Planet X? - Distant object found orbiting Sun
Astronomers have found a large object in the Solar System's outer reaches. It is being hailed as "a great discovery".
Details of the object are still sketchy. It never comes closer to the Sun than Neptune and spends most of its time much further out than Pluto. It is one of the largest objects ever found in the outer Solar System and is almost certainly made of ice and rock. It is at least 1,500km (930 miles) across and may be larger than Pluto, which is 2,274km (1,400 miles) across. The uncertainty in estimates of its size is due to errors in its reflectivity. It might be a large, dim object, or a smaller, brighter object. Whatever it is, astronomers consider it a major discovery. In 2004 scientists discovered Sedna, a remote world that is 1,700 km across.
Read the article at http://news.bbc.co.uk/2/hi/science/nature/4726733.stm
