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Information × Registration Number 0309U003106, 0107U000674 , R & D reports Title Astrophysical investigations and monitoring of the Sun, Jupiter and the Moon on data of earthbased and space observations popup.stage_title Дослідження сонячної активності та сонячно-планетних зв'язків. Моделювання фізичних процесів на поверхнях в атмосферах планет. Head Korokhin Victor Valentinovich, Registration Date 04-02-2009 Organization Kharkov Natuional university named after V.N.Karazin popup.description2 Objects of the investigations are the solar corona and chromosphere, the lunar surface and Jovian atmosphere. Goal of the work is monitoring of solar activity, studying of physical properties of the solar corona and chromosphere, atmospheres and surfaces of planets. Methods of investigation are spectrometrical, photometrical and polarimetrical, using theoretical analysis of data, theoretical and digital modeling the processes of light scattering on planets surfaces and in atmospheres. According to the programs of International Solar Service, patrol observations of solar activity were carried out during 53 days. Flares and mass ejections have not fixed. Images of the Sun chromosphere in the lines of Н?, К СаІІ, and HeI ? 1083 mn have been obtained. Results have been sent to WDC-A and SGD. Modernization of software for processing of spectroheliographic observations with 2-dimensional CCD-matrix has been performed. It allows to obtain not only classical spectroheliograms, but also images of the Sun in residual intensities and dopplergrams. After the modernization, spectroheliograph of Astronomical Institute of KhNU allows to obtain of images of the Sun in line HeI ? 1083 nm at the level of leading observatories of the world. Equipment for expedition of Astronomical Institute of KhNU for full solar eclipse August 1, 2008 has been modernized. Changes in time of amplitude of trembling of the Sun limb during the day of partial solar eclipse were observed at Chuguev Observational Station. In spite of bad weather condition, obtained results confirm decreasing of middle amplitude of trembling during a partial solar eclipse. Using the spectra of solar eclipse March 29, 2006, obtained with CCD-photometer with 17 km height resolution, a map of height distribution of absolute values of surface brightness of chromosphere in line D3 НеІ along all western a limb has been constructed. It was shown, that unlike the results of the previous eclipses, helium chromosphere has only one maximum with smaller absolute value and located on greater heights (h ~ 2000km). Gradient of falling of brightness on heights >2000 km is substantially smaller, than in active chromosphere. It confirms a suggestion about absence of lower maximum in the height distribution of helium in a minimum of solar activity and serves as an argument, that helium in lower chromosphere becomes excited by x-ray radiation from the corona with wavelengths < 6nm. Study of presence of ~153-day quasi-periodicity of flow of Solar radiation in radio range F10.7 during ~56 years (18 - 23 sun cycles) was carried out. It was shown, that there are statistically significant peaks in power spectra of the data rows. They correspond to 130 - 180 days periods. Values of amplitudes and periods with maximal amplitude are changing in time. Dependence of amplitudes of peaks on the phase of cycle have not found out. Using the method of superposition of epochs, the dependence of values of indexes F10.7, W and Nx on location on orbits of Mercury, Venus and Earth was studied. It was shown, that asymmetry of distribution of Nx-index values in dependence on heliographic longitudes of planets is statistically significant. For F10.7 та W, statistically significant asymmetry of distribution in dependence on heliographic longitudes of Mercury and Venus has been found out. Seasonal dependence of these indices in relation to the location of the Earth on orbit has been not detected. New polarimetric observations of Jupiter, which continue observational program started in 1981, have been carried out in 2007. Reprocessed data of observations of 2007 at filter "B" (?eff =456 nm) and observations obtained on mountain Maidanak (Uzbekistan) at 2006 (?eff =470 nm) give values of the north-south asymmetry of linear polarization degree: 0.74 % (2006) and -0.3 % .1 % (2007). On the basis of the polarimetric data the study of physical processes in upper atmosphere and in magnetosphere of Jupiter, caused by solar radiation and the Sun activity, was started. It is noted the influence of solar cosmic rays on forming of polarization. Algorithm and software for modeling of light scattering in planet atmospheres have been improved. In order to determine geological composition of Venus surface and temperature lapse rate in lower atmospshere, a modeling of light scattering in Venus atmosphere and comparison of the results with VMC (Venus Express) data were been performed. Using data of absolute photometry of the Moon (Maidanak, 2006), 8 maps of albedo of the Moon for phase angles 27-73° have been obtained. Obtained values of albedo are 20-30% higher than in the Sytinskaya-Sharonov's photometric system, but about 2 times lower than in the "Clementine" system. General behavior of the albedo phase dependence has a good agreement with Lane-Irvine integral phase curve. Mapping of the parameters of phase dependence of brightness of the lunar surface with high-resolution (approximately 4 km near the center of the disk) for ? = 610 nm has been carried out on the basis of this data. Is it shown, that in the range of phase angles ? = 9°-73° phase function with two parameters is not enough for satisfactory description of phase dependence of brightness of the Moon. Otherwise 3-parameters function gives on an order better approximation. Algorithm and software for mapping of the parameters of phase dependence of brightness with taking into account relief of the surface have been developed. It allows to release practically fully the maps of parameters of phase dependence from influence of the relief and obtain the maps of slopes of lunar areas to the normal. Obtained results are stage of development of computer spectrophotometric catalogue for using the Moon as a standard for calibration of Earth-based and space spectrophotometric observations of the Solar system bodies. Product Description popup.authors popup.nrat_date 2020-04-02 Close