Pluto; a proto planet in transition

Pluto; a proto planet in transition

Pluto is one of thousands of planetesimal sized Trans-Neptunian bodies. For the last few years there has been a raging debate as to whether Pluto is a planet or not. As Pluto is orbit about the sun, it can be considered a planet, except for its diminutive size, which is why it was "demoted". Pluto has a companion, Charon, which one can say is a moon of Pluto. In reality, Charon is another planetesimal which happens to be in orbit around Pluto and shares the same relationship with Pluto. Pluto is caught in a curious two to three resonance with Neptune, which stabilizes its orbit, because it never gets close enough to Neptune to be pulled into or ejected out of the solar system. For every three of Neptune's orbits, Pluto and Charon orbit twice. Pluto belongs to the family of inner Kuiper Belt objects.

Pluto represents the seed of another type of body. It is neither rocky planet nor a gas giant planet. It is made up of volatiles like methane, ammonia, water ice and other hydrocarbons. These molecules were too far out to be collected by the gas giants and their moons. By accretion stages that are identical to those forming the Earth and the other major planets, Pluto, Charon, Sedna and thousands of others are slowly growing in size. They are still under evolution. What remains is competition for material by absorbing smaller planetesimals. Due to their distance from the sun and their as yet weak gravitational influence, their evolution takes billions of year as opposed to the millions it took to form the terrestrial inner planets.
http://syzygyastro.hubpages.com/hub/What-Pluto-Really-Is