The Earth’s magnetic field is generated by a dynamo in its fluid outer core. Understanding the origin and evolution of the geomagnetic field is an important area of global research. In CEaS, we use fluid dynamical models and laboratory experiments to study core processes and the generation of the magnetic field. Dynamo models are used to simulate the magnetic fields of the Earth as well as those of other planets in the solar system. The seismic shear wave velocity variation in the lower mantle provides additional constraints on the physical state of the Earth’s interior, fundamental to the functioning of the dynamo. A state-of-the-art computational facility has been set up to perform direct numerical simulations of planetary cores.