Upper panel: results of the numerical solutions of the full equations of motion (heliocentric distance r plotted against time) for the nanodust particles with Q/m = 10⁻⁴ e/m_p emitted at 0.03 AU from a parent body moving in a circular Keplerian orbit of 5° inclination at the point of maximum latitude. The solutions correspond to three different models: no corotation (solid line), maximum corotation (dotted), and the critical point model based on Weber & Davis (1967; dashed line). The lower panel shows the potential function U(r) and the conserved quantity E plotted against r for the same assumptions about corotation.