On a January morning in 2025, an iceberg the size of Chicago broke free from the George VI Ice Shelf in Antarctica. It drifted into the frigid waters of the Bellingshausen Sea, leaving behind a yawning patch of ocean that hadn’t seen daylight in centuries.

Twelve days later, a research vessel named Falkor (too) arrived at the scene.

What the scientists aboard discovered beneath the ship stunned them.

Hidden Life Beneath the Ice

“We didn’t expect to find such a beautiful, thriving ecosystem,” said Dr. Patricia Esquete, a marine biologist from the University of Aveiro in Portugal and one of the expedition’s co-chief scientists. “Based on the size of the animals, the communities we observed have been there for decades, maybe even hundreds of years.”

Hidden beneath nearly 153 meters (500 feet) of ice, the newly exposed seafloor revealed corals as thick as a person’s arm and sponges the size of beach balls. Surrounding them, icefish hovered near the bottom, huge sea spiders crept along the sediment, and octopuses shuffled quietly through the water.

The scientists had pivoted from their previous mission when they learned about the calving of iceberg A-84 on January 13. By January 25, their remotely operated vehicle, ROV SuBastian, was diving to depths of more than 1,000 meters, making the first human observations of this long-hidden stretch of Antarctic seafloor.

The eight days of exploring might reshape our understanding of how life endures in the most inhospitable corners of the planet.

Life Finds a Way

It’s hard to overstate how little we know about the ecosystems beneath Antarctica’s floating ice shelves. In 2021, British researchers made headlines by drilling through the Filchner-Ronne Ice Shelf and finding hints of life clinging to a boulder. But the view was limited to whatever the drill hole happened to land on.

This expedition was different.

Using SuBastian, the researchers could roam the dark seafloor and capture high-definition footage of vast benthic landscapes. They saw massive coral structures supporting whole communities of life—defying the assumption that such places are barren. In fact, the biodiversity was so rich that scientists believe they may have found species never seen before.

But one question loomed over the entire expedition: how does this ecosystem survive?

Typically, deep-sea life depends on marine snow—a slow trickle of dead plankton and organic debris sinking from the surface. But for centuries, this region was sealed beneath 150 meters of solid ice. Sunlight couldn’t penetrate. Photosynthesis couldn’t occur. That snow should never have fallen. Yet there it was: as vibrant as ever.

The team suspects ocean currents might be delivering nutrients from open water, perhaps funneled through underwater gullies that cut into the continental shelf. But the truth is no one yet knows for sure.

How’s That for an Icebreaker?

As the researchers explored this lost world, they were also collecting vital clues about the past—and future—of the Antarctic ice sheet.

The collapse of ice shelves like George VI has accelerated in recent years, a consequence of warming oceans and shifting climate patterns. When icebergs calve, they don’t directly raise sea levels, but they release pressure from glaciers behind them, which then flow faster into the ocean, contributing to sea level rise in a worrisome feedback loop.

“The ice loss from the Antarctic Ice Sheet is a major contributor to sea level rise worldwide,” said Dr. Sasha Montelli of University College London, the expedition’s other co-chief scientist. “Our work is critical for providing longer-term context of these recent changes, improving our ability to make projections of future change—projections that can inform actionable policies.”

To build that context, the team deployed underwater gliders to measure how meltwater from the George VI Ice Shelf is affecting the chemistry and temperature of the surrounding sea. Early data suggest strong biological productivity and an active freshwater outflow—potentially a nutrient source for the newly uncovered ecosystem.

The expedition is part of the Challenger 150 program, a global initiative endorsed by UNESCO’s Intergovernmental Oceanographic Commission to study deep-sea biodiversity during the UN Decade of Ocean Science.