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Information × Registration Number 0224U000849, 0121U109815 , R & D reports Title Dynamics and kinematics of near-Earth asteroids under the action of non-gravitational forces popup.stage_title Head Belska Iryna М., д.ф.-м.н. Registration Date 14-01-2024 Organization V.N. Karazin Kharkiv National University popup.description2  New high-precision photometric data have been obtained for 131 near-Earth asteroids, of which 16 are newly discovered objects and 68 are potentially hazardous asteroids. The observations were conducted over 296 nights within the international cooperation on 16 telescopes at 12 observatories around the world. For the first time, the rotation periods of 43 asteroids have been determined. The rotations of 48 very small near-Earth asteroids with diameters of less than 500 meters were studied, and 11 of them were found to have super-fast rotation. The value of YORP effect responsible for the acceleration of rotation was first determined for (10115) 1992 SK, and was reliably measured for (1620) Geographos and (1685) Toro. Utilizing long-term photometric observations and available radar data, a physical model for the potentially hazardous asteroid (23187) 2000 PN9 was created. The analysis revealed that the asteroid exemplifies YORP equilibrium. Polarimetric observations were carried out for the potentially hazardous asteroid (159857) 2004 LJ1, as well as for the binary asteroid (65803) Didymos, the target of the DART space mission, both before and after the collision with the spacecraft. Variations in the degree of linear polarization over the surface of Didymos after a collision were found, which may be associated with an uneven distribution of dust across its surface. An analytical model of the tangential YORP effect was formulated for the arbitrary shape of an asteroid's regolith surface with a given spectrum of irregularities. Its application will improve the predictions of the evolution of the rotational state of asteroids. A new method for calculating the Yarkovsky effect is proposed, taking into account the shape of the asteroid and the thermal properties of its surface. Calculations for well-studied in-situ asteroids confirmed the reliability of the method. The use of the new method will be aimed at improving the modeling of the dynamics of near-Earth asteroids. Product Description popup.authors Golubov Оleksiy A Kyrylenko Ivan H. Krugly Yurij M. Mikhalchenko Olga I. popup.nrat_date 2024-01-14 Close