An unexplained sound echoed from Earth’s deepest abyss, and scientists admit they cannot fully identify it. The faint, persistent hum was detected by sensors buried miles below the ocean’s surface, a place where silence should be absolute.
In October 2014, a research vessel from Oregon State University traveled to the Mariana Trench in the western Pacific Ocean to study the deepest part of the seafloor. The team deployed an underwater drone equipped with sensitive listening devices, which descended nearly seven miles into darkness. At that depth, water pressure reaches roughly eight tons per square inch, and sunlight has not penetra…