[P-PS23_2PO1] 月の科学と探査

[PPS23-P05] SELENE-2/月電磁探査装置 (LEMS): インバージョンのテスト

*松島 政貴¹、清水 久芳²、藤 浩明³、吉村 令慧⁴、高橋 太¹、綱川 秀夫¹、渋谷 秀敏⁵、松岡 彩子⁶、小田 啓邦⁷、小川 和律⁶、田中 智⁶ (1.東京工業大学、2.東京大学地震研究所、3.京都大学、4.京都大学防災研究所、5.熊本大学、6.宇宙航空研究開発機構宇宙科学研究所、7.産業技術総合研究所)

Understanding of lunar origin and evolution can be advanced through investigation of the lunar interior structure. The present thermal state of the Moon can be clues to the Moon's thermal history. In the SELENE-2 mission, we propose a lunar electromagnetic sounder (LEMS) to estimate the electrical conductivity structure of the Moon, which can be used to deduce the thermal structure of the Moon.

Temporal variations in the magnetic field of lunar external origin induce eddy currents in the lunar interior depending on the electrical conductivity structure and frequencies of the temporal variations. The eddy currents, in turn, generate temporal variations in the magnetic field of lunar internal origin. Therefore electromagnetic response of the Moon is obtained from magnetic field measurements by magnetometers onboard a lunar orbiter and a lunar lander. The response function is then used to estimate the electrical conductivity structure by solving an inverse problem. Here we assume a one-dimensional structure for electrical conductivity distribution. We show some results for a test of inversion.