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Meteorite pulled from Russian lake | Meteorite pulled from Russian lake |
(35 minutes later) | |
Divers working at a Russian lake have recovered a half-tonne chunk of the space rock that exploded over Chelyabinsk earlier this year. | Divers working at a Russian lake have recovered a half-tonne chunk of the space rock that exploded over Chelyabinsk earlier this year. |
The object plunged into Lake Chebarkul in central Russia on 15 February, 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. |
Scientists say that it is the largest fragment of the meteorite yet found. | Scientists say that it is 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 Central Russia, breaking windows and rocking buildings. | More than 1,000 people were injured when a 17m, 10,000-tonne space rock burned up over Central Russia, breaking windows and rocking buildings. |
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 fragment was then pulled ashore and placed on top of a scale for weighing, an operation that quickly went wrong. | The fragment 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. |
Dr Caroline Smith, curator of meteorites at London's Natural History Museum, confirmed that the object was a meteorite from characteristic features known as fusion crust and regmaglypts, which are obvious in images. | Dr Caroline Smith, curator of meteorites at London's Natural History Museum, confirmed that the object was a meteorite from characteristic features known as fusion crust and regmaglypts, which are obvious in images. |
She told BBC News: "Fusion crust forms as the meteoroid is travelling through the atmosphere as a fireball. | 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 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." |
Sergey Zamozdra, an associate professor at Chelyabinsk State University, told the Interfax news agency: "The preliminary examination... shows that this is really a fraction of the Chelyabinsk meteorite. | |
"This chunk is most probably one of the top 10 biggest meteorite fragments ever found." | "This chunk is most probably one of the top 10 biggest meteorite fragments ever found." |
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 said 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. |