Cosmic dust are extraterrestorial particles less than 1 mm meter, coming from a wide range of possible parental sources such as Comets, Asteroids, Moon, Mars and an interstellar stream of dust. They would provide valuable evidence on the origin of solar system that cannot be derived from meteorites. In the present paper, collection sites and methods of cosmic dust are introduced including those from and by which the first Japanese cosmic-dust collection was recovered. Then, origin and formation process of cosmic dust is discussed based on the mineralogical and compositional data taken by the recently innovated techniques for the analyses of very small particles.

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Remote sensing is the necessary method to explore the moon and planets. Small planets such as moon and asteroids do not have the biological obstacles and atmosphere which absorb electromagnetic reflection and emission. The moon and asteroids have the naked surface of rocks and regolith to be measured the surface characteristics by remote sensing. The important resource materials can be obtained in the space as water and helium-3 which will be used for the future nuclear fusion reactor rather than rare metals and unknown minerals. The constructive materials are also the candidates of resources in the space. The resources in the space will be constrained by the type of industries and human activities in it.

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Most of rock-forming minerals show characteristic absorption features in the visible and near-infrared wavelength regions. Especially, silicates such as olivine and pyroxene show clear absorption bands due to Fe²⁺, which change in wavelength position and strength as their Fe/Mg ratios change. Also, structural change by shock can alter absorption band shapes as seen in plagioclase-muskelynite series. Such changes can be readily quantified using the Modified Gaussian Model. Also, mineral mixing ratios and grain size and shape of each mineral cause specific changes in reflectance spectra, which can be simulated by photometric models. As a special complication of planetary surface regoliths, spaceweathering effects have to be removed from the reflectance spectra.

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The resolution and precision of X-ray powder diffraction data of a silicon standard obtained by a Gandolfi camera were examined by comparing with those obtained by a diffractometer. The peak width (FWHM) and integral breadth of reflections obtained by a Gandolfi camera take vales similar to those obtained by a diffractometer. The reflections of a Gandolfi camera have symmetrical profiles in contrast to the asymmetric ones of a diffractometer. The peak positions can be determined with an error less than 0.01°(2θ) even by using a Gandolfi camera. These results suggest that precise X-ray diffraction analysis can be made also for a very small mineral, 10-100μm in size, by a Gandolfi camera.

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Recent advance on X-ray fluorescence, diffraction and absorption analyses of the earth and planetary materials using synchrotron radiation were overviewed. SR-XRF technique is suitable for nondestructive trace element analysis and chemical state analysis of the geological samples. Utilization of X-ray microbeam also allows us to carry out two-dimensional analysis of trace elements in ppm level in a few micron regions. Characteristics of the SR-XRF techniques were illustrated through the application of the methods to lunar rocks, cosmic dusts, and Banded Iron Formation. New features of the 3rd generation SR light source, SPring-8, and its perspective are described.

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Neutron activation analysis (NAA) is one of the most sensitive methods for determining concentration of elements. In NAA, two kinds of gamma-ray, prompt gamma and decay gamma-rays, can be used. NAA involving the measurement of prompt gamma-ray is called (neutron-induced) prompt gamma-ray analysis (NIPGA or PGA). There are two procedures in NAA using decay gamma-ray, instrumental NAA (INAA) and radiochemical NAA (RNAA). In this paper, each method of NAA including PGA is briefly described. In consideration of the extraterrestrial material to be returned from space by future space mission program, an effective analytical scheme is proposed both for the primary description and for the intensive study of chemical composition. Assuming that the returned material is small (say, smaller than mg-order), a practical procedure of INAA was examined by using cosmic spherules weighing less than 1 mg. The Allende powder sample prepared by the Smithsonian Institution was proved to be effectively used as a reference standard in INAA of small samples.

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Extraterrestrial organic matter has been greatly interested in with relevance to prebiotic evolution of organic matter and origins of life. Since the organic matter in extraterrestrial material is a mixture of many kinds of organic compounds, wet analytical methods are most suitable for the analyses of these compounds. The methods include extraction of soluble organic matter, chromatographic separations into fractions, and molecular identification by analytical instruments. They also allow to separate enantiomers of amino acids, and to determine isotopic compositions of specific compounds. The experimental details should be optimized for detection of compounds as many as possible. They should be carried out very carefully in order to minimize possible terrestrial contamination.

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　関連分野からのサンプル計画への期待に関して,次の4氏よりパネラーとして発言があった.ここでは,各氏の発言を簡単にまとめておく

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