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Information × Registration Number 0210U001460, 0107U000671 , R & D reports Title Optical properties of planetary bodies dust manties popup.stage_title Head Shkuratov Yuriy, Registration Date 17-02-2010 Organization Kharkov National University named after V.N. Karazin popup.description2 A new research technique is polarimetric imaging observation of Mars and Moon. The main idea is polarimetric imaging observation of Mars and Moon with the Hubble Space Telescope, orbital spacecraft Clementine and Earth-based telescopes. We report results of polarimetric imaging observations of Mars with the Hubble Space Telescope during the 2003 opposition. Through careful calibration, the observations with the ACS camera allow measurements of the polarization degree with an absolute accuracy better than 0,5% and detection of features with polarization degree contrast as small as 0,2%. The general distribution of linear polarization parameters over the Mars disk and their dependence on phase angle and wavelength are well explained qualitatively by a combination of scattering separately by the Martian surface and atmosphere. We have discovered transient polarization phenomena interpreted as clouds that are best observed in ultraviolet light. These clouds are optically thin but strongly polarizing, and their origin may be related to atmospheric ice condensation processes. We report results of telescope polarimetric imaging of the Moon with a CCD LineScan camera at phase angles near 88 grad. This allows measurements of the polarization degree with an absolute accuracy better than 0,5% and detection of features with polarization contrast as small as 0,1%. The measurements were carried out in two spectral bands centered near 0,65 mkm and 0,42 mkm. Parallax offsets of the surface topography for nadir looking Clementine data and new oblique HST observations allow mapping altitudes for the region of Apollo-17 landing site with resolution near 100 m. Application of Sh-matrices in scattering of electromagnetic waves by particles of irregular shapes. We consider a specific example of expanded boundary conditions method modified with introduction of so-called Sh-matrices whose elements depend only on the shape of a particle and do not depend on its size or optical constants. This allows one to calculate Sh-matrices only once and then to find the intensity and degree of linear polarization for any size parameter and refractive index of particles. In some cases using of Sh-matrices suggests the analytical solution of scattering problem. In this paper the solution for the particles that look like seashells is obtained. It is shown that with increasing of the parameter characterizing deviation from spherical shape, the number of resonances on curves and their amplitude decrease. Product Description popup.authors Бондаренко С. Герасименко С. Кайдаш В. Овчаренко А. Опанасенко М. Опанасенко О. Петров Д. Псарьов В. Станкевич Д. Старухіна Л. Сучкова Т. Шкуратов Ю. popup.nrat_date 2020-04-02 Close