Microscale processes in the Venus atmosphere revealed by radio occultation

• Project/Area Number: 24540482
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Space and upper atmospheric physics
• Research Institution: Japan Aerospace Exploration Agency
• Principal Investigator: IMAMURA Takeshi 独立行政法人宇宙航空研究開発機構, 宇宙科学研究所, 准教授 (40311170)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2012: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 電波掩蔽 / 電波ホログラフィ / Full Spectral Inversion / 金星大気 / 惑星大気 / 金星 / ホログラフィ / Full Spectrum Inversion

Outline of Final Research Achievements

In the previous radio occultation observations, geometrical optics method has been used for retrieving refractive index profiles from measured phase time series, and multipath effect and diffraction effect prevented us from obtaining detailed atmospheric structures. We applied a radio holographic analysis to radio occultation data of Venusian atmosphere to solve these problems, and successfully revealed fine structures related to gravity waves and inversion layers.

Research Products

• [Journal Article] Vertical wavenumber spectra of gravity waves in the Venus atmosphere obtained from Venus Express radio occultation data: evidence for saturation (2015)
  • Author(s): Ando, H., T. Imamura, T. Tsuda, S. Tellmann, M. Pätzold and B. Häusler
  • Journal Title: Journal of the Atmospheric Sciences Volume: 印刷中 Issue: 6 Pages: 2318-2329
  • DOI: 10.1175/jas-d-14-0315.1
  • Peer Reviewed
• [Journal Article] Outflow structure of the quiet Sun corona probed by spacecraft radio scintillations in strong scattering (2014)
  • Author(s): 57.Imamura, T., M. Tokumaru, H. Isobe, D. Shiota, H. Ando, M. Miyamoto, T. Toda, B. Häusler, M. Pätzold, A. Nabatov, A. Asai, K. Yaji, M. Yamada, M. Nakamura
  • Journal Title: The Astrophysical Journal Volume: 788 Issue: 2 Pages: 117-117
  • DOI: 10.1088/0004-637x/788/2/117
  • Peer Reviewed / Open Access
• [Journal Article] Inverse insolation dependence of Venus' cloud-level convection (2014)
  • Author(s): Imamura, T., T. Higuchi, Y. Maejima, M. Takagi, N. Sugimoto, K. Ikeda, and H. Ando
  • Journal Title: Icarus Volume: 228 Pages: 181-188
  • DOI: 10.1016/j.icarus.2013.10.012
  • Peer Reviewed
• [Journal Article] Outflow structure of the quiet Sun corona probed by spacecraft radio scintillations in strong scattering (2014)
  • Author(s): Imamura, T., M. Tokumaru, H. Isobe, D. Shiota, H. Ando, M. Miyamoto, T. Toda, B. Häusler, M. Pätzold, A. Nabatov, A. Asai, K. Yaji, M. Yamada, M. Nakamura
  • Journal Title: Astrophys. J. Volume: 印刷中
  • Peer Reviewed
• [Journal Article] Dual-spacecraft radio occultation measurement of the electron density near the lunar surface by the SELENE mission (2012)
  • Author(s): H. Ando, T. Imamura, A. Nabatov, Y. Futaana, T. Iwata, H. Handa, K. Matsumoto, N. Mochizuki, Y. Kono, H. Noda, Q. Liu, K. Oyama, Z. Yamamoto, A. Saito
  • Journal Title: J. Geophys. Res. Volume: 117 Issue: A6
  • DOI: 10.1029/2011ja017293
  • Peer Reviewed
• [Journal Article] Vertical wavenumber spectra of gravity waves obtained in Mars Global Surveyor radio occultation data (2012)
  • Author(s): H. Ando, T. Imamura and T. Tsuda
  • Journal Title: J. Atmos. Sci. Volume: 69 Issue: 9 Pages: 2906-2912
  • DOI: 10.1175/jas-d-11-0339.1
  • Peer Reviewed
• [Journal Article] Small-scale temperature fluctuations seen by the VeRa Radio Science Experiment on Venus Express (2012)
  • Author(s): Tellmann, S., B. Haeusler, D. P. Hinson, G. L. Tyler, T. P. Andert, M. K. Bird, T. Imamura, M. Paetzold, and S. Remus
  • Journal Title: Icarus Volume: 221 Issue: 2 Pages: 471-480
  • DOI: 10.1016/j.icarus.2012.08.023
  • Peer Reviewed
• [Presentation] 波ホログラフィ法による金星大気の電波掩蔽データの解析 (2014)
  • Author(s): 宮本 麻由, 今村 剛, 安藤 紘基, 津田 敏隆､青山 雄一
  • Organizer: 地球電磁気・地球惑星圏学会 第１３６回総会及び講演会
  • Place of Presentation: キッセイ文化ホール(長野県松本文化会館)
  • Year and Date: 2014-10-31 – 2014-11-03
• [Presentation] あかつき電波シンチレーション観測による太陽近傍の太陽風速度 (2013)
  • Author(s): 今村剛, 徳丸宗利, 安藤紘基, 磯部洋明, 浅井歩, 塩田大幸, 宮本麻由, 矢治健太郎
  • Organizer: Japan Geoscience Union Meeting 2013
  • Place of Presentation: 幕張メッセ
• [Presentation] Full Spectral Inversionによる金星大気電波掩蔽データの解析 (2013)
  • Author(s): 今村剛（ISAS/JAXA）、安藤紘基（東大理）、青山雄一（極地研）、津田敏隆（京大生存圏）
  • Organizer: 第２７回 大気圏シンポジウム
  • Place of Presentation: JAXA宇宙科学研究所