The Bloop Sound

Overview

Ultra-low-frequency underwater sound detected by NOAA (1997) that was louder than any known animal, but with a waveform consistent with that of a living creature.

Investigation

Initially speculated to be a massive unknown sea creature. Later analysis attributed it to icequakes from large icebergs rubbing against the seafloor.

Why it matters

A fascinating example of how unexplained phenomena can spark scientific curiosity and lead to new discoveries, even if the initial mystery is eventually solved.