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A Mir something to worry about

01:00 Wed 03rd Jan 2001 |

By Anna Tobin

THE DINOSAURS�are said to have been wiped out�by a giant meteor that hit earth many millions of years ago and it is often muted that the human race could meet a similar fate in�thousands of years from now. Only recently, however, has it been considered that�we could actually be wiped out by man-made objects tumbling to earth from space.

This fear became all too real last week, when radio contact with the Russian space station Mir was lost. The world's public was kept largely in the dark about this, but governments were generally concerned that the unmanned 140-tonne satellite, the size of a football pitch, could plummet towards earth causing untold damage on impact.

The panic subsided when radio contact was established 20 hours later., but there is nothing to stop a similar situation occurring again. The earth's orbit is littered with technological communication equipment. When a satellite's solar panels lose alignment with the sun, it loses power. If the alignment is not rectified remotely from earth, it will fall out of orbit and begin a rapid descent towards us.

There are already two known instances of man-made satellite crashing into earth. A Soviet Union-owned satellite�hit northern Canada in 1978. No one was injured, but it scattered radioactive matter on impact.�In 1979, an American-made satellite met a similar fate over Western Australia.

On a more positive note, satellites can and have been safely brought back to earth. In the first mission of its magnitude, Russian space officials intend to send an unmanned cargo space craft to steer Mir back to earth on 28 February. The robot ship will tip Mir slowly out of orbit about 200 miles above earth and send it into the South Pacific Ocean about 1,000 miles from Australia. The majority of Mir is expected to burn up when it hits the earth's atmosphere, but bits of red-hot metal weighing up to 1,500 tonnes could fall to earth at supersonic speed.�

Is this the first time you realised the seriousness of the Mir situation Do you think we deserve to be kept better informed about the dangers posed by what we have launched into orbit Or, would you prefer not to know too much and put your faith in the powers�that be to keep the world safe Launch your opinions on The AnswerBank's message boards. Click here.

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