Did you know that in 2011 a bizarre underwater “icicle of death” was filmed by a BBC crew? They did it using timelapse cameras, under the ice at Little Razorback Island, near Antarctica’s Ross Archipelago.

The icy phenomenon, called a brinicle, is caused by cold, sinking
brine, which is more dense than the rest of the sea water. When
salt-rich water leaks out of sea ice, it sinks into the sea and can occasionally create an eerie finger of ice. Brinicles are found in both the Arctic and the Antarctic.