2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/204410There are conflicting statements in the literature about the gravitational Faraday rotation of the plane of polarization of polarized electromagnetic radiation travelling through a gravitational wave. This issue is reconsidered using a simple formalism describing the rotation of the plane of polarization in a gravitational field, in the geometric optics approximation. It is shown that, to first order in the gravitational wave amplitude, the rotation angle is a boundary effect which vanishes for localized (astrophysically generated) gravitational waves and is non-zero, but nevertheless negligible, for cosmological gravitational waves.11 pages, latex, to appear in New AstronomyAstrophysicsGeneral Relativity and Quantum Cosmologytext