Posterior polarization results. The radial coordinate represents polarization degree and the angular coordinate the polarization angle. The polarization angle here is transformed to equatorial coordinates. The contours are for the 30th, 60th, and 90th percentiles of the credible regions. The plots are reflected about the periodic boundary of 180° for visual clarity. For the last three time intervals, we do not display contours and instead show the posterior samples as the parameters are poorly identified. The arrows that point from the last to the current position are meant as visual guides only.