Earth and Milky Way. Computer artwork of the Earth seen from space, centred on Europe. The Northern Polar Region (white, at top) is illuminated by the Sun, indicating it is a Summer's day in Europe. Earth is the third planet from the Sun, and is thought to be the only planet in the solar system that supports life. It has an atmosphere of nitrogen and oxygen and clouds (white) of water vapour. Oceans of water (blue) form ice (white) at the poles. Land colours vary from green vegetation to barren brown land such as deserts. The bright band of the Milky Way is seen in the background.