Spectral data analysis of the asteroid Itokawa based on high resolution shape models

• Project/Area Number: 17K05639
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Aizu
• Principal Investigator: Hirata Naru 会津大学, コンピュータ理工学部, 上級准教授 (80372655)
• Co-Investigator(Kenkyū-buntansha): 出村 裕英 会津大学, コンピュータ理工学部, 教授 (10360009) ; 北里 宏平 会津大学, コンピュータ理工学部, 准教授 (50550597)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 小惑星 / イトカワ / はやぶさ / 地理情報システム / リュウグウ / はやぶさ2 / 分光 / 形状モデル / 惑星探査 / 惑星起源・進化

Outline of Final Research Achievements

By combining a high-precision shape models with spectroscopic observation data of of asteroids Itokawa and Ryugu, the distribution and regional differences on the surface of the asteroid and geological activity on the asteroid and its parent body are revealed. The asteroid Itokawa has a fresh region with less space-weathered in the Neck region. This area is characterized with severe diurnal variations in surface temperature and very steep slopes. This suggests that the environment may be one in which the weathering rate does not increase due to the constant renewal of the surface layer. The surface material of the asteroid Ryugu is strongly weathered and suffered by a heavy dehydration process.

Academic Significance and Societal Importance of the Research Achievements

小惑星探査機はやぶさとはやぶさ2によって取得されたデータを駆使して，小惑星ItokawaとRyuguの構成物質を明らかにした上，小惑星表面の地質活動や両者の母天体の描像にも迫る情報を得ることができた．特に，近年小惑星上で起きる現象として着目されている熱疲労が，Itokawaでも重要な表面更新機構である可能性を見出した点は重要な知見である．また，終了したミッションのアーカイブデータから新たな知見を引き出せたこと，また進行中のミッションで取得されたデータから迅速な成果を得ることができたこと，いずれもビッグサイエンスである月惑星探査の成果を最大化するという観点からも大きな意義があったと考えられる．

Research Products

• [Int'l Joint Research] Applied Physics Laboratory(米国)
• [Int'l Joint Research] Applied Physics Laboratory(米国)
• [Int'l Joint Research] Applied Physics Laboratory(米国)
• [Journal Article] A generalised methodology for analytic construction of 1:1 resonances around irregular bodies: Application to the asteroid Ryugu’s ejecta dynamics (2020)
  • Author(s): Soldini Stefania、Takanao Saiki、Ikeda Hitoshi、Wada Koji、Yuichi Tsuda、Hirata Naru、Hirata Naoyuki
  • Journal Title: Planetary and Space Science Volume: 180 Pages: 104740-104740
  • DOI: 10.1016/j.pss.2019.104740
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The spatial distribution of impact craters on Ryugu (2020)
  • Author(s): Hirata Naoyuki、Morota Tomokatsu、Cho Yuichiro、Kanamaru Masanori、Watanabe Sei-ichiro、Sugita Seiji、Hirata Naru、Yamamoto Yukio、Noguchi Rina、Shimaki Yuri、Tatsumi Eri、Yoshioka Kazuo、Sawada Hirotaka、Yokota Yasuhiro、Sakatani Naoya、Hayakawa Masahiko、Matsuoka Moe、Honda Rie、Kameda Shingo
  • Journal Title: Icarus Volume: 338 Pages: 113527-113527
  • DOI: 10.1016/j.icarus.2019.113527
  • NAID: 120006766134
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Improving Hayabusa2 trajectory by combining LIDAR data and a shape model (2020)
  • Author(s): Matsumoto, K., Noda, H., Ishihara, Y., Senshu, H., Yamamoto, K., Hirata, N., Hirata, N., Namiki, N., Otsubo, T., Higuchi, A., Watanabe, S., Ikeda, H., Mizuno, T., Yamada, R., Araki, H., Abe, S., Yoshida, F., Sasaki, S., et al
  • Journal Title: Icarus Volume: 338 Pages: 113574-113574
  • DOI: 10.1016/j.icarus.2019.113574
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Highly porous nature of a primitive asteroid revealed by thermal imaging (2020)
  • Author(s): T.Okada, T.Fukuhara, S.Tanaka, M.Taguchi, T.Arai, H.Senshu, N.Sakatani, Y.Shimaki, H.Demura, Y.Ogawa, K.Suko, T.Sekiguchi, T.Kouyama, J.Takita, T.Matsunaga, T.Imamura, T.Wada, S.Hasegawa, J.Helbert, T.G.Muller, A.Hagermann, J.Biele, M.Grott, M.Hamm, M.Delbo, N.Hirata, N.Hirata, Y.Yamamoto, A.Miura, et al.
  • Journal Title: Nature Volume: 579 Issue: 7800 Pages: 518-522
  • DOI: 10.1038/s41586-020-2102-6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Dynamic precise orbit determination of Hayabusa2 using laser altimeter (LIDAR) and image tracking data sets (2020)
  • Author(s): Yamamoto, K., Otsubo, T., Matsumoto, K., Noda, H., Namiki, N., Takeuchi, H., Ikeda, H., Yoshikawa, M., Yamamoto, Y., Senshu, H., Mizuno, T., Hirata, N. et al.
  • Journal Title: Earth, Planets and Space Volume: 72 Issue: 1 Pages: 85-85
  • DOI: 10.1186/s40623-020-01213-2
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Sample collection from asteroid (162173) Ryugu by Hayabusa2: Implications for surface evolution (2020)
  • Author(s): Morota, T., Sugita, S., Cho, Y., Kanamaru, M., Tatsumi, E., Sakatani, N., Honda, R., Hirata, N. et al.
  • Journal Title: Science Volume: 368 Issue: 6491 Pages: 654-659
  • DOI: 10.1126/science.aaz6306
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] An artificial impact on the asteroid 162173 Ryugu formed a crater in the gravity-dominated regime (2020)
  • Author(s): Arakawa, M., Saiki, T., Wada, K., Ogawa, K., Kadono, T., Shirai, K., Sawada, H., Ishibashi, K., Honda, R., Sakatani, N., Iijima, Y., Okamoto, C., Yano, H., Takagi, Y., Hayakawa, M., Michel, P., Jutzi, M., Shimaki, Y., Kimura, S., Mimasu, Y., Toda, T., Imamura, H., Nakazawa, S., Hayakawa, H., Sugita, S., et al.
  • Journal Title: Science Volume: 368 Issue: 6486 Pages: 67-71
  • DOI: 10.1126/science.aaz1701
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Boulder size and shape distributions on asteroid Ryugu (2019)
  • Author(s): Michikami Tatsuhiro、Honda Chikatoshi、Miyamoto Hideaki、Hirabayashi Masatoshi、Hagermann Axel、Irie Terunori、Nomura Keita、Ernst Carolyn M.、et al.
  • Journal Title: Icarus Volume: 331 Pages: 179-191
  • DOI: 10.1016/j.icarus.2019.05.019
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Multivariable statistical analysis of spectrophotometry and spectra of (162173) Ryugu as observed by JAXA Hayabusa2 mission (2019)
  • Author(s): Barucci M. A.、Hasselmann P. H.、Fulchignoni M.、Honda R.、Yokota Y.、Sugita S.、Kitazato K.、Deshapriya J. D. P.、Perna D.、Tatsumi E.、Domingue D.、Morota T.、Kameda S.、Iwata T.、Abe M. et al.
  • Journal Title: Astronomy & Astrophysics Volume: 629 Pages: A13-A13
  • DOI: 10.1051/0004-6361/201935851
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Hayabusa2 arrives at the carbonaceous asteroid 162173 Ryugu?A spinning top?shaped rubble pile (2019)
  • Author(s): Watanabe S.、Hirabayashi M.、Hirata N. et al.
  • Journal Title: Science Volume: 364 Issue: 6437 Pages: 268-272
  • DOI: 10.1126/science.aav8032
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The geomorphology, color, and thermal properties of Ryugu: Implications for parent-body processes (2019)
  • Author(s): Seiji Sugita, R. Honda, T. Morota, S. Kameda, H. Sawada, E. Tatsumi, M. Yamada, C. Honda, Y. Yokota, T. Kouyama, N. Sakatani, K. Ogawa, H. Suzuki, T. Okada, N. Namiki, S. Tanaka, Y. Iijima, K. Yoshioka, M. Hayakawa, Y. Cho, M. Matsuoka, N. Hirata, N. Hirata, H. Miyamoto, Jun Kimura
  • Journal Title: Science Volume: 17 Issue: 6437 Pages: 252-252
  • DOI: 10.1126/science.aaw0422
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] The surface composition of asteroid 162173 Ryugu from Hayabusa2 near-infrared spectroscopy (2019)
  • Author(s): Kitazato K. et al.
  • Journal Title: Science Volume: 364 Issue: 6437 Pages: 272-275
  • DOI: 10.1126/science.aav7432
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Shape of (101955) Bennu indicative of a rubble pile with internal stiffness (2019)
  • Author(s): Barnouin O. S.、The OSIRIS-REx Team et al.
  • Journal Title: Nature Geoscience Volume: 12 Issue: 4 Pages: 247-252
  • DOI: 10.1038/s41561-019-0330-x
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The Western Bulge of 162173 Ryugu Formed as a Result of a Rotationally Driven Deformation Process (2019)
  • Author(s): Hirabayashi M.、Tatsumi E.、Miyamoto H.、Komatsu G.、Sugita S.、Watanabe S.、Scheeres D. J.、Barnouin O. S.、Michel P.、Honda C.、Michikami T.、Cho Y.、Morota T.、Hirata N. et al.
  • Journal Title: The Astrophysical Journal Volume: 874 Issue: 1 Pages: L10-L10
  • DOI: 10.3847/2041-8213/ab0e8b
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Vis-NIR disk-integrated photometry of asteroid 25143 Itokawa around opposition by AMICA/Hayabusa (2018)
  • Author(s): Tatsumi Eri、Domingue Deborah、Hirata Naru、Kitazato Kohei、Vilas Faith、Lederer Susan、Weissman Paul R.、Lowry Stephen C.、Sugita Seiji
  • Journal Title: Icarus Volume: 311 Pages: 175-196
  • DOI: 10.1016/j.icarus.2018.04.001
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] HARMONICS: A Visualization Tool for <i>Hayabusa</i> and <i>Hayabusa 2</i> Missions (2017)
  • Author(s): Wataru UENO, Hirohide DEMURA, Naru HIRATA
  • Journal Title: TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES Volume: 60 Issue: 3 Pages: 132-136
  • DOI: 10.2322/tjsass.60.132
  • NAID: 130005635921
  • ISSN: 0549-3811, 2189-4205
  • Peer Reviewed
• [Presentation] Shape Reconstruction of the Asteroid Ryugu with Structure-from-Motion Method (2020)
  • Author(s): Hirata, N. Sugiyama, T. Hirata, N. Tanaka, S. Nishikawa, N. Noguchi, R. Shimaki, Y. Gaskell, R. Palmer, E. Matsumoto, K. Senshu, H. Yamamoto, Y. Murakami, S. Ishihara, Y. Sugita, S. Morota, T. Honda, R. Arakawa, M. Ogawa, K. Tsuda, Y. Watanabe, S.
  • Organizer: 51st Lunar and Planetary Science Conference
  • Int'l Joint Research
• [Presentation] New Features of AiGIS: A 3D-GIS for Visualization of Map and Shape of Irregular-Shaped Small Bodies (2019)
  • Author(s): Hirata, N.、Demura, H.、Tsuchiya, T.、Yamaguchi, Y.、Endo, T.、Sato, H.、Otake, H.
  • Organizer: 50th Lunar and Planetary Science
  • Int'l Joint Research
• [Presentation] Regolith Properties on the S-Type Asteroid Itokawa Estimated from Photometrical Measurements (2018)
  • Author(s): Tatsumi, E. Domingue, D. Hirata, N. Kitazato, K. and Vilas, F. Lederer, S. M. Weissman, P. R. Lowrys, S.C. and Sugita, S.
  • Organizer: Lunar and Planetary Science Conference
  • Int'l Joint Research
• [Presentation] AiGIS: A 3D-GIS for Visualization of Map and Shape of Irregular-Shaped Small Bodies (2018)
  • Author(s): Hirata, N. Demura, H. Ichikawa, M. Endo, T. and Ishihara, Y. Sato, H. Otake, H.
  • Organizer: Lunar and Planetary Science Conference
  • Int'l Joint Research
• [Presentation] GUI Retrieval of FOVs in HARMONICS for 2018 Rendezvous of Hayabusa2 (2018)
  • Author(s): Aoki, Y. Demura, H. Hirata, N. Ichikawa, M. and Endo, T.
  • Organizer: Lunar and Planetary Science Conference
  • Int'l Joint Research
• [Presentation] Constraints on global distribution of regolith deposits on the asteroid 162173 Ryugu (2017)
  • Author(s): Hirata, Naru Matsumoto, K Michikami, T Kimura, J
  • Organizer: JpGU-AGU Joint Meeting
  • Int'l Joint Research
• [Presentation] 小惑星イトカワの表面に見られる白色地域の成因 (2017)
  • Author(s): 北里宏平, 平田成, 出村裕英, 稲澤朋生, 安部正真, 山本幸生, 三浦昭, 川口淳一郎
  • Organizer: 日本惑星科学会2017年秋季講演会
• [Presentation] Thermally induced rock breakdown on asteroid Itokawa (2017)
  • Author(s): Kitazato, K., Hirata, N., Demura, H., Inasawa, T., Abe, M., Yamamoto, Y., Miura A., Kawaguchi, J.
  • Organizer: American Astronomical Society, DPS meeting #49
  • Int'l Joint Research
• [Presentation] Cluster analysis of near-infrared reflectance spectra of asteroid Itokawa (2017)
  • Author(s): Inasawa, T., Kitazato, K., Hirata, N., Demura, H.
  • Organizer: American Astronomical Society, DPS meeting #49
  • Int'l Joint Research
• [Remarks] ARC-Space
  • URL: https://arcspace.jp/
• [Remarks] Hayabusa2 Science Data Archives
  • URL: http://darts.isas.jaxa.jp/planet/project/hayabusa2/