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The photometric properties of the uppermost lunar regolith are used in the spectroscopic study. China's Chang'E‐5 (CE‐5) mission successfully landed in the Northern Oceanus Procellarum of the Moon, carrying the scientific payload lunar mineralogical spectrometer (LMS). LMS performed full‐view scanning and obtained the reflectance spectra in various geometric configurations. The photometric properties, including the single‐scattering albedo ω and two parameters of the Henyey‐Greenstein phase function (b, c), were derived. Our modeling results showed weak backward scattering and strong forward scattering properties of the regolith at the CE‐5 landing site. Meanwhile, the asymmetry parameter (−b×c) $(-b\times c)$ indicates that CE‐5 regolith has weaker forward scattering than the Apollo lunar soil samples and the regolith at the Chang'E‐4 landing site. The derived Hapke parameters can be used for comparison with that of the returned lunar sample, supporting further studies of lunar spectroscopy, and can be the ground truth of the CE‐5 landing area. Plain Language Summary: The in‐situ mineral compositions of the lunar regolith can be retrieved using spectral observations with known photometric properties of the lunar surface. The lunar mineralogical spectrometer installed on the Chang'E‐5 lander conducted in‐situ full‐view scanning, and obtained many spectral data. We derived a photometric function using these data to study the properties of the regolith. These findings can be compared to the measured value of the lunar returned samples of CE‐5 to support future spectroscopy research and provide a better understanding of the mineralogical information at the CE‐5 landing area. Key Points: The photometric properties of the lunar regolith are revealed by in‐situ spectrum data from the Chang'E‐5 Lunar Mineralogical SpectrometerThe derived photometric parameters contribute to a better understanding of the properties of the regolith on the near side of the moonThe forward scattering was dominant in the landing site, consistent with the compositions of the lunar samples returned from the Chang'E‐5 [ABSTRACT FROM AUTHOR]

In-situ measurements of the spectral information on the lunar surface are of significance to study the geological evolution of the Moon. China's Chang'E-4 (CE-4) Yutu-2 rover has conducted several in-situ spectral explorations on the Moon. The visible and near-infrared imaging spectrometer (VNIS) onboard the rover has acquired a series of in-situ spectra of the regolith at the landing site. In general, the mineralogical research of the lunar surface relies on the accuracy of the in-situ data. However, the spectral measurements of the Yutu-2 rover may be affected by shadows and stray illumination. In this study, we analyzed 106 CE-4 VNIS spectra acquired in the first 24 lunar days of the mission and noted that six of these spectra were affected by the shadows of the rover. Therefore, a method was established to correct the effects of the rover shadow on the spectral measurements. After shadow correction, the FeO content in the affected area is corrected to 14.46 wt.%, which was similar to the result calculated in the normal regolith. Furthermore, according to the visible images, certain areas of the explored sites were noted to be unusually bright. Considering the reflectance, geometric information, and shining patterns of the multi-layer insulation (MLI), we examined the influence of the specular reflection of the MLI on the bright spot regionsd, and found that the five sets of data were likely not affected by the specular reflection of the MLI. The results indicated that the complex illumination considerably influences the in situ spectral data. This study can provide a basis to analyze the VNIS scientific data and help enhance the accuracy of interpretation of the composition at CE-4 landing sites. [ABSTRACT FROM AUTHOR]