In situ optical measurements of Chang'E-3 landing site in Mare Imbrium: 1. Mineral abundances inferred from spectral reflectance

The visible and near‐infrared imaging spectrometer on board the Yutu Rover of Chinese Chang'E‐3 mission measured the lunar surface reflectance at a close distance (~1 m) and collected four spectra at four different sites. These in situ lunar spectra have revealed less mature features than that measured remotely by spaceborne sensors such as the Moon Mineralogy Mapper instrument on board the Chandrayaan‐1 mission and the Spectral Profiler on board the Kaguya over the same region. Mineral composition analysis using a spectral lookup table populated with a radiative transfer mixing model has shown that the regolith at the landing site contains high abundance of olivine. The mineral abundance results are consistent with that inferred from the compound measurement made by the on board alpha‐particle X‐ray spectrometer. Key Points We obtained in situ visible‐NIR reflectance spectra of the lunar surface at Chang'E‐3 landing site These in situ spectra have less mature features than that measured remotely Using the spectral lookup table, we identified large amount of olivines