The Upper Atmosphere Research Satellite (UARS)
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Satellite due to 'crash' on Earth

A defunct Nasa satellite weighing six tonnes is expected to crash to Earth some time on Friday evening, possibly hitting the UK.

Experts are warning that large chunks of it may come down without burning up in the atmosphere. Experts say they will get a more precise idea in the last 12 hours before the satellite is due to return.

The US space agency says the risk to life from the Upper Atmosphere Research Satellite (UARS) is 1 in 3,200.

Pallab Ghosh reports.

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