Thermal Infrared Imaging Experiments of C-Type Asteroid 162173 Ryugu on Hayabusa2
Thermal Infrared Imaging Experiments of C-Type Asteroid 162173 Ryugu on Hayabusa2
复制标题
隼鸟二号上 C 型小行星 162173 Ryugu 的热红外成像实验
DOI：
10.1007/s11214-016-0286-8
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
Tatsuaki Okada et al.
中科院分区：
文献类型：
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作者：
Genda;H.;Hamano;K. and Abe;Y.;Tatsuaki Okada et al.
隼鸟2号上的热红外成像仪TIR是为了研究C型近地小行星162173 Ryugu的热物理特性而开发的。TIR是隼鸟2号上的遥感科学仪器之一，旨在了解太阳系中一个挥发物丰富的小天体的性质，但它也有重要的使命目标，即提供关于表面物理特性和取样地点选择条件的信息以及评估安全着陆操作。TIR基于从Akatsuki上的长波红外照相机LIR继承的二维非冷却微测辐射热计阵列（Fukuhara等人，2011年）。全内反射成像系统可对8 ~ 12 μm的热红外辐射进行成像，视场为，空间分辨率为。TIR覆盖150 - 460 K的温度范围，包括230 - 420 K的良好校准范围。对于求和图像，温度精度在2K以内或更好，并且对于良好校准的温度范围，每个像素处的相对精度或噪声等效温差（NETD）为0.4K或更低。TIR在快门打开和关闭的情况下拍摄一对图像，对应的暗帧，并通过暗帧减法提供真实的热图像。数据处理涉及多个图像的求和，图像处理包括StarPixel压缩（Hihara等人，2014年），并转移到航天器数字电子（DE）中的数据记录器。我们报告的科学和使命目标的TIR，仪器规格的要求和限制，设计的仪器和飞行前和飞行中的TIR性能，以及它的观测计划在隼鸟2使命。
The thermal infrared imager TIR onboard Hayabusa2 has been developed to investigate thermo-physical properties of C-type, near-Earth asteroid 162173 Ryugu. TIR is one of the remote science instruments on Hayabusa2 designed to understand the nature of a volatile-rich solar system small body, but it also has significant mission objectives to provide information on surface physical properties and conditions for sampling site selection as well as the assessment of safe landing operations. TIR is based on a two-dimensional uncooled micro-bolometer array inherited from the Longwave Infrared Camera LIR on Akatsuki (Fukuhara et al., 2011). TIR takes images of thermal infrared emission in 8 to 12 μm with a field of view ofand a spatial resolution ofper pixel. TIR covers the temperature range from 150 to 460 K, including the well calibrated range from 230 to 420 K. Temperature accuracy is within 2 K or better for summed images, and the relative accuracy or noise equivalent temperature difference (NETD) at each of pixels is 0.4 K or lower for the well-calibrated temperature range. TIR takes a couple of images with shutter open and closed, the corresponding dark frame, and provides a true thermal image by dark frame subtraction. Data processing involves summation of multiple images, image processing including the StarPixel compression (Hihara et al., 2014), and transfer to the data recorder in the spacecraft digital electronics (DE). We report the scientific and mission objectives of TIR, the requirements and constraints for the instrument specifications, the designed instrumentation and the pre-flight and in-flight performances of TIR, as well as its observation plan during the Hayabusa2 mission.