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Information × Registration Number 0207U004736, 0103U000670 , R & D reports Title Composition and surface structure of the Moon according to new optical sounding methods popup.stage_title Head Shkuratov Juriy Grigorovich, Registration Date 14-08-2007 Organization Kharkov national university named after V.N. Karazin popup.description2 A new technique that interpolates available Lunar Prospector Gamma-ray spectrometer (GRS) data using Clementine UVVIS spectral reflectance images was developed. The main idea is to use low resolution GRS data a "Ground truth" to establish relationships linking optical, mineralogical and geochemical information maximizing the respective correlation coefficients. Then the relationships and Clementine UVVIS data are used to derive elemental abundance maps with significantly improved spatial resolution, up to 10 times. As an illustration of the suggested technique, maps for the elements Fe, Ti, Al, Ca, Mg, and O with pixel size 15 km x 15 km are presented. Photometric and polarimetric characteristics of a western part of the lunar disk by Earth-based telescopic data are studied. Earth-based telescopic photometric and polarimetric observations of the Moon were carried out with the telescope Zeiss-600 of Crimean Astrophysical Observatory (Simeiz) in 2001-2003 years. A CCD Line Scan Camera SONY ILX707 was exploited. The western portion of the lunar disk was scanned with the 2048 pixels line at the two wide spectral bands with leff = 0.65 mm and 0.45 mm. Several scans of the Moon were done at the phase angles range 17°- 134°. Distributions of albedo - A for large portion of the western part of the lunar disk at the small phase angle 17°, phase-ratio: ?1= А(87°)/А(17°), ?2=А(134°)/А(87°), and parameter of polarimetric anomalies - ? were obtained by the digital processing. The images include the swirl - Reiner Gamma Formation (RGF). Our results clearly show that on average the RGF in the phase angle range 87° - 134° unexpectedly reveals smaller forward scattering than surroundings. This contradicts to widely believed opinion that the RGF is a forward scatterer. The found effect is due to surface roughness; it does not compensated with the albedo influence. We present results of photometric and polarimetric laboratory measurements of particulate surfaces undergoing different degrees of compression and aerosol particles at a phase angle range from 7° to 150° in red (? = 0.63 ?m) and blue (? = 0.44 ?m) light using two different instruments: Kharkov large-phase-angle photopolarimeter for measurements of surfaces and Amsterdam polar nephelometer for particles in air. We compare phase curves for particulate surfaces with the corresponding measurements for single particles. For photometric data we carried out a comparison between experimental data and the Hapke photometric model. The comparison of measured photometric phase-angle dependencies with the model reveals several model shortcomings. The principal shortcoming is the spectral dependence of the model parameters that should be independent of wavelength. We developed the modification of the T-matrix method that allows fast calculations of scattering properties of particles with irregular shapes. This modification uses the so-called Sh-matrices, the elements of which depend on the shape of particles and do not depend on the particle size or optical constants; i.e., the introduction of Sh-matrices make possible the separation of these parameters within the T-matrix algorithm. For a given shape of a scattering object we calculate the Sh-matrices only once and then can quickly calculate the T-matrix elements for a number of sizes and refractive indices. This, in particular, provide rapid particle-size and refractive index averaging in a particle ensemble. This separation was useful for the derivation of an analytical light-scattering solution for Chebyshev particles. Product Description popup.authors popup.nrat_date 2020-04-02 Close