U.S. offers some satellite strike data to China

Hazard not completely ruled out
Unlike most spacecraft that fall out of orbit and re-enter the atmosphere, this satellite had an almost full fuel tank because it lost power and became uncontrollable shortly after it reached its initial orbit in December 2006. Cartwright said the hydrazine alone was justification for undertaking the unprecedented effort to use a Navy missile interceptor to attempt to destroy the satellite in orbit.

Cartwright said experts were still watching the debris fields and he could not yet rule out that hazardous material would fall to Earth. But he said that as of Thursday morning, debris had only been seen in the atmosphere — and none had been detected surviving re-entry. He indicated that debris appeared unlikely to pose a problem.

"Thus far we’ve seen nothing larger than a football," he said, referring to debris in the atmosphere spotted by radar and other sensors.

The military concluded that the missile had successfully shattered the satellite because trackers detected a fireball. Cartwright said it was unlikely that the fireball could have been caused by anything other than the hydrazine in the tank.

And Cartwright cited two other sources of information that indicate the fuel tank was hit: the appearance of a vapor cloud and the results of spectral analysis, or the study of light emissions, from devices aboard two aircraft that operate from the Pacific test range associated with the Pentagon’s missile defense testing.

Debris from the satellite has started re-entry and will continue through Thursday and into Friday, Cartwright said.

The size of the debris is smaller than the Pentagon had forecast, and most of the satellite’s intelligence value was likely destroyed, Cartwright said. Analysts had said one of the reasons for the shootdown was that officials worried that without it, larger chunks of the satellite could fall and be recovered, opening the possibility of secret technology falling into the hands of the Chinese or others.

Gates arrived in Hawaii less than two hours before the missile was launched. His press secretary, Geoff Morrell, said Gates had a conference call during his flight with Cartwright and Air Force Gen. Kevin Chilton, head of Strategic Command. They told him that "the conditions were ripe for an attempt, and that is when the secretary gave the go-ahead to take the shot, and wished them good luck," Morrell said.

At 10:35 p.m. ET, Gates spoke to both generals again and "was informed that the mission was a success, that the missile had intercepted the decaying satellite, and the secretary was obviously very pleased to learn that," said Morrell.

Associated Press writer Pauline Jelinek contributed to this report from Washington.

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