Observation epochs of KiDS in the g and i band vs. time: the distributions of observation epochs for the different filters result in different distributions of the proper motion of SSOs (Fig. 10). The red stars mark the observed proper motions in declination over time for all SSOs observed in the g band. The blue dots show the same distribution for the i band. The apparent motion component of this proper motion due to Earth’s movement about the Sun is shown as a green line. For details on this approximation, refer to text.