Simulation To Lunar Reflection Spectrum Based On Ground-based Observation

The moon is the nearest object to the earth, researches of radiation for the moon never stop. At present, studies of this field are mainly manifested in the acquisition and analysis of lunar satellites and there have been many mature algorithms and research findings, but there are still lacking in terms of ground-based observations at home. Ground-based observations could provide the long-term and stable access for the lunar irradiance and ensure the stability and higher accuracy of data, which contributes to establishment of the object database; at the same time, as a stable source, the simulation of lunar reflection spectrum could also offer the quantitative reference for radiation calibration of earth satellites in the future, which has great significance for the research in the field of moon observation.Simulation of moon spectrum reflection comes down to the atmosphere transmission process simulation calculations, the atmosphere is key factor for radiation transmission, existence of various kinds of atmospheric components will produce the absorption, scattering, refraction effects and so on, so the value of irradiance on earth’s surface would be influenced, and key to this study is how to simulate the atmospheric radiative process quantitatively and accurately.On the premise of related researches, MODTRAN is selected for describing the radiative transfer process of moon based the ground-based observation, some kinds of input parameters will be imported including the atmospheric computing model, absorption and scattering of typical components(H2O、CO2、CH4、N2O、CO) and aerosols, observation geometry, parameters of sensors and so on. After this, the atmospheric attenuation coefficient will be calculated under above conditions, while the sun’s radiance flux and lunar reflectance are known, we could obtain the radiance flux on surface of the earth under the different condition of atmospheric radiation transmission process. According to the predecessors’ research achievements, different combination of atmospheric parameters could result in different transfer processes, so various geometry parameters combination based on observation are established and related calculations conducted, meanwhile the data quantities also be improved, which determines the final fitting process.On the basis of existing conditions, hyperspectral imaging spectrometer composed a band of 400nm-2500 nm will be selected to carry on the ground-based observation experiment on clear night, which is connected to computers by optical fiber, and the lunar reflectance spectrum data would be obtained. Then, compared with the simulation data by MODTRAN, the difference between them could emerge so we could do related adjustments about the input parameters in MODTRAN to get the more accurate simulated results about reflectance spectrum and accomplish the simulation process.RObotic Lunar Observatory(ROLO) in America is at the forefront of research in this field, the simulation of lunar reflectance spectrum based on ground-based observation could provide quantitative reference for related research at home, and offer instructed significance for the calibration and development of moon observation instruments in our country.