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Hyperspectral Imager Suite (HISUI) is a hyperspectral sensor for a remote sensing on the International Space Station (ISS). HISUI is composed of one radiometer that obtains spectral images of 185 bands from the visible to shortwave-infrared region with the ground sampling distance (GSD) of 20 meters for the cross track and 31 meters for the along track. The sensor system is the follow-on mission of the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) in the visible to shortwave infrared region. The observation data of the hyperspectral sensor is expected to an important role in the future spatial-spectral data for the resource exploration, disaster monitoring, environmental observation, agriculture, forestry and fisheries, etc. The tests of a flight model of HISUI have been carried out successfully in 2019 and HISUI is operating on the ISS. This paper describes the design and the performances of the flight model of HISUI and also presents radiometric performances in orbit.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Visible and Near Infrared Radiometer (VNIR) is the remote sensing equipment which has 3 spectral bands and one along-track stereoscopic band radiometer. ASTER VNIR’s planned long life design (more than 5 years) is successfully achieved. ASTER VNIR has been imaging the World-wide Earth surface multiband images and the Global Digital Elevation Model (GDEM). VNIR data create detailed world-wide maps and change-detection of the earth surface as utilization transitions and topographical changes. ASTER VNIR’s geometric resolution is 15 meters; it is the highest spatial resolution instrument on NASA’s Terra spacecraft. Then, ASTER VNIR was planned for the geometrical basis map makers in Terra instruments. After 15-years VNIR growth to the standard map-maker for space remote-sensing. This paper presents VNIR’s feature items during 15-year operation as change-detection images , DEM and calibration result. VNIR observed the World-wide Earth images for biological, climatological, geological, and hydrological study, those successful work shows a way on space remote sensing instruments. Still more, VNIR 15 years observation data trend and onboard calibration trend data show several guide or support to follow-on instruments.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a high-resolution optical sensor system that can observe in a wide region from the visible and near-infrared, the short wavelength infrared to the thermal infrared with 14 spectral bands on board of NASA’s Terra spacecraft for Earth Observing System (EOS) “A mission to planet earth." ASTER achieved 5 years mission success on orbit operation normally which is the specified target after launched on December, 1999. And after through 10 years continuous orbit operation, ASTER has still operating the long life observation of extra success to be 15 years in total on December, 2014. As for ASTER instrument that is composed of 3 radiometers; the Visible and Near Infrared Radiometer (VNIR) with 3 bands, the Short Wavelength Infrared Radiometer (SWIR) with 6 bands, the Thermal Infrared Radiometer (TIR) with 5 bands, overall ASTER long life data taken by 15 years onboard operation has been reviewed from the point of view of the health and safety check by Telemetry (TLM) data trend, the function and performance evaluation by observation data trend, the onboard calibration and verification by periodic Calibration(CAL) data trend. As a result, the radiometric degradation of VNIR and TIR and the temperature rise of SWIR detector were identified as significant challenges. The countermeasure plan towards the end of mission was clarified and also the novel lessons learned was verified.

ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) System is operating more than 15 years since launched on board of NASA’s Terra spacecraft in December 1999. ASTER System is composed of 3 radiometers (VNIR (Visible and Near Infrared Radiometer), SWIR (Short-Wave Infrared Radiometer), and TIR (Thermal Infrared Radiometer)), CSP (Common Signal Processor) and MSP (Master Power Supply). This paper describes the ASTER System operating history and the achievement of ASTER System long term operation since the initial checkout operation, the normal operation, and the continuous operation. Through the 15 years operation, ASTER system had totally checked the all subsystems (MPS, VNIR, TIR, SWIR, and CSP) health and safety check using telemetry data trend evaluation, and executed the necessary action. The watch items are monitored as the life control items. The pointing mechanics for VNIR, SWIR and TIR, and the cooler for SWIR and TIR are all operating with any problem for over 15 years. In 2003, ASTER was successfully operated for the lunar calibration. As the future plan, ASTER team is proposing the 2nd lunar calibration before the end of mission.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a high spatial resolution optical sensor for observing the Earth carried on the National Aeronautics and Space Administration Terra satellite. ASTER consists of three radiometers covering the following regions: visible and near-infrared (VNIR), shortwave infrared (SWIR), and thermal infrared (TIR). The preflight calibration of VNIR and SWIR utilized standard large integrating spheres whose radiance levels were traceable to primary standard fixed-point blackbodies. The onboard calibration devices for the VNIR and SWIR consist of two halogen lamps with photodiode monitors. In orbit, all three bands of the VNIR showed rapid decreases in the output signal while all SWIR bands remained stable. The TIR onboard blackbody was calibrated against a standard blackbody from 100-400 K in a vacuum chamber before launch. The TIR is unable to see the dark space. The temperature of the TIR onboard blackbody remains at 270 K for a short-term calibration to determine any offset and is varied from 270-340 K for a long-term calibration of both the offset and gain. The long-term calibration just after launch was consistent with the prelaunch calibration but then showed a steady decrease of the TIR response over the five years of operation to date.

The Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) is one of the five sensors on the NASA’s Terra satellite on orbit since December 1999. ASTER consists of three radiometers, the Visible and Near InfraRed (VNIR), the Short-Wave InfraRed (SWIR) and Thermal InfraRed (TIR) whose spatial resolutions are 15 m, 30 m and 90 m, respectively. Unfortunately the SWIR image data are saturated since April 2008 due to the offset rise caused by the cooler temperature rise, but the VNIR and the TIR are taking Earth images of good quality. The VNIR and the TIR experienced responsivity degradation while the SWIR showed little change. From the lamp calibration, Band 1 decreased the most among three VNIR bands and 31% in thirteen years. The VNIR has the electrical calibration mode to check the healthiness of the electrical circuits through the charge coupled device (CCD). Four voltage levels from Line 1 to Line 4, which are from 2.78 V to 3.10 V, are input to the CCD in the onboard calibration sequence and the output digital numbers (DNs) are detected in the images. These input voltages are monitored as telemetry data and have been stable up to now. From the electrical calibration we can check stabilities of the offset, gain ratio and gain stability of the electric circuit. The output level of the Line1 input is close to the offset level which is measured while observing the earth at night. The trend of the Line 1 output is compared to the offset level. They are similar but are not exactly the same. The trend of the even pixel and odd pixel is the same so the saturated offset levels of the odd pixel is corrected by using the even pixel trend. The gain ratio trend shows that the ratio is stable. But the ratio values are different from those measured before launch. The difference comes up to 10% for the Band 2. The correct gain ratio should be applied to the vicarious calibration result because the onboard calibration is measured with the Normal gain whereas the vicarious calibration often measures with the High gain. The cause of the VNIR responsivity degradation is not known but one of the causes might be the change of the electric circuit. The band 3 gain shows 16 % decrease whereas the gain changes of the band 1 and band 2 are 5% to 8%. The responsivity decrease after 1000 days since launch might be controlled by the electric circuit change.

The ASTER is a high-resolution optical sensor for observing the Earth on the Terra satellite launched in December1999. The ASTER consists of three radiometers. The VNIR has three bands in the visible and near-infrared region, the SWIR has six bands in the shortwave infrared region, and the TIR has five bands in the thermal infrared region. The onboard calibration devices of the VNIR and SWIR were halogen lamps and photodiode monitors. In orbit three bands of the VNIR showed a rapid decrease in the output signal. The band 1, the shortest wavelength, decreased most to 70% in twelve years. The temperature of the onboard blackbody of the TIR is varied from 270 K to 340 K in the long term calibration for the offset and gain calibration. The long term calibration of the TIR showed a decrease in response after launch. The decrease was most remarkable at band 12 decreasing to 60% in eleven years. The degradation spectra of the TIR shows that the possible causes of the degradation might be silicone and hydrazine. ASTER onboard calibration is normally carried out once in 49 days but additional onboard calibrations were added just before and after the inclination adjustment maneuver (IAM) to check the effect on the RCC. This experiment was carried out three times for each IAM in the fiscal year 2011. The result showed that the change in the RCC was small for both VNIR and TIR.

HISUI (Hyperspectral Imager SUIte) is the next Japanese earth observation sensor, which consists of hyperspectral and multispectral sensors. The hyperspectral sensor is an imaging spectrometer with the VNIR (400-970nm) and the SWIR (900-2500nm) spectral channels. Spatial resolution is 30 m with swath width of 30km. The spectral resolution will be better than 10nm in the VNIR and 12.5nm in the SWIR. The multispectral sensor has four VNIR spectral bands with spatial resolution of 5m and swath width of 90km. HISUI will be installed in ALOS-3 that is an earth observing satellite by JAXA. It will be launched in FY 2015. This paper is concerned with the effect of temperature on onboard calibration reference material (NIST SRM2065) for spectral response functions (SRFs) retrieval of the hyperspectral sensor. Since the location and intensity of absorption features are sensitive to material temperature, the estimated center wavelength and bandwidth of the SRFs may include the uncertainty. Therefore, it is necessary to estimate the deviation of the wavelength and the bandwidth broadening of the SRFs when the material temperature changes. In this paper we describe the evaluation of uncertainty of the SRF’s parameters retrieval and show some simulation’s results.

The hyper-multi spectral mission named HISUI (Hyper-spectral Imager SUIte) is the next Japanese earth observation project. This project is the follow up mission of the Advanced Spaceborne Thermal Emission and reflection Radiometer (ASTER) and Advanced Land Imager (ALDS). HISUI is composed of hyperspectral radiometer with higher spectral resolution and multi-spectral radiometer with higher spatial resolution. The development of functional evaluation model was carried out to confirm the spectral and radiometric performance prior to the flight model manufacture phase. This model contains the VNIR and SWIR spectrograph, the VNIR and SWIR detector assemblies with a mechanical cooler for SWIR, signal processing circuit and on-board calibration source.

The ASTER Instrument is one of the five sensors on the NASA’s Terra satellite on orbit since December 1999. ASTER consists of three radiometers, VNIR, SWIR and TIR whose spatial resolutions are 15 m, 30 m and 90 m, respectively. Unfortunately SWIR stopped taking images since May 2008 due to the offset rise caused by the detector temperature rise, but VNIR and TIR are taking Earth images of good quality. VNIR and TIR experienced responsivity degradation while SWIR showed little change. Band 1 (0.56 μm) decreased most among three VNIR bands and 30 % in twelve years. Band 12 (9.1 μm) decreased 40 % and most among five TIR bands. There are some discussions of the causes of the responsivity degradation of VNIR and TIR. Possible causes are contamination accretion by silicone outgas, thruster plume and plasma interaction. We marked hydrazine which comes out unburned in the thruster plume during the inclination adjust maneuver (IAM). Hydrazine has the absorption spectra corresponding to the TIR responsivity degradation in the infrared region. We studied the IAM effect on the ASTER by allocating the additional onboard calibration activities just before and after the IAM while the normal onboard calibration activity is operated once in 49 days. This experiment was carried out three times in fiscal year 2011.

HISUI (Hyper-spectral Imager SUIte), which is the next Japanese earth observation project, has been developed under the contract with Ministry of Economy, Trade and Industry(METI) and New Energy and Industrial Technology Development Organization(NEDO). HISUI is composed of hyper-spectral sensor and multi-spectral sensor. The hyperspectral sensor is an imaging spectrometer with two separate spectral channels: one for the VNIR range from 400 to 970 nm and the other for the SWIR range from 900 to 2500 nm. Ground sampling distance is 30 m with spatial swath width of 30 km. The spectral sampling will be better than 10 nm in the VNIR and 12.5 nm in the SWIR. The multi-spectral sensor has four VNIR spectral bands with spatial resolution of 5m and swath width of 90 km. HISUI will be installed in ALOS-3 that is an earth observing satellite in the project formation phase by JAXA in FY 2015. This paper is concerned with the retrieval of spectral response functions (SRF) for the hyper-spectral sensor. The center wavelength and bandwidth of spectral response functions of hyper-spectral sensor may shift and broaden due to the distortion in the spectrometer, the optics and the detector assembly. Therefore it is necessary to measure or estimate the deviation of the wavelength and the bandwidth broadening of the SRFs. In this paper, we describe the methods of retrieval of the SRF's parameters (Gaussian functions assumed) by means of onboard calibration sources and we show some simulation's results and the usefulness of this method.

The hyper-multi spectral mission named HISUI (Hyper-spectral Imager SUIte) is the next Japanese earth observation project that will be on board ALOS-3 satellite. This project is the follow up mission of the Advanced Spaceborne Thermal Emission and reflection Radiometer (ASTER). HISUI is composed of hyperspectral radiometer with higher spectral resolution and multi-spectral radiometer with higher spatial resolution. The functional evaluation model is under development to confirm the spectral and radiometric performance prior to the flight model manufacture phase. This model contains the VNIR and SWIR spectrograph, the VNIR and SWIR detector assemblies with a mechanical cooler for SWIR, signal processing circuit and on-board calibration source.

The Japanese hyper-spectral sensor provides data products covering continuous spectral bands in the wavelength range from 400 nm to 2500 nm. It is characterized by a SNR of > 450 in the VNIR and>300 in the SWIR range at a ground resolution of 30 m x30 m. This report is concerned with the onboard wavelength calibration methods for the Japanese hyper-spectral sensor. As a result of trade study, the combination of a transmission type glass filter containing rare earth oxides, a Mylar polyester film and a quartz tungsten-halogen-lamp was selected. This method covers the wavelength range from 400 nm to 2450 nm. For the purpose of wavelength shift estimation, the method employing the mean square deviation as merit-function was found to be stable and precise. The accuracy of the absorption peak wavelength determination will be expected less than 2% (=0.2 nm) for the VNIR spectral resolution and 5% (=0.625 nm) for the SWIR spectral resolution.

The hyperspectral and the multispectral (hyper-multi spectral) mission is the Japanese next generation space-borne radiometer development project. This project is a heritage from ASTER launched in December 1999. The performance of the hyperspectral radiometer is 30m ground sampling distance, 30km swath width, 10nm and 12.5nm wavelength distance for VNIR and SWIR respectively, over 450@620nm and 300@2,100nm of the signal to noise (S/N) ratio. The performance of the multispectral radiometer is 5m ground sampling distance, 90km swath width, over 200 for all bands of S/N ratio. This project will be launched on ALOS-3 of JAXA in FY2014. The panchromatic sensor with stereo viewing will also be installed on ALOS-3.

The ASTER is a high-resolution optical sensor for observing the Earth on the Terra satellite launched in 1999. The ASTER consists of three radiometers, the VNIR in the visible and near-infrared region, the SWIR in the shortwave infrared region, and the TIR in the thermal infrared region. The on-board calibration devices of the VNIR and the SWIR were two halogen lamps and photodiode monitors. In orbit three bands of the VNIR showed a rapid decrease in the output signal while all SWIR bands remained stable. The TIR has one on-board blackbody and is unable to see the dark space. Therefore the temperature of the on-board blackbody of the TIR remains at 270 K in the short-term calibration for the offset calibration, and is varied from 270 K to 340 K in the long term calibration for the offset and gain calibration. The long term calibration showed a decrease of the TIR response in orbit. The radiometric calibration coefficients of the VNIR and the TIR were fit to smooth functions.

ASTER is a high-resolution optical sensor for observing the Earth on the Terra satellite. ASTER consists of three radiometers, VNIR in the visible and near-infrared region, SWIR in the shortwave infrared region, and TIR in the thermal infrared region. The pre-flight calibration of VNIR and SWIR adopted the working standard large integrating sphere whose radiance levels were traceable to the primary standard fixed-point blackbody. The on-board calibration devices of VNIR and SWIR were two halogen lamps and photodiode monitors. The on-board lamp calibration showed a little shift while launch. In orbit three bands of VNIR showed a rapid decrease in the output signal while all SWIR bands remained stable. The TIR on-board blackbody was calibrated against a standard blackbody from 100 K to 400 K in a vacuum chamber before launch. The TIR is unable to see the dark space. The temperature of the on-board blackbody of TIR remains at 270 K in the short-term calibration for the offset calibration, and is varied from 270 K to 340 K in the long term calibration for the offset and gain calibration. The long term calibration just after launch seemed consistent with the prelaunch calibration but showed a decrease in orbit.