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A ball of ice 100 kilometres across is the most widely travelled member of
the Solar System. The object, 1999 CF119, was spotted by astronomers at the
University of Hawaii. Its path has now been calculated by Brian Marsden of the
Harvard-Smithsonian Center for Astrophysics in Massachusetts, who says it takes
1200 years to complete an orbit that takes it 30 billion kilometres from the
Sun. The only objects with more distant orbits are the long period comets, which
are not regarded as members of the Solar System.