Robot Searching for the Endurance Wreck Uncovers Bizarre Underwater Structures
The frigid depths of the Weddell Sea have long concealed many of Antarctica’s secrets. In 2019, an expedition embarked on a mission to rediscover the lost wreck of Ernest Shackleton’s ship, the Endurance, which vanished in 1915.
Although the team did not locate the vessel right away, their remotely operated robot, affectionately named “Lassie,” returned with surprising footage of enigmatic formations scattered across the seafloor—patterns that have intrigued scientists ever since.
Six years later, researchers have finally unveiled the truth behind these underwater anomalies. A paper published in Frontiers in Marine Science (R.B. Connelly et al., 2025) describes that the seabed in this secluded Antarctic zone features more than a thousand circular depressions.
“Each of these pits appears unusually clean, with sandy interiors free of plankton debris that covers the surrounding sediments,”
wrote the authors, noting that the result is a landscape of remarkable geometry, quite unlike the typical seafloor terrain observed elsewhere in the region.
The original imagery captured by “Lassie” depicted a wide range of formations—some solitary, others arranged in winding lines, and several gathered densely side by side. The stark contrast between the clean, pale pits and the darker, debris-strewn seafloor around them immediately fascinated marine biologists.
Author’s Summary
The discovery near the Endurance wreck revealed thousands of clean, circular seafloor pits in the Weddell Sea, reshaping scientific views on Antarctic underwater formations.