Earth--Moon--Venus as a Resonance-Cluster Hypothesis in USP Field Theory: Co-Formation, Disk-Phase Capture, and Mercury as a Possible Orbital Fossil

This document presents a speculative but falsifiable USP Field Theory hypothesis for several inner-solar-system features: the close isotopic similarity of Earth and Moon, the unusual orbital eccentricity and inclination of Mercury, and the slow retrograde rotation and missing large satellite of Venus. The proposed interpretation is that Earth, Moon, and Venus may have originated as a resonance-compatible planetary cluster, later integrated into the forming solar basin during the disk phase. In this scenario, disk-phase gas drag, orbital damping, and angular-momentum redistribution allowed the cluster to separate into the present inner-solar-system architecture, while Mercury retained an excited eccentric and inclined orbital state as a possible resonance fossil. This work does not replace standard solar-system formation theory, N-body orbital mechanics, geochemistry, isotope analysis, or secular perturbation theory. Instead, it provides a USP-language hypothesis layer with operational proxies, capture-energy constraints, a Mercury orbital-mismatch index, a Venus angular-momentum residue interpretation, and predeclared falsification criteria. The paper includes explicit non-claims, hard constraints, a simulation roadmap using N-body plus gas-drag modeling, and test pathways involving Mercury orbital residuals, future Venus isotope measurements, and Earth-crossing asteroid isotope populations. The purpose is to make the hypothesis testable and rejectable, not to present it as established planetary history.