Jupiter and Saturn magnetospheric dynamics explored using auroral electron accelerations derived from ultraviolet auroral emissions

2017 Fiscal Year Annual Research Report

• Project/Area Number: 15K17769
• Research Institution: Tohoku University
• Principal Investigator: 垰 千尋 東北大学, 理学(系)研究科(研究院), 客員研究者 (80552562)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: オーロラ / 木星 / 土星 / 電子加速 / 磁気圏 / ひさき/EXCEED / Juno探査機

Outline of Annual Research Achievements

最終年度において、「ひさき」宇宙望遠鏡の木星オーロラ・スペクトルからのオーロラ電子パラメータ導出方法を適用して、2015年1月の衛星イオ火山活動の活性化に伴うオーロラおよび磁気圏変化を調べた結果を、論文に投稿し、受理された。さらに、このオーロラ観測結果を、Juno探査機搭載のプラズマ計測器による直接その場観測と比較した。両者に相違点を、オーロラの解析で仮定する大気分布の観点から考察し、数値実験による裏づけを行った。これは、極域の大気モデルを制約する意義を持つ。

また、ハッブル宇宙望遠鏡で観測された木星オーロラに、水素原子線と水素分子線の発光強度比(H/H2)によるオーロラ電子エネルギー導出法を適用してエネルギーとフラックス評価を行い、土星オーロラとの相違を比較・考察した結果についても、論文に投稿し受理された。


期間全体を通して、「ひさき」宇宙望遠鏡の木星オーロラ・スペクトルを用いたオーロラ電子パラメータ導出方法を、ハッブル宇宙望遠鏡の観測との比較を通して確立した。さらに、スペクトル情報と加速理論を組み合わせ、磁気圏粒子パラメータ（加速前のプラズマ密度・温度）の変動量を導出した。それらを用いて、木星磁気圏の内因(自転に伴う磁気圏ダイナミクスおよび衛星火山活動)・外因(太陽風)それぞれの変動に対するオーロラ降り込み電子および磁気圏環境の応答を明らかにした。また、オーロラ・スペクトルのH/H2比情報を用いた低エネルギー電子降り込みの解析を、土星に加えて木星にも適用し、惑星間の比較・考察を行った。

Research Products

• [Int'l Joint Research] IRAP/Universite de Toulouse/CNRS/LESIA/Observatoire de Paris/CNRS(フランス)
  • Country Name: FRANCE
  • Counterpart Institution: IRAP/Universite de Toulouse/CNRS/LESIA/Observatoire de Paris/CNRS
• [Int'l Joint Research] Leicester University/Lancaster University(英国)
  • Country Name: UNITED KINGDOM
  • Counterpart Institution: Leicester University/Lancaster University
• [Int'l Joint Research] JPL, California Institute of Technology/Johns Hopkins University/Boston University(米国)
  • Country Name: U.S.A.
  • Counterpart Institution: JPL, California Institute of Technology/Johns Hopkins University/Boston University
  • # of Other Institutions: 1
• [Journal Article] Variation of Jupiter’s Aurora Observed by Hisaki/EXCEED: 3. Volcanic Control of Jupiter's Aurora (2018)
  • Author(s): Tao, C., T. Kimura, F. Tsuchiya, G. Murakami, K. Yoshioka, A. Yamazaki, S. V. Badman, H. Misawa, H. Kita, Y. Kasaba, I. Yoshikawa, and M. Fujimoto
  • Journal Title: Geophys. Res. Lett. Volume: 45 Pages: 71-79
  • DOI: 10.1002/2017GL075814
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Virtual Planetary Space Weather Services offered by the Europlanet H2020 Research Infrastructure (2018)
  • Author(s): N. Andre, M. Grande, N. Achilleos, M. Barthelemy, M. Bouchemit, K. Benson, P.-L. Blelly, E. Budnik, S. Caussarieu, B. Cecconi, T. Cook, V. Genot, P. Guio, ..., C. Tao, et al. (筆頭二者を除いて姓のアルファベット順, 計28名)
  • Journal Title: Planet. Space Sci. Volume: 150 Pages: 50-59
  • DOI: 10.1016/j.pss.2017.04.020
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Response of Jupiter’s aurora to plasma mass loading rate monitored by the Hisaki satellite during volcanic eruptions at Io (2018)
  • Author(s): Kimura, T., Y. Hiraki, C. Tao, F. Tsuchiya, P. A. Delamere, K. Yoshioka, G. Murakami, A. Yamazaki, H. Kita, S. V. Badman, K. Fukazawa, I. Yoshikawa, and M. Fujimoto
  • Journal Title: J. Geophys. Res. Space Physics Volume: 123 Pages: 1-15
  • DOI: 10.1002/2017JA025029
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Auroral electron energy estimation using the H/H2 brightness ratio applied to Jupiter (2017)
  • Author(s): Tao, C., L. Lamy, R. Prange, N. Andre, and S. V. Badman
  • Journal Title: Planetary Radio Emissions VIII Volume: 8 Pages: 139-149
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Independent evolution of stratospheric temperatures in Jupiter's northern and southern auroral regions from 2014 to 2016 (2017)
  • Author(s): Sinclair, J. A., G. S. Orton, T. K. Greathouse, C. Tao, G. R. Gladstone, A. Adriani, W. Dunn, L. N. Fletcher, J. I. Moses, V. Hue, P. G. J. Irwin, H. Melin, and R. S. Giles
  • Journal Title: Geophys. Res. Lett. Volume: 44 Pages: 5345-5354
  • DOI: 10.1002/2017GL073529
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Variability of Jupiter's IR H3+ aurorae during Juno approach (2017)
  • Author(s): Moore, L., J. O'Donoghue, H. Melin, T. Stallard, J. Clarke, M. F. Vogt, B. Zieger, C. Tao, T. Bhakyapaibul, J. E. P. Connerney, S. Levin, and S. Bolton
  • Journal Title: Geophys. Res. Lett. Volume: 44 Pages: 4513-4522
  • DOI: 10.1002/2017GL073156
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Transient brightening of Jupiter's aurora observed by the Hisaki satellite and Hubble Space Telescope during approach phase of the Juno spacecraft (2017)
  • Author(s): Kimura, T., J. D. Nichols, R. L. Gray, C. Tao, G. Murakami, A. Yamazaki, S. V. Badman, F. Tsuchiya, K. Yoshioka, H. Kita, D. Grodent, G. Clark, I. Yoshikawa, and M. Fujimoto
  • Journal Title: Geophys. Res. Lett. Volume: 44 Pages: 4523-4531
  • DOI: 10.1002/2017GL072912
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Response of Jupiter's auroras to conditions in the interplanetary medium as measured by the Hubble Space Telescope and Juno (2017)
  • Author(s): Nichols, J., S. V. Badman, F. Bagenal, S. J. Bolton, B. Bonfond, E. J. Bunce, J. T. Clarke, J. E. P. Connerney, S. W. H. Cowley, R. W. Ebert, ..., C. Tao, et al. (筆頭者を除い て姓のアルファベット順, 計27名)
  • Journal Title: Geophys. Res. Lett. Volume: 44 Pages: 7643-7652
  • DOI: 10.1002/2017GL073029
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Three-year of observations of Jupiter's aurora and Io plasma torus variabilities by earth orbiting extreme-ultraviolet spectroscope HISAKI (2017)
  • Author(s): Tsuchiya, F., K. Yoshioka, T. Kimura, G. Murakami, C. Tao, H. Kita, I. Yoshikawa, A. Yamazaki, and Y. Kasaba
  • Journal Title: J. Physics: Conference Series Volume: 869 Pages: 1-4
  • Peer Reviewed
• [Journal Article] An isolated, bright cusp aurora at Saturn (2017)
  • Author(s): Kinrade, J., S. V. Badman, E. J. Bunce, C. Tao, G. Provan, S. W. H. Cowley, A. Grocott, R. L. Gray, D. Grodent, T. Kimura, J. D. Nichols, C. S. Arridge, A. Radioti, J. T. Clarke, F. J. Crary, W. R. Pryor, H. Melin, K. H. Baines, and M. K. Dougherty
  • Journal Title: J. Geophys. Res. Space Physics Volume: 122 Pages: 6121-6138
  • DOI: 10.1002/2016JA02379
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Volcanic activity on Io and its influence on the dynamics of the Jovian magnetosphere observed by EXCEED/Hisaki in 2015 (2017)
  • Author(s): Yoshikawa, I., F. Suzuki, R. Hikida, K. Yoshioka, G. Murakami, F. Tsuchiya, C. Tao, A. Yamazaki, T. Kimura, H. Kita, H. Nozawa, and M. Fujimoto
  • Journal Title: Earth, Planets and Space--Frontier Letter Volume: 69 Pages: 1-11
  • DOI: 10.1186/s40623-017-0700-9
  • Peer Reviewed / Open Access
• [Journal Article] Characterization of Jupiter's secondary auroral oval and its response to hot plasma injections (2017)
  • Author(s): Gray, R. L., S. V. Badman, E. E. Woodfield, and C. Tao
  • Journal Title: J. Geophys. Res. Space Physics Volume: 122 Pages: 6415-6429
  • DOI: 10.1002/2017JA024214
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] A flux comparison of northern and southern Saturn kilometric radio bursts during southern summer (2017)
  • Author(s): Kasaba, Y., T. Kimura, D. Maruno, A. Morioka, B. Cecconi, L. Lamy, C. M. Jackman, C. Tao, H. Kita, H. Misawa, T. Tsuchiya, and A. Kumamoto
  • Journal Title: Planetary Radio Emissions VIII Volume: 8 Pages: 205-215
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Properties of Jupiter’s magnetospheric turbulence observed by the Galileo spacecraft (2018)
  • Author(s): Tao, C., F. Sahraoui, D. Fontaine, J. de Patoul, T. Chust, S. Kasahara, A. Retino, and E. Kronberg
  • Organizer: Fundamental Physical Processes in Solar-Terrestrial Research and Their Relevance to Planetary Physics 2018
  • Int'l Joint Research / Invited
• [Presentation] ひさきで観測された木星オーロラの周期変動 (2018)
  • Author(s): Tao, C., T. Kimura, F. Tsuchiya, G. Murakami, K. Yoshioka, A. Yamazaki, H. Kita, I. Yoshikawa, Y. Kasaba, M. Fujimoto
  • Organizer: 惑星圏研究会
• [Presentation] Auroral Electron Energy Estimation Using H/H2 Brightness Ratio Applied to Jupiter (2017)
  • Author(s): 垰 千尋, Lamy Laurent, Prange Renee, Andre Nicolas, Badman Sarah
  • Organizer: JpGU-AGU 2017
  • Int'l Joint Research
• [Presentation] Variation of Jupiter's Auroral Electron Parameters Observed by Hisaki/EXCEED (2017)
  • Author(s): Tao, C., T. Kimura, F. Tsuchiya, G. Murakami, K. Yoshioka, H. Kita, A. Yamazaki, S. V. Badman, N. Andre, Y. Kasaba, I. Yoshikawa, and M. Fujimoto
  • Organizer: Magnetospheres of the Outer Planets (MOP) 2017
  • Int'l Joint Research
• [Presentation] H/H2 Brightness Ratio of Jupiter Aurora (2017)
  • Author(s): Tao, C., L. Lamy, R. Prange, N. Andre, S. V. Badman
  • Organizer: Magnetospheres of the Outer Planets (MOP) 2017
  • Int'l Joint Research
• [Presentation] Periodic variations of Jupiter’s aurora observed by Hisaki (2017)
  • Author(s): Tao, C., T. Kimura, S. V. Badman, N. Andre, F. Tsuchiya, G. Murakami, K. Yoshioka, D. Shiota, H. Tadokoro, I. Yoshikawa, A. Yamazaki, and M. Fujimoto
  • Organizer: ISSI team meeting
  • Int'l Joint Research / Invited
• [Presentation] Variation of Jupiter auroral spectra during Io volcanic events taken by Hisaki/EXCEED (2017)
  • Author(s): Tao, C., T. Kimura, H. Kita, F. Tsuchiya, G. Murakami, K. Yoshioka, S. V. Badman, N. Andre, A. Yamazaki, I. Yoshikawa, Y. Kasaba, and M. Fujimoto
  • Organizer: ISSI team meeting
  • Int'l Joint Research / Invited
• [Presentation] Variation of Jupiter's aurora observed by Hisaki/EXCEED (2017)
  • Author(s): Tao, C., T. Kimura, H. Kita, F. Tsuchiya, G. Murakami, K. Yoshioka, S. V. Badman, N. Andre, A. Yamazaki, I. Yoshikawa, Y. Kasaba, and M. Fujimoto
  • Organizer: Planetary space weather workshop
  • Int'l Joint Research / Invited
• [Presentation] Solar wind: 1D MHD propagation model (2017)
  • Author(s): Tao, C., N. Andre, V. Genot, A. P. Rouillard, E. Budnik, and A. Biegun
  • Organizer: Planetary space weather workshop
  • Int'l Joint Research / Invited
• [Presentation] 磁気圏グローバルモデルを用いた木星オーロラ増光時の磁気圏ダイナミクス (2017)
  • Author(s): 垰 千尋, 深沢 圭一郎, 木村 智樹, 北 元, 土屋 史紀, 村上 豪
  • Organizer: 第142回地球電磁気・地球惑星圏学会