Mid infrared spectra of lunar and analog soils

The mid infrared emittance spectrum contains compositional information about lunar soils. In order to be able to properly interpret remotely obtained data, it was necessary to develop a theoretical model of the emittance of particulate minerals. This theory was shown to simulate the spectra of analog lunar soils satisfactorily provided that good values of the optical constants of the component minerals were available. Optical constants have been obtained for dunite, bytownite, augite, ilmenite, and a mare glass analog during this work. Our first measurements on lunar soils indicated that 67711 is very immature (high contrast) and is dominated by feldspar; that 10084 shows very low contrast with some evidence of pyroxene and feldspar bands. 71061 is intermediate between the other two having a gross similarity to 10084 but with considerably more contrast.