Earth is quite large, and of course there is much more than what we can see on the surface. In fact, if we could cut the Earth in half we would see that it has multiple layers. However, the interior of our planet still holds some mysteries. Although astronauts explore other orbiting planets and satellites, the inner recesses of the Earth are still out of reach.
Advances in seismology have allowed us to learn a great deal about the Earth and the layers that make it up. Each layer has different properties, compositions and characteristics that affect key processes on our planet. From the outside to the inside, the order of the layers is as follows: crust, mantle, outer core, and inner core.
Also, like all terrestrial planets, the interior of the Earth consists of layers. This means that when one layer is removed, another is found, which differs from the previous one due to its chemical and geological properties as well as its temperature and pressure.
Layers of the Earth
The Earth can be divided in two ways: mechanically (or rheologically) and chemically. Mechanically (that is, according to the study of liquids) it can be divided into lithosphere, asthenosphere, mesospheric mantle, outer core and inner core. Instead, it is chemically divided into crust, mantle (which can also be subdivided into upper and inner), and outer and central core.
The inner core is solid, while the outer core is liquid and the mantle is solid. This is due to the relative melting points of the different layers as well as the increase in temperature and pressure as you go deeper into the layers. Furthermore, the difference between these layers is due to processes that took place during the early stages of the Earth’s formation (4.5 billion years ago).
According to the scientists, the fusion could have caused the densest substances to sink towards the center, while the less dense materials remained in the crust. For this reason, the core is believed to be composed primarily of iron, nickel, and various light elements.





