Count the planets in the solar system and make an assessment of their various sizes and distances from Sol and the Earth as you leave on your journey to the beginning of the universe. You'll find that the line between planet and smaller planetoids, like asteroids and meteorites, has yet to be firmly set in place in the astronomy books, and in the universe.
 
We were all taught during our school indoctrination of nine planets circling Sol at varying distances. Mercury and Venus lie closest to Sol, with the Earth, Mars, Jupiter, and Saturn residing at greater distances from Sol, while Uranus, Neptune, and disputed Pluto orbit at the greatest distance on average as compared to the other planets. Millions of school and reference books, thousands of articles, and countless periodicals also include references to Pluto being officially recognized as the ninth planet in the solar system. The publishers of these publications will be calling for a rewrite of all of this material and the history books will have to be changed, if some astronomers and space scientists have their way.

Planet X came spinning into the view of Caltech astronomer Michael Brown on July 29, 2005, and changed the way astronomers and star gazers think about Pluto, and the definition of a planet. An icy, Kuiper Belt resident Michael named after Xena the warrior goddess of the famed television series, at least until the International Astronomical Union speaks on this matter, Planet x orbits Sol at a distance nearly twice as great as Pluto's. Planet X's 560-year orbit is also inclined to the ecliptic by nearly twice as much as Pluto's, which results in Planet X being closer to Sol than Pluto during its orbit, at times.
 

The largest Kuiper Belt objects compared

How much bigger is Planet X than Pluto? Astronomers have measured the brightness and distance of Planet X from Sol, as compared to objects of known brightness in the solar system. Based on their data and calculations, astronomers believe Planet X to be bigger than Pluto, but just how much bigger has yet to be firmly etched in stone by the various astronomical societies and agencies tasked with determining if Planet X is indeed bigger than Pluto and by how much. This fuzzy-news has pushed Pluto into tenth place in the nine planet race in the solar system and into second place in the size ranking of the objects in the Kuiper Belt and astronomers, and star gazers have only searched a small percentage of the Kuiper Belt for objects bigger than Pluto.

Will bigger objects than Planet X be discovered in the Kuiper Belt or somewhere on the outer fringes of the solar system? The first Kuiper Belt objects were viewed by star gazers and astronomers in the early 1990s, but since this time larger and larger objects have been located in the Kuiper Belt. In 2002, an object half the size of Pluto was discovered floating in the Kuiper Belt, which astronomers named Quaoar. Just two years later, 2004DW and Sedna were discovered, each respectively two-thirds and three-quarters the size of Pluto. It wouldn't be surprising, therefore, if star gazers and astronomers were to find an even larger object floating in the Kuiper Belt, than Planet X at some point in the human journey to the beginning of the universe..

Hubble has given us our best views of Pluto, so far. This photo shows Charon as well.

 

Compare the various sizes of the planets as you pass by
A distance object at best, Pluto looks quiet and serene here. NASA photo.