dynamo theory

Dynamo theory explains how celestial bodies like Earth generate their magnetic fields through the movement of conductive materials, such as molten iron in Earth's outer core. As these fluids flow, they create electric currents, which in turn produce magnetic fields. The combined and self-sustaining interactions of these currents and magnetic fields, reinforced by planetary rotation and convective motion, maintain the magnetic field over long periods. Essentially, it's like a natural electrical generator within planets, converting the movement of liquid metal into a magnetic shield that protects the planet from solar and cosmic radiation.