Venus cloud structure and origin of UV contrast

• Project/Area Number: 16K17816
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Space and upper atmospheric physics
• Research Institution: Japan Aerospace EXploration Agency
• Principal Investigator: Sato Takao 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, 宇宙航空プロジェクト研究員 (50633509)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2017: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
• Keywords: 金星 / 大気 / 雲 / リモートセンシング / あかつき / 地上望遠鏡観測 / 惑星探査

Outline of Final Research Achievements

The cloud top altitude of Venus was deduced from images taken by the 2.02-micron channel of 2-micron Camera onboard Japanese Venus orbiter, Akatsuki with the aid of radiative transfer calculation. The latitudinal variation of the cloud top altitude was evaluated quantitatively. The stationary features first discovered by Longwave Infrared Camera onboard Akatsuki were also characterized (e.g., occurrence region and local solar time dependence) with the 2.02-micron images. The coordinated observations of Venus cloud top with Akatsuki and　Subaru Telescope were carried out and the existence of stationary feature was confirmed by Subaru Telescope.

Research Products

• [Journal Article] Initial products of Akatsuki 1-μm camera (2018)
  • Author(s): Iwagami N., Sakanoi T., Hashimoto G., Sawai K., Ohtsuki S., Takagi S., Uemizu K., Ueno M., Kameda S., Murakami S., Nakamura M., Ishii N., Abe T., Satoh T., Imamura T., Hirose C., Suzuki M., Hirata N., Yamazaki A., Sato T., Yamada M., Yamamoto Y., Fukuhara T., Ogohara K., Ando H., Sugiyama K., Kashimura H., Kouyama, T.
  • Journal Title: Earth, Planets and Space Volume: 70 Issue: 1
  • DOI: 10.1186/s40623-017-0773-5
  • NAID: 120006486824
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Ultraviolet imager on Venus orbiter Akatsuki and its initial results (2018)
  • Author(s): Yamazaki, A. et al. (Sato, T.M., 26名中10番目)
  • Journal Title: Earth, Planets and Space Volume: 70 Issue: 1
  • DOI: 10.1186/s40623-017-0772-6
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Venus looks different from day to night across wavelengths: morphology from Akatsuki multispectral images (2018)
  • Author(s): Sanjay S. Limaye, Shigeto Watanabe, Atsushi Yamazaki, Manabu Yamada, Takehiko Satoh, Masato Nakamura, Makoto Taguchi, Tetsuya Fukuhara, Takeshi Imamura, Toru Kouyama, Yeon Joo Lee, Takeshi Horinouchi, Javier Peralta, Naomoto Iwagami, George L. Hashimoto, Seiko Takagi, Shoko Ohtsuki, Shin-ya Murakami et al.
  • Journal Title: Earth, Planets and Space Volume: 70 Issue: 1 Pages: 1-38
  • DOI: 10.1186/s40623-018-0789-5
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Scattering Properties of the Venusian Clouds Observed by the UV Imager on board Akatsuki (2017)
  • Author(s): Lee, Y. J., A. Yamazaki, T. Imamura, M. Yamada, S. Watanabe, T. M. Sato, K. Ogohara, G. L. Hashimoto, and S. Murakami
  • Journal Title: Astronom. J. Volume: 154:44 Issue: 2 Pages: 1-16
  • DOI: 10.3847/1538-3881/aa78a5
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Stationary waves and slowly moving features in the night upper clouds of Venus (2017)
  • Author(s): Peralta, J., Hueso, R., Sanchez-Lavega, A., Lee, Y.J., Garcia-Munoz, A., Kouyama, T., Sagawa, H., Sato, T.M., Piccioni, G., Tellmann, S., Imamura, T., Satoh, T.
  • Journal Title: Nature Astronomy Volume: 1 Issue: 8 Pages: 0187-0187
  • DOI: 10.1038/s41550-017-0187
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Equatorial jet in the lower to middle cloud layer of Venus revealed by Akatsuki (2017)
  • Author(s): Horinouchi Takeshi、Murakami Shin-ya、Satoh Takehiko、Peralta Javier、Ogohara Kazunori、Kouyama Toru、Imamura Takeshi、Kashimura Hiroki、Limaye Sanjay S.、McGouldrick Kevin、Nakamura Masato、Sato Takao M.、Sugiyama Ko-ichiro、Takagi Masahiro、Watanabe Shigeto、Yamada Manabu、Yamazaki Atsushi、Young Eliot F.
  • Journal Title: Nature Geoscience Volume: 10 Issue: 9 Pages: 646-651
  • DOI: 10.1038/ngeo3016
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Initial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki (2017)
  • Author(s): Takeshi Imamura, Hiroki Ando, Silvia Tellmann, Martin Patzold, Bernd Hausler, Atsushi Yamazaki, Takao M. Sato, Katsuyuki Noguchi, Yoshifumi Futaana, Janusz Oschlisniok, Sanjay Limaye, R. K. Choudhary, Takumi Abe and Masato Nakamura
  • Journal Title: Earth, Planets and Space Volume: 69:137 Issue: 1 Pages: 1-11
  • DOI: 10.1186/s40623-017-0722-3
  • NAID: 120006486821
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Absolute calibration of brightness temperature of the Venus disk observed by the Longwave Infrared Camera onboard Akatsuki (2017)
  • Author(s): Tetsuya Fukuhara, Makoto Taguchi, Takeshi Imamura, Akane Hayashitani, Takeru Yamada, Masahiko Futaguchi, Toru Kouyama, Takao M. Sato, Mao Takamura, Naomoto Iwagami, Masato Nakamura, Makoto Suzuki, Munetaka Ueno, George L. Hashimoto, Mitsuteru Sato, Seiko Takagi
  • Journal Title: Earth, Planets and Space Volume: 69:141 Issue: 1 Pages: 1-9
  • DOI: 10.1186/s40623-017-0727-y
  • NAID: 120006486822
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Performance of Akatsuki/IR2 in Venus orbit: the first year (2017)
  • Author(s): Takehiko Satoh, Takao M. Sato, Masato Nakamura, Yasumasa Kasaba, Munetaka Ueno, Makoto Suzuki, George L. Hashimoto, Takeshi Horinouchi, Takeshi Imamura, Atsushi Yamazaki, Takayuki Enomoto, Yuri Sakurai, Kosuke Takami, Kenta Sawai, Takashi Nakakushi, Takumi Abe
  • Journal Title: Earth, Planets and Space Volume: 69:154 Issue: 1 Pages: 1-19
  • DOI: 10.1186/s40623-017-0736-x
  • NAID: 120006486823
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Overview of Akatsuki data products: definition of data levels, method and accuracy of geometric correction (2017)
  • Author(s): Ogohara, K., M. Takagi, et al.
  • Journal Title: Earth, Planets and Space Volume: 69 Issue: 1 Pages: 1-16
  • DOI: 10.1186/s40623-017-0749-5
  • NAID: 120006486825
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Topographical and Local Time Dependence of Large Stationary Gravity Waves Observed at the Cloud Top of Venus (2017)
  • Author(s): Kouyama T.、Imamura T.、Taguchi M.、Fukuhara T.、Sato T. M.、Yamazaki A.、Futaguchi M.、Murakami S.、Hashimoto G. L.、Ueno M.、Iwagami N.、Takagi S.、Takagi M.、Ogohara K.、Kashimura H.、Horinouchi T.、Sato N.、Yamada M.、Yamamoto Y.、Ohtsuki S.、Sugiyama K.、Ando H.、Takamura M.、Yamada T.、Satoh T.、Nakamura M.
  • Journal Title: Geophysical Research Letters Volume: 44 Issue: 24
  • DOI: 10.1002/2017gl075792
  • Peer Reviewed / Open Access
• [Journal Article] Large stationary gravity wave in the atmosphere of Venus (2017)
  • Author(s): Fukuhara, T., M. Futaguchi, G. L. Hashimoto, T. Horinouchi, T. Imamura, N. Iwagaimi, T. Kouyama, S. Murakami, M. Nakamura, K. Ogohara, M. Sato, T. M. Sato, M. Suzuki, M. Taguchi, S. Takagi, M. Ueno, S. Watanabe, M. Yamada, A. Yamazaki
  • Journal Title: Nature Geosci. Volume: 10 Issue: 2 Pages: 85-88
  • DOI: 10.1038/ngeo2873
  • Peer Reviewed / Open Access
• [Journal Article] AKATSUKI returns to Venus (2016)
  • Author(s): Nakamura, M., Imamura, T., Ishii, N., Abe, T., Kawakatsu, Y., et al. (Sato, T.M. 52名中38番目)
  • Journal Title: Earth, Planets and Space Volume: - Issue: 1 Pages: 68-75
  • DOI: 10.1186/s40623-016-0457-6
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Stationary features at the Venus cloud top seen in Akatsuki/IR2 2.02-μm dayside images (2017)
  • Author(s): Takao M. Sato, Shin-ya Murakami, Takeshi Horinouchi, Takehiko Satoh, Javier Peralta, Takeshi Imamura
  • Organizer: JpGU-AGU Joint Meeting 2017
  • Int'l Joint Research
• [Presentation] Coordinated observation of Venus cloud top with Subaru and Akatsuki (2017)
  • Author(s): Takao M. Sato, Hideo Sagawa, Toru Kouyama, Makoto Taguchi, Yeon Joo Lee, Javier Peralta, Masahiro Takagi, George Hashimoto, Takehiko Satoh, Yasumasa Kasaba, Shohei Aoki, Tetsuya Fukuhara, Atsushi Yamazaki, Takeshi Imamura, Masato Nakamura
  • Organizer: JpGU-AGU Joint Meeting 2017
  • Int'l Joint Research
• [Presentation] Venus cloud top structure seen by the coordinated Subaru and Akatsuki observations (2017)
  • Author(s): Takao M. Sato, Hideo Sagawa, Toru Kouyama, Makoto Taguchi, Yeon Joo Lee, Javier Peralta, Masahiro Takagi, George L. Hashimoto, Takehiko Satoh, Yasumasa Kasaba, Shohei Aoki, Tetsuya Fukuhara, Atsushi Yamazaki, Takeshi Imamura, Masato Nakamura
  • Organizer: European Planetary Science Congress 2017
  • Int'l Joint Research
• [Presentation] Radiative transfer modeling for analyses with Akatsuki/IR2 images (2017)
  • Author(s): Takao M. Sato, Takehiko Satoh, George L. Hashimoto, Yeon Joo Lee, Hideo Sagawa, Yasumasa Kasaba
  • Organizer: 49th Annual Division for Planerary Sceiences Meeting
  • Int'l Joint Research
• [Presentation] あかつきIR2による金星夜面強化観測 (2016)
  • Author(s): 佐藤隆雄，佐藤毅彦，中村正人，上野宗孝，鈴木睦，はしもとじょーじ，榎本孝之，高見康介，中川広務，笠羽康正
  • Organizer: 第140回地球電磁気・地球惑星圏学会
  • Place of Presentation: 九州大学伊都キャンパス（福岡県福岡市）
  • Year and Date: 2016-11-19
• [Presentation] Subaru/COMICSの中間赤外分光データで調べる金星雲頂構造 (2016)
  • Author(s): 佐藤隆雄，佐藤毅彦，佐川英夫，山崎敦，神山徹，今村剛
  • Organizer: 日本地球惑星科学連合2016
  • Place of Presentation: 幕張メッセ（千葉県千葉市）
  • Year and Date: 2016-05-20
• [Presentation] Mid-infrared spectroscopy of Venus obtained by Subaru/COMICS (2016)
  • Author(s): Sato, T.M., Satoh, T., Sagawa, H., Yamazaki, A., Kouyama, T., Imamura, T.
  • Organizer: International Venus Conference 2016
  • Place of Presentation: Merton College, Oxford, UK
  • Year and Date: 2016-04-05
  • Int'l Joint Research
• [Presentation] 金星探査機「あかつき」と地上望遠鏡によるシナジー (2016)
  • Author(s): 佐藤隆雄
  • Organizer: 地球型惑星圏環境に関する研究集会
  • Place of Presentation: 立教大学池袋キャンパス（東京都豊島区）
  • Invited