In a remarkable deep-sea encounter, researchers have captured stunning video footage of one of the ocean's most elusive giants: the phantom jellyfish.
A Ghostly Giant in the Depths
The sighting occurred at a depth of 830 feet (approximately 253 metres) off the coast of Argentina. A remotely operated vehicle (ROV) from the Schmidt Ocean Institute was descending to explore the wall of the Colorado-Rawson submarine canyon when its lights illuminated the drifting form of the enormous creature. The resulting film, published on January 7, 2026, shows the jellyfish's translucent, bell-shaped body gently pulsing as it moves through the inky darkness, surrounded by small fish.
Measuring an impressive 10 metres in length, the jellyfish is distinguished by its four extraordinarily long, ribbon-like 'mouth arms'. Scientists believe these arms, which trail above the main body, are used to ensnare prey, though this hunting behaviour has never been directly witnessed. The species, known scientifically as Stygiomedusa gigantea, is thought to be one of the largest invertebrate predators in the deep-sea ecosystem.
An Elusive Deep-Sea Phantom
First discovered in 1899, the giant phantom jellyfish has been documented by scientists only around 100 times in over a century. It was not even formally recognised as a distinct species until 60 years after its initial discovery due to these extraordinarily rare sightings. The creature inhabits a vast vertical range, from near the surface down to an astonishing 21,900 feet, but it is most commonly found in the mesopelagic or 'twilight' zone, where sunlight barely penetrates.
Giant phantom jellyfish appear to live in all the world's oceans except for the Arctic. They have been filmed off the Pacific coast of the United States, near Japan, and in the Gulf of Mexico. Observations in the Gulf suggest a fascinating potential behaviour: the jellyfish may hunt by clinging to underwater structures with its arms to trap food.
Why Underwater Robots Are Key to Discovery
Studying such delicate deep-sea life is incredibly challenging. Before the advent of ROVs, researchers relied on trawling nets, which often destroyed specimens. When brought to the surface, the jellyfish's fragile, silky body disintegrates into a 'gelatinous goo', making ROVs the only effective tool for observation.
The rarity of these encounters is underscored by data from the Monterey Bay Aquarium Research Institute (MBARI). Despite their ROVs having completed thousands of dives, they have recorded the giant phantom jellyfish only nine times.
This latest footage from the South Atlantic not only provides a mesmerising glimpse of a deep-sea phantom but also highlights the critical role of advanced technology in uncovering the secrets of our planet's final frontier.
