Evolution of the relative mean longitude with respect to Earth, λ_r, of 2023 FY₃. The figure shows results for the nominal solution (in black) as described by the orbit determination in Table 1 and those of control orbits or clones with Cartesian state vectors (see Appendix A) separated +3σ (in green), −3σ (in light green), +6σ (in blue), −6σ (in cyan), +9σ (in red), and −9σ (in pink) from the nominal values in Table A.1. The time interval (−200, 100 yr) is shown. The output cadence is 4.383 h.