A piece of Sir Isaac Newton's apple tree is set to defy gravity, the theory it inspired, by being carried into space on the next NASA shuttle mission. The wood sample is from the original tree from which an apple fell, leading Newton to devise his theory of gravity. <br/><br/>The sample, which is normally held in the Royal Society's archives, was lent to British-born astronaut Dr Piers Sellers, who will take it into orbit. The tree sample will be accompanied on its trip into space by an image of Sir Isaac, which was also donated by the Royal Society. <br/><br/>The move is part of the Royal Society's 350th anniversary celebrations. The Atlantis shuttle carrying six crew members will lift off on 14 May. The 12-day mission is expected to be the Nasa shuttle's last.