* Astronomy

This sound was repeatedly recorded during summer, 1997 on the Equatorial Pacific Ocean autonomous hydrophone array. The sound 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.  It yields a general location near 50°S; 100°W.

Although the Bloop is one of the loudest sounds of any type ever recorded in Earth's oceans, their origin remains unknown.

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