APOPHIS -- Effects of the 2029 Earth's Encounter on the Surface and Nearby Dynamics

Abstract

The 99942 Apophis close encounter with Earth in 2029 may provide information about asteroid's physical characteristics and measurements of Earth's effects on the asteroid surface. In this work, we analysed the surface and the nearby dynamics of Apophis. The possible effects of its 2029 encounter on the surface and environment vicinity are also analysed. We consider a 340 metres polyhedron with a uniform density (1.29 g$\cdot$cm${}^{-3}$, 2.2 g$\cdot$cm${}^{-3}$ and 3.5 g$\cdot$cm${}^{-3}$). The slope angles are computed, as well their variation that arises during the close approach. Such variation reaches 4${}^{\circ }$ when low densities are used in our simulations and reaches 2${}^{\circ }$ when the density is high. The zero-velocity curves, the equilibrium points, and their topological classification are obtained. We found four external equilibrium points and two of them are linearly stable. We also perform numerical simulations of bodies orbiting the asteroid, taking into account the irregular gravitational field of Apophis and two extra scenarios of perturbations: the solar radiation pressure and the Earth's perturbation during the close approach. The radiation pressure plays an important role in the vicinity of the asteroid, only cm-sized particles survived for the time of integration. For densities of 2.2 g$\cdot$cm${}^{-3}$ and 3.5 g$\cdot$cm${}^{-3}$, a region of 5 cm radius particles survived for 30 years of the simulation, and for 1.29 g$\cdot$cm${}^{-3}$, only particles with 15 cm of radius survived. The ejections and collisions are about 30-50 times larger when the close encounter effect is added, but around 56-59% of particles still survive the encounter.

17 pages, 15 figures

References in corpus (6)

• Orbits and Manifolds near the Equilibrium Points around a Rotating Asteroid
• Numerical predictions of surface effects during the 2029 close approach of asteroid 99942 Apophis
• Thermal Infrared Observations of Asteroid (99942) Apophis with Herschel
• Asteroid triple system 2001 SN263 : surfaces characteristics and dynamical environment
• Dynamical Environment and Surface Characteristics of Asteroid (16) Psyche
• Poincaré surfaces of section around a 3-D irregular body: The case of asteroid 4179 Toutatis

Cited by in corpus (4)

• Refinement of the convex shape model and tumbling spin state of (99942) Apophis using the 2020-2021 apparition data
• Constraining the Interiors of Asteroids Through Close Encounters
• 2001 SN263 -- the contribution of their irregular shapes on the neighborhood dynamics
• Comparison of uncertainty propagation techniques in small-body environment