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...with SM-3s? Whoa...
http://www.msnbc.msn.com/id/23166344/
http://www.msnbc.msn.com/id/23166344/
Pentagon to shoot down broken spy satellite
Plan is to fire missiles from U.S. Navy cruiser before it hits Earth
MSNBC News Services
updated 10:33 a.m. PT, Thurs., Feb. 14, 2008
WASHINGTON - The Pentagon is planning to shoot down a broken spy satellite expected to hit the Earth in early March, The Associated Press has learned.
U.S. officials said Thursday that the option preferred by the Bush administration will be to fire missiles from a U.S. Navy cruiser, and shoot down the satellite before it enters Earth's atmosphere.
The officials spoke on condition of anonymity because the options have not yet been discussed publicly. Deputy national security advisor James Jeffries, Gen. James Cartwright, Joint Chiefs of Staff vice chairman, and NASA administrator Michael Griffin will hold a press conference at 2:30 p.m. EST to discuss the satellite.
The disabled satellite is expected to hit the Earth the first week of March. Officials said the Navy would likely shoot it down before then, using a special missile modified for the task.
The Navy will fire two or three SM-3 missiles from a cruiser and destroyer off the Northwest coast of Hawaii. The SM-3's which are more of a medium-range interceptor have to be modified — more fuel and new software — to reach the disabled spy satellite in orbit. If the intercept and kill are successful and the satellite is destroyed, it appears most of the debris will become orbitting "space junk" and not reenter Earth's atmopshere.
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 United States and other countries.
A key concern at that time was the debris created by the 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. But officials familiar with the situation say about half of the 5,000-pound 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.
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.
Air Force Gen. Gene Renuart, who heads U.S. Northern Command, told The Associated Press in late January that the size of the satellite suggests that some number of pieces will not burn up as the orbiting vehicle re-enters the Earth's atmosphere and will hit the ground.
"We're aware that this satellite is out there," Renuart said. "We're aware it is a fairly substantial size. And we know there is at least some percentage that it could land on ground as opposed to in the water."
A U.S. official confirmed that the spy satellite, which lost power and no longer can be controlled, was launched in December 2006. It carried a sophisticated and secret imaging sensor but the satellite's central computer failed shortly after launch.
The official, who spoke on condition of anonymity because the information is classified as secret, said the satellite is designated by the military as US 193, but it never reached its final orbit and the Pentagon declared it a total loss in early 2007.
Renuart added that, "As it looks like it might re-enter into the North American area," then the U.S. military along with the Homeland Security Department and the Federal Emergency Management Agency will either have to deal with the impact or assist Canadian or Mexican authorities.
Military agencies, he said, are doing an analysis to determine which pieces most likely would survive re-entry. But he cautioned that officials won't have much detail on where or when it will crash until it begins to move through the atmosphere and break up.
Renuart added that there does not as yet appear to be much concern about sensitive technologies on the satellite falling into enemy hands.
"I'm not aware that we have a security issue," he said. "It's really just a big thing falling on the ground that we want to make sure we're prepared for."
The satellite includes some small engines that contain a toxic chemical called hydrazine — which is rocket fuel. But Renuart said they are not large booster engines with substantial amounts of fuel.
Initial estimates were that the satellite would take years to degrade and re-enter the atmosphere.
Video images of the satellite captured by John Locker, a British amateur satellite watcher, show it to be about 13 feet to 16.5 feet across. Locker calculated its size with data on its altitude and location provided by other amateur satellite watchers, using the international space station as a yardstick.
Satellite watchers — a worldwide network of hobbyists who track satellites for fun — have been plotting the satellite's degradation for a year. They estimated it at an altitude of about 173 miles in late January, and Locker believes it is dropping about 1,640 feet a day.
Where it lands will be difficult to predict until the satellite falls to about 59 miles above the Earth and enters the atmosphere. It will then begin to burn up, with flares visible from the ground, said Ted Molczan, a Canadian satellite tracker. From that point on, he said, it will take about 30 minutes to fall.
In the past 50 years of monitoring space, 17,000 manmade objects have re-entered the Earth's atmosphere.
NBC News contributed to this report by The Associated Press.
URL: http://www.msnbc.msn.com/id/23166344/