"10th Planet" Proves Bigger than Pluto
Scientific American
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German astronomers working in Spain have determined that UB313, the tenth planet has a diameter of roughly 3,000 kilometers--roughly 700 kilometers larger than Pluto's.
When astronomers discovered UB313 a little more than a year ago, they had a hunch it might be bigger than Pluto because of its brightness.
But despite several attempts to observe more closely the mysterious object orbiting the sun at a distance of more than 14 billion kilometers, accurate estimates of its size remained elusive. Until now.
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See Also:
Why Santa transforms our solar system
Distant world tops Pluto for size
Pluto may lose status as planet
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Frank Bertoldi of the University of Bonn in Germany and his colleagues used the IRAM 30-meter telescope in the Sierra Nevada mountains of southern Spain to observe UB313 in the infrared range.
Because visual brightness alone is not an accurate indicator of size--it could result from the body's surface being either actually large or mirrorlike--the researchers made observations in wavelengths longer than those of visible light.
Based on observations made over nine nights in August 2005, the team reports, UB313 appears to have a diameter of between 3,094 and 2,859 kilometers. Even the smallest size in that range would make the candidate planet's diameter more than 500 kilometers larger than Pluto's.
Feb 02, 2006
Scientific American
_____________
German astronomers working in Spain have determined that UB313, the tenth planet has a diameter of roughly 3,000 kilometers--roughly 700 kilometers larger than Pluto's.
When astronomers discovered UB313 a little more than a year ago, they had a hunch it might be bigger than Pluto because of its brightness.
But despite several attempts to observe more closely the mysterious object orbiting the sun at a distance of more than 14 billion kilometers, accurate estimates of its size remained elusive. Until now.
________________
See Also:
Why Santa transforms our solar system
Distant world tops Pluto for size
Pluto may lose status as planet
________________
Frank Bertoldi of the University of Bonn in Germany and his colleagues used the IRAM 30-meter telescope in the Sierra Nevada mountains of southern Spain to observe UB313 in the infrared range.
Because visual brightness alone is not an accurate indicator of size--it could result from the body's surface being either actually large or mirrorlike--the researchers made observations in wavelengths longer than those of visible light.
Based on observations made over nine nights in August 2005, the team reports, UB313 appears to have a diameter of between 3,094 and 2,859 kilometers. Even the smallest size in that range would make the candidate planet's diameter more than 500 kilometers larger than Pluto's.
Feb 02, 2006
