The picture above was taken from the New Horizons spacecraft when it flew by at some point last year. In 2006 Pluto was demoted from a planet to a dwarf planet and here’s why.
To be a planet you have to fulfil certain criteria, they don’t just let anybody in! They have to:
- Be large enough to form a spherical shape under the planets own gravity
- Orbit the sun (cannot be a moon of another planet)
- Have a clear orbital route (no other objects on the route)
The only one that Pluto does not satisfy is having a clear orbital route. The dwarf planet takes 248 earth years to orbit the sun so it won’t be clearing it anytime soon. Unfortunately you’re not a planet Pluto but you may re-apply for the position when you have cleared your orbit.
Although this is not included in the criteria to be classified as a planet, Pluto has an eccentric orbit on a different plane to the rest of the planets as below.
Pluto definitely stands out from the rest of the planets in this sense.