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arXiv · 2110.11745

A survey on Hungaria asteroids involved in mean motion resonances with Mars

Abstract

Context. A region at the inner edge of the main asteroid belt is populated by the Hungaria asteroids. Among these objects, the Hungaria family is formed as the result of a catastrophic disruption of (434) Hungaria asteroid hundred million years ago. Due to the Yarkovsky effect, the fragments depending on their direction of rotation are slowly drifting inward or outward from the actual place of collision. Due to this slow drift these bodies could approach the locations of the various mean-motion resonances (MMRs) of outer type with Mars. Aims. We aim to study the actual dynamical structure of Hungaria asteroids that is primarily shaped by various MMRs of outer type with Mars. Moreover, we also seek connections between the orbital characteristics of Hungaria asteroids and their absolute magnitude. Methods. To map the resonant structure and dynamics of asteroids belonging to the Hungaria group, we use the method FAIR (as FAst Identification of mean motion Resonances), which can detect MMRs without the a priori knowledge of the critical argument. We also compile stability maps of the regions around the MMRs by using the maximal variations in the asteroids' eccentricities, semi-major axes, and inclinations. We numerically integrate the orbits of all asteroids belonging to the Hungaria group available in the JPL Horizon database together with the Solar System planets for one and ten million years. Results. Having studied the resonant structure of the Hungaria group, we find that several asteroids are involved in various MMRs with Mars. We identify both short and long-term MMRs. Besides, we also find a relationship between the absolute magnitude of asteroids and the MMR in which they are involved.

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E. Forgács-Dajka, Zs. Sándor, J. Sztakovics. 2021-10-22. A survey on Hungaria asteroids involved in mean motion resonances with Mars. https://doi.org/10.1051/0004-6361%2F202141719

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