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Information × Registration Number 0221U101168, 0118U002019 , R & D reports Title Physical properties of near-Earth asteroids by means of observations and numerical simulations popup.stage_title Head Belska Iryna M, Registration Date 15-01-2021 Organization V.N. Karazin Kharkiv National University popup.description2 Photometric observations of 140 NEAs were carried out during 380 nights, including 29 newly discovered and several dozen potentially dangerous asteroids. Observations were made using telescopes in Ukraine, Bulgaria, Georgia, Italy, Kazakhstan, Mexico and Uzbekistan within the framework of international cooperation. For the first time, the rotation periods of 42 asteroids were determined or estimated. The rotation of 35 extremely small NEAs with diameters less than 500 m was studied, of which 16 asteroids were found to be ultra-fast rotators with periods less than 2.2 hours. The optical characteristics of the surfaces of two associated NEAs (3200) Phaethon and (155140) 2005 UD were studied. New high-precision photometric data were obtained for six binaries in order to detect the BYORP effect, and for 17 asteroids to search for the YORP effect. For the first time, polarimetric observations of NEAs (18736) 1998 NU, (65803) 1999 KW4 and (155140) 2005 performed, as well as for two space mission targets (101955) Bennu and (3200) Phaethon, in order to determine their albedo and size. It was found that the maximum linear polarization of low-albedo asteroids can reach record high values of more than 45%. Acceleration of the rotation of the asteroid Bennu has been discovered, which is associated with the influence of both the normal YORP effect and the tangential component TYORP. A theoretical analysis was made of the effect of TYORP on an asteroid taking into account the size and shape of the boulders at its surface and the effect of mutual shading. New types of equilibrium for synchronous and single-synchronous binary asteroids under the YORP effect and tidal forces have been found. The conditions and probability of their occurrence have been investigated. A theoretical model of the evolution of the rotation rate of asteroids has been developed, taking into account both the normal and tangential YORP effects, as well as collisions. Product Description popup.authors Golubaev Oleksandr V Golubov Oleksiy A. Kyrylenko Ihor I Krugly Yurij M. Mykhailova Sofia S. Slyusarev Ivan G Chiorny Vasyl G Shevchenko Vasyl G popup.nrat_date 2021-01-15 Close