Theory of Pluto's Disruption of Orbit Several hundred millennia ago, Pluto was originally a miniscule satellite (about 75%-65% of it's current mass) of larger Neptune when a comet (being 6/8 of the mass of pre-collision Pluto) struck Pluto with as much force to push Pluto out of orbit around Neptune, about 350 million kilometres before both planets make a second meet. This initiating force results in Pluto unusual, eccentric orbit path extending far beyond Neptune's. The dust, debris, ice and shattered center left floating after the impact was captured by Pluto's gravitational field. The floating ice and debris then collected on the shattered pieces of the comet which then shaped the fragments into spherical balls which then became Pluto's moons, Nix, Hydra, and the largest being Charon. It is unknown whether the crater is still remaining on Pluto due to in sufficient imaging (which could possibly be the dark spot in the images.