US satellite may crash to Earth in weeks: source

A large out-of-control U.S. spy satellite has lost power and may fall to Earth sometime in February or March, a U.S. government official warned on Saturday.

The satellite, which may contain hazardous material, can no longer be controlled and it was not known where on the planet it might come down, the official, who spoke on condition of anonymity, said.

American politicians and world leaders are being kept abreast of the situation, the official said.

John Pike, director of the defense research group GlobalSecurity.org, estimated that the spacecraft weighs about 20,000 pounds (9,000 kilograms) and is the size of a small bus.

"Appropriate government agencies are monitoring the situation," said National Security Council spokesman Gordon Johndroe.

"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 added.

In recent years, NASA has safely brought defunct satellites back to Earth. In 2000, the space agency maneuvered the 'Compton Gamma Ray Observatory' to a splashdown in the Pacific Ocean.

This would not be the first time a large satellite has lost power and crashed uncontrollably into the atmosphere. The largest was in 1979, when Skylab, a 78-ton abandoned space station, lost control and fell from orbit.

It fell apart on re-entry, with the debris crashing harmlessly into the Indian Ocean and across an uninhabited part of Western Australia.