Post
by Dr. Skeptic » Sat Nov 11, 2006 12:57 am
I don't ever remembering reading anything pertaining to Puto's orbit that would cause it to leave the solar system. Where did you aquire that information?
Pluto (and Charon) fails as planet/moon because the barycenter of their orbits does not lie within either spheres' mass: the center of gravity of their local system can be located in the empty space between the two bodies.
In a planetary orbit swap, the planets would exchange positions in the solar system which would not be a disqualifier for planet status.
I don't believe that Pluto was part of the inner planetary system, as a quick overview this is the "safest" answer.
As our Sun merged from a protostar to an active star, strong solar winds force the accretion disk away, the lighter elements (H, He, O, C ...) were pushed farther, heaver elements (Fe, Ni, Cu, Zn ...) is in higher concentration closer to the Sun. The average density of the planets lessen as the distance from the Sun increases - Mercury = 5.427 g/cm³, Mars = 3.934 g/cm³, Neptune = 1.638 g/cm3. The Kuiper Belt appears to contain predominantly frozen H2O and light hydrocarbons, (including Pluto), that may have moved along the solar winds as gasses or as resididual interstellar "stuff" from our corner of the Milky Way.
Pluto may have been a somewhat large Kuiper Belt object that was caught-up in Neptune's gravitational field and "flung" out of the orbital plane increasing its rate of encounters with other Kuiper Belt objects increasing its size and it's moons. There is no evidence of Pluto having a large amount of heavier elements placing it's creation closer to the Sun.
Did I hit your question this time?
Speculation ≠ Science
Any suggestions? 
