Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)
Department of Earth and Planetary Sciences, Tokyo Institute of Technology
Department of Earth and Environmental Sciences, Kumamoto University
Department of Earth and Planetary Sciences, Tokyo Institute of Technology
出版者
宇宙航空研究開発機構宇宙科学研究本部
出版者(英)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)
雑誌名
月・惑星シンポジウム
雑誌名(英)
Proceedings of the ISAS lunar and planetary symposium
巻
42
ページ
92 - 95
発行年
2009-08
会議概要(会議名, 開催地, 会期, 主催者等)
第42回 月・惑星シンポジウム(2009年8月5-7日, 宇宙航空研究開発機構宇宙科学研究本部)
会議概要(会議名, 開催地, 会期, 主催者等)(英)
The 42nd ISAS Lunar and Planetary Symposium (August 5-7, 2009. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Sagamihara, Kanagawa Japan
抄録(英)
We study solar wind (SW) intrusion into the near-Moon wake using plasma data obtained by the SELENE (KAGUYA) spacecraft. It has been known that SW protons flowing around the Moon access the central region of the distant lunar wake, while SW intrusion deep into the near-Moon wake has never been expected. Here we review two mechanisms (which we call type-I and type-II, respectively) of SW proton entry deep into the near-Moon wake, using plasma and magnetic field data obtained by the SELENE spacecraft at 100 km height from the lunar surface. The key process of the type-I entry is acceleration of the SW protons by the ambipolar electric field around the wake boundary. This entry mechanism lets the SW protons come fairly deep into the wake (solar zenith angle (SZA) 150 degrees) at 100 km height. On the other hand, the type-II entry is based on the SW proton scattering on the dayside; SW protons are once scattered at the lunar dayside surface, picked-up by the SW motional electric field, and finally access the deepest wake (150<SZA<180 degrees). Both entry mechanisms occur in the direction perpendicular to the interplanetary magnetic field, but only type-II mechanism lets the SW protons come into the deepest wake that the SW protons are not anticipated to access. The type-II entry forms the proton-governed region (PGR) in one hemisphere of the near-Moon wake, giving rise to a strong asymmetry of the near-Moon wake environment. Our results mean that not only SW electrons but also protons are crucial for plasma environment in the wake.
内容記述
形態: カラー図版あり
形態: CD-ROM1枚
著者人数: 13人
内容記述(英)
Physical characteristics: Original contains color illustrations
Number of authors: 13
Note: One CD-ROM