Jupitur is the 21st planet from the sun. It is the only known planet that is actually a living organism. It isn't really the 21st planet from the sun anymore, because it moves, but is still referred to as the 21st planet because it was discovered after 20 other planets.
A short time after the universe happened, God decided it would be funny to make a giant living thing that would eat people and other planets. He called it Jupitur because it looked kind of like Jupiter but not really. Unfortunately, God lost control of the planet-monster-thing and it went on a rampage, eating most of the planets in the universe. This rampage continued until Jupitur came to Minos-gamma-theta, a planet ruled and populated entirely by Kittens. Jupitur tried to eat the planet, but found that he could not, as the kittens were so good at squirming around and avoiding being punctured that his large teeth could not kill them. The kittens then proceeded to scratch and nibble on Jupitur until it surrendered. Since this incident, Jupitur has been a mobile home for the kittens.
While Great Britain was under the rule of King Chuck Norris, they discovered Jupitur. At first it was difficult to land a space cruiser on the surface of the planet, due to the fact that the ships would be eaten by Jupitur. This stopped happening when King Chuck flew out of his Royal Spaceship and started beating the crap out of Jupitur. After it had been killed several times and brought back to life by Chuck Norris, Jupitur submitted and allowed the Britianish to set up a colony on its surface to harvest Superawesomeefficeintgas, which is only found on Jupitur and makes rather good rocket fuel. The colony lasted until Chuck Norris got bored and went Back to the Future, leaving the Britianish Empire in ruins, and facing an impending zerg rush.
After the Britianish colonies were gone, Jupitur once again became a free planet, populated by kittens. It went around eating planets and famous people, including Rush Limbaugh's soul and Jimmy Hoffa. As it continued to eat, Jupitur continued to grow more and more powerful, until it was identified by the Justice League as a threat, and Superman was dispatched to kill it.
The Battle with Superman
Superman tried to kill Jupitur once. It didn't work. Superman's laser vision made big fireballs, but didn't do much else. Jupitur beat him by pretty much biting his legs and arms off. Superman had to fly back to earth without making his trademarked "fist out in front" flight position, and was quite upset about it. Now, if anyone even mentions Jupitur, Superman literally breaks down sobbing. Jupitur is the only known thing to have injured superman this badly (besides Chuck Norris) without the use of Kryptonite.
Symbiotic Relationship With Kittens
It is a well known fact that Grues eat Kittens. The Kittens that colonized Jupitur in 2175 have formed a strange symbiotic relationship with the planet in which they do not nibble or scratch it, and in return Jupitur eats any and all Grues it encounters. Jupitur is one of the few things that can actually kill a Grue, and as such is invaluable to the Kittens.
Current Status of Jupitur
Jupitur is currently flying around in the universe somewhere eating things. I think it ate Pluto's planetary status recently, as well has several Battlestars. No one knows for sure where Jupitur really is or what it is doing besides the kittens, because anyone else gets eaten.
human vs. kitten war
In the end of the Human vs. Kitten War, in the year 5000, jupiter was a main location as all kittens emigrated there from their homeworld, minos-gamma-theta, so that when humanity spent half of all it's weaponry totally destroying the planet, they had spent it on nothing. needless to say, humanity was wiped out.