Since its discovery and classification as the ninth planet in our solar system in 1930, Pluto has been the subject of much controversy in the scientific community.  Its small size and extreme distance from Earth have made gathering specific data about its characteristics difficult, and no real consensus exists amongst astronomers about the information that is known about Pluto.  In 2006, the International Astronomical Union created an official definition for the term "planet" which listed three criteria for classification:

1. The object must be in orbit around the sun.
2. The object must be massive enough to be rounded into a sphere by its own gravity.
3. The object must have "cleared the neighborhood" around its orbit.

Because Pluto is much smaller than the other objects in its orbit, it fails to meet the third condition and has since been known as a "dwarf planet".  Some scientists have gone so far as to suggest that Pluto may actually be one of the many moons of its neighboring planet, Neptune.

When Pluto was first discovered in 1930, astronomers estimated that it may be as large as earth and thus were confident that it was, in fact, a planet.  As our ability to gather information about outer space continues to improve through more powerful telescopes and space probes, scientists are now able to use the new, more accurate information they receive to accurately classify objects in space.  While some still argue that Pluto meets the accepted criteria to be known as a planet, for the time being, conventional scientific thinking will hold that our solar system only has eight planets.

1 "Camelot—Camelot," said I to myself. 2 "I don't seem to remember hearing of it before… Name of the asylum, likely."

3 It was a soft, reposeful summer landscape, as lovely as a dream, and as lonesome as Sunday.  4 The air was full of the smell of flowers, and the buzzing of insects, and the twittering of birds, and there were no people, no wagons, there was no stir of life, nothing going on.  5 The road was mainly a winding path with hoof-prints in it, and now and then a faint trace of wheels on either side in the grass—wheels that apparently had a tire as broad as one's hand.

6 Presently a fair slip of a girl, about ten years old, with a cataract of golden hair streaming down over her shoulders, came along. … 7 The circus man paid no attention to her; didn't even seem to see her.  8 And she—she was no more startled at his fantastic make-up than if she was used to his like every day of her life. 9 She was going by as indifferently as she might have gone by a couple of cows; but when she happened to notice me, then there was a change! 10 Up went her hands, and she was turned to stone; her mouth dropped open, her eyes stared wide and timorously, she was the picture of astonished curiosity touched with fear. 11 And there she stood gazing, in a sort of stupefied fascination, till we turned a corner of the wood and were lost to her view. 12 That she should be startled at me instead of at the other man, was too many for me; I couldn't make head or tail of it.