2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/123197A new general procedure to construct realistic spacetimes is introduced. It is based on the null congruence on a time-oriented Lorentzian manifold associated to a certain timelike vector field. As an application, new examples of stably causal Petrov type D spacetimes which obey the timelike convergence condition and which admit an isometric spacelike circle action are obtained.18 pagesGeneral Relativity and Quantum Cosmologytext