Researchers at Oregon State University have may have discovered the source of the mysterious sound in the Mariana Trench. Findings reveal that the sound may be from a Minke whale.

OPB reported that the researchers believe the mysterious sound coming from the Mariana Trench may be the song of a Minke whale. The song is named as the "Western Pacific Biotwang."

It starts with a low moan, which is common for baleen whales. However, towards the end, it has a metallic sound that intrigued the researchers.

"What makes this call special is the second part, and the way it sweeps way up and it sort of has that metallic twang sound to it," OSU researcher Sharon Nieukirk said. "Not many animals make a call with this frequency sweep - that goes from such a low frequency to a very high frequency."

The same high-pitched sound has been heard from Minke whales found near the Great Barrier Reef in Australia. Nieukirk added that the song may not have been identified yet due to how scientists analyze acoustic data from the ocean.

Apparently, scientists check the low-, middle- and high-pitched sounds separately. The OSU researcher noted that, with this particular song, scientists need to look at all parts simultaneously. "It is possible that others have recorded it in the past, and just didn't put the pieces of this puzzle together," she said.

According to Science Alert, the call spans frequencies as low as 38 hertz and as high as 8,000 hertz. It was reported that the sounds do not seem to have any human or geological origin. This led to the hypothesis that the complex sounds were produced by "a biological source."

It was also noted that the song was recorded throughout the year. This means that it may not be a mating call, which is usually made by baleen whales during the winter.