The “Upsweep” is a seasonal sound recorded by autonomous hydrophones in the Pacific Ocean. In 1991, it was First discovered by the Pacific Marine Environmental Laboratory, the source of this underwater sound remains a mystery and still is a challenge for scientists.
There are many sounds recorded in the world till now that have not got it clear what it is actually, the sounds from mountains, sounds from deep oceans, and even the sounds from outer space. The alternative theory can be brought in easily but finding the exact origin is difficult.
Even science cannot explain many things, this Upsweep sound is also one among them. From 1991, “a long train of narrow-band upswept sounds lasting several seconds” has been recorded in the Pacific Ocean. The sound level peaks in the fall and spring and is strong enough to be detected throughout the Pacific.
The source may be located at approximately 54o S, 140oW, near the location of the inferred volcanic seismicity, but the origin of the sound is not resolved. The sound has decline from the origin since 1991 but still detect on NOAA’s equatorial autonomous hydrophone arrays.
Sometimes it feels like an empty space sound, a sound from hell or some horror kind. We don’t know if any alien activity is going on everything is still mysterious and unknown.
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