  In this work we consider the effect that the appearance of pseudoscalar
condensates in a neutron star can have on its cooling rate. We make no
particular assumption on the origin and characteristics of these possible
condensates and only assume that in regions where the pseudoscalar density
varies the propagation of photons is governed by modified Maxwell-Chern-Simons
electrodynamics. We find that this gives non-trivial reflection coefficients
between regions of different pseudoscalar density and may affect very
substantially the star cooling rate. While quantitative results do depend on
precise details that can only be answered once a proper equation of state is
determined, the general trend is quite universal and serious consideration
should be given to this possibility.
