Why is Pluto not a planet?
What happend to Pluto? Why is Pluto no longer a planet?
Pluto was a planet from 1930-2006. The body mass called Pluto is still there, but it is simply not considered a planet anymore.
Back when we went to school, we learned that there were 9 planets, one of them being Pluto. However, these days, Pluto is no longer considered a planet.
Pluto is now considered to be a dwarf planet, like tons of other masses floating around in space.
So why is Pluto not a planet anymore? Pluto is no longer a planet, because scientists changed the definition of a planet.
To be a planet, the following criteria must be met:
1) It must orbit around the sun.
2) It must dominate the neighborhood around its orbit.
3) It must be large enough to become round, because of if its own gravity.
Pluto is certainly round and it does orbit around the sun, but it does not dominate its neighborhood. It does not suck in debris or is substantial larger than its moon. Basically, it is too small to be a planet. It is too small to control its environment with its mass and gravity.
Pluto was discovered in 1930 by Clyde W. Tombaugh at the Lowell Observatory in Flagstaff Arizona and named by an 11- year-old girl from England, named Venetia Burney. Venetia lived until 2009 and thus outlived Pluto as a planet.
Pluto is named after a Roman God and not a Disney dog.
PS. Eris, another dwarf planet in our solar system, is actually larger than Pluto.