According to scientists the loudest thing in the universe is the perseus galaxy cluster sound.
However there was another loud thing that was considered the loudest thing or loudest sound on the universe which was the bloop.
The Bloop was the given name of a mysterious underwater sound recorded in the 90s. Years later, NOAA scientists discovered that this sound emanated from an iceberg cracking and breaking away from an Antarctic glacier.
Another really loud sound that was thought to be the loudest sound or loudest thing on the universe was made by the Krakatoa volcanic eruption that occurred in the year 1883 which was so loud that the sound ruptured eardrums of people 40 miles away.
When you're around loud sounds you should wear ear protection because loud sounds can damage your eardrums and hearing.
But some loud sounds can even penetrate through earplugs and other ear protection.