Museum expert confirms the large fragment of rock lifted from the bottom of Lake Cherbarkul this week is definitely a meteorite.
The largest chunk yet of the meteorite that streaked across the sky above Chelyabinsk, Russia was pulled up from the bottom of a lake yesterday.
Museum meteorite expert Dr Caroline Smith said the fragment, weighing around 570 kilograms, shows clear features indicative of a meteor that has travelled through the Earth’s atmosphere.
‘The outer surface gets so hot it melts the rock to form a dark, glassy surface crust, which we term a fusion crust,’ she said.
The fragment also has regmaglypts on its surface, indentations that form when swirls of hot gas scour the outside of the meteor during its fireball stage.
Smith said the meteorite’s chemical composition indicates that it hails from the asteroid belt, a region littered with meteoroids lying between Mars and Jupiter.
The Chelyabinsk meteorite exploded during its descent through the sky in February and fractured into many pieces. Local residents noticed a hole in the ice of the frozen Lake Chebarkul, but experts were sceptical that a piece of the meteorite had caused it.
Initial exploration of the lake floor turned up nothing, but a subsequent dive probed the thick layer of silt at the bottom of the lake and discovered the fragment that was hauled up yesterday.
‘It’s one of the largest fragments of stony meteorite that’s ever landed on Earth,’ said Smith. The fragment will probably be dried before small fragments are cut off for research.