While science has allowed us to explore most of the planet, remarkably, our oceans remain vastly unexplored. Thankfully, new discoveries through modern technology continue to help advance our knowledge of the blue planet every day.

But sometimes, even the world’s top scientific experts can get completely stumped by deep-sea oddities. These 20 strange discoveries prove that not all aquatic legends are mere sailors’ tales, and may even hold the key to unlocking the secrets that lie beneath us.

1. Massive peeper: This huge eye was found floating in the ocean near Fort Lauderdale, Florida. Scientists believe it was from a large swordfish, but that doesn’t quite measure up…

CARLI SEGELSON / FLA. FWCC

2. Alien spacecraft: An object straight out of Star Wars was discovered by Swedish explorer Peter Lindberg’s crew at the bottom of the Baltic Sea. Dating techniques suggest it’s 140,000 years old! Many believe it to be remnants of a UFO crash.

3. Glowing water: For centuries sailors have told stories of stumbling upon milky, florescent seas. Scientists believe that it’s caused by a special type of bacteria that continuously illuminates the water. Why? That’s still a bit of a mystery.

Doug Perrine / BBC

4. Sunken city: Strange structures were discovered off the coast of Japan in 1986 and nicknamed “Japan’s Atlantis.”Are they natural rock formations or a hidden city? You can take a look for yourself as it’s a popular diving spot. 

5. Strange sounds: A distinct, unidentifiable sound was recorded by scientists in 1991. Since its first recording, ‘the sound’ has been detected in areas all across the Pacific Ocean. Scientists believe it is the sound of lava coming into contact with ocean water, but they just aren’t sure. 

 6. An ancient city: In 2002, marine scientists discovered archaeological structures from an ancient Indian city that dates to around 9,000 years old. That makes it one of the oldest civilizations of all time… if it’s real! 

7. UFO base: An odd, staircase-looking structure in Antarctica was recently spotted on Google Earth. Some scientists believe it is just an impact crater, but others theorize the possibility of UFOs and old Nazi bases.

SPL / BBC

8. Missing land: The island of Bermeja was located in the Gulf of Mexico for years… that is until no one could find it anymore. Mexican officials conducted an investigation, but found nothing. Conspiracy theorists believe the CIA had something to do with its disappearance.

9. Ooze: In 2016, the Ocean Exploration Trust discovered a strange purple blob on the ocean off the coast of California. They joked about it being many things like a giant spider sack or small mother octopus, ultimately nicknaming it Blobus purpilis. Its true identity is still unknown.

OET/NautilusLive

10. Missing subs: Four submarines vanished without a trace in the Atlantic years ago. The disappearances of the USS Scorpion, INS Dakar, French Submarine Minerve, and Soviet K-129 were never solved. Theorists speculate scenarios ranging from secret Soviet attacks to faulty designs.

11. Macho whale calls: Blue whales mating calls have been recorded for about 40 years. Recently, however, marine biologists discovered strikingly deeper frequencies. Some think the change is due to an increase in mating competition…

12. Atlantis: When explorers discovered ruins on the barren seafloor of Cabo de San Antonio, Cuban people speculated that the lost city of Atlantis had been found. After a media frenzy, 10 years went by with no answers. Was this a government cover-up? 

13. Trains: Captain Paul Hepler and his crew boarded the Venture III in 1985 to scan the ocean floor along the New Jersey coastline. They discovered long, rectangular objects later determined to be old train cars. How they ended up swimming with the fishes is unknown.

14. Eerie noises: In 1999, a 15-second long recording of an unrecognizable oceanic sound was made. It is unknown exactly what this was a recording of but since then, scientists believe it was the sound of an iceberg running aground. But it could it have been something more sinister? 

David Bezaire / flickr

15. Bimini Road: Submerged under 20 feet of crystal clear Bahamian water, is what looks like an abandoned road. Geologists and archaeologists are in disagreement whether this is part of a lost city or just natural limestone erosion.

16. Cthulhu: A strong, ultra-low frequency “bloop” was recorded in 1997 at several stations, thousands of miles apart. Scientists haven’t ruled out the possible origins being from an unknown massive creature like the legendary Cthulhu. The sound has never been heard or recorded since.

Walt Disney Pictures

17.  Strange stones: A cone-shaped, basalt rock structure was discovered by scientists in the Sea of Galilee in 2003. Twice the size of Stonehenge, archaeologists noted its resemblance to a burial ground, but have never discovered something like this.
 

18. A mummy: The body of a German sailor, Manfred Fritz Bajorat, was found in his sunken yacht off the coast of the Philippines. Autopsy results revealed the accident happened just seven days prior. So, how did he become completely mummified in such a short time span?

19. Floating circles: These strange, circular objects have been seen in oceans all over the planet. If they are burial structures, like scientists believe, then those submerged beneath have been better preserved than those in the dry desert!

20. Real-life sea monsters: Recently, a 9 foot-long great white shark’s tag washed up onto the shore, bloody and battered. Scientists concluded that the shark was eaten by an unknown, larger sea creature…

Ridzi25 / flickr.com

This just goes to show that the ocean can be a strange and chilling place. Sometimes things are better left undiscovered.

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