太陽系科学研究系

藤本 正樹

Fujimoto Masaki  (Masaki Fujimoto)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 教授 (副所長)
学位
理学博士(1992年3月 東京大学)

連絡先
fujimoto.masakijaxa.jp
J-GLOBAL ID
200901003508985603
researchmap会員ID
1000203981

2006年より、JAXA宇宙科学研究所に所属。それまでの宇宙プラズマ物理の研究に加え、太陽系探査の企画推進にも関わるように。その立場で貢献してきたものとして、JUICE, ひさき、ERG、はやぶさ2,MMX、DESTINY+。宇宙プラズマ研究において多体系の物理への興味が高かったこと、JAXAが得意とする小天体とのリンクが強いことから、N体計算からの惑星系形成論も研究テーマに追加した。また、太陽系探査以外の宇宙科学計画の国際協力調整にも携わる。


論文

 171
  • Yuichiro Ezoe, Ryu Funase, Harunori Nagata, Yoshizumi Miyoshi, Hiroshi Nakajima, Ikuyuki Mitsuishi, Kumi Ishikawa, Masaki Numazawa, Yosuke Kawabata, Shintaro Nakajima, Ryota Fuse, Ralf C. Boden, Landon Kamps, Tomokage Yoneyama, Kouichi Hagino, Yosuke Matsumoto, Keisuke Hosokawa, Satoshi Kasahara, Junko Hiraga, Kazuhisa Mitsuda, Masaki Fujimoto, Munetaka Ueno, Atsushi Yamazaki, Hiroshi Hasegawa, Takefumi Mitani, Yasuhiro Kawakatsu, Takahiro Iwata, Hiroyuki Koizumi, Hironori Sahara, Yoshiaki Kanamori, Kohei Morishita, Daiki Ishi, Aoto Fukushima, Ayata Inagaki, Yoko Ueda, Hiromi Morishita, Yukine Tsuji, Runa Sekiguchi, Takatoshi Murakawa, Kazuma Yamaguchi, Rei Ishikawa, Daiki Morimoto, Yudai Yamada, Shota Hirai, Yuki Nobuhara, Yownin Albert M. Leung, Yamato Itoigawa, Ryo Onodera, Satoru Kotaki, Shotaro Nakamura, Ayumi Kiuchi, Takuya Matsumoto, Midori Hirota, Kazuto Kashiwakura
    Journal of Astronomical Telescopes, Instruments, and Systems 9(03) 2023年9月12日  
  • Toru Yada, Masanao Abe, Tatsuaki Okada, Aiko Nakato, Kasumi Yogata, Akiko Miyazaki, Kentaro Hatakeda, Kazuya Kumagai, Masahiro Nishimura, Yuya Hitomi, Hiromichi Soejima, Miwa Yoshitake, Ayako Iwamae, Shizuho Furuya, Masayuki Uesugi, Yuzuru Karouji, Tomohiro Usui, Tasuku Hayashi, Daiki Yamamoto, Ryota Fukai, Seiji Sugita, Yuichiro Cho, Koki Yumoto, Yuna Yabe, Jean-Pierre Bibring, Cedric Pilorget, Vincent Hamm, Rosario Brunetto, Lucie Riu, Lionel Lourit, Damien Loizeau, Guillaume Lequertier, Aurelie Moussi-Soffys, Shogo Tachibana, Hirotaka Sawada, Ryuji Okazaki, Yoshinori Takano, Kanako Sakamoto, Yayoi N. Miura, Hajime Yano, Trevor R. Ireland, Tetsuya Yamada, Masaki Fujimoto, Kohei Kitazato, Noriyuki Namiki, Masahiko Arakawa, Naru Hirata, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Hikaru Yabuta, Hiroshi Naraoka, Motoo Ito, Eizo Nakamura, Kentaro Uesugi, Katsura Kobayashi, Tatsuhiro Michikami, Hiroshi Kikuchi, Naoyuki Hirata, Yoshiaki Ishihara, Koji Matsumoto, Hirotomo Noda, Rina Noguchi, Yuri Shimaki, Kei Shirai, Kazunori Ogawa, Koji Wada, Hiroki Senshu, Yukio Yamamoto, Tomokatsu Morota, Rie Honda, Chikatoshi Honda, Yasuhiro Yokota, Moe Matsuoka, Naoya Sakatani, Eri Tatsumi, Akira Miura, Manabu Yamada, Atsushi Fujii, Chikako Hirose, Satoshi Hosoda, Hitoshi Ikeda, Takahiro Iwata, Shota Kikuchi, Yuya Mimasu, Osamu Mori, Naoko Ogawa, Go Ono, Takanobu Shimada, Stefania Soldini, Tadateru Takahashi, Yuto Takei, Hiroshi Takeuchi, Ryudo Tsukizaki, Kent Yoshikawa, Fuyuto Terui, Satoru Nakazawa, Satoshi Tanaka, Takanao Saiki, Makoto Yoshikawa, Sei-ichiro Watanabe, Yuichi Tsuda
    NATURE ASTRONOMY 6(2) 214-+ 2022年2月  
    Abstract C-type asteroids1 are considered to be primitive small Solar System bodies enriched in water and organics, providing clues to the origin and evolution of the Solar System and the building blocks of life. C-type asteroid 162173 Ryugu has been characterized by remote sensing2–7 and on-asteroid measurements8,9 with Hayabusa2 (ref. 10). However, the ground truth provided by laboratory analysis of returned samples is invaluable to determine the fine properties of asteroids and other planetary bodies. We report preliminary results of analyses on returned samples from Ryugu of the particle size distribution, density and porosity, spectral properties and textural properties, and the results of a search for Ca–Al-rich inclusions (CAIs) and chondrules. The bulk sample mainly consists of rugged and smooth particles of millimetre to submillimetre size, confirming that the physical and chemical properties were not altered during the return from the asteroid. The power index of its size distribution is shallower than that of the surface boulder observed on Ryugu11, indicating differences in the returned Ryugu samples. The average of the estimated bulk densities of Ryugu sample particles is 1,282 ± 231 kg m−3, which is lower than that of meteorites12, suggesting a high microporosity down to the millimetre scale, extending centimetre-scale estimates from thermal measurements5,9. The extremely dark optical to near-infrared reflectance and spectral profile with weak absorptions at 2.7 and 3.4 μm imply a carbonaceous composition with indigenous aqueous alteration, matching the global average of Ryugu3,4 and confirming that the sample is representative of the asteroid. Together with the absence of submillimetre CAIs and chondrules, these features indicate that Ryugu is most similar to CI chondrites but has lower albedo, higher porosity and more fragile characteristics.
  • Yoshifumi Saito, Dominique Delcourt, Masafumi Hirahara, Stas Barabash, Nicolas André, Takeshi Takashima, Kazushi Asamura, Shoichiro Yokota, Martin Wieser, Masaki N. Nishino, Mitsuo Oka, Yoshifumi Futaana, Yuki Harada, Jean-André Sauvaud, Philippe Louarn, Benoit Lavraud, Vincent Génot, Christian Mazelle, Iannis Dandouras, Christian Jacquey, Claude Aoustin, Alain Barthe, Alexandre Cadu, Andréi Fedorov, Anne-Marie Frezoul, Catherine Garat, Eric Le Comte, Qiu-Mei Lee, Jean-Louis Médale, David Moirin, Emmanuel Penou, Mathieu Petiot, Guy Peyre, Jean Rouzaud, Henry-Claude Séran, Zdenĕk Nĕmec̆ek, Jana S̆afránková, Maria Federica Marcucci, Roberto Bruno, Giuseppe Consolini, Wataru Miyake, Iku Shinohara, Hiroshi Hasegawa, Kanako Seki, Andrew J. Coates, Frédéric Leblanc, Christophe Verdeil, Bruno Katra, Dominique Fontaine, Jean-Marie Illiano, Jean-Jacques Berthelier, Jean-Denis Techer, Markus Fraenz, Henning Fischer, Norbert Krupp, Joachim Woch, Ulrich Bührke, Björn Fiethe, Harald Michalik, Haruhisa Matsumoto, Tomoki Yanagimachi, Yoshizumi Miyoshi, Takefumi Mitani, Manabu Shimoyama, Qiugang Zong, Peter Wurz, Herman Andersson, Stefan Karlsson, Mats Holmström, Yoichi Kazama, Wing-Huen Ip, Masahiro Hoshino, Masaki Fujimoto, Naoki Terada, Kunihiro Keika
    Space Science Reviews 217(5) 2021年8月  
  • Yuichiro Ezoe, Ryu Funase, Harunori Nagata, Yoshizumi Miyoshi, Satoshi Kasahara, Hiroshi Nakajima, Ikuyuki Mitsuishi, Kumi Ishikawa, Junko S. Hiraga, Kazuhisa Mitsuda, Masaki Fujimoto, Munetaka Ueno, Atsushi Yamazaki, Hiroshi Hasegawa, Yosuke Matsumoto, Yasuhiro Kawakatsu, Takahiro Iwata, Hironori Sahara, Yoshiaki Kanamori, Kohei Morishita, Hiroyuki Koizumi, Makoto Mita, Takefumi Mitani, Masaki Numazawa, Landon Kamps, Yusuke Kawabata
    SPACE TELESCOPES AND INSTRUMENTATION 2020: ULTRAVIOLET TO GAMMA RAY 11444 2021年  
    GEO-X (GEOspace X-ray imager) is a 50 kg-class small satellite to image the global Earth's magnetosphere in X-rays via solar wind charge exchange emission. A 12U CubeSat will be injected into an elliptical orbit with an apogee distance of similar to 40 Earth radii. In order to observe the diffuse soft X-ray emission in 0.3-2 keV and to verify X-ray imaging of the dayside structures of the magnetosphere such as cusps, magnetosheaths and magnetopauses which are identified statistically by in-situ satellite observations, an original light-weight X-ray imaging spectrometer (similar to 10 kg, similar to 10 W, similar to 10x10x30 cm) will be carried. The payload is composed of a ultra light-weight MEMS Wolter type-I telescope (similar to 4x4 deg(2) FOV, <10 arcmin resolution) and a high speed CMOS sensor with a thin optical blocking filter (similar to 2x2 cm(2), frame rate similar to 20 ms, energy resolution <80 eV FWHM at 0.6 keV). An aimed launch year is 2023-25 corresponding to the 25th solar maximum.
  • Go Murakami, Hajime Hayakawa, Hiroyuki Ogawa, Shoya Matsuda, Taeko Seki, Yasumasa Kasaba, Yoshifumi Saito, Ichiro Yoshikawa, Masanori Kobayashi, Wolfgang Baumjohann, Ayako Matsuoka, Hirotsugu Kojima, Satoshi Yagitani, Michel Moncuquet, Jan-Erik Wahlund, Dominique Delcourt, Masafumi Hirahara, Stas Barabash, Oleg Korablev, Masaki Fujimoto
    Space Science Reviews 216(7) 2020年10月  

MISC

 108
  • 倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BARUCCI Maria Antonella, LAWRENCE David J., 玄田英典, 平田成, 今村剛, 亀田真吾, 小林正規, 草野広樹, 松本晃治, MICHEL Patrick, 宮本英昭, 中川広務, 中村智樹, 小川和律, 小川和律, 大嶽久志, 尾崎正伸, RUSSEL Sara, 佐々木晶, 澤田弘崇, 千秋博紀, 寺田直樹, ULAMEC Stephan, 臼井寛裕, 和田浩二, 横田勝一郎
    日本惑星科学会秋季講演会予稿集(Web) 2020 2020年  
  • 江副祐一郎, 三好由純, 笠原慧, 船瀬龍, 石川久美, 山崎敦, 長谷川洋, 木村智樹, 松本洋介, 藤本正樹, 上野宗孝, 川勝康弘, 岩田隆浩
    地球電磁気・地球惑星圏学会総会及び講演会(Web) 146th 2019年  
  • Ronald-Louis Ballouz, Nicola Baresi, Sarah T. Crites, Yasuhiro Kawakatsu, Masaki Fujimoto
    2018年9月7日  
    The surface of the Martian moon Phobos exhibits two distinct geologic units, known as the red and blue units. The provenance of these regions is uncertain yet crucial to understanding the origin of the Martian moon and its interaction with the space environment. Here we show that Phobos' orbital eccentricity can cause sufficient grain motion to refresh its surface, suggesting that space weathering is the likely driver of the dichotomy on the moon's surface. In particular, we predict that blue regions are made up of pristine endogenic material that can be uncovered in steep terrain subject to large variations in the tidal forcing from Mars. The predictions of our model are consistent with current spacecraft observations which show that blue units are found near these regions.
  • 矢田達, 安部正真, 岡田達明, 坂本佳奈子, 吉武美和, 中埜夕希, 松本徹, 川崎教行, 熊谷和也, 西村征洋, 松井重雄, 圦本尚義, 圦本尚義, 藤本正樹, 藤本正樹
    日本地球惑星科学連合大会予稿集(Web) 2018 2018年  
  • T. Yada, K. Sakamoto, M. Yoshitake, Y. Nakano, K. Kumagai, M. Nishimura, S. Matsui, T. Matsumoto, N. Kawasaki, T. Okada, M. Abe, H. Yurimoto, M. Fujimoto
    METEORITICS & PLANETARY SCIENCE 52 A393-A393 2017年8月  

共同研究・競争的資金等の研究課題

 25

学術貢献活動

 3