Planet Earth was formed over four and a half billion years ago, from a great cloud of gas, rock and dust, that was orbiting around a new star, the Sun. Its atmosphere was created by the release of water and gas vapors from early volcanic activity. Due to the radioactive metals deep within its central core, it is constantly evolving and changing its exterior make up.

Earth's surface is 70 per cent covered with salt water oceans, with the remainder consisting of its continents and islands. Its oceans have been alive for at least three and a half billion years, which were created over time by rogue comets smashing into our planets exterior surface.

Earth's interior structure is also extremely unique; the continents are sort of replicated, and point toward Earth's centre. Imagine a mirror image of Earth's outer landscape, pointing inward underneath our outer crust, and you have the picture. Earth's thin crust consists of six large plates, which move around and shift the continents they carry. Its crust is about 25 kilometers deep, which is very thin in comparison to the Earth's size.

Earth's core is similar in size to the Moon, and is made up of mainly iron and nickel. Its inner temperature is also about as hot as the Sun, which produces the heat which travels to the surface, through the rising hot currents of molten rock. It is these currents which influence the movement of the 'plates', which in effect changes the shape of Earth's surface. Over hundreds of millions of years, the continents have formed and been broken up, as the surface of our planet continually reshaped itself.

Earth's orbit remains in a safe zone for life as we know it to continue. In earlier days, it could have been a stray in orbit which effected the ice ages. Too far from the Sun, and our planet would simply freeze over. Too close to the Sun of course, would mean that we would boil and fry up. Lucky for us, our planet orbits perfectly at the moment, and Earth's magnetic field is its only protection from the unforgiving solar winds.