中國網(wǎng)站品牌欄目（頻道）
A spent science satellite that had measured Earth's gravity field re-entered the atmosphere on Sunday night and mostly disintegrated as planned, the European Space Agency said on Monday.
As expected, an estimated 25 percent of the 1-ton GOCE satellite reached Earth's surface, said the ESA in a statement, but "no damage to property has been reported."
There was no immediate word on where and when any debris may have landed.
GOCE "is only a small fraction of the 100-150 tons of man-made space objects that re-enter Earth's atmosphere annually", said Heiner Klinkrad, head of ESA's space debris office.
"In the 56 years of spaceflight, some 15,000 tons of man-made space objects have re-entered the atmosphere without causing a single human injury to date."
Scientists had predicted that several dozen fragments of GOCE, totaling some 200 kilograms -about the weight of a car engine - would survive contact with the atmosphere.
The GOCE, or Gravity field and steady-state Ocean Circulation Explorer, was launched in 2009 to map the Earth's gravitational field.
ESA said its information is being used to understand ocean circulation, sea level, ice dynamics and the Earth's interior.
The sleek, finned craft's mission came to a natural end when it ran out of fuel on Oct 21, leaving it without power to maintain its altitude in low orbit, where there are still lingering molecules of air.
The 350 million euro ($469 million) mission lasted twice as long as its initially scheduled 20 months.
ESA said the satellite re-entered the atmosphere around midnight on Sunday on a descending orbit that crossed Siberia, the western Pacific Ocean, the eastern Indian Ocean and Antarctica.
（中國日報網(wǎng)英語點津 Helen 編輯）
About the broadcaster:
Anne Ruisi is an editor at China Daily online with more than 30 years of experience as a newspaper editor and reporter. She has worked at newspapers in the U.S., including The Birmingham News in Alabama and City Newspaper of Rochester, N.Y.
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