Abstract:
The aqueous alteration spectral features of carbonaceous chondrites for were studied for future volatile-rich asteroids exploration and remote sensing. The 1-20 μm infrared spectral features and petrographic characteristics of 15 carbonaceous chondrites with different alteration degrees were analyzed, and the spectral variation laws of the aqueous alteration were summarized. The findings demonstrate that as the degree of alteration of carbonaceous chondrites increases, the 3 μm absorption band, which indicates phyllosilicates and water molecules, and the 6 μm absorption band, which indicates only water molecules, both features increasing in strength and absorption centers shift to the short-wave. With more alteration, the 3 μm absorption band sharpens and resembles serpentine’s 3 μm absorption feature. However, as the degree of alteration increases, the 6 μm absorption band shape does not significantly change. The degree of alteration also affects the spectral shape of the 10-13 μm region. This region indicates silicate features. The 12.4 μm /11.4 μm reflectance ratio reduces as a result of the conversion of anhydrous silicates to phyllosilicates. Also discuss possible effects that the spectra and parameters discovered during this study may have on the outcomes from asteroids.