Why Does Earth Have A Magnetic Field?

There is very little knowledge about why Earth has a magnetic field. There are strong theories suggesting that because the liquid metal circulates within the core of the earth, where there is a magnetic field, it produces electricity ‚ moving charged particles. These charged particles are the cause of a stronger magnetic field, strengthening the original field, in a chain reaction sort of mechanism; this continues happening until the field reaches the level of the magnetic field of the outer core and using its electrical conductivity, giving Earth a very strong magnetic field. The field is constantly changing, and even the poles move around because of this. Scientists have confirmed this creation and strengthening of magnetic fields with tests on liquid metals in laboratories.

The issue arises when trying to discover the source of the original field, which started the chain reaction in the first place. Because it is a continuous process, the original field does not have to be still happening. Theories have suggested that the first field could have been from the Sun itself, which could have been strong enough to start the chain when the Earth was still very young.

Another concept is that this is not a perpetual motion device. It cannot keep itself going; the liquid metals have to be kept liquid, which requires a certain amount of heat. As the Earth continues to cool down inside (over lots and lots of time ‚ it has been happening since the Earth was made in the first place), the liquid metals will begin to solidify. Once there is not enough movement to keep the field being strengthened and maintained, the field will die ‚ it will cease to exist. This probably won’t matter for us as the human race, as the Sun would have expanded to a red giant star, and engulfed the planet anyways.