Pentagon Opens Window of Time to Shoot Down Satellite

By Gerry J. Gilmore
American Forces Press Service

Feb. 20, 2008 - The Pentagon has opened the window of time in which it will shoot down a malfunctioning U.S. reconnaissance satellite, a senior U.S. military officer said here today. Today's return of the space shuttle Atlantis to Earth prompted the start of the optimal time period for shooting down the satellite, which extends until about the end of the month, the senior officer told Pentagon reporters.

Only "tens of seconds" will be available each day for a favorable launch of a ship-based SM-3 interceptor missile, the senior officer said. "The window is small, ... but we're looking for the best orientation of the satellite" before launching the missile, the officer explained.

The 5,000-pound satellite malfunctioned soon after it was launched in 2006, making it unresponsive to ground control. It is carrying a tank full of hydrazine, a toxic rocket fuel. The satellite, orbiting every 90 minutes or so, was expected to fall to Earth in February or March with its tank of hydrazine intact, possibly endangering human populations.

President Bush directed the Defense Department to engage the satellite just before it enters the atmosphere at about 150 miles above the Earth. The goal is for the missile to hit and rupture the tank of rocket fuel, causing the hydrazine to burn up harmlessly in the atmosphere, along with debris from the stricken satellite.

About 50 percent of debris produced by the missile strike is expected to burn up during the stricken satellite's first two orbits after being hit, the senior military officer said, with the rest burning up shortly after. The strike is designed to leave no space debris.

Defense Secretary Robert M. Gates is to give the order to launch, based upon commanders' recommendations, the senior officer said. Gates will be advised as to the optimal time to launch by the commander of U.S. Strategic Command, based at Offutt Air Force Base, in Omaha, Neb.

All space sensor and missile-tracking activity related to the missile launch is being coordinated by the Joint Space Operations Center, at Vandenberg Air Force Base, Calif. Sensors, such as large radars and telescopes, are being coordinated by the Joint Integrated Missile Defense Team in Colorado Springs, Colo., under the U.S. Army's Space and Missile Defense Command.

Three U.S. Navy ships -- the cruiser USS Lake Erie and the destroyers USS Decatur and USS Russell -- are posted in the Pacific Ocean waiting for an optimal time to launch, the senior officer said. The Erie is slated to shoot at the satellite, and it is fitted with two SM-3 missiles. The Decatur has one, and the Russell has none. The missiles were modified to carry additional sensor equipment for the mission, the senior officer said.

The launch will be conducted during daytime over the Pacific, the senior officer explained, so that all sensors involved can better track the results of the missile launch. Necessary criteria for launch include satisfactory alignment of all pre-launch sensor-supplied data, as well as favorable weather conditions, he said.

Currently, the wave height about the ships is unfavorable to launch, the officer said. However, this and other conditions are subject to change, he added.