Pluto

Pluto is the dwarf planet in the solar system. If it was considered to be the 9th and final planet.

Location Summary
When the Little Einsteins sang the planet song for the third time, they have count all 8 planets while Pluto was hiding behind Neptune.

Appearances in this show

 * A Galactic Goodnight

Trivia

 * Pluto is no longer considered to be a planet.
 * Other dwarf planets are Ceres, Haumea, Makemake, and Eris.