Pluto THE DWARF PLANET

What happened to Pluto?  In 2006, Scientists decided that Pluto was no longer one of the 9 planets.  Pluto has a different shaped orbit than the other 8 planets.  It goes into Neptune’s orbit and stays there for 20 years. This happens every 248 years.

Pluto: A True Outer Planet or Not?  Pluto is NOT a true planet because:  1) Pluto is composed of rock and metal (similar to inner planets) and not made of hydrogen and helium like the outer planets.  2) Pluto doesn’t have a ring like the other 4 outer planets.  3) Pluto is too small.

Naming Pluto  The name Pluto was suggested by Venetia Burney of England, who was 11 years old at the time. She suggested the name to her grandfather, who was Librarian at Oxford. He passed her idea to the astronomers who were trying to name the newly-discovered planet.  It is named after the Roman God of the Underworld, Hades.

Discovery  Pluto was discovered in 1930 by an astronomer named Clyde Tambaugh in Flagstaff, Arizona in the Lowell Observatory.