Earth, Planets and Space (Oct 2017)
Initial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki
- Takeshi Imamura,
- Hiroki Ando,
- Silvia Tellmann,
- Martin Pätzold,
- Bernd Häusler,
- Atsushi Yamazaki,
- Takao M. Sato,
- Katsuyuki Noguchi,
- Yoshifumi Futaana,
- Janusz Oschlisniok,
- Sanjay Limaye,
- R. K. Choudhary,
- Yasuhiro Murata,
- Hiroshi Takeuchi,
- Chikako Hirose,
- Tsutomu Ichikawa,
- Tomoaki Toda,
- Atsushi Tomiki,
- Takumi Abe,
- Zen-ichi Yamamoto,
- Hirotomo Noda,
- Takahiro Iwata,
- Shin-ya Murakami,
- Takehiko Satoh,
- Tetsuya Fukuhara,
- Kazunori Ogohara,
- Ko-ichiro Sugiyama,
- Hiroki Kashimura,
- Shoko Ohtsuki,
- Seiko Takagi,
- Yukio Yamamoto,
- Naru Hirata,
- George L. Hashimoto,
- Manabu Yamada,
- Makoto Suzuki,
- Nobuaki Ishii,
- Tomoko Hayashiyama,
- Yeon Joo Lee,
- Masato Nakamura
Affiliations
- Takeshi Imamura
- Graduate School of Frontier Sciences, The University of Tokyo
- Hiroki Ando
- Faculty of Science, Kyoto Sangyo University
- Silvia Tellmann
- Abteilung Planetenforschung, Rheinisches Institut für Umweltforschung, Universität zu Köln
- Martin Pätzold
- Abteilung Planetenforschung, Rheinisches Institut für Umweltforschung, Universität zu Köln
- Bernd Häusler
- Institut für Raumfahrttechnik und Weltraumnutzung, Universität der Bundeswehr München
- Atsushi Yamazaki
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Takao M. Sato
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Katsuyuki Noguchi
- Faculty of Science, Nara Women’s University
- Yoshifumi Futaana
- Swedish Institute of Space Physics
- Janusz Oschlisniok
- Abteilung Planetenforschung, Rheinisches Institut für Umweltforschung, Universität zu Köln
- Sanjay Limaye
- Space Science and Engineering Center, University of Wisconsin
- R. K. Choudhary
- Space Physics Laboratory, Vikram Sarabhai Space Center
- Yasuhiro Murata
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Hiroshi Takeuchi
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Chikako Hirose
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Tsutomu Ichikawa
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Tomoaki Toda
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Atsushi Tomiki
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Takumi Abe
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Zen-ichi Yamamoto
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Hirotomo Noda
- National Astronomical Observatory of Japan
- Takahiro Iwata
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Shin-ya Murakami
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Takehiko Satoh
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Tetsuya Fukuhara
- College of Science, Rikkyo University
- Kazunori Ogohara
- The University of Shiga Prefecture
- Ko-ichiro Sugiyama
- National Institute of Technology, Matsue College
- Hiroki Kashimura
- Center for Planetary Science/Department of Planetology, Kobe University
- Shoko Ohtsuki
- Senshu University
- Seiko Takagi
- Tokai University, Research and Information Center
- Yukio Yamamoto
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Naru Hirata
- The University of Aizu
- George L. Hashimoto
- Department of Earth Sciences, Okayama University
- Manabu Yamada
- Planetary Exploration Research Center, Chiba Institute of Technology
- Makoto Suzuki
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Nobuaki Ishii
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Tomoko Hayashiyama
- Japan Aerospace Exploration Agency
- Yeon Joo Lee
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Masato Nakamura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- DOI
- https://doi.org/10.1186/s40623-017-0722-3
- Journal volume & issue
-
Vol. 69,
no. 1
pp. 1 – 11
Abstract
Abstract After the arrival of Akatsuki spacecraft of Japan Aerospace Exploration Agency at Venus in December 2015, the radio occultation experiment, termed RS (Radio Science), obtained 19 vertical profiles of the Venusian atmosphere by April 2017. An onboard ultra-stable oscillator is used to generate stable X-band downlink signals needed for the experiment. The quantities to be retrieved are the atmospheric pressure, the temperature, the sulfuric acid vapor mixing ratio, and the electron density. Temperature profiles were successfully obtained down to ~ 38 km altitude and show distinct atmospheric structures depending on the altitude. The overall structure is close to the previous observations, suggesting a remarkable stability of the thermal structure. Local time-dependent features are seen within and above the clouds, which is located around 48–70 km altitude. The H2SO4 vapor density roughly follows the saturation curve at cloud heights, suggesting equilibrium with cloud particles. The ionospheric electron density profiles are also successfully retrieved, showing distinct local time dependence. Akatsuki RS mainly probes the low and middle latitude regions thanks to the near-equatorial orbit in contrast to the previous radio occultation experiments using polar orbiters. Studies based on combined analyses of RS and optical imaging data are ongoing. Graphical abstract .
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