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Presumed meteorite pulled from lake Meteorite pulled from Russian lake
(about 1 hour later)
Divers working at a Russian lake have recovered what may be a 570kg chunk of the space rock that exploded over Chelyabinsk earlier this year. Divers working at a Russian lake have recovered a 570kg chunk of the space rock that exploded over Chelyabinsk earlier this year.
The object is thought to have plunged into Lake Chebarkul in central Russia leaving a 6m-wide hole in the ice. The object plunged into Lake Chebarkul in central Russia on 15 February, leaving a 6m-wide hole in the ice.
If confirmed, it would be the largest fragment of the meteorite yet found. If confirmed, it will be the largest fragment of the meteorite yet found.
More than 1,000 people were injured when a 17m, 10,000-tonne space rock burned up over Russia on 15 February. More than 1,000 people were injured when a 17m, 10,000-tonne space rock burned up over Central Russia.
Live footage showed a team pull out a 1.5-metre-long (five-foot-long) rock from the lake after first wrapping it in a special covering and placing it on a metal sheet while it was still underwater.Live footage showed a team pull out a 1.5-metre-long (five-foot-long) rock from the lake after first wrapping it in a special covering and placing it on a metal sheet while it was still underwater.
The boulder was then pulled ashore and placed on top of a scale for weighing, an operation that quickly went wrong.The boulder was then pulled ashore and placed on top of a scale for weighing, an operation that quickly went wrong.
The rock broke up into at least three large pieces as it was lifted from the ground with the help of levers and ropes.The rock broke up into at least three large pieces as it was lifted from the ground with the help of levers and ropes.
Then the scale itself broke, the moment it hit the 570kg (1,255lb) mark.Then the scale itself broke, the moment it hit the 570kg (1,255lb) mark.
But scientists cautioned that it would take time before they could verify that the rock pulled from the lake had indeed come from space. Dr Caroline Smith, curator of meteorites at London's Natural History Museum, confirmed that the object was a meteorite. She told BBC News: "Fusion crust forms as the meteoroid is travelling through the atmosphere as a fireball.
"The outer surface gets so hot it melts the rock to form a dark, glassy surface crust which we term a fusion crust. Regmaglypts are the indentations, that look a bit like thumbprints, also seen on the surface of the meteorite."
The divers' mission had been hampered by a number of factors. The rock fragment lay at 13m depth, not 6m or 8m as was originally thought.The divers' mission had been hampered by a number of factors. The rock fragment lay at 13m depth, not 6m or 8m as was originally thought.
The Vesti 24 rolling news channel reported that divers had already recovered more than 12 pieces from Lake Chebarkul since the incident on 15 February.The Vesti 24 rolling news channel reported that divers had already recovered more than 12 pieces from Lake Chebarkul since the incident on 15 February.
The station cautioned that only four or five of them had turned out to be real meteorites. The station said that only four or five of them had turned out to be real meteorites.