We still don’t know

An immortal jellyfish? 10 spooky and unanswered questions about the sea

Some people are scared of the ocean. Can you blame them? Though waters cover 70% of our planet, scientists are still scratching their heads about certain unanswered questions. How long can blue whales actually live? What substance makes some waters glow eerily white at night? And what’s with the self-rejuvenating, immortal jellyfish? These are some of the mysteries we’ll explore in this article!

Found abandoned in 1872 with sails set, cargo intact, and dinner still on the table, the Mary Celeste is the poster child for maritime enigmas. The whole crew vanished without a trace and was never heard of again.

Mutiny? Rogue wave? Alcohol fumes? Giant squid? No theory fully fits. It's a fascinating tale that has been the subject of documentaries, theatre plays, novels, and movies.

For centuries, sailors have reported seeing entire portions of the ocean surface glowing white at night, like a ghostly reflection.

An explanation could be massive blooms of bioluminescent bacteria, but no one knows how they coordinate light across such huge distances or why the phenomenon lasts for hours. Even with satellite detections, it remains one of the ocean’s eeriest light shows.

Tales of a giant squid have been alive for centuries, but it was only in 2004 that humanity was able to photograph this fabled creature. In that year, a Japanese team captured a live one on camera in its natural habitat and finally proved that the creature behind centuries of sea-monster legends was very real.

And yet, we still know shockingly little about its life cycle, breeding habits, or how something that big stays so well hidden.

You’d think the largest creature ever to exist would be the easiest to study. Nope. We still struggle to track migration patterns, understand their communication system, or explain the full recovery timeline after they were nearly hunted to extinction.

Turritopsis dohrnii cheats death by reverting its adult cells back to a juvenile state when stressed. It’s like if a human under pressure suddenly turned back into a toddler.

This regeneration process is wildly complex and not fully understood, and scientists hope that cracking its secret might reveal insights into aging itself.

The stretch between Florida, Bermuda, and Puerto Rico has inspired endless theories. Unexplained disappearances, bizarre compass behavior, and strange weather patterns have contributed to building the legend.

Scientific explanations abound, from methane hydrates to violent storms, but the Triangle’s mythic aura refuses to die.

The Challenger Deep, the trench’s lowest point, plunges almost 7 miles. Only a handful of people have ever explored its bottom, including filmmaker James Cameron in 2012.

What lives down there? What geological processes unfold under such pressure? Every new expedition reveals creatures that look like they belong in fever dreams.

Off the coast of Japan lies a submerged stone structure with terraces, pillars, and sharp geometries that seem carved… Unless they were shaped by strange phenomena of nature.

Some believe it’s the remains of an ancient city, sunken after an earthquake; others argue it’s purely geological. Today, it’s a riddle lying quietly under turquoise waters.

In 1918, a massive US Navy collier vanished without a distress call while crossing the Caribbean. More than 300 people disappeared with it, the single largest non-combat loss of life in U.S. Navy history.

No wreckage has ever been found. Storm? Structural failure? Something stranger? The sea has kept its mouth shut.

This line gets repeated a lot because it’s shockingly true. With sonar mapping still incomplete and most of the ocean floor left untouched by human eyes, researchers say we’ve charted only about a quarter of it in detail.

Mars, by contrast, has been mapped in full thanks to satellites. The ultimate plot twist is that we might understand another planet better than our own.

10 weird historical events that no one has been able to explain (yet)

Image: Walters Art Museum, Public domain, via Wikimedia Commons

Who doesn't like a good mystery? And if the mystery isn’t a work of fiction but the result of a true story, even better! The great unsolved enigmas of history are absolutely fascinating. Some have been solved over time, but there are still many old secrets for which neither scientists nor historians have found an explanation—yet. Time-travel with us as we uncover 10 of the biggest historical mysteries that will probably never be cracked!

Image: Tanner, Henry S., Public domain, via Wikimedia Commons

Bermeja Island is mentioned in navigation texts written by European travelers and appears in cartography from the 16th to 19th centuries. Old maps place it off the north coast of the Yucatán Peninsula; however, multiple searches over the years have yielded no concrete evidence of its existence.

So, what happened to Isla Bermeja? Was it a cartographic error? Did it sink due to a tidal wave? Because of its geopolitical significance, some have even suggested that it was blown up by the CIA! A 2009 study by the Autonomous University of Mexico concluded that Isla Bermeja does not exist today, nor were any traces found at its supposed coordinates. Yet, it will forever remain a mystery that will surely keep many entertained.

Image: Credit: Big Ear Radio Observatory and North American AstroPhysical Observatory (NAAPO)., Public domain, via Wikimedia Commons

In 1977, Ohio State University’s Big Ear radio telescope, used in the search for extraterrestrial intelligence, detected a signal now known as the Wow! signal. While reviewing the data, astronomer Jerry R. Ehman noticed a sequence represented as "6EQUJ5." Baffled by the anomaly, he circled it and wrote "Wow!" in the margins.

The signal lasted 72 seconds and, unfortunately, has never been repeated. To this day, no one can fully explain the phenomenon, although some suggest it may have come from a man-made source. Still, the Wow! signal remains one of the strongest candidates for potential extraterrestrial contact ever detected.

Image: Edward S. Curtis, Public domain, via Wikimedia Commons

How is it possible for an entire village to vanish without a trace? Believe it or not, this is said to have happened nearly a century ago. According to lore, a small Inuit village in Canada was well known among fur trappers who visited regularly to trade. But in 1930, something very strange supposedly occurred.

A hunter named Joe Labelle claimed he visited the village one day and couldn’t find a single person. Reports said there were guns and food left behind, and even claims that the graves in the cemetery were empty. A thorough investigation, however, found no conclusive evidence of what happened to the villagers. Some witnesses from nearby towns even reported seeing a huge green light. Theories ranged from mass migration to extraterrestrial abductions. The Royal Canadian Mounted Police has since dismissed the case as an urban legend. Some still believe the story to be true.

Image: bbb

We know thousands of shipwreck stories, but this one is quite unique. The MV Joyita, designed to be nearly unsinkable, was found adrift in the South Pacific, practically unharmed, but the crew had disappeared completely.

In October 1955, the American merchant vessel left the port of Apia in Samoa with 16 crew members and 9 passengers bound for the Tokelau Islands. After days without news, a rescue mission was launched. Five weeks later, the Joyita was spotted more than 600 miles west of its intended route. The vessel was partially submerged, and there was no sign of the passengers or crew. Four tons of cargo and all three life rafts were missing. They were never seen again.

Image: Gary Todd from Xinzheng, China, CC0, via Wikimedia Commons

Do you know where one of the best-preserved mummies was found? Hint: not in Egypt. Xin Zhui, the Marquise of Dai during the Western Han Dynasty in China, was discovered in her tomb at Mawangdui 2,000 years after her death, along with hundreds of valuable documents and artifacts.

What makes this mummy so extraordinary is how well-preserved her body is. Her organs and veins remain intact, and she still has hair and even eyelashes. Scientists analyzed the fluid present in the coffin and discovered it was acidic and contained salt and magnesium. They believe this mysterious liquid may have been responsible for preserving Xin Zhui so well. What they don’t know is whether it was intentionally poured into the coffin or came from the body itself.

Image: Yoichi Okamoto, Public domain, via Wikimedia Commons

The United States has its fair share of presidents who died while in office, but none of our 45 presidents have ever disappeared without a trace. Did you know that this actually happened in The Land Down Under?

Harold Edward Holt was the Prime Minister of Australia from 1966 until his presumed death in 1967. He loved the ocean and spearfishing. During a weekend trip with friends, Holt visited the remote Cheviot Beach to take a swim. Rough sea conditions that day caused him to be swept away by the waves, and he never reappeared. Despite an intensive search, his body was never found, which has given rise to numerous conspiracy theories. Ironically, Australians built the Harold Holt Memorial Swimming Centre in Melbourne in his honor.

Image: FBI, Public domain, via Wikimedia Commons

Many famous criminals have managed to remain unidentified for decades, but the D.B. Cooper case is something else entirely. In 1971, Cooper boarded a flight from Portland to Seattle. Shortly after takeoff, he showed a flight attendant a device he claimed was a bomb and demanded four parachutes and $200,000 in cash.

The crew landed to meet Cooper’s demands in exchange for the passengers and then took off again. As the plane flew over southwestern Washington, Cooper jumped into the cold, rainy night carrying his haul. His whereabouts and true identity were never discovered, although it is likely he didn’t survive the jump. In 1980, some of the ransom money was found near the Columbia River. Although the FBI officially closed the case in 2016, amateur sleuths continue to try to crack it.

Image: Pieter Brueghel the Elder, Public domain, via Wikimedia Commons

Can you imagine an epidemic where the main symptom is uncontrollable dancing? Sounds like science fiction, doesn’t it? Yet this really happened during the Middle Ages. In 1518, a dancing plague struck Strasbourg, Alsace, in what is now France. This strange condition affected up to 400 people, making them dance frantically for weeks. It is said that some even died of heart attacks, exhaustion, or strokes.

Doctors and authorities tried all kinds of measures to stop the spread. They even banned music for a while! To this day, scientists are not certain what caused this bizarre condition: it may have been food poisoning from toxins in the ergot fungus, or perhaps a case of stress-induced mass hysteria.

Image: Public domain, via Wikimedia Commons

The Voynich manuscript is a codex written roughly 500 years ago in an unknown language and writing system by an anonymous author. Known as Voynichese, the manuscript was named after Wilfrid Voynich, a Polish bibliophile and antiquarian who purchased it in 1912.

Radiocarbon testing has shown that it dates to the early 15th century. Many cryptographers and codebreakers have attempted to decipher its roughly 240 pages without success. The manuscript contains diagrams and illustrations of unknown plants and astrological symbols. Some believe it may be a made-up language, a secret code, a work of fiction, or even a hoax. If you think you can solve this mystery, the Voynich manuscript is available for viewing at Yale University’s Beinecke Rare Book and Manuscript Library.

Image: Bernhard

Similar to the Voynich manuscript, the Phaistos Disc is a fired clay disc believed to have been created during the Bronze Age. It was discovered by an Italian archaeologist in the basement of a palace in Crete, Greece, in 1908.

What makes this disc fascinating is that it contains a mysterious message. Stamped into the clay is a set of signs, forming a text that many scientists have tried to decipher—without success. It is considered an early attempt at printing, a technological innovation that would not become widespread for several centuries. While enthusiasts still hope the enigma can be solved, this is unlikely unless other documents are discovered to provide context.