High confidence a missile cruiser hit satellite fuel tank
The Pentagon said on Thursday it had "a high degree of confidence" that a Navy missile hit the toxic fuel tank of a disabled US spy satellite, which posed a potential threat if it struck land on reentry.
But Marine Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, told reporters it could take another 24-48 hours to know for sure that the tank containing hydrazine fuel had been destroyed.
An SM-3 missile fired from the guided-missile cruiser USS Lake Erie in the Pacific Ocean northwest of Hawaii hit the errant satellite on Wednesday at 10:26 p.m. EST, 153 nautical miles above the Earth.
Washington says its aim is to prevent harm to humans from the satellite's tank of hazardous hydrazine fuel.
Cartwright said there was nearly a 90 percent chance that the tank had been breached in the collision.
"We're very confident that we hit the satellite. We also have a high degree of confidence that we got the tank," Cartwright said at a Pentagon briefing.
"From our position, you always want to hedge your bet because there's no absolute certainty."
Justification questioned
The missile hit the 5,000-pound (2,270 kg), bus-sized satellite as it traveled through space at more than 17,000 miles per hour (27,400 kph), the Pentagon said.
"Due to the relatively low altitude of the satellite at the time of the engagement, debris will begin to re-enter the earth's atmosphere immediately," it added.
"Nearly all of the debris will burn up on reentry within 24-48 hours and the remaining debris should re-enter within 40 days."
Some space experts have questioned the Pentagon's justification for the mission, saying the chances of any part of the satellite causing harm were extremely remote.
But Pentagon officials have denied suggestions they wanted to destroy the satellite to prevent part of the classified spacecraft from falling into the hands of rival powers.
They also reject accusations from some security and space experts that the Pentagon was using the satellite problem as an excuse to test and demonstrate its ability to hit targets in space.
During a flight from Washington to Hawaii, US Defense Secretary Robert Gates authorized the Navy to fire the missile, about 10 hours before the operation was carried out, Pentagon press secretary Geoff Morrell said.
The Pentagon has said the stray spacecraft was a test satellite for the National Reconnaissance Office, a US intelligence agency, launched in December 2006.
It stopped communicating within a few hours of reaching orbit, Pentagon officials have said.
The Pentagon has said the operation would use modified elements of its missile defense system.
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