Earth- and Planetary Magnetism
Shown is the magnetic field generated in the fluid metallic core of planet Earth. The magnetic field lines leave the Earth at the South Pole and re-enter at the North Pole. Numerical simulations show the movements of the poles – including total reversals by 180° - as also documented in Earth's history.
Magnetic field and geo-dynamo
Temperature differences in the Earth's interior cause movements of the hot liquid iron in the outer core. Without the Earth's rotation, these movements would be random. The rotation, however, organizes the movements into helical structures parallel to the rotational axis. A giant, planetary-scale dynamo is created – the geo-dynamo! Just as electric currents in a wire generate a magnetic field, the electric currents within the liquid iron core generate the Earth's magnetic field that protects us from harmful radiation from space.
Our group studies how the magnetic field is generated in the Earth and other planets. It measures the Earth's magnetic field and how it has changed in the past. The Earth's magnetic field forms a vital protection from cosmic rays.