Determining the global distribution of minerals on the Moon has been an important goal of lunar science. Hyperspectral remote sensing is an important approach to acquiring minerals on the Moon on the global scale. The...Determining the global distribution of minerals on the Moon has been an important goal of lunar science. Hyperspectral remote sensing is an important approach to acquiring minerals on the Moon on the global scale. The wavelength of the absorption band center is the key parameter for identifying minerals with reflectance spectra as well as remote sensing data. The global absorption center map of the mafic minerals of the Moon was produced for the first time with the Chang’E-1 IIM data. This map shows the global distribution of mafic minerals such as orthopyroxenes, clinopyroxenes, and olivine and even plagioclase feldspar of the Moon. The validation for some representative areas indicates that the global map is reliable and even more detailed than the results derived from Clementine-data. Moreover, our method is insensitive to the topography and viewing and illumination geometries. The global absorption band center map not only contributes to the lunar science research, but also has other implications to be further studied. Moreover, the preprocessing methods such as calibration and correction introduced in this study can be useful in other research with IIM data.展开更多
The interference imaging spectroradiometer (IIM) onboard the first lunar satellite of China "Chang'E-1" can now provide approximately global high spectral and spatial resolution reflectance spectra of th...The interference imaging spectroradiometer (IIM) onboard the first lunar satellite of China "Chang'E-1" can now provide approximately global high spectral and spatial resolution reflectance spectra of the Moon. It is the essential instrument with which to accomplish one of the four missions of the first lunar satellite of China. As the current data provided by the Lunar Exploration Program Center and National Astronomical Observatories (NAOC) are not reflectance and the sensor response is inhomogeneous in the line direction,users can not use the current data directly. Moreover,due to the narrow band range,IIM data cannot cover the absorption peak of the mafic minerals of the Moon completely,which limits its ability for identifying minerals. The main objective of this study is to describe the methods for absolute calibration,correction and acquiring the absorption center of minerals for IIM data. The results from our study show that in the space domain the sensor response decreases toward the left,and in the spectral domain the response of the longer bands is more inhomogeneous than that of the shorter bands. After the calibration and correction,the reflectance of IIM matches the earth-based telescopic spectra well,which suggests the possible use of the processed data in the geological research. A high correlation was found between the absorption center and the wavelength at which the first derivative equals 0,i.e.,the so-called Stagnation Point in the mathematical sense. In the end,we show a preliminary applied study of the two craters with diameter larger than 35 km using the calibrated data. The spectra of IIM data show that the lunar crust has compositional diversity within the km scale. Pure anorthosite may be found on the wall and floor of the Aristarchus crater with the map of absorption center,which indicates that anorthosite is ubiquitously present within the lunar crust. IIM,with its capacity to acquire lunar composition at the regional and global scale,will contribute to the research of lunar origin and展开更多
特发性炎性肌病(idiopathic inflammatory myopathies,IIM)主要包括多发性肌炎(polymyositis,PM)、皮肌炎(dermatomyositis,DM)和包涵体肌炎(inclusion body myositis,IBM)3种类型。近年来IIM的诊断标准也有了新的认识。
Chang’E-1(CE-1)Interference Imaging Spectrometer(IIM)dataset suffers from the weak response in the near infrared(NIR)bands,which are the important wavelength for retrieving the minerals and elements of the Moon.In th...Chang’E-1(CE-1)Interference Imaging Spectrometer(IIM)dataset suffers from the weak response in the near infrared(NIR)bands,which are the important wavelength for retrieving the minerals and elements of the Moon.In this paper,the cross-calibration was implemented to the IIM hyperspectral data for improving the weak response in NIR bands.The results show that the cross-calibrated IIM spectra were consistent to the Earth-based telescopic spectra,which suggests that the cross-calibration yields acceptable results.For further validating the influence of the cross-calibration on the FeO inversion and searching the optimal bands to retrieve lunar FeO contents,four band selection schemes were designed to retrieve FeO using the original and cross-calibrated IIM spectra.By comparing the distribution patterns and histograms of the IIM derived FeO contents with the Clementine derived FeO,the IIM 891 nm band after cross-calibration showed a higher accuracy in the FeO inversion,hence most useful for lunar FeO inversion.展开更多
The imaging interferometer(IIM)aboard the Chang’E-1 lunar orbiter is the first multispectral imaging spectrometer for Chinese lunar missions.Before science applications(e.g.,FeO and TiO2mapping)of the IIM raw data,th...The imaging interferometer(IIM)aboard the Chang’E-1 lunar orbiter is the first multispectral imaging spectrometer for Chinese lunar missions.Before science applications(e.g.,FeO and TiO2mapping)of the IIM raw data,the radiance variation due to changes in illumination and viewing geometry has to be removed from the radiometrically calibrated IIM Level 2A images.To achieve this,we fit the IIM Level 2A radiance data with a Lommel-Seeliger photometric model consisting of an exponential term and a fourth order polynomial in the phase function,without distinguishing between lunar maria and highlands.The exponential and the fourth order polynomial parameters are derived separately by fitting to two datasets divided at a solar phase angle threshold,avoiding a decrease in the phase function close to zero phase angle.Different phase angle thresholds result in coincident fitting curves between 20°and 75°,while large discrepancies occur at other phase angles.Then the derived photometric model is used to normalize the IIM Level 2A data to radiance values at an incidence and phase angle of 30°and emission angle of 0°.Our photometric model is validated by comparing two photometrically normalized IIM radiance spectra covering the same areas,showing a relative deviation consistent with the IIM preflight calibration.展开更多
基金supported by grants from the open fund of the State Key Laboratory for Mineral Deposits Research, Nanjing University (Grant No. 2008-II-03)the National Natural Science Foundation of China (Grant Nos. 40904051 and 40701125)+2 种基金the Macao Science and Technology Development Fund (Grant Nos. 003/2008/A1 and 018/2010/A)the project of China Geological Survey (Grant No. 1212010811050)the National High Technology Research and Development Program of China (Grant Nos. 2008AA12A213 and 2010AA122203)
文摘Determining the global distribution of minerals on the Moon has been an important goal of lunar science. Hyperspectral remote sensing is an important approach to acquiring minerals on the Moon on the global scale. The wavelength of the absorption band center is the key parameter for identifying minerals with reflectance spectra as well as remote sensing data. The global absorption center map of the mafic minerals of the Moon was produced for the first time with the Chang’E-1 IIM data. This map shows the global distribution of mafic minerals such as orthopyroxenes, clinopyroxenes, and olivine and even plagioclase feldspar of the Moon. The validation for some representative areas indicates that the global map is reliable and even more detailed than the results derived from Clementine-data. Moreover, our method is insensitive to the topography and viewing and illumination geometries. The global absorption band center map not only contributes to the lunar science research, but also has other implications to be further studied. Moreover, the preprocessing methods such as calibration and correction introduced in this study can be useful in other research with IIM data.
基金Supported by the Macao Science and Technology Development Fund (Grant No. 003/2008/A1)
文摘The interference imaging spectroradiometer (IIM) onboard the first lunar satellite of China "Chang'E-1" can now provide approximately global high spectral and spatial resolution reflectance spectra of the Moon. It is the essential instrument with which to accomplish one of the four missions of the first lunar satellite of China. As the current data provided by the Lunar Exploration Program Center and National Astronomical Observatories (NAOC) are not reflectance and the sensor response is inhomogeneous in the line direction,users can not use the current data directly. Moreover,due to the narrow band range,IIM data cannot cover the absorption peak of the mafic minerals of the Moon completely,which limits its ability for identifying minerals. The main objective of this study is to describe the methods for absolute calibration,correction and acquiring the absorption center of minerals for IIM data. The results from our study show that in the space domain the sensor response decreases toward the left,and in the spectral domain the response of the longer bands is more inhomogeneous than that of the shorter bands. After the calibration and correction,the reflectance of IIM matches the earth-based telescopic spectra well,which suggests the possible use of the processed data in the geological research. A high correlation was found between the absorption center and the wavelength at which the first derivative equals 0,i.e.,the so-called Stagnation Point in the mathematical sense. In the end,we show a preliminary applied study of the two craters with diameter larger than 35 km using the calibrated data. The spectra of IIM data show that the lunar crust has compositional diversity within the km scale. Pure anorthosite may be found on the wall and floor of the Aristarchus crater with the map of absorption center,which indicates that anorthosite is ubiquitously present within the lunar crust. IIM,with its capacity to acquire lunar composition at the regional and global scale,will contribute to the research of lunar origin and
文摘特发性炎性肌病(idiopathic inflammatory myopathies,IIM)主要包括多发性肌炎(polymyositis,PM)、皮肌炎(dermatomyositis,DM)和包涵体肌炎(inclusion body myositis,IBM)3种类型。近年来IIM的诊断标准也有了新的认识。
基金supported by the National Basic Research Program of China (Grant No. 2010CB951603)Shanghai Science and Technology Support Program Special for EXPO (Grant No. 10DZ0581600)+2 种基金the Open Research Funding Program of KLGIS (Grant No. KLGIS2011A09)the National Natural Science Foundation of China (Grant No. 41172296)the Program for New Century Excellent Talents in University (Grant No. NCET-11-0242)
文摘Chang’E-1(CE-1)Interference Imaging Spectrometer(IIM)dataset suffers from the weak response in the near infrared(NIR)bands,which are the important wavelength for retrieving the minerals and elements of the Moon.In this paper,the cross-calibration was implemented to the IIM hyperspectral data for improving the weak response in NIR bands.The results show that the cross-calibrated IIM spectra were consistent to the Earth-based telescopic spectra,which suggests that the cross-calibration yields acceptable results.For further validating the influence of the cross-calibration on the FeO inversion and searching the optimal bands to retrieve lunar FeO contents,four band selection schemes were designed to retrieve FeO using the original and cross-calibrated IIM spectra.By comparing the distribution patterns and histograms of the IIM derived FeO contents with the Clementine derived FeO,the IIM 891 nm band after cross-calibration showed a higher accuracy in the FeO inversion,hence most useful for lunar FeO inversion.
基金supported by the National Natural Science Foundation of China(11003012,41373068)the Natural Science Foundation of Shandong Province(ZR2011AQ001)+1 种基金Joint Funds of the National Natural Science Foundation of China and the Chinese Academy of Sciences(U1231103)Independent Innovation Foundation of Shandong University(2013ZRQP004)
文摘The imaging interferometer(IIM)aboard the Chang’E-1 lunar orbiter is the first multispectral imaging spectrometer for Chinese lunar missions.Before science applications(e.g.,FeO and TiO2mapping)of the IIM raw data,the radiance variation due to changes in illumination and viewing geometry has to be removed from the radiometrically calibrated IIM Level 2A images.To achieve this,we fit the IIM Level 2A radiance data with a Lommel-Seeliger photometric model consisting of an exponential term and a fourth order polynomial in the phase function,without distinguishing between lunar maria and highlands.The exponential and the fourth order polynomial parameters are derived separately by fitting to two datasets divided at a solar phase angle threshold,avoiding a decrease in the phase function close to zero phase angle.Different phase angle thresholds result in coincident fitting curves between 20°and 75°,while large discrepancies occur at other phase angles.Then the derived photometric model is used to normalize the IIM Level 2A data to radiance values at an incidence and phase angle of 30°and emission angle of 0°.Our photometric model is validated by comparing two photometrically normalized IIM radiance spectra covering the same areas,showing a relative deviation consistent with the IIM preflight calibration.