Sunday, January 27, 2008

Threat as 10-ton satellite set to crash back to Earth

A LARGE American spy satellite has lost power and is expected to crash back to Earth sometime late next month.

The 10-ton satellite’s controllers admit that they do not know where it might come down and they have no way of controlling the return of a vehicle which may contain hazardous materials.

“Numerous satellites over the years have come out of orbit and fallen harmlessly,” said Gordon Johndroe, a spokesman for the US National Security Council. “We are looking at all potential options to mitigate any possible damage that this satellite may cause.” Governments around the world have been warned of the satellite’s plight.

The spokesman refused to speculate on the possibility that the satellite may be shot down by a missile to prevent any debris causing damage.

If the US government elected not to use that method to destroy the errant satellite, then it could opt instead to employ America’s new laser weapons for use against incoming missiles, which are now being tested on board a modified Boeing jumbo jet.

Falling satellites and their trajectories can usually be predicted well in advance and airlines notified. The lack of certainty over the reentry location of this dying spy in the sky, not to mention the risk from any poisonous materials that it may be carrying, underlines the threat the satellite poses as it plunges from its orbit 100 miles above the Earth.

Last year 270 passengers on board an airliner above the Pacific had a lucky escape when the wreckage of a blazing Russian satellite narrowly missed their aircraft.

Pilots of the Latin American Airbus A340 saw the fiery debris streaking through the darkness directly ahead of them. The wreckage caused a sonic boom, which temporarily drowned out the noise of the jet’s four engines.

The near-disaster happened about four hours southwest of Auckland, New Zealand, and air traffic controllers quickly realised that the flaming wreckage was what remained of a communications satellite that had not been due to enter the Earth’s atmosphere for a further 12 hours. The Pacific area is favoured for bringing satellites to Earth because of the relatively light population.

The largest uncontrolled reentry of a Nasa spacecraft from space orbit was Skylab, the 78-ton space station that fell back to Earth in 1979. The debris from the station fell across the Indian Ocean and a remote part of Western Australia. There were no reported injuries or damage from Skylab.

In 2000 Nasa engineers successfully directed a safe return from orbit of the 17-ton Compton Gamma Ray Observatory using rockets on board the satellite to bring it down in a remote part of the Pacific.

The difficulty or predicting reentry was reinforced two years later when debris from a science satellite crashed onto the Earth’s surface several thousand miles from where it had been expected to impact. Elements of the 7,000lb satellite rained down over the Gulf. Fortunately there was no reported injury to life or property.

The most dangerous satellite disaster came in January 1978 when a fireball streaked through the skies of western Canada, heralding the demise of a Russian spy satellite.

The remains of the satellite came down over Great Slave Lake and fell across the North West Territories, Alberta and Saskatchewan spreading mildly toxic radioactive waste.

In the subsequent furore the then Canadian prime minister, Pierre Trudeau, accused the United States of failing to warn the Ottawa government of the impending danger.

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