Eventually,Pluto lost status as planet. International Astronomical Union(IAU) decided to cut off Pluto from the group of the solar system. As the newest study of the planetary movements advanced most of astronomers thought that Pluto is different from another eight planets.
We were used to nine planets for long time. So I feel strange that Pluto is not planet.(^^;
By the way,do you know that the Dysney's character Pluto was named from the planet Pluto?