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arXiv · 2606.00612

The Mass, Orbit and Location of Planet Nine Derived from Classical Astrophysics

Abstract

Our models are based on the planet's presumed influence on the orbits of 12 TNOs: the original 6 analyzed by the CalTech astronomers and an additional 6 selected by the authors using similar although broader criteria. An additional goal of our approach is to make the rationale behind each claim regarding Planet X mathematically visible and verifiable to readers, who can use the models for further analysis with their own TNO data sets should they choose, which is rarely an option with simulations. Using the math models described herein we found that each orbit of the 12 asteroids (12As) lies close to the same plane, presumably the planet's orbital plane. This geometric near-symmetry was found to uniquely determine the planet's orbital elements longitude of the ascending node at +107.7 degree and inclination of +19.5 degree. The planet's argument of perihelion is 307.5 degree. The planet's off axis Lagrange points L4 and L5 were found to play a key role in producing this cluster. At least 4 and possibly 5 of the 12As appear to be in mean motion resonance with the planet, which led to an estimate of the orbit's semi major axis length of a 510 AU and a period of 11512 years. The eccentricity for the planet is 0.39 implying a perihelion of 311 AU. The estimation for the planet's location looks like this: the first two locations estimated to be in the lower region of Taurus, the latter in the upper region of Libra. A wide orbital ellipse that completely surrounds half the asteroids' orbits nearest to their perihelia. The estimated planet's mass is 7.1 Earth masses.

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Mattia Galiazzo, Robert Finch. 2026-05-30. The Mass, Orbit and Location of Planet Nine Derived from Classical Astrophysics. https://arxiv.org/abs/2606.00612

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