The Bloop - an unidentified, ultra-low frequency sound


by Rocket254
Tags: bloop, frequency, sound, ultralow, unidentified
Rocket254
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#1
Jan26-08, 10:34 PM
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Anyone heard/know it?

If so, what is your opinion? Real?
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Ivan Seeking
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Jan26-08, 10:40 PM
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The Bloop is the name given to an ultra-low frequency underwater sound detected by the U.S. National Oceanic and Atmospheric Administration several times during the summer of 1997. The source of the sound remains unknown. [continued]
http://en.wikipedia.org/wiki/Bloop

It appears to be on the level.
http://oceanexplorer.noaa.gov/explor...ml#Anchor-1515

Thanks. I had never heard of this before.
Rocket254
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#3
Jan26-08, 10:53 PM
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No problem. I stumbled upon it while looking up info on the "Cloverfield" movie.

Pretty interesting.

Mech_Engineer
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Jan28-08, 10:02 AM
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The Bloop - an unidentified, ultra-low frequency sound


One of the greatest websites ever to grace the internet has an article on it:

http://www.damninteresting.com/?p=517#more-517
Ivan Seeking
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Jan28-08, 11:51 AM
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This has been added to our list of credible anomalies.
http://www.physicsforums.com/showthread.php?t=58374
glondor
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#6
Feb4-08, 05:51 PM
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There are recordings of "the bloop" here.
http://www.bloopwatch.org/thebloop.html
lisab
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Feb4-08, 06:02 PM
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Sounds like a whale passing gas.
Moonbear
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Feb5-08, 07:41 PM
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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.
RonL
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Feb5-08, 10:54 PM
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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?
LtStorm
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Mar3-08, 07:45 AM
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Quote Quote by Moonbear View Post
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.

Quote Quote by RonL View Post
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?
matthyaouw
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Mar3-08, 08:23 AM
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Quote Quote by RonL View Post
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.
glondor
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Apr10-08, 07:20 PM
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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.
DaveC426913
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Apr10-08, 09:22 PM
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Quote Quote by RonL View Post
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/
tuatha1337
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#14
Jan17-09, 01:42 AM
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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/acous...s_mystery.html
per.sundqvist
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#15
Feb10-09, 06:46 AM
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Could it be a sea version of the Sarlacc in StarWars?


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?
Ivan Seeking
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Feb10-09, 03:34 PM
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Quote Quote by per.sundqvist View Post
Could it be a sea version of the Sarlacc in StarWars?


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.

Got me!
B. Elliott
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Jul29-09, 10:25 PM
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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.
Topfish90
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#18
Sep2-09, 03:59 AM
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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 explaination. 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!


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