The core of the earth is the name given to the central and innermost sphere of planet earth. Among its fundamental components we find nickel and iron, in a higher proportion and in less quantity with oxygen and sulfur.
The radius that it has is approximately 3,500 kilometers, a magnitude that is greater than that of the planet Mars and its internal pressure is millions of times more important than that of the earth's surface. Its temperature is really very high and can reach 6700 °, it is even hotter than the surface that the sun itself presents, while it is considered that this has to do with the heat that resulted from the collision of the particles when the earth was conformed.
Its outer core is liquid and is made up of iron, nickel and other less dense components, while the inner core is solid and also has iron, approximately 70% and 30% nickel, and then other heavy metals appear. like titanium, iridium and lead.
The core of the earth formed together with it about five billion years ago after a supernova explosion. The leftover heavy metals agglomerated into a disk, spinning around the sun. The core composed mostly of iron and other radioactive elements such as uranium and plutonium released heat and then by action of gravity the heavier materials sank in the center and the lighter materials floated to the crust. Such a process is known as planetary differentiation. And for this fact is that the core of the earth is composed of iron, nickel, iridium, among others, which are as we already said heavy materials.
It should be noted that when our planet was burning, the metals that today make up its nucleus suffered an alloy that became a very dense and strong structure, and for example, planet earth is the densest in our system.