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Information × Registration Number 0217U000269, 0116U002868 , R & D reports Title Investigation the kinematics of the Galaxy using the proper motions of stars. Detection of anomalies of lunar surface structure using space photometry with high spatial resolution (from GAIA and LRO data). popup.stage_title Head Shulga V. M., Registration Date 25-01-2017 Organization Institute of Radio Astronomy of Sciences of Ukraine popup.description2 ABSTRACT The report on the research: 92 pages, 39 figures, 9 tables, 98 sources. The subject of research - stars, extragalactic objects. Lunar surface and regolith. The goal of the study related to the use of the proper motions of stars was to obtain the kinematic parameters of the Galaxy, in particular the angular velocity of rotation based on proper motions of stars of the new high-density XPM2 catalogue covering the whole sky. The results are presented in 5 publications (2 theses and 3 articles) as well as on 3 oral reports at 2 conferences. For this part of the project over 2016 following results was derived: 1. The program "VSH" in C programming language for calculation coefficients of decomposition of stellar proper motion field into vector spherical harmonics in tangential plane was created. Also the related set of programms in C language was created which include: coordinate conversion from equatorial coordinate system to galactic one ("C-TRANSFORM"), subdividing data into magnitude bins and in each bin splitting the sphere into fields using the Healpix library (HEAL_BIN_MAG). Also programs using the Linux command-line tools reqiured to launch programs created as well as to process data both by Linux and Windows users. The 'PLOTTING' set of programs for automatic plotting figures using data from several files simultaneously was created. The data, if necessary, are approximated by straight lines or mean values in magnitude bins. This program complex is indispensable, for example, in global analysis of behaviour of proper motions through the whole celestial sphere depending on equatorial ?, ? or galactic l, b coordinates or magnitude. The 'PLOTTING' was often used to analize different release versions of the PMA, XPM and others catalogues. The "RPM" program calculating reduced proper motions was written. Because of lack of parallaxes for most of objects in modern catalogues reduced proper motions are statistical means of estimation of distances to objects. Comparing diagrams of reduced proper motion M'V versus colour index J-K with ones absolute magnitude MV versus colour index J-K the calibration of M'V was performed, and it allowed to determine the dividing line bitween red dwarfs and rest of the population of the M'V- (J-K) diagram. The result derivedwas used further in creating the XPMA catalogue. 2. Using the "VSH" program mathematical models of proper motion fields of stars such catalogues as XPM, XPM2, UCAC4, XPMA, TGAS were builded. The dependence of model parameters on magnitude as well as on distance for stars parallaxes of which are known was analised. For TGAS (Tycho-Gaia Astrometric Solution) data Galactic kinematic parameters as a function of distance in the range from 0 pc to 1200 pc as well as on G magnitude were calculated using the program of decomposition into VSH. The method of research - processing observational data, generalization and comparative analysis of data, photographic and CCD astrometry methods, mathematical apparatus of the least square method, data filtration, probability theory and mathematical statistics. The results of the research are partially published, partially prepared for publication and partially are at the analysis stage. They can be made available to all interested organizations and specialists in astrometry, celestial mechanics and stellar astronomy both in Ukraine and abroad. A forecast: elaborating relations between the Hipparcos coordinate system and ICRF2 system as well as elaboratingkinematic parameters of the Galaxy are probable. The aim of the study related to the detection of anomalies in the structure of the lunar surface using high-resolution space photometry, is to create new methods for remote identification of artificial and natural disturbances in the lunar regolith layer with the space mission NASA Lunar Reconnaissance Orbiter (LRO). Obtaining new data on the structure, optical and physical properties of the lunar surface with the use of high-resolution data. Research Methods - the acquisition and analysis of spatial distribution of the phase ratio, of the phase dependences of color-indexes for the study of the photometric properties of the regolith surface of the Moon. The results are present in 7 publications (3 abstracts and 4 articles) as well as at 2 conferences. The project produced the following results: An assessment of the extent and magnitude of changes in the structure of the lunar surface as a result of exposure to it, both natural and anthropogenic factors. For this assessment, the orbital photometry data of high resolution used in conjunction with the method of phase ratios, which allows to evaluate the roughness of the light scattering surface on a scale smaller than the image resolution. It is proved, that the method developed by the authors enables the photometric interpretation of the image of the lunar surface in terms of its roughness . It is shown , that using the method it is possible to identify remotely places of soil taluses and impact melt. The reliability of the new method proved by photometric detection of anomalies , associated with changes in the structure of the surface layer of regolith in places of documented impact of human activity on the lunar regolith . The interpretive framework for analyzing the photometric data of the Moon is developed. In particular, it enables remote identification of areas of formation of new craters , the fall of a comet or meteoroid streams on the surface of the Moon . The mechanism, which can lead to the appearance of dark rays (halo) around young craters is suggested. The mechanism is based on the difference in phase dependencies brightness halos (rays) and their surrounding surfaces. Using the methods of the phase and temporal ratios new natural craters on the lunar surface are explored; dark halo and ray systems of these craters, characterized by a significant tilt of the phase function are found. It is presented a new explanation of the mechanism, which can lead to the appearance of the dark halo and rays around the new newly formed lunar craters. An interpretation of photometric anomalies, associated with the effect of gas jets of landing modules of spacecraft on the lunar surface is presented. It is shown, that the method of phase ratios can be successfully applied not only for the study of landing sites, but also for the slopes of the young lunar craters, where the regolith transport processes can be strongly developed. A method of converting map projection of images, obtained with the wide-field cameras from low orbits, taking into account the influence of topography, is presented. The selection of digital maps of the lunar topography, the most suitable for data processing of LROC WAC camera is discussed. A new method of constructing a seamless mosaic of reflectance distribution for the lunar surface using data from the camera LROC WAC sis developed. New mosaics are used for photometric analysis of anomalies in the lunar Mare Nubium. The presence of the anomaly can be explained by differences of the surface structure of the surrounding regions. This area can be a zone of shallow flooding of raised formation with highland composition. Material of this formation could have been elevated and mixed up with the upper layers of the soil. According LROC WAC camera of spacecraft LRO the effect of coherent backscattering by lunar surface is studied, it was found, that the effect is small in visible light. The width of the opposition surge of coherent backscattering is 1 - 4 °. The maximum amplitude of the spike is close to 8%. It is shown, that the photometric calibration data of LROC WAC is close to the average data of the telescopic absolute photometry. A comparative study of lunar anomalies (so-called red spots) using characteristics , measured by the spacecraft Clementine, LRO, and Chandrayaan - 1 is conducted. North - eastern quadrant of the crater Copernicus shows itself as a red spot on the Moon and is similar to other extrusion of rhyolitic chemical composition. It is shown, that the red spot of the crater Copernicus is produced of rhyolite extrusion by impact. The asymmetry of the anomaly may be associated with a deviation of impactor from the normal fall. The simulation of light scattering by regolith-like particles of irregular shapes, which have a size much larger than the wavelength of incident light with size parameter ?? = 200 is performed using a discontinuous Galerkin method in the time domain. Comparison with DGTD solutions for smoothly faceted particles with one obtained by the geometrical optics model shows a good match for the intensity and polarization curves as a function of the scattering angle. If a surface roughness on the wavelength scale is introduced, the diffuse scattering on rough surfaces is resulted in a smooth and featureless curves for all the elements of the scattering matrix , which is consistent with laboratory measurements of real samples . These project data can be used in the planning and implementation of space missions to the Moon and other atmosphereless bodies of the Solar system by space agencies of the world . Product Description popup.authors Ахметов Володимир Сабірджанович Курбатова Наталія Дмитрівна Федоров Петро Миколайович Цвєткова Вікторія Сергіївна Шульга Валерій Михайлович popup.nrat_date 2020-04-02 Close