The Astrodynamics Primer on Cislunar and Translunar Space
The Earth-Moon environment is multiscale and strongly nonuniform, yet it is often discussed as a single cislunar regime. In reality, circumterrestrial space is partitioned by changes in perturbation hierarchy, by gateway topology, and secular and resonant structures that differ qualitatively across the domain. This paper develops a unified spatiographic description of that structure, combining perturbative theory, semi-analytical resonance cartography, restricted multi-body dynamics, and direct numerical mapping. The terrestrial-cislunar transition is sharpened through the Laplace radius, beyond which lunisolar torques overtake the classical oblateness-dominated picture. Earthward of the Moon, cislunar space divides into a secularly dominated inner zone and an outer zone structured by interior lunar mean-motion resonances. Near the Moon, circumlunar space forms a distinct dynamical enclave organized by the EM gateway geometry and the lunar SOI. Beyond the Moon, translunar space forms an outer circumterrestrial province in which the Moon acts as an interior perturber, the Sun remains an exterior perturber, and the resulting dynamics acquire a mixed lunisolar secular and resonant architecture before weakening outward toward heliocentric behavior. These results are synthesized through MEGNO and fate-class cartographies across six numerical map domains. The maps reveal where quasiperiodic confinement survives, where resonance overlap and gateway transport produce sticky residence and organized escape, and where solar forcing becomes a qualitative architectural ingredient. Placed alongside a curated catalog of satellites and debris, the framework provides a dynamical geography of this environments that clarifies the transitions among cislunar, circumlunar, and translunar motion and offers a more precise basis for interpreting stability, transport, and long-term Earth-bound behavior.