Search academic texts

Information × Registration Number 0217U001234, 0115U000482 , R & D reports Title Determination of physical and dynamical properties of near-Earth asteroids popup.stage_title Head Belskaya Irina Nikolaevna, Registration Date 31-01-2017 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of study is near-Earth asteroids (NEAs), including potentially hazardous asteroids that could pose a threat to human civilization in the event of a collision. The aim is to determine the physical, optical and dynamic properties of selected asteroids approaching the Earth and study the influence YORP effect on the rotation speed of asteroids. Photometric observations of 22 near-Earth asteroids (NEAs) were carried out during 82 nights. We obtained lightcurves of asteroids, defined their rotation periods and made estimations of their sizes and shapes. New observations were obtained for four binary asteroids, and one asteroid was suspected to be a binary object. We made first photometric observations of very small NEAs and small main belt asteroids, which belong to clusters originated less than 1 million years. We obtained the data for NEAs, for which the YORP effect is expected to be discovered. The analysis of rotation and shape elongation parameters for the secondary bodies in the binary systems were made. A unified theory to take into account both the YORP and Yarkovsky's effects was proposed which allows to determine the torque and forces acting on an asteroid as integrals over the asteroid's surface. Integrals were calculated numerically and their dependence on free parameters was studied. The approach can be used to calculate the torque of YORP effect and Yarkovsky's forces acting on any asteroid. The obtained results can be used to solve the applied problems connected with the assessment of the potential danger of NEAs for our civilization. Product Description popup.authors І. Бельська А. Довгопол О. Голубов У. Пирогова Ю. Круглий popup.nrat_date 2020-04-02 Close