The earth's core consists of a fixed inner part and a liquid outer part. The core determines the magnetic field and therefore life. But how does that core get there?
The prevailing views
Through seismic data, chemical theories and measurements of the earth's magnetic field, researchers know that the core makes up about half the diameter of the earth and consists mainly of iron and nickel. They also know that the core has a solid inner part and a liquid outer part. The outer core probably provides the magnetic field.
So far, the researchers thought the nucleus was so large because the earth collided with another planet in its younger years. The planets may have had a similar composition and chemistry, but the matter was not evenly distributed in the collision, and instead of flying back into space, the iron core of the other planet sank into the earth. Researchers can now accurately analyze the distribution of isotopes and rocks, and now there appear to be such large differences in chemistry that the theory is very questionable.
The core was presumably liquid initially, but as the temperature dropped, the iron inside crystallized and became a solid inner core that is still growing. Researchers have recently discovered that the core melts in the west and solidifies in the east and is therefore much more dynamic than expected.
How does science progress?
Future satellite missions can probably provide more and better data about the outer core. Satellites constantly measure the magnetic field. In this way, they can register changes and find out which processes are taking place at the core, and how quickly they take place.
Why is it important?
In the past, the magnetic field fluctuated strongly and the poles often changed places. It is important to know how often and why this happens, because without a magnetic field we would be exposed to too much harmful radiation from space.
What is the chance of answers?
Although better satellites, computers and seismographs bring us closer to an answer, we never know for sure what is inside the earth.
Elements created layers of earth The earth was layered by a process called differentiation, in which the elements are separated on the basis of, among other things, density. Most heavy substances and the substances that connect to heavier substances fell to the core; the lighter fabrics entered the mantle.
Lithophilic elements are light and connect with silicon. They are in the mantle and the crust.
Siderophilic elements are heavy and form a connection with iron. They are at the core.
Chalcophilic elements react with sulfur. They are mainly in the core.