We test a geometric prediction derived from a physical hypothesis—that counter-propagating solar and lunar re-radiated photon streams may produce a localized deflection field in the space on both sides of the Moon—which yields four specific, testable geometric constraints: systematic radial acceleration residuals should appear in a specific spatial-angular-phase window (1–5 lunar radii, 10–45 degree Sun–Earth angle, full moon period, symmetric on both sides of the Moon). Using publicly available precision orbit determination data from the Lunar Reconnaissance Orbiter (LRO), the ARTEMIS probes, and published Chang'e series VLBI residual statistics, we identify a persistent residual signal within this predefined window. The measured peak radial perturbation amplitude is 3. 2 +/- 0. 8 mm/s². Standard lunar gravity models and classical perturbative forces, assessed component by component, do not appear to fully account for this signal, though a complete quantitative error budget remains to be performed. We do not claim definitive detection of a new force field. Given the limitations of the available data—including the reliance on published statistical summaries rather than raw tracking data for the Chang'e missions—we identify this signal as a testable target for future lunar missions equipped with dedicated instrumentation. All data used in this study are publicly accessible, and the analysis methods are fully documented to enable independent verification or falsification.
Menggang Yu (Tue,) studied this question.