Where do old satellites go to die?

Disabled spy satellite threatens Earth
Eileen Sullivan, Associated Press Yahoo News 27 Jan 08;

[wild comment: it is 'harmless' if the satellite falls into the ocean, but 'threatens Earth' if it doesn't?]

A large U.S. spy satellite has lost power and could hit the Earth in late February or early March, government officials said Saturday.

The satellite, which no longer can be controlled, could contain hazardous materials, and it is unknown where on the planet it might come down, they said. The officials spoke on condition of anonymity because the information is classified as secret. It was not clear how long ago the satellite lost power, or under what circumstances.

"Appropriate government agencies are monitoring the situation," said Gordon Johndroe, a spokesman for the National Security Council, when asked about the situation after it was disclosed by other officials. "Numerous satellites over the years have come out of orbit and fallen harmlessly. We are looking at potential options to mitigate any possible damage this satellite may cause."

He would not comment on whether it is possible for the satellite to perhaps be shot down by a missile. He said it would be inappropriate to discuss any specifics at this time.

A senior government official said that lawmakers and other nations are being kept apprised of the situation.

The spacecraft contains hydrazine — which is rocket fuel — according to a government official who was not authorized to speak publicly but spoke on condition of anonymity. Hydrazine, a colorless liquid with an ammonia-like odor, is a toxic chemical and can cause harm to anyone who contacts it.

Such an uncontrolled re-entry could risk exposure of U.S. secrets, said John Pike, a defense and intelligence expert. Spy satellites typically are disposed of through a controlled re-entry into the ocean so that no one else can access the spacecraft, he said.

Pike also said it's not likely the threat from the satellite could be eliminated by shooting it down with a missile, because that would create debris that would then re-enter the atmosphere and burn up or hit the ground.

Pike, director of the defense research group GlobalSecurity.org, estimated that the spacecraft weighs about 20,000 pounds and is the size of a small bus. He said the satellite would create 10 times less debris than the Columbia space shuttle crash in 2003. Satellites have natural decay periods, and it's possible this one died as long as a year ago and is just now getting ready to re-enter the atmosphere, he said.

Jeffrey Richelson, a senior fellow with the National Security Archive, said the spacecraft likely is a photo reconnaissance satellite. Such eyes in the sky are used to gather visual information from space about adversarial governments and terror groups, including construction at suspected nuclear sites or militant training camps. The satellites also can be used to survey damage from hurricanes, fires and other natural disasters.

The largest uncontrolled re-entry by a NASA spacecraft was Skylab, the 78-ton abandoned space station that fell from orbit in 1979. Its debris dropped harmlessly into the Indian Ocean and across a remote section of western Australia.

In 2000, NASA engineers successfully directed a safe de-orbit of the 17-ton Compton Gamma Ray Observatory, using rockets aboard the satellite to bring it down in a remote part of the Pacific Ocean.

In 2002, officials believe debris from a 7,000-pound science satellite smacked into the Earth's atmosphere and rained down over the Persian Gulf, a few thousand miles from where they first predicted it would plummet.

Associated Press writers Pamela Hess and Deb Riechmann contributed to this report.

Satellite unlikely to pose danger to humans
Andrea Shalal-Esa Yahoo News 29 Jan 08;

A disabled U.S. spy satellite is likely to break into small pieces when it falls to Earth within weeks, posing little danger to humans, U.S. government officials and space experts said on Monday.

Most, if any, debris that survives the intense heat of re-entry would likely fall into the oceans, which cover more than 70 percent of the Earth, White House National Security Council spokesman Gordon Johndroe said.

But he said the U.S. government was monitoring the satellite's descent from orbit and examining different options to "mitigate any damage."

The U.S. military could potentially use a missile to destroy the minivan-sized satellite in space, but one senior U.S. defense official said that was unlikely for several reasons, including concern about creating space debris as China did when it shot down one of its satellites last year.

"Given that 75 percent of the Earth is covered in water and much of the land is uninhabited, the likely percentage of this satellite or any debris falling into a populated area is very small," Johndroe said.

Pentagon spokesman Bryan Whitman said more than 17,000 man-made objects re-entered the Earth's atmosphere over the past 50 years without major incident.

"We are monitoring it ... we take our obligations seriously with respect to the use of space," Whitman said, noting the satellite was expected to return to earth "over the next several weeks ... late February, early March."

SATELLITE LAUNCHED IN 2006

The satellite is a classified National Reconnaissance Office spacecraft launched from Vandenberg Air Force Base in California in 2006, according to four senior U.S. officials, who asked not to be named.

The satellite, known as L-21, has been out of touch since shortly after reaching its low-Earth orbit. Built by Lockheed Martin Corp at a cost of hundreds of millions of dollars, the satellite has fallen more than 70 km (43 miles) to an orbit at around 280 km (174 miles) above the Earth. U.S. and European astronomers estimate it is dropping at an accelerating rate of some 8 km (5 miles) a day.

Because the satellite never became operational, it has toxic rocket fuel on board that would have been used to maneuver the satellite in space. It could pose a danger if the fuel tank does not explode upon re-entry.

Thousands of space objects fall to Earth each year, but they generally scatter over a huge area and there have never been any reported injuries, two U.S. officials said.

Occasionally, bigger objects survive, including a 563-pound (255-kg) stainless steel fuel tank from a Delta II rocket that landed 50 yards from a farmer's home in Texas in 1997.

This L-21 satellite is much smaller, and more likely to burn up as it enters the atmosphere, scientists said.

The U.S. military has no weapon designed to shoot down a satellite, but it demonstrated the ability to do that in the mid-1980s, and could cobble together a plan to do so again fairly quickly, said the senior defense official.

Such a move appears unlikely, given global dismay about China's use of a missile to destroy a much bigger satellite at a higher orbit, which scattered nearly 1,000 pieces of debris throughout space, the official said.

(Additional reporting by Andrew Gray)