Description
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The work presented in this thesis is focused on mineralogical studies of the Moon aiming to create maps of iron abundances. We used the data from visible to near-infrared (VIS-NIR) spectrometers on-board Chandrayaan-1 spacecraft, with our major concentration on the Spectrometer InfraRed-2 (SIR-2) data. The SIR-2 on-ground and in-flight calibrations are discussed. The data reduction method for SIR-2 is explained and integration of the datasets obtained by SIR-2, HySI, and M3 instruments are discussed. We focused on the consistent lunar surface measurements collected by the SIR-2 instrument and used the SIR-2 data for the first time to derive the iron content of the Moons surface utilizing 2-m absorption band parameters. Using both 1-m and 2-m absorption band parameters we found a correlation of about 90% between iron abundances estimated by our method and actual laboratory-measured values (from Apollo and Luna datasets). The M3 data measured at the same UTC as the SIR-2 data are used for a comparative study. This study confirms that the 2-m absorption band can be used effectively to estimate the FeO wt% content of lunar surface materials through their NIR reflectance characteristics. Applications of this method would potentially be of great interest to those missions to the Moon and other planetary bodies carrying spectrometers in the wavelength range between 0.9 and 2.5 m.
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The Moon, the only satellite of the Earth, is the most familiar and well-studied celestial body in our solar system. It is an unusual planetary object in terms of its bulk density, size, and origin. The Moon presents pristine information of geologic processes of early planetary evolution because its surface has not been affected by plate recycling, atmosphere, water or life (Hiesinger and Head III 2006). The Moons surface provides a continuous record of the solar-terrestrial processes for which the evidence on Earth has long been erased. Impact cratering, an exterior process, is the most important surface process on the Moon. In terms of composition, the lunar materials both resemble and differ from terrestrial mantle materials. One notable difference is that the Moon is more depleted in volatile elements and enriched in refractory elements than the Earth. The Moon has a composition that cannot be made by any single-stage process from the primodial solar nebula material suggesting that it was subject to additional thermal processing.
