Relation between phase function parameters b and c (modified from Sato et al. 2014). The phase function parameters of pure minerals were calculated using the data in Yang et al. (2018). We show the lunar simulated regolith (Zheng et al. 2009; Lin et al. 2020b), and regolith at the Chang’E-3 landing site as well as Apollo soil (Johnson et al. 2013) for comparison. The areas marked with the dashed black and red lines arethe data points derived using the CE-4 reflectance without and with topographic correction, respectively.