Planet

A Planet (planets), Is a large imperefct sphere capable or supporting life, water, heat, or certain toxic gasses. There are two different types of classifications of planets, Terrestrial (capable of sustaining life) or Gas gaint (only containing gases). The only known terrestrial planets in the Sol System are Venus, Mercury (thin on/ off atmosphere), Earth and Mars. There have been rumors that if algee or plant life were to be placed on Mars, centuries later the planet could support life. NASA is currently exploring options of trying to tap into Mars's North Pole which contains water, as well as Jupiter's Moon Titan, capable of also hosing water, so far no attemps have been made. Venus is rulled out althogether, as being habitable since it contains an unastable surface full of active volcanoes, toxic greenhouse gaxes, sulfric acid rain storms, too little oxgyen and an atmosphere full of CO2. Mercury cannot be colonized in any way since it is too close to the suns (Sol's) rays and has no stable atmosphere. So far humans must remain on Earth or find another planet out of their solar system to colonize. The Gas giant planets in the Sol System are Jupiter, Saturn and Uranus, all those planets mentioned also attract giant asteroids that would cause harm to its inner neighbors, Mercury, Venus, Earth and Mars. In DC Comics Earth serves as a planet for many superheroes and villains, including the greatest superhero of all Superman. And in Marvel Comics Earth serves as a planet for many superheroes and villains as well. In both comics, many intergalactic and galactic aliens or natives have tried to conquer Earth with little, short or no success.

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Planet article on Wikipedia