A European spacecraft is moving closer to an icy comet more than 250 million miles away - bringing a 10-year journey across the solar system.to an end.
The Rosetta probe will be thrusted to within 100km of the two-mile wide object at 10am, UK time.
Since launching in March 2004, Rosetta has travelled more than dour billion miles across the asteroid belt and more than five times the Earth's distance from the Sun.
It is due to be propelled near the comet 67P/Churyumov-Gerasimenko - a misshapen lump of ice and dust.
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