The Icicle of Death
Under the Antarctic ice, a finger of ice grows slowly down to the sea floor, then spreads across it, freezing starfish and sea urchins where they lie.
What was reported
In 2011, a BBC film crew working on the series Frozen Planet filmed something few people had seen: under the sea ice near Little Razorback Island in Antarctica, a tube of ice grew downward from the frozen surface like a slow, creeping finger. When it reached the sea floor, it spread out as a web of ice, trapping and freezing the slow-moving starfish and sea urchins in its path.
The time-lapse footage, nicknamed the 'icicle of death', was shown around the world.
Explanations offered
It's called a brinicle. When sea water freezes, salt is pushed out as very cold, very salty brine. This brine is heavier than the sea water around it and sinks, freezing the water it touches into a hollow tube of ice. Some scientists think similar processes in the deep sea could have helped the first life on Earth form.
- When
- Filmed in 2011
- Where
- Little Razorback Island, McMurdo Sound, Antarctica
- Witnesses
- A BBC film crew
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.
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