Classical celestial mechanics calculates planetary orbital precession via gravitational perturbations between planets, yet it cannot fully explain the residual perihelion shift of Mercury at 43.03 arcseconds per century. General relativity attributes this residual deviation to spacetime curvature and achieves numerical matching through geometric fitting with Riemannian metric tensors. However, this model has fundamental physical flaws: gravity is a unidirectional attractive field without the vector cancellation properties seen in vortex or electromagnetic fields. Geometric fitting is merely a pure mathematical approximation and cannot represent the true interaction mechanism of the universe. Based on the real cosmic motion state of the Solar System, this paper establishes a unified dynamic mechanism combining overall galactic orbital drag, medium phase hysteresis and differentiated planetary orbital self-correction. The Sun is not a stationary reference frame; it continuously carries the complete heliospheric medium bubble and all planets to orbit the Milky Way spiral arms at high speed. The spiral arms of the Milky Way follow a density-wave hysteresis structure. The medium composed of interstellar matter, solar-derived photons and plasma lacks rigid-body synchronous characteristics. As the system moves forward, asymmetric medium density distribution in the front and rear, delayed force transmission and continuous orbital drag perturbations inevitably arise. This effect acts on all planets of the Solar System rather than only Mercury. Observed data confirm that Venus, Earth, Mars and outer planets all exhibit measurable residual orbital precession deviations, though their magnitudes are far smaller than Mercury’s: approximately 8.6 arcseconds per century for Venus and 3.8 arcseconds per century for Earth. Solar gravity provides a natural balance mechanism for orbital correction, yet the correction effect has an upper load limit. Outer planets orbit far from the Sun, where perturbations induced by medium drag are inherently weak. Solar gravity possesses sufficient orbital space and acting duration to repair most deviations, leaving only tiny residual offsets. Mercury orbits extremely close to the Sun’s core region, where the medium density is extremely high and drag perturbation intensity greatly exceeds the upper limit of gravitational correction capacity. Excess orbital deviations cannot be fully repaired and accumulate year after year, forming the prominent observable anomalous precession of 43 arcseconds per century. This mechanism possesses universal applicability across all galactic scales. It requires no fictitious physical hypotheses such as spacetime curvature or dark matter, with clear and complete objective dynamic causality. It can entirely replace general relativity to explain the residual perihelion precession of all planets in the Solar System.
Jiaqing Yan (Sun,) studied this question.