When was pluto not a planet anymore?

Pluto was discovered on February 18, 1930 by Clyde Tombaugh. Clyde Tombaugh was only 24 years old when he made the discovery.

For 76 years, Pluto resigned as the ninth planet in our solar system. In 2006, everything changed. Pluto was reclassified as a dwarf planet.  Astronomers decided to classify Pluto as a dwarf planet because it's very far away and too small.