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Information × Registration Number 0218U001430, 0115U000482 , R & D reports Title Determination of physical and dynamical properties of near-Earth asteroids popup.stage_title Head Belskaya Irina Nikolaevna, Registration Date 13-03-2018 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of the study is near-Earth asteroids (NEA), including potentially dangerous asteroids that could pose a threat to human civilization in the event of a collision. The aim of the work is to determine the physical, optical and dynamic characteristics of the selected NEAs, and to investigate the influence of the YORP-effect on the asteroid spin rate. Research techniques are photometric and polarimetric observations, numerical simulation, and statistics of observational data. During 235 nights, the photometric observations of 80 NEAs have been carried out. The lighturves were obtained, rotation periods were determined, and estimates of size and elongation of body shapes were made. Observations of ten binary NEAs have been obtained, and five asteroids suspected to be a binary. For the first time, observations of 21 small NEAs were made and an extreme axial rotation determined for 9 of them. Photometric observations of 14 small main belt asteroids with diameters smaller 15 km have been carried out, which are members of very young clusters (mini-families) that were separated less than 1 million years ago. The data are obtained for several NEAs, for which finding YORP-effect is expected. An analysis of the parameters of rotation and elongation of shapes of secondary bodies in the asteroid binary systems is performed. For the first time, measured values of the polarization maxima for the low-albedo asteroid and for the mean-albedo Q-type asteroid. The albedo and diameters of potentially dangerous NEAs (85989) 1999 JD6 and (214869) 2007 PA8 were first determined. The polarimetric technique for determining albedo of the asteroids according to observation data at large phase angles has been improved and it is proved that the technique is most effective for determining albedo and sizes of potentially dangerous NEAs. A unified theory is proposed for taking into account of the YORP and Yarkovsky effects, which allows to determine the rotational torque and the forces acting on the asteroid, in the form of integrals on the surface of the asteroid. The proposed approach can be used to calculate the rotational torque of the YORP and the Yarkovsky forces acting on any asteroid. Obtained results are interesting to solve global problems associated with a potential hazard from NEAs for the people civilization in the event of a collision. Product Description popup.authors І. Бельська А. Довгопол В. Чорний В. Шевченко О. Голубов О. Сергеєв С. Величко Т. Громакіна У. Пирогова Ю. Круглий popup.nrat_date 2020-04-02 Close