Nearly 30 years after it was first heard, the mysterious underwater noise called the Bloop is finally understood. Detected in 1997 by NOAA’s Pacific hydrophones, the Bloop travelled over 3,200 km across the Pacific Ocean. At first, many thought it came from a living giant creature like the ancient megalodon shark, which could grow over 24 metres long. The loud, rising sound puzzled scientists and sparked wild theories, including huge unknown sea monsters and even H.P. Lovecraft’s fictional Cthulhu. But after years of study, NOAA found the real cause in 2005. The Bloop was the noise of an icequake—an iceberg cracking and breaking off from an Antarctic glacier. This explanation fits better with science and our knowledge of sharks. Megalodon went extinct about 3.6 million years ago and left no recent teeth or evidence. Also, an enormous shark would need large prey and would be noticed by today’s tracking and fishing industries. Some fans were disappointed by the truth, hoping for a new giant sea creature discovery. Others questioned why it took so long to find the source. The ocean is huge, and it takes time to collect enough data to identify strange sounds. Today, the Bloop stands as a reminder that our planet is changing. The creaking ice signals rising temperatures and melting glaciers, not lurking monsters. The deep ocean still holds secrets, but often the scariest sounds come from Earth itself moving under pressure.