Great Ocean Secrets

It has been nearly 150 years since the publication of 20,000 Leagues Under the Sea, and scientists are still searching for the truth about many of the creatures and features of the deep

Scientists are still searching for the truth about many creatures and features of the deep.

“IMMORTAL” JELLYFISH

Could this tiny jelly hold the secret to curing cancer? Smaller than a pinkie nail, this creature has the Benjamin Button–like ability to revert to its polyp state, the earliest stage of its life, when threatened with starvation or injury, earning the nickname immortal jellyfish for how it appears to outsmart death. Although the species, Turritopsis dohrnii, has been known about for a hundred years, researchers didn’t discover this capacity until the 1990s. They are now wondering whether the jellyfish’s ability to regress and regrow could help fight diseases such as cancer in humans.

GIANT OARFISH

These snakelike creatures are the longest bony fish on Earth—they can grow to up to 56 feet. But they live at depths of around 3,300 feet, so not much is known about them. Two dead giant oarfish were found on California’s shores in 2013, prompting scientists to study samples from their remains to see whether storms, starvation, or illness potentially caused their deaths.

THE PURPLE ORB

In 2016, researchers found a single purple blob about the size of a pool ball in an underwater canyon off California’s coast. Stumped as to what it could be, they nicknamed it Blobus purpilis. Research is ongoing, but one hypothesis is that it is distantly related to snails.

CHALLENGER DEEP

This spot in the ocean near Guam is the deepest point on Earth—nearly 7 miles down. (Mount Everest is only 5.5 miles tall.) Located in the Mariana Trench, Challenger Deep has been visited by just three people: two oceanographers in 1960 and filmmaker James Cameron in 2012. It’s completely dark and only a few degrees above freezing in the trench, and the pressure is intense: eight tons per square inch. But marine life has managed to thrive. In fact, some researchers believe that life on Earth may have originated there.

THE YONAGUNI MONUMENT

Are they human-made steps and ancient pyramids that sank in an earthquake, or natural rock formations created by currents? These underwater structures off the coast of Japan, often called Japan’s Atlantis, have baffled experts since a diver found them in 1986.

MILKY-SEA PHENOMENON

Since the 17th century, sailors have reported encountering swaths of sea with a strange “milky” cast as far as the eye could see. But scientists were unable to explain it—or confirm it was real. Then, in 1995, a satellite captured an image of a milky sea off the coast of Somalia. It is thought that the glow was from luminous bacteria that attract fish in order to be eaten and survive in their guts. How the bacteria gather in numbers large enough for their bioluminescence to be seen from space is unknown.

THE 11,500-FOOT WATERFALL

Earth’s largest waterfall is actually underwater, beneath the Denmark Strait, where cold water sinks below warmer water and flows over an estimated 11,500-foot drop. Researchers are still trying to figure out how such a thing works. It’s much more powerful than waterfalls on land, with a downward flow of more than 123 million cubic feet per second, which creates what scientists describe as “massive turbulence.”

Blue whales are the largest animals to ever live. Even a newborn can weigh roughly 30 tons.