25 Deep Sea Mysteries And Oddities That Will Leave You Baffled

More humans have walked on the moon than have been to the deepest parts of planet Earth. Covering 70% of Earth’s surface, the oceans are the largest habitat in the world yet we only know around 1% of the seafloor. Many a mystery surrounds the deep blue and in this list we dredge up some of the least understood. Check out these 25 deep sea mysteries and oddities that will leave you baffled!

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Giant Oarfish

Giant oarfish

Thought to be the reason for many alleged sea serpent sightings, the giant oarfish can reach up to 36 feet (11m) long – that’s bigger than a shipping container. Previously assumed to be quite rare, these mostly unknown creatures seem to be more common than once thought.


Deepwater Photosynthesis

Marine bacteria

There may be no sunlight at the bottom of the ocean, but some bacteria near hydrothermal vents use the vents’ dim red glow to photosynthesize and produce food for themselves. Scientists are still trying to figure out how it’s all possible.



NOAA Upsweep electrograms

The NOAA listens to sounds from oceans all over the world. Most have been identified, but the sound known as upsweep remains elusive to understand. Upsweep is a few seconds of narrow-band upsweeping sounds and is most active in Spring and Autumn.


Vampire Squid

Vampire squid

The vampire squid is a bizarre creature which produces some of its own light through glowing tentacle tips and spots on its sides. If disturbed, it can eject an ink which glows.


The Baltic Anomaly

Baltic Sea Anomalybeforeitsnews.com

The Baltic Anomaly is a still-unknown item in the Baltic Sea which some say could be a pre-Ice Age artifact or Nazi anti-submarine device. Oddly, divers’ electrical equipment stops functioning within 650 feet (200m) and a strong radio signal comes off from just near the item.

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