Our research is focused on analytical calculations of orbits of particles and light in general relativistic spacetimes. As a main application we study problems in astronomy, but we also investigate relativistic effects on the motion and tracking of satellites and the rate of clocks which includes applications to relativistic geodesy. Furthermore, we study fundamental problems in electrodynamics (including nonlinear and higher-order electrodynamics) and in alternative theories of gravity such as Finsler geometry. Our interest in fundamental and mathematical aspects of gravitation and electrodynamics brings us in close contact to the research group Gravitation and Quantum Theory.