Mechanism of Planetary Orbital Precession (Second-Revised Final Version)

The 43-arc-second residual precession of Mercury’s perihelion per century has long been regarded as the core observational evidence for spacetime curvature in general relativity. A review of historical solar-system perturbation calculations and numerical simulations shows that this residual difference is not an inherent defect of the Newtonian gravitational system. The Le Verrier-Newcomb analytical theory adopts full-orbital-period time-averaging, which smooths out transient strong gravitational torques during close planetary encounters. Mainstream N-body numerical simulations in the 1980s employed a large fixed 5-day integration step, leading to severe under-sampling of short-duration strong gravitational pulses and producing an implicit numerical-averaging effect. Modern DE ephemerides directly embed post-Newtonian relativistic corrections at the underlying level and fit parameters against observational data, resulting in circular reasoning and making it difficult to obtain genuine perturbation results within the pure-Newtonian framework. From the perspective of geometric-physical intuition, genuine perihelion precession corresponds to azimuthal rotation of the empty focus of the ellipse, namely the overall positional shift and deflection of the entire elliptical orbit. Pure orbital deformation only changes the ellipticity of the orbit; the empty focus merely moves radially toward or away from the Sun without azimuthal re-orientation. Mercury possesses the largest orbital eccentricity among eight planets. Meanwhile its mass is far smaller than the Sun, Venus and Earth, so its orbit is highly susceptible to external gravitational perturbations, and its empty focus is far from the Sun and extremely sensitive to lateral torques. The actual pulling effect for precession concentrates within short-day windows of limited planetary close encounters over a century. Whether analytical outputs obtained by time-averaging correspond to real physical evolution cannot be judged by mathematical derivation alone. The genuine physical criterion must rely on long-term pure-Newtonian N-body integration without relativistic corrections, with adaptive step-size refinement activated during close-encounter intervals, so as to determine the true physical origin of the 43-arc-second residual.