The surface of the Earth, the crust, makes up a very small part of the whole planet. While it is relatively straightforward to find out about the Earth’s surface, investigating deep within the Earth is part science, part guesswork. What is known is that there are three main layers: the crust, the mantle and the core, and that these consist of rocks and metals in various states and forms.
The Earth started out as a ball of very, very hot liquid. This liquid was mostly made of two elements called oxygen and silica. But there were small amounts of other elements too. In fact, it was a mixture of almost every element in existence. This all happened around 4.6 billion years ago – that’s a really long time, so long that we can’t even imagine it.
Over time, Earth began to cool down. The heavier elements, like iron and nickel, sank into the centre of the planet (the core). And it’s hot: the Earth’s core is as hot as the surface of the sun, so hot that we wouldn’t be able to go near it, let alone touch it. But you don’t have to worry about getting too close. Wherever you are, whether in Kenya, China or Brazil, the core is around 1800 miles below your feet. This means we will never be able to visit it.
Even though we can’t actually go to the Earth’s core, we know some things about it. We know, for example, that the core is full of iron, because Earth acts like a giant magnet, drawing some elements to it. This magnetic core is very useful: it means we can use a compass to find our way, like sailors in the ocean.
Picture Credit : Google