Rest of the article: Radar stations around the world, including RAF Fylingdales in North Yorkshire, are tracking the object, but there is little
chance of predicting with any accuracy where the debris will fall. The spacecraft's orbit puts a great swath of the planet in its path between the
latitudes of 57 degrees north and south. Mainland Britain lies between 50 and 60 degrees north. The satellite spends more time at higher latitudes, so
there is a slightly higher risk in those regions.
Most likely by far is that the remains of the satellite will drop into the ocean, or be strewn across one of the planet's most desolate regions, such
as Siberia, the Australian outback or the Canadian tundra. Nasa put the odds of anyone being struck by a falling part of the spacecraft at one in
3,200. The individual risk to a particular person is much less – one in 3,200 multiplied by the billions that live under the satellite's flight
path. "The odds of you as an individual being hit by this are around one in 20 trillion," Dr Robert Massey of the Royal Astronomical Society told
the BBC.
There are no confirmed injuries from man-made space debris and no record of significant property damage from a falling satellite. An organisation of
major space agencies known as the Inter-Agency Space Debris Co-ordination Committee (IADC) is running back-to-back simulations to work out when, and
roughly where, the spacecraft's remains will impact.
If the IADC or the Ministry of Defence, via RAF Fylingdales, found that the UK was at risk, they would inform the Cabinet Office civil contingencies
committee, which is responsible for alerting the emergency services.
The UK Space Agency said in a statement: "The government continues to monitor the situation, share information nationally and at the local level.
[The] Public will be aware through any press interest, but the risk to the UK is considered to be low and we will continue to monitor if that changes
at any time.
"Due to uncertainties in predicting the rarefied atmosphere at these very high altitudes, the accuracy of re-entry prediction is of the order of 10%
of the remaining lifetime, so even on the last orbit revolution (90 minutes), there is a nine-minute prediction uncertainty. If an object was about to
fall on the UK we could only respond as we would in any other 'no notice event' such as a plane crash, at which time tried and tested procedures
would be undertaken by the emergency response services."
When Nasa's Skylab fell to Earth in 1979, the space agency put the risk of human injury at 1 in 152, because the odds of the defunct space station
striking a city were much higher. The partially controlled Skylab missed its expected impact site in South Africa and crash-landed in Australia.
Predicting where the debris will land is difficult for two main reasons. Unpredictable rises in the sun's activity warm the atmosphere and make it
expand, which causes the spacecraft to experience more drag and re-enter more quickly. Another problem comes from uncertainties in the tracking of how
the spacecraft disintegrates, which means that even just a few hours before impact, the corridor of the Earth's surface at risk will be several
thousand long.
UN agreements oblige governments to return any parts of a satellite that are found to the owner, in this case Nasa, which will have to bear the costs
of recovery. They also say a launching state shall be absolutely liable to pay compensation for damage on the Earth's surface or to aircraft.
Nasa urges anyone who suspects they have found debris from the spacecraft not to touch it and inform the local police. The satellite was launched in
1991 aboard the space shuttle Discovery and decommissioned in 2005.
Nasa says more than 22,000 objects larger than 10cm (4in) are currently tracked by the US Space Surveillance Network. Only about 1,000 of these
represent operational spacecraft; the rest are orbital debris. Most orbital debris is within 1,250 miles (2,000km) of Earth's surface, says the
agency, with the greatest concentrations found 500-530 miles (800-850km) up. During the past 50 years an average of one piece of debris fell back to
Earth each day.
I do not claim any of this, Credit goes to
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