Resonance and Intersection with the Earth for Dust Particles Ejected from Asteroid Ryugu

Abstract

The orbital dynamics of dust particles ejected from the surface of 162173 Ryugu and escaping into interplanetary space within 1 000 years, mean motion resonance of dust particles with Earth and close encounters between dust particles and Earth were analyzed using direct numerical simulations. The effects of non-gravitational perturbations (solar radiation pressure, Poynting-Robertson drag and solar wind drag) on the long-term orbital evolution of dust particles were investigated. In the spatial region where dust particles move, the evolution of the semi-major axis, eccentricity and orbital inclination of the dust particles in the 3:4 and 4:5 mean motion resonances with the Earth were analyzed. That is, the semi-major axis of the dust particles showed periodic oscillations, the eccentricity showed periodic changes and slightly increased, and the orbital inclination showed a periodic downward trend. The number of close encounters between dust particles and the Earth was counted and analyzed. It is found that the number of close encounters reaches a maximum value within a period of 400 to 500 years, and the dust particles will not collide with the Earth within 1 000 years.

Keywords

asteroid / orbital dynamics / dust particles / mean motion resonance