[P-PS04] 太陽系小天体：はやぶさ２等の宇宙ミッションからの新展開

[PPS04-P22] Current status and science of DESTINY+

*荒井 朋子¹、小林 正規¹、石橋 高¹、木村 宏¹、平井 隆之¹、洪 鵬¹、吉田 二美²、尾崎 直哉³、山本 高行³、豊田 裕之³、西山 和孝³、今村 裕志³、高島 建³、デスティニープラス 理学チーム (1.千葉工業大学　惑星探査研究センター、2.産業医科大学、3.宇宙航空研究開発機構　宇宙科学研究所)

キーワード：デスティニープラス、フェートン、ふたご座流星群、活動的小惑星、宇宙塵、フライバイ

DESTINY+ (Demonstration and Experiment of Space Technology for INterplanetary voYage with Phaethon fLyby and dUst Science) was selected in 2017 as a mission for JAXA/ISAS smallclass program. It will be launched in 2024 and fly by Phaethon in 2028. It is a joint mission of technology demonstration and scientific observation. The engineering mission is led by ISAS/JAXA and the science mission is led by PERC, Chiba Inst. of Technology (ChiTech). It will test high performance electric propelled vehicle technology and high-speed flyby of asteroid (3200) Phaethon and possibly asteroid 2005UD, a likely break-up body from Phaethon, as an extended mission. Engineering challenges include an up-close encounter at a distance of 500 km from Phaethon with radio-optical hybrid navigation guidance and control, and autonomous imaging based on optical information for target tracking during a high-speed flyby of about 35km/sec. The science goal is to understand the nature and origin of cosmic dust brought onto the Earth, in the context of exogenous contribution of carbon and organics for possible prebiotic seeds of the terrestrial life. Phaethon is a parent body of Geminid meteor shower, and thus a known source to periodically provide dust to the Earth, via the dust stream. The science objectives are two folded: (1) in-situ analyses of velocity, arrival direction, mass and chemical composition of interplanetary and interstellar dust particles around 1 au, the dust trail, and nearby Phaethon, and (2) flyby imaging of Phaethon to study its geology, for understanding dust ejection mechanism of active asteroid and the surface compositional variation. Science payloads include a panchromatic, telescopic camera with a tracking capability (TCAP), a visible-NIR multi-band camera with four bands of 425, 550, 500, 850 nm (MCAP), and a dust analyzer (DDA). While the two cameras are developed by PERC, Chitech, DDA is developed by Univ. of Stuttgart, as an international collaboration. Ground calibration for DDA is being performed with German/Japanese joint efforts. International observation campaign for Phaethon was conducted in December 2017, and that of asteroid 2005 UD in October, 2018. Also, international observation campaign for stellar occultation by Phaethon was performed in 2019. Here, we present the current status and science of DESTINY+ mission.