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Information × Registration Number 0201U003734, 0199U004411 , R & D reports Title Astrophysical investigations of Moon and planets popup.stage_title Head Akimov L.O., Registration Date 17-04-2001 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of investigations are the Moon, Jupiter, Galilean satellites of Jupiter, aerosol and dust particles of Solar system. Goal of the work is research of optical properties of planets atmospheres and surfaces, development of theory of light scattering by systems of interacting scatterers. Methods of investigation are photometrical and polarimetrical, using theoretical analysis of data, theoretical and digital modeling the processes of light scattering on planets surfaces. It has been shown that brightness drop to photometrical poles of the Moon increases with phase angle, and that this effect is mainly formed by mesorelief of surface. Multiple scattering makes small contribution to behavior of latutudinal brightness distribution. Results of laboratory measurements of specimens give the possibility to understand a character of influence of surface albedo and relief on light reflection law. It has been also shown, that it is more suitable to use empirical Akimov's formula to describe brightness distri bution over lunar disk, then Hapke's formula. Using results of 1981-1999 years observations of Jupiter, seasonal variations of North-South asymmetry of polarized radiation of high-latitudinal regions of Jupiter have been discovered for the first time. They may be credited with variations of insolation of Jupiter. On average magnitude of asymmetry is 0.5% of polarization. Using results of 1998-year observations of Jupiter, anticorrelation of longitudinal variations of polarization degree for north and south high latitudes has been discovered. Probably it reflects longitudinal distribution of intensity of surface magnetic field of Jupiter for corresponding north and south regions of the planet. Processing data of CCD-observations of Galilean satellites of Jupiter for studying microeffects of negative part of phase dependence of polarization have been carried out. Undoubtedly, there is a sharp peak of negative polarization centered at about 0.5-0.6 degree, which is superimposed on the negative branch of the regu lar phase dependence of polarization. New optical-mechanical device for fast CCD-photopolarimeter has been developed and produced. Significant modernization of software complex IRIS for photometrical data processing has been carried out. Equations for description of multiple light backscattering by layer of medium with arbitrary thickness have been obtained. Comparison of effect of known interference mechanism and peculiarity of near field scattering on forming cooperative effects by closely packed systems of particles is given. Strict equations of multiple light scattering by sufficiently rarefied layer of medium with arbitrary thick ness. Product Description popup.authors popup.nrat_date 2020-04-02 Close