Lifted From a Russian Lake, a Big, if Fragile, Space Rock
By DAVID M. HERSZENHORN
MOSCOW — Russian officials on Wednesday retrieved the largest fragment so far of a meteor that exploded in February over the city of Chelyabinsk, but as divers and a mechanical winch lifted it from the bottom of a lake, the rock broke into three pieces, and then broke the scale — literally — when all together it weighed in at more than 1,250 pounds.
Although a hole in the ice of Lake Chebarkul, southwest of Chelyabinsk, had made clear where the meteorite fragment landed, it took seven months of searching and a detailed sonar analysis to pinpoint its location, at a depth of about 40 feet and covered by about 8 feet of silt.
It then took another month of planning and work to prepare to lift it, a process that culminated Wednesday in front of a crowd gathered on the shore, with the events broadcast live on television.
After divers assured that the rock was secured with ropes, the regional governor, Mikhail Yurevich, hit a button to start the winch that pulled it to land.
As it was recovered, the meteorite fragment — which Russian scientists have estimated is more than 4.5 billion years old, or about as old as the solar system — was caught in a tangle of colorful ropes and cords, almost like an old piece of furniture tied to the top of a station wagon.
“Come on, finish up,” an official shouted as a crowd of photographers and cameramen clustered around for a close look. “It will be available in the museum.”
Scientists said the meteor was far larger when it entered the Earth’s atmosphere, perhaps as heavy as 10,000 tons.
More than 1,200 people were injured, mostly by shattered glass, when the meteor burst into the Earth’s atmosphere with a blinding streak of light and a series of sonic booms, before exploding 20 to 30 miles above Chelyabinsk.
Countless chunks of the meteor fell along its path, but what seemed likely to be the main piece left a jagged hole about 20 feet wide in the ice of Lake Chebarkul.
Scientists said that the dark, glassy surface of the rock, known as a fusion crust, and indentations on its surface were the classic markings of a meteorite and seemed to confirm its origins. Officials said it would be analyzed and then placed in a regional museum.
Once in the Earth’s atmosphere, meteors can drop fragments all along their path, with the largest typically being closest to the point of impact.
The breakup of the meteorite fragment into three pieces does not diminish its value to researchers, but it does undercut potential bragging rights. The sum total of the fragments discovered in Chelyabinsk has not come close to matching the biggest meteorites scientists have found, which tend to be 10 tons or more.
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