PARIS (AFP) - 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 (ESA) said on Monday.
As expected, an estimated 25 per cent of the one-tonne GOCE satellite reached the Earth's surface, said an ESA statement, but "no damage to property has been reported". It did not say where the fragments hit.
GOCE "is only a small fraction of the 100-150 tonnes of man-made space objects that re-enter Earth's atmosphere annually," said Mr Heiner Klinkrad, head of ESA's space debris office. "In the 56 years of spaceflight, some 15,000 tonnes 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, totalling some 200kg - about the weight of car engine - would survive contact with the atmosphere.
The Gravity Ocean Circulation Explorer (GOCE) satellite was placed in orbit in 2009 on a mission to monitor variations in gravity and sea levels. 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.
GOCE was launched in March 2009 at an altitude of 260km - later lowered to 224 km - the lowest ever for a research satellite.
The 350-million-euro (S$583 million) mission lasted twice as long as its initially-scheduled 20 months.
ESA said the satellite re-entered the atmosphere around midnight GMT Sunday on a descending orbit that crossed Siberia, the western Pacific Ocean, the eastern Indian Ocean and Antarctica.
GOCE was designed and built before 2008, when international recommendations were adopted that a scientific satellite must be able to execute a controlled re-entry, or burn up completely after its mission.