P is for Pluto--
Ah, poor pluto. The farthest planet from earth, wait...not only is it lonely out there, it was demoted to a "dwarf planet."
"In essence, the term is meant to designate any planetary-mass object that is neither a planet nor a natural satellite that fits two basic criteria. For one, it must be in direct orbit of the Sun and not be a moon around another body. Second, it must be massive enough for it to have become spherical in shape under its own gravity. And, unlike a planet, it must have not cleared the neighborhood around its orbit." ~Universe Today
Click on the link to visit other participants in the A to Z Challenge. I'm currently #583