Re: Damn! There goes one hell of a telescope...



Rich wrote:

BBC NEWS
US plans to shoot down satellite
The US military is planning to shoot down a broken spy satellite due
to crash land on Earth in the next few weeks, the Pentagon has
announced.

President George W Bush approved the option to fire a missile from a
US Navy ship to destroy the satellite before it enters the atmosphere,
officials said.

They say the satellite contains a hazardous material which could be
fatal if inhaled by humans.

A US general denied claims that the main aim was to destroy secret
parts.

General James Cartwright said confidential components would be burned
up in the atmosphere and, in any case, that would not be a reason for
shooting down the satellite.

We are better off taking the attempt than not
General James Cartwright

He said the National Reconnaissance Office "bird", launched in
December 2006, had lost power and communications shortly after it
entered space and a controlled re-entry was not possible.

The broken satellite had been predicted to reach the top of the
Earth's atmosphere towards the end of February or early March and
officials could not predict where it would land.

The general said the window of opportunity for the strike would open
in the next three or four days and last for about a week.

Burning sensation

Deputy National Security Adviser James Jeffries said thousands of
space objects fell to Earth each year, without threat to humans.

BROKEN SATELLITE
Owner: National Reconnaissance Office satellite
Mission: Classified
Launched: Dec 2006
Weight: 5,000lb (2,270 kg)
2,500lb could survive re-entry
Carrying hydrazine rocket fuel

"What makes this case is a little bit different... was the likelihood
that the satellite upon descent to the Earth's surface could release
much of its 1,000lb plus (454 kg) of its hydrazine fuel as a toxic
gas," he said.

He said it was unlikely to hit a populated area, but "there was enough
of a risk for the president to be quite concerned about human life".

The hydrazine rocket fuel, which would have been used up had the
satellite been operational, is in a tank that would survive re-entry.

Gen Cartwright said that exposure to the hydrazine would have similar
effects to inhaling chlorine or ammonia - a burning sensation in lungs
and, if too close and too much, then possibly death.

If the hydrazine tank did burst, the danger zone would be an area
covering the size of two football pitches. He said that blowing the
satellite up would disperse the hydrazine harmlessly in space, leaving
only small-scale satellite debris to fall harmlessly to Earth.

One shot

The US Navy plans to modify a Standard Missile 3 to be launched from
an Aegis destroyer - usually part of the US Missile Defense System
designed to intercept ballistic missiles.

Gen Cartwright said they planned to have one missile shot, but there
would be three missiles available on three ships. If the first attempt
was unsuccessful, a decision would be made whether a second attempt
was required.

It must be done before it re-enters the Earth's atmosphere, otherwise
the craft would be "next to impossible" to hit because of atmospheric
disturbances.

"We are better off taking the attempt than not," Gen Cartwright said.

The general added that the space shuttle, currently on a mission to
the International Space Station, would be back on Earth before the
attempt was made.

China test

The largest uncontrolled re-entry by a US space agency (Nasa) craft
was the abandoned Skylab space station in 1979.

Last year, China carried out a test using a ground-based ballistic
missile to destroy a satellite in space, prompting international alarm
and fears of a space arms race.

Gen Cartwright said there was no parallel with Beijing's actions as
the Chinese satellite had been much further out from Earth, meaning
its debris could be floating round for decades, endangering
spacecraft.

good test of intercept targeting, while propagandists sleep in
Toronto. Sleep well.



.

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