日本地球惑星科学連合2019年大会

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セッション記号 P (宇宙惑星科学) » P-PS 惑星科学

[P-PS08] 月の科学と探査

2019年5月30日(木) 09:00 〜 10:30 103 (1F)

コンビーナ:長岡 央(宇宙航空研究開発機構)、鹿山 雅裕(東北大学大学院理学研究科地学専攻)、西野 真木(宇宙航空研究開発機構宇宙科学研究所)、諸田 智克(名古屋大学大学院環境学研究科)、座長:田中 智西野 真木(名古屋大学宇宙地球環境研究所)

09:15 〜 09:30

[PPS08-02] New Results from Restored Apollo Magnetic Field Records

*Peter J Chi1 (1.University of California Los Angeles)

キーワード:Moon, Apollo magnetic field experiments, plasma waves at the Moon, magnetic sounding of lunar interior, solar wind interaction with the Moon

Three Apollo missions collected digital magnetic field measurements by the Lunar Surface Magnetometers on the surface (Apollo 12, 15, and 16) and by Subsatellite Biaxial Magnetometers in orbit surrounding the Moon (Apollo 15 and 16). After approximately a half century, the Apollo 15 and 16 missions are still the only lunar missions conducting simultaneous surface and orbital magnetic field experiments. The Apollo magnetic field experiments enabled many first discoveries, such as the lunar magnetic anomalies and the electrical conductivity of the Moon.

A recent effort has restored all the Apollo magnetic field records from the archaic data format originally archived. The restored LSM data have revealed many narrowband ion cyclotron waves in the Earth’s magnetotail that were not investigated during Apollo years. The restored data also allow re-analyses for the Moon-solar wind interaction and magnetic sounding of the lunar interior. We find that the observed transfer function responses in both tangential and radial components on the lunar surface are consistent with theoretical expectations at least for frequencies greater than 10-4 Hz. The comparison between SBM and LSM data indicates that, when the Moon is in the solar wind, the surface magnetic field is slightly enhanced on the sunward side. This paper summarizes the recent findings from the restored Apollo magnetic field data and discusses the unexplored topics for future magnetic field measurements on the lunar surface.