Russia's failed Phobos-Grunt space probe heads to Earth (BBC)
By Jonathan Amos
Science correspondent, BBC News
Russia's failed Mars probe, Phobos-Grunt, is about to fall back to Earth - quite probably on Sunday.
The spacecraft has been losing altitude rapidly in recent days and will soon be pulled into the top of the atmosphere where it will be destroyed.
Phobos-Grunt weighed some 13 tonnes at launch, but very little of this mass should make it through to the surface.
Russian space agency (Roscosmos) estimates suggest perhaps only 200kg will survive the fiery plunge.
Orbital debris experts say there are large uncertainties in predicting re-entry events and it is currently not possible to forecast precisely when or where on Earth the final descent will occur.
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more: http://www.bbc.co.uk/news/science-environment-16491457
