The comet 67P/Churyumov-Gerasimenko was discovered in 1969 by Kiev-based astronomer Klim Churyumov. He was examining a photograph of the comet Comas Solá taken by his colleague Svetlana Gerasimenko when he spotted another comet-like object at the edge of the picture. P67 is about three kilometres by five in size and rotates around its one axis once in about every 12 hours. It takes approximately six and a half years to complete one sun orbit and its distance from the sun varies from between 194 and 858 million kilometres. In preparation for the Rosetta mission, Churyumov-Gerasimenko, which is considered to be a 'dusty' comet, was inspected in detail by the Hubble Space Telescope. In March 2003, one of Hubble’s cameras took some 60 images so that astronomers could get a rough idea of the comet's shape, which is similar to a rugby ball.