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Name:   Evelyn
Status:   student
Age:   16
Location: N/A
Country: N/A
Date: 1999 - 2000

I have found multiple resources about Planet X. To this date, Dec. 19, 2000, is there concrete evidence that there is a tenth planet in our solar system? I have found resources that say there is and there isn't. One resource says that people belive that Planet X revolves around other stars and not around our sun. Can you please answer this to the best of your knowledge for I am very curious about this subject. Also, rumors are that Nasa has built a special telescope for this planet? How can anyone prove and provide concrete evidence about the discovery of Planet X? Thank you for your time.

Evelyn -

To the best of my knowledge Planet X is still in the theory stage. To satisfy me that it really exists, it would require finding an object that (in photos) moves against the backdrop of the stars of the galaxy and after plotting its changing positions and creating a mathematical description of the path... its trajectory will place it in orbit around the sun. Finding a planet is tough work!

There is also difficulty in defining a planet by size, position, and eccentricity of orbit. Some suggest that Pluto should not be considered a planet. It is very small and has a more eccentric orbit than any other planet. It does have a moon, though, and it seems to have a smoother surface than most asteroids.

You might find reading the history of the hunt for planet 9 (then called planet X). In particular, the work of Percival Lowell.

Larry Krengel

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