Asteroid Science 2019 (LPI Contrib. No. 2189) 2093.pdf SHAPE RECONSTRUCTION OF THE ASTEROID RYUGU IN HAYABUSA2 MISSION. Naru Hirata1, Naoyuki Hirata2, S. Tanaka2, N. Nishikawa2, T. Sugiyama1, R. Noguchi3, Y. Shimaki3, R. Gaskell4, E. Palmer4, K. Matsumoto5, H. Senshu6, Y. Yamamoto3, S. Murakami3, Y. Ishihara3, 7, S. Sugita8, T. Morota8, R. Honda9, M. Arakawa2, K. Ogawa2, Y. Tsuda3, S. Watanabe10, 1ARC-Space, the University of Aizu (Aizu-Wakamatsu, Fukushima, 965-8580, Japan,
[email protected]), 2Kobe University, 3ISAS/JAXA, 4Planetary Science Institute, 5NAOJ, 6Chiba Institute of Technology, 7NIES, 8University of Tokyo, 9Kochi University, 10Nagoya University. Introduction: The Hayabusa2 spacecraft arrived during initial observation campaigns from 07/2018 to at the asteroid Ryugu in 06/2018 and started its 08/2018. These campaigns include the Box-A (20 km proximity observation to select candidates of landing altitude), Box-B (6.5 km altitude), and Mid-Altitude sites for touchdown operations. The shape of the (5.1 km altitude) observations. Models were then asteroid is one of the most critical information not only revised with data from following various observations, for landing site selection but also for scientific including close-up imaging during decent operations, discussions. high- and low-phase angle observations, and high sub- We successfully reconstructed and updated the spacecraft latitude observations. Because of constraints shape models of Ryugu with images taken by the on the relative position of the spacecraft to the asteroid, optical navigation camera (ONC) onboard the the sub-spacecraft latitude is limited within ±30˚. This spacecraft and relating ancillary data acquired during limitation affects the performance of the shape model proximity observation of the asteroid [1].