Numerical integration frameworks play a pivotal role in validating long-term planetary defense architectures and mega-scale astroengineering scenarios, such as orbital migration trajectories. However, the high-fidelity validation of these computational models requires stress-testing against the most extreme physical boundaries. This paper presents a rigorous empirical calibration of the REBOUND n-body integration package utilizing the highly energetic, extreme retrograde hyperbolic trajectory of the interstellar object 3I/ATLAS (C/2025 N1). By coupling the numerical engine to a strict heliocentric reference framework and implementing the full three-dimensional non-gravitational force tensor formulated by Marsden, Sekanina, and Yeomans (1973), the initial barycentric coordinate shearing was entirely suppressed. Parametric optimization of the multiaxial outgassing coefficients converged within an absolute sub-meter threshold of 0.000049 km against NASA/JPL Horizons ephemerides. This verified computational environment was subsequently deployed to simulate a controlled macro-engineering scattering maneuver using 137 Meliboea as a payload reference. Assisted by a SciPy automated Nelder-Mead simplex routine, the trajectory achieved a perfect, non-demolition flyby corridor at 75.93 Earth radii. The multi-body tracking metrics confirmed a definitive heliocentric orbital expansion, precisely clamping the analytical migration target of 21.40 km of spatial displacement per synodic encounter while empirically proving the binary adiabatic coupling of the Earth-Moon system. These results establish that the integrated software core constitutes an unyielding, empirically locked laboratory fully qualified to model civilizational-scale planetary migration paths.
Moisés Frutos Plaza (Sun,) studied this question.