Comparison between the mean soil spectrum at the Zhurong landing site and the HWMK 600 spectrum. The red line represents the mean soil spectrum acquired by Zhurong (smoothed and photometrically corrected to i = 30° and e = 0°). The gray line denotes the unsmoothed spectra, while the shaded area indicates one standard deviation. The blue line corresponds to the HWMK 600 spectrum (RELAB ID: capa03, grain size 0–45 μm), converted to RADF by dividing by cos 30°.