The term “bloop” is often associated with a mysterious underwater sound detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) in 1997. It was a powerful, ultra-low frequency sound detected by underwater microphones placed thousands of miles apart. The sound stood out because of its volume and its source’s unknown nature.
The size or physical dimensions of the “bloop” itself aren’t quantifiable in the conventional sense, as the term refers to the sound’s characteristics rather than a physical object. However, the sound’s volume and reach were significant. It was picked up by sensors over 5,000 kilometers (about 3,100 miles) apart, indicating that it was extremely loud and originating from a source capable of producing such a powerful noise.
Initially, there was much speculation about the source of the “bloop,” ranging from giant sea creatures to underwater geological events. However, it’s generally accepted now that the sound was consistent with noises generated by icequakes—large icebergs cracking and fracturing in Antarctica’s ice.
This conclusion is based on comparisons of the “bloop” sound with the noises produced by ice breaking off from glaciers and cracking in the ocean. The sound was likely a natural event and not related to any large marine animal, as some early speculations suggested.