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APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Solar System Object Larger than Pluto Discovered
Explanation: Is that a tenth planet? A faint, slowly moving dot discovered by computer shows clear signs of being a deep Solar System object at least as large as Pluto . The object, designated 2003 UB 313 , is currently situated nearly 100 times the Earth-Sun distance -- over twice the average Pluto-Sun distance. That far out, the only way a single round object could be as bright as 2003 UB 313 would be if it is at least as large as Pluto and completely reflective . Since 2003 UB 313 is surely not completely reflective , it could be substantially larger. One of the discovery frames is shown above digitally expanded and artificially brightened. 2003 UB 313 was identified initially on frames taken by the automated 1.2-meter Samuel Oschin Telescope at Palomar Observatory in California, USA.
| Date | July 31, 2005 |
|---|---|
| Credit | Credit: M. Brown ( Caltech ), C. Trujillo ( Gemini ), D. Rabinowitz ( Yale ), NSF , NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |