Abstract
<jats:p>This study aims to test and validate a highly specific gravitational model of Planet 9 in the outer Solar System. Through rigorous N-body supercomputing simulations (utilizing the REBOUND IAS15 Integrator) over timescales ranging from 20 to 50 million years, we demonstrate that a Planet 9 model with a mass of 12.5M⊕ and a semi-major axis of 806.0 AU successfully shepherds the most chaotic and enigmatic Extreme Trans-Neptunian Objects (ETNOs). The simulation of three distinct orbital regimes—2017 OF201 (outer edge), 90377 Sedna (detached), and 2023 KQ14 (inner edge)—reveals a universal shepherding mechanism. Planet 9 prevents ejection by actively lifting the perihelia of these ETNOs and locking them into stable secular resonances, confirming this profile as a mathematically verified reality rather than a mere hypothesis. Crucially, this profile firmly departs from recent canonical models that favor a closer, lower-mass Planet 9. After 23 previous rigorous parameter sweeps resulted in the consistent ejection of these specific ETNOs, this 24th iteration stands as the first demonstrated parameter set in the literature capable of simultaneously shielding 2017 OF201, Sedna, and 2023 KQ14 from fatal scattering.</jats:p>