It was nearer to the Sun than (*) Neptune for 20 years in the 20th century, but, because it doesn't clear the neighborhood around its orbit, a 2006 IAU reclassification "demoted" it.
Bodies that orbit this object include Kerberos and Styx, which were named in 2013. This Kuiper Belt object will be visited by the New Horizons probe in 2015. It was nearer to the Sun than (*) Neptune for 20 years in the 20th century, but, because it doesn't clear the neighborhood around its orbit, a 2006 IAU reclassification "demoted" it. Hydra, Nix, and Charon orbit, for 10 points, what dwarf planet, the former 9th planet of the solar system?
Bodies that orbit this object include Kerberos and Styx, which were named in 2013.
Pluto