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Lunar glasses are characterized by complex origin (i.e., volcanism or impact), compositional diversity (e.g., picritic, basaltic, or feldspathic), and visible/near‐infrared spectra similarity. This makes it is problematic to distinguish different types of lunar glasses in laboratory and remote data. In this study, we present micro‐FTIR (Fourier Transform Infrared) spectroscopy spectra (550–1450 cm–1) of a suite of lunar volcanic origin glasses (i.e., pyroclastic glasses) and impact‐generated glasses (i.e., mare and highland impact glasses), identified in lunar breccia meteorite Northwest Africa 7948. The results show that lunar pyroclastic glasses, mare impact glasses, and highland impact glasses exhibit different FTIR spectral characteristics: (1) the Christiansen Feature positions of pyroclastic glasses are generally at a longer wavelength (i.e., >~8.3 μm equivalent to <~1,205 cm–1) than the spectra of mare and highland impact‐generated glasses (i.e., <~8.3 μm equivalent to >~1,205 cm–1); (2) a relatively strong minor peak was distinctly observed at longer wavelength (~13.5–16.5 μm equivalent to ~600–750 cm–1) for highland impact glasses. Therefore, new supplementary FTIR diagnostic criteria were proposed to discern different types of lunar glasses. Our studies demonstrated that midinfrared spectra could provide an effective tool to non‐destructively and quickly distinguish lunar glasses in laboratory (e.g., for the future Chang'E‐5 returned soils).

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The phonon dispersions of LiD, LiH and NaH for B1 and B2 phases are computed using density-functional perturbation theory (DFPT) with both local density (LDA) and generalized gradient (GGA) approximations. It is found from the phonon dispersion curves that the B2 phase is unstable at low pressure for all the systems considered. From the vibrational free energy, the coefficient of the linear thermal expansion, the heat capacity and the vibrational entropy as a function of temperature at zero pressure are calculated within the framework of the quasiharmonic approximation. Very good agreement is found for these properties except in the case of the GGA at high temperature. The equation of states for NaH B1 and B2 phases at 300 K and the B1-to-B2 phase transition pressure are in excellent agreement with experimental results. The equation of state for the LiH B1 phase agrees well with experiments and recent theoretical calculations. The estimated B1-to-B2 phase transition pressure (308 GPa) is also in good agreement with other theoretical calculations.

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The formation and distribution of lunar surficial water remains ambiguous. Here, we show the prominence of water (OH/H2O) attributed to solar wind implantation on the uppermost surface of olivine, plagioclase, and pyroxene grains from Chang’E-5 samples. The results of spectral and microstructural analyses indicate that solar wind-derived water is affected by exposure time, crystal structure, and mineral composition. Our estimate of a minimum of 170 ppm water content in lunar soils in the Chang’E-5 region is consistent with that reported by the Moon Minerology Mapper and Chang’E-5 lander. By comparing with remote sensing data and through lunar soil maturity analysis, the amount of water in Chang’E-5 provides a reference for the distribution of surficial water in middle latitude of the Moon. We conclude that minerals in lunar soils are important reservoirs of water, and formation and retention of water originating from solar wind occurs on airless bodies.

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Amorphous Fe73.5Cu1Nb3Si13.5B9 alloys, prepared by a melt-spinning technique, were annealed at a temperature of 823 K under pressures in the range of 1–5 GPa and ambient pressure. The high pressure experiments were carried out in a belt-type pressure apparatus. The microstructure of the annealed alloys has been investigated by x-ray diffraction, electron diffraction, and transmission electron microscopy. Experimental results show that the initial crystalline phase in these annealed alloys is α-Fe solid solution (named as α-Fe phase below), and high pressure has a great influence on the crystallization process of the α-Fe phase. The grain size of the α-Fe phase decreases with the increase of pressure (P). The volume fraction of the α-Fe phase increases with increasing the pressure as the pressure is below 2 GPa, and then decreases (P&gt;2 GPa). The mechanism for the effects of the high pressure on the crystallization process of amorphous Fe73.5Cu1Nb3Si13.5B9 alloy and latent applications of high-pressure annealing amorphous Fe73.5Cu1Nb3Si13.5B9 alloy have been discussed.