Date: 29.11.2017., 15:00

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1. Speaker: Sambarov G.E. 

Title:Probabilistic simulation of dynamics of asteroids with a complex perturbations’ structure

Abstract:

An algorithm for calculation of confidence regions’ displacements of asteroid motion due to motion model errors is proposed. The estimations of these errors’ influence on precision of the construction of initial confidence regions for some asteroids were obtained and nonlinearity of the estimation problem of their motion parameters for each considered motion model was investigated. The features of the orbital evolution of asteroids with a complex perturbation structure, and regular and chaotic regimes of motion are detected at the time intervals under investigation. The numerically-analytical technique for revealing the influence of secular resonances on the orbital evolution of small bodies of the Solar System has been improved and their effect on the asteroid (196256) 2003 EH1 has been studied

2. Speaker: Dr. Emel’yanenko V.V. (INASAN)

Title: The role of encounters with the Sun in the evolution of asteroids and comets

Abstract:

Dynamical processes of the transition of asteroids and comets into orbits with small perihelion distances are studied. For short periods of time (~ thousands of years), these transitions occur efficiently by the action of the Lidov-Kozai secular perturbation mechanism, and at much longer intervals such orbital transformations occur by the action of secular resonances. It is shown that the near-Sun phase in the evolution of small bodies plays an important role in the formation of physical properties, size distribution and dynamical features of near-Earth objects. Observed asteroids have been found, that had orbits with perihelion distances of less than 0.1 au in the recent past. It is revealed that with great probability the Chelyabinsk meteorite passed near the Sun about a million years ago.

3. Speaker: Dr. Emel’yanenko N.Yu. (INASAN)

Title: Models of low-velocity encounters of a small body with planets

Abstract:

The models of low-velocity encounters of a small body with planets are developed. A method for determining the low-velocity encounter of a small body with a planet in the evolution of orbital elements is proposed. The polar orbital coordinates of the quasi-tangency point on the orbit of a small body are determined. The rectangular heliocentric coordinates of the quasi-tangency point on the orbit of the planet are found.  The features of the models with different positions of the quasi-tangency points on the orbit of a small body are analyzed.