PLUTO
Although stripped of its planet status in 2006, ( it is now believed to be a part of the Kuiper belt ) I chose to include Pluto out of childhood sentimentality (or childish recalcitrance, take your pick.)  Thought of as the most remote and distant of the planets, the orbit of Pluto actually takes it closer to the sun than Neptune, as the paths of those two bodies cross every few years.  The discovery of Pluto was due to an error to start with: flawed calculations predicted another planet beyond Neptune.  The numbers were wrong: they didn't have the right mass for Neptune.  But there was indeed another orbiting body, Pluto! 
Poor little Pluto.  I still love ya!

The model for Pluto is
Morf-stock and the rest is from NASA.
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