[P-CG23] [EE] 宇宙・惑星探査の将来計画と関連する機器開発の展望

[PCG23-12] 超小型探査機を用いた地球-月 L2ポイントからのプラズマ圏の極端紫外光観測

*吉岡 和夫¹、桑原 正輝²、村上 豪³、吉川 一朗² (1.東京大学大学院理学系研究科地球惑星科学専攻、2.東京大学大学院新領域創生科学研究科複雑理工学専攻、3.宇宙航空研究開発機構宇宙科学研究所)

キーワード：nano-spacecraft, Plasmasphere, EUV imaging

The nano-spacecraft mission named EQUULEUS is now under development. It will be launched in 2018 as one of the secondary payloads of SLS (Space Launch System) mission of NASA. EQUULEUS will fly to a libration orbit around the Earth-Moon L2 point and demonstrate trajectory control techniques within the Sun-Earth-Moon region (e.g. low-energy transfers using weak stability regions) for the first time by a nano-spacecraft. A small telescope in extreme ultraviolet named PHOENIX will be boarded on EQUULEUS. It consists of multilayer-coated entrance mirror (diameter of 6 cm) and photon counting device (microchannel plate and resistive anode), and electronics parts. The reflectance of mirror is optimized for the emission line of ionic helium (wavelength of 30.4 nm) which is the important component of the plasmasphere of the Earth. By flying far from the Earth, the entire image of plasmasphere can be obtained. Our observation will complement and enhance the geospace in-situ plasma measurements conducted by the ERG (JAXA) and Van Allen probe (NASA) missions. As a result, we can understand natures of geospace and radiation belt, which we have to understand to realize future manned space exploration. In this presentation, the mission concept and the design of the telescope will be shown. The status of the development will also be shown.