The Bloop Mystery

The Bloop Spectrogram courtesy of the NOAA

The Bloop — its very name sounds mundane or, at most, something that isn’t proper to bring up in polite society. However, the Bloop is much more than just an odd word. It is a mysterious sound that has raised a bit of controversy. To some, it is a mystery that may point to an unknown creature beyond our imagining. To others, it is simply a sound that has not been connected to a source yet, but most likely has a source that is far less surprising. Either way, the Bloop is a mystery, one that intrigues many.

In the summer of 1997, the National Oceanic and Atmospheric Administration Vents Program was monitoring sounds in the South Pacific using a system known as the Equatorial Pacific Ocean autonomous hydrophone array. In layman’s terms, this system is a series of hydrophones placed at distances of roughly 3,000 miles apart that pick up sounds in the ocean. It was initially a U.S. Navy system used to track the movement of Soviet submarines. It became a toy for the NOAA after the Cold War ended.

That summer, at a distance of roughly 1,087 miles off the coast of Chile, a low frequency sound thundered up from the depths of the ocean. The sound was exceptionally loud, being caught on more than one of the array’s sensors. It, for the most part, lasted roughly one minute whenever it occurred, which it did numerous times over that summer. However, the sound eventually stopped occurring or has simply not been caught with underwater listening devices since. The sound was nicknamed “The Bloop.”

Some say that the Bloop’s profile matches that of a living creature. Upon close, albeit untrained, examination, the claim holds up. It certainly doesn’t look or sound like volcanic activity or human-produced sounds beneath the ocean. That is coming from someone who doesn’t know how to look for the more subtle differences in spectrograms and underwater audio. Nonetheless, the claim that it is biological in origin is hard to substantiate, given that the origins of the claim may have been a mere off-hand comment by an expert. The NOAA website, while containing recordings and descriptions of the Bloop, makes no claims to its origins.

The popular story behind the Bloop mystery goes further than the sound being made by an animal. It goes on to say that the sound is so loud that it simply could not have been made by any known sea creature. The largest animal ever known in history or prehistory is the blue whale. The blue whale is incapable of making such a noise. It would take something much larger or something with some very productive vocal organs that are heretofore unknown to science.

It should be mentioned that the NOAA has several recordings of unidentified sounds recorded in the ocean. The Bloop is the most sensational because it is so tremendous and because of the claims of biological origin, but it is certainly not alone when it comes to strange sounds of the sea. Like the others, it is likely that we will not discover what made the Bloop unless it is heard again and traced to its source. This is not likely considering what it would take to not only monitor the hydrophone array, but to have field workers ready to go out and investigate the sounds. For now, we just have to admit that we do not know.

The Bloop Audio (Note: The Audio has been altered by the NOAA. It has been sped up to 16 times its speed. Therefore, the sound is brief, but in reality, it lasted much longer.)

Sources
Bellows, Alan, Call of The Bloop, retrieved 10/8/11, damninteresting.com/the-call-of-the-bloop
Vents Program Acoustic Monitoring, retrieved 10/8/11, pmel.noaa.gov/vents/acoustics/sounds/bloop.html