This sound was recorded on March 1, 1999 on the Equatorial Pacific Ocean autonomous hydrophone array. The source of the sound is unknown, but is sufficiently loud to be heard over the entire array. The duration is approximately 15 seconds and is severely band limited. The approximate origin is 1999JD60 2218Z near 15S, 98W.  

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162K wav file(The recorded signal has been sped up 16 times)