Variations in NIR spectral parameters with increasing Fa# values of olivine under different irradiation energy conditions. Images (a) and (b) R₁₉₀₀; (c) and (d) R₂₄₀₀/R₁₉₀₀; (e) and (f) BD₁₀₀₀. The initial olivine is shown in black. Images (a), (c), and (e) show irradiations simulating Phobos conditions, P5mJ (teal line), P25mJ (red line), and P75mJ (brown line). Images (b), (d), and (f) show irradiations simulating Moon conditions, M75mJ (blue dashed line) and M150mJ (purple dashed line). Under Phobos conditions, the decrease in reflectance and increase in R₂₄₀₀/R₁₉₀₀ spectral slope are approximately parallel to the initial olivine with increasing Fa# values. Variations in band depth occured in different Fa# samples, but overall the band depth attenuated after irradiations. Under the Moon conditions, the changes in reflectance, R₂₄₀₀/R₁₉₀₀ spectral slope change, and band depth generally followed the trends of initial olivine, with exceptions in Fa₁₀₀-M75mJ and -M150mJ.