* Astronomy

Sir Ranulph Fiennes' 'coldest journey' begins

Sir Ranulph Fiennes is leading a team of five other explorers in a quest to achieve a feat no other human has managed - to walk across Antarctica in the near permanent darkness and super low temperatures of winter.
Phase one of The Coldest Journey expedition - which aims to raise millions of pounds in donations for the Seeing is Believing charity to tackle avoidable blindness - begins later when the icebreaker SA Agulhus sets off from the River Thames.
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