SHIELD

The magnetic field of the Earth spreads from the internal core 

of up to his confluence with a current of particles of high energy 

that comes from the Sun, the so called solar wind. 

 

It is generated by the movement of the alloys of cast iron 

in the external core of the Earth. It protects us from the harmful 

ultraviolet radiation and the cosmic beams.

To illustrate the idea of magnetic field, the most exact image
is obtained by compasses that locate the true north of the Earth
and indicate the direction of the lines of the field.