Hyades member selection in Galactic Cartesian XY coordinates (i.e., top-down view on the Galactic plane). The data and colors are the same as in Fig. 1. We also overplot ellipses (3-σ level computed from the covariance matrix) on the sources as determined for increasing distances to the cluster center (marked as a black cross). Top panel: position angle of these ellipses as a function of the distance to the center. Main panel: approximate contour of the Hyades tidal tails as given in Chumak et al. (2005).