The Bloop (1997)

The Bloop remains one of the ocean's most intriguing mysteries. In 1997, NOAA's hydrophones detected this ultra-low-frequency sound in the remote Pacific, lasting about a minute and powerful enough to be heard 5,000 km away. Initially theorized to come from an enormous, undiscovered sea creature due to its organic waveform, scientists later attributed it to icequakes from massive icebergs fracturing. However, its exact origin continues to spark debate among researchers. The Bloop's eerie, otherworldly quality and sheer volume (far exceeding any known animal) have cemented its place in marine lore, representing both the known limits of ocean science and the enduring mysteries of the deep.