Abstract The relevance of magnetic dipole and quadrupole strength distributions for the physics of a type II supernova are discussed. A recently developed high-resolution, large solid-angle system for the detection of 180° electron scattering at the superconducting Darmstadt electron linear accelerator (S-DALINAC) is introduced which represents a unique tool for the study of low-multipolarity magnetic transitions. First results discussed include the modification of the M1 strength in complex nuclei by meson exchange currents, the overall quenching of M2 strength and possible tests of in-medium vector meson scaling (Brown-Rho scaling) by selected magnetic form factors.