"You want to make sure that everybody understands exactly what actions are being taken so there are no misunderstandings and misperceptions and also to reassure people vis-à-vis treaty obligations," spokesperson Sean McCormack told reporters.
Shooting down a satellite is particularly sensitive because of the controversy surrounding China's anti-satellite test last year, when Beijing shot down one of its defunct weather satellites, drawing immediate criticism from the U.S. and other countries.
A key concern at that time was the debris created by Chinese satellite's destruction—and that will also be a focus now, as the U.S. determines exactly when and under what circumstances to shoot down its errant satellite.
The military will have to choose a time and a location that will avoid to the greatest degree any damage to other satellites in the sky.
Also there is the possibility that large pieces could remain and either stay in orbit where they can collide with other satellites or possibly fall to Earth.
It is not known where the satellite will hit. Officials familiar with the situation say about half of the 5,000-pound (2,270-kilogram) spacecraft is expected to survive its blazing descent through the atmosphere and will scatter debris—some of it potentially hazardous—over several hundred miles.
The officials spoke on condition of anonymity because of the sensitivity of the matter.
Not "War in Space"
The satellite is outfitted with thrusters—small engines used to position it in space. They contain the toxic rocket fuel hydrazine, which can cause harm to anyone who contacts it.
Officials have said there is about 1,000 pounds (450 kilograms) of propellant on the satellite.
Known by its military designation US 193, the satellite was launched in December 2006. It lost power and its central computer failed almost immediately afterward, leaving it uncontrollable. It carried a sophisticated and secret imaging sensor.
The military's Ballistic Missile Defense System, known as "Sea-Based Midcourse," could destroy the satellite just as it begins to re-enter the Earth's atmosphere, said James Lewis, a satellite expert at the Washington-based Center for Strategic and International Studies, a conservative think-tank.
That would undercut any international criticism of a "war in space," Lewis said, and reframe it as a ballistic missile defense exercise. He said it could also avoid the problem of creating a large debris field of satellite pieces that would continue to orbit.
The goal, said Lewis, would be to explode the satellite into small pieces that would mostly burn up as they re-enter the atmosphere.
Associated Press Writers Pauline Jelinek and Ted Bridis contributed to this report.
Copyright 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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