Results of the model fitting of the kinematics for knot C3. Within core separation r_n < 1.19 mas its inner trajectory follows the precessing common trajectory. In the upper left panel the red dashed line (modeling the entire trajectory) and the solid black line (modeling the inner trajectory) coincide within core separation r_n < 1.19 mas, showing the curvature in its outer trajectory. In the upper right panel two additional modeled trajectories (green and magneta lines) for ejection epoches t₀ ± 0.5 yr (or ϕ ± 0.61 rad) are also added, demonstrating that most of the observation data points are within the position angle range defined by the two additional modeled trajectories and the precession period is determined within an uncertainty of ~ ± 0.5 yr.