From the NY Times
Lifted From a Russian Lake, a Big, if Fragile, Space Rock
Anton Melnikov/Reuters
By DAVID M. HERSZENHORN
Published: October 16, 2013
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.
Multimedia
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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