and ruffini@icra.it A globally neutral system of stellar dimensions consisting of degenerate neutrons, protons and electrons in beta equilibrium is considered using the ultra-relativistic solution of the Thomas-Fermi equation. Such a system at nuclear density having mass numbers A ≈ 10 57 can exhibit a charge distribution different from zero. The analysis to investigate the magnetic field induced by the rotation of the system as a whole rigid body and its stability is presented in the framework of classical electrodynamics.