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Written by spacetravel.org
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Sunday, 05 February 2006 22:14 |
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A new study confirms that UB313, the object also known as Xena, on the outer edge of the Solar System, is larger than Pluto.
Xena, which is sometimes three times as far from the Sun as Pluto, was discovered in 2003, and its discovery was made public in July 2005. From its brightness and distance, astronomers estimated that it must be slightly larger than Pluto.
Frank Bertoldi of the University of Bonn in Germany and his colleagues have calculated Xenas size more directly by measuring its light at a wavelength of 1.2 millimetres using a telescope array in the Spanish Sierra Nevada. Xena emits this radiation in response to being warmed by the Sun, regardless of the shininess of its surface.The amount of millimetre radiation suggests that Xena is about 3000 kilometres wide, 30% wider than Pluto.
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