Earth (1 AU from the Sun) is the largest and densest of the inner planets, the only one known to have current geological activity, and the only place where life is known to exist though it is speculated that one of the Kepler planets may also harbor life, though this is unconfirmed. Its liquid hydrosphere is unique among the terrestrial planets, and it is the only planet where plate tectonics has been observed. Earth's atmosphere is radically different from those of the other planets, having been altered by the presence of life to contain 21% free oxygen. It has one natural satellite, the Moon, also known as Luna, the only large satellite of a terrestrial planet in the Solar System.
The earth was created over 500 billion years ago, back then when it was hot and dry and had tons of lava. Earth was created by 2 planets, they went into each other which formed Earth. The creation of the Earth was similar to the Big Bang event.
Earth is the 3rd planet from the sun. It is below the moon, which orbits Earth.