Formation of the Solar System
A solar system refers to a star and all the objects that travel in orbit around it. Our solar system consists of the sun - our star - eight planets and their natural satellites (such as our moon); dwarf planets; asteroids and comets. Our solar system is located in an outward spiral of the Milky Way galaxy.
To fully understand Earth and the processes that shape our planet we must first look to the heavens to the formation of our solar system and therefore Earth.
There are two main theories of how the solar system formed:
An evolutionary approach; in other words the planets formed from a spinning cloud, condensing out into planets via gravity.
The solar system formed from a one-off never to be repeated event.
Image courtesy of NASA WMAP Science Team