
 
I'm curious how they can be so certain that it was not just some type of sound made by plate movement, or a subterranean cavern collapse?
 
  • #10
Moonbear said:
I wonder how they determined the origin of the sound. For the sound to have traveled all the way from 50 degrees S to be audible on detectors near the equator is really impressive if that's some sort of sea creature vocalizing over that range.

I'd guess they triangulated its origin based on the data they received from more than one of the hydrophones that picked it up. Though I don't think they were *very* specific either, just giving latitude and longitude.

RonL said:
I'm curious how they can be so certain that it was not just some type of sound made by plate movement, or a subterranean cavern collapse?

The article in Damn Interesting noted it fit the profile of a biologically created call. I don't know exactly how that'd be determined, maybe using an algorithm to evaluate the waveform?
 
  • #11
RonL said:
I'm curious how they can be so certain that it was not just some type of sound made by plate movement, or a subterranean cavern collapse?

Earthquakes and underwater landslides etc are fairly common (think tsunami). As such there are probably a great many recorded events to compare it to. If it doesn't fit the sounds made by most of those then it's not unreasonable to think it might be something different. By knowing the epicentres of earthquakes and the speed of sound in water it'd be pretty easy to find a matching event- I wonder if this has been looked in to.
 
  • #12
I would be curious as to what all the submarine navys of the world have recorded with their millions of hours of undersea listening. I am sure all recordings of an undetermined nature are classified. I think there is more in the sea than we are aware of at this time.
 
  • #13
RonL said:
I'm curious how they can be so certain that it was not just some type of sound made by plate movement, or a subterranean cavern collapse?


[Scientist Christopher Fox of the U.S. National Oceanic and Atmospheric Administration's Acoustic Monitoring Project at Portland, Oregon] says:

"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,"

http://archives.cnn.com/2002/TECH/science/06/13/bloop/
 
  • #14
Speaking of the Bloop, I would like to bring your attention to the fact that there are some conspiracy theorists out there who proclaim that this Bloop was created by none other than Cthulu. Also, there are other unidentified sounds in the ocean. If you think the Bloop is creepy, check out Train, Julia, and especially Slowdown.

http://www.pmel.noaa.gov/vents/acoustics/sounds_mystery.html
 
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  • #15
Could it be a sea version of the Sarlacc in StarWars?
http://blogs.sanmathi.org/ashwin/wp-content/uploads/2007/07/sarlacc.jpg

According to HP Lovecraft, the ancient creatures in Cthulu lives "in between dimensions". Spend some time as young student to figure out what it meant by using generalized Fourier transforms of derivatives in n-dimension, especially between the dimensions like n=1.5. No tracks of Cthulu were found...

But seriously, why not some bio-gas eruption at the sea floor, where some huge cavity, comparable with the volume of the whales mouth or lung system emitting gas in portions by some kind of "mouth" which is brought in resonance (pressure while gas flow makes tension of the mouth but then tension in the membrane will force the mouth shut again and so on) to generate this kind of sound?
 
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  • #16
per.sundqvist said:
Could it be a sea version of the Sarlacc in StarWars?
http://blogs.sanmathi.org/ashwin/wp-content/uploads/2007/07/sarlacc.jpg

According to HP Lovecraft, the ancient creatures in Cthulu lives "in between dimensions". Spend some time as young student to figure out what it meant by using generalized Fourier transforms of derivatives in n-dimension, especially between the dimensions like n=1.5. No tracks of Cthulu were found...

Haha, as I started to read this my finger was twitching over the ban button. :biggrin:

Got me!
 
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  • #17
After listening to it, it definitely sounds biological. It being an ultra-low freq sound, it could have emanated from anywhere and just got trapped within the lower thermal layer and then traveled a very long distance. Some people think that whales dive down to that layer just so that they can communicate with others at great distances. Sounds usually tend to stay within their own thermal layer, but that involves the application of Snell's Law and the sounds angle, and there's way too many unknowns to even begin to try to figure anything out. All speculation.

If it is biological, I'm very surprised that we haven't detected more than just a few times. This makes me think that it could actually be something else. Possibly geological.
 
  • #18
I, and two other divers have heard something similar on a safety stop returning from a dive on in the Andaman Sea last November. At 5 metres, hanging in blue water, we all heard a loud and unmistakable 'Whooooo-ooooop'. This is how I described it in my log book. We were all experienced divers and none of us had heard anything like it before. I pointed to my ears at our dive guide/leader straight after the event and he raised both arms as if to say 'Search me!' On surfacing we discussed it further. We dismissed the idea of some sort of diver recall warning from another boat and couldn't come up with any explanation. Until I recently read reports of the '97 'Bloop', I had forgotten about it to be honest. At the time, all I can say is that it sounded like a sudden, immense release of gas/air, like a huge bubble hitting the surface- and before anyone makes any jokes, we were 'off-gassing' at the the time, but there is no way any of us could have made a noise as loud as that!
 
  • #19
I believe it is a robot like from the movie Transformers.
 
  • #20
Topfish90 said:
I, and two other divers have heard something similar on a safety stop returning from a dive on in the Andaman Sea last November. At 5 metres, hanging in blue water, we all heard a loud and unmistakable 'Whooooo-ooooop'. This is how I described it in my log book. We were all experienced divers and none of us had heard anything like it before. I pointed to my ears at our dive guide/leader straight after the event and he raised both arms as if to say 'Search me!' On surfacing we discussed it further. We dismissed the idea of some sort of diver recall warning from another boat and couldn't come up with any explanation. Until I recently read reports of the '97 'Bloop', I had forgotten about it to be honest. At the time, all I can say is that it sounded like a sudden, immense release of gas/air, like a huge bubble hitting the surface- and before anyone makes any jokes, we were 'off-gassing' at the the time, but there is no way any of us could have made a noise as loud as that!

What does experience have to do with something you've never encountered before?
 
  • #21
Mu naught said:
What does experience have to do with something you've never encountered before?

Because it works towards ruling out things it could be.

As a hypothetical example: an experienced diver who has heard the calls of every marine mammal out there, who hears a noise unfamiliar to him, can rule out all marine mammals as a source. See?
 
  • #22
DaveC426913 said:
Because it works towards ruling out things it could be.

As a hypothetical example: an experienced diver who has heard the calls of every marine mammal out there, who hears a noise unfamiliar to him, can rule out all marine mammals as a source. See?

sound logic.
 
  • #23
DaveC426913 said:
Because it works towards ruling out things it could be.

As a hypothetical example: an experienced diver who has heard the calls of every marine mammal out there, who hears a noise unfamiliar to him, can rule out all marine mammals as a source. See?

I was being a bit facetious, but I also don't think human testimony is worth the time to hear it. Sure an experienced diver may be familiar with certain sounds, but suppose he hears a whale make a sound he's never heard before; his experience would lead him to conclude "a whale could not have made that sound". Experience tends to make us less open to rational explanation - when we experience something beyond our normal experiences :wink:. At least this is my opinion.
 
  • #24
Mu naught said:
I was being a bit facetious, but I also don't think human testimony is worth the time to hear it. Sure an experienced diver may be familiar with certain sounds, but suppose he hears a whale make a sound he's never heard before; his experience would lead him to conclude "a whale could not have made that sound". Experience tends to make us less open to rational explanation - when we experience something beyond our normal experiences :wink:. At least this is my opinion.

You do make a good point. Venerable as those divers may be, it is weak evidence and really doesn't rule anything out. (Not that that's what he was suggesting it would do...)
 
  • #25
The best people to analyze this would not be divers, but sonar operators on a Boomer. I wonder if this could be infrasonic communication akin to what elephants manage, or if it could be an ULF "ping". Very odd.
 
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[i just heard one here in redding ca. at 10;10 sept 4th- freaked out our birds and horse ,lasted aprox.4 sec. no thunder ,checked rader.heard them before in klamath falls or. around 96 97 when we had big quakes.
 
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