47th Lunar and Planetary Science Conference (2016) 1801.pdf Earth and Moon Observations with TIR onboard Hayabusa2 Spacecraft. T. Arai1, T. Okada1, S. Tanaka1, T. Fukuhara2, H. Demura3, Y. Ogawa3, and Hayabusa2 TIR team, 1Institute of Space and Astronoutical Science, Japan Aerospace Exploration Agency, Sagamihara, 252-8510, JAPAN (
[email protected]), 2 Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Koganei, Tokyo 184-8795, JAPAN. 3Center for Advanced Information Science and Technology, The University of Aizu, Ikki-machi, Aizu- Wakamatsu, Fukushima 965-8580, JAPAN. Introduction: TIR is an infrared thermal imager (Figure 1). The result of the distortion was within 1 onboard the Hayabusa2 spacecraft, which will perform pixel from the image's center to every corner. thermal imaging of C-class asteroid 162173 Ryugu Pinhole images with TIR was apparently the size of (1999 JU3) through in situ observations during the 1/8 pixel in this collimator system, but an actual bo- rendezvous phase from 2018 to 2019. Hayabusa2 car- lometer pixel size was 37 micrometers. TIR was ried out an Earth swing-by on December 3, 2015, and moved to the radial direction in the step of 0.01 de- TIR observed the Earth and the Moon for calibration grees by using a micro-rotary stage and measured the and performance tests. aperture ratio. Insensible areas were found in the cor- The detector of TIR is an uncooled microbolometer ners of pixels. array (320A, NEC Inc.), and the optical system has a germanium triplet lens. TIR is the same design as a long wave infrared camera, LIR, onboard the Akatsuki Venus climate orbiter [1].