@inproceedings{oai:jaxa.repo.nii.ac.jp:00007440,
 author = {池田, 人 and 小湊, 隆 and 松岡, 正敏 and 大西, 隆史 and 吉川, 真 and Ikeda, Hitoshi and Kominato, Takashi and Matsuoka, Masatoshi and Onishi, Takafumi and Yoshikawa, Makoto},
 book = {第17回アストロダイナミクスシンポジウム講演後刷り集　2007, Proceedings of 17th Workshop on JAXA Astrodynamics and Flight Mechanics},
 month = {Mar},
 note = {探査機「はやぶさ(MUSES-C: Asteroid Sample-return Spacecraft)」は、2003年5月9日に内之浦宇宙空間観測所からM-Vロケットによって打上げられ、電気推進と地球スウィングバイによる軌道変更を経て、2005年9月12日に小惑星イトカワに到着した。搭載カメラ、近赤外分光器、蛍光X線分光器、レーザ高度計などの科学機器を使用した各種科学観測により、イトカワに関するさまざまな物理パラメータが解析され、小惑星の起源、形成過程を解明するための新しい知見をもたらした。イトカワ滞在時、リアクションホイールに不具合が生じたため、化学スラスタを使用して姿勢制御を行なっていたが、スラスタ推力の微小なアンバランスが積算され、軌道運動に影響を与える結果となった。本解析では、この姿勢制御による影響を評価するために簡単なスラスタ推力差モデルを導入。また、イトカワの形状を考慮した重力場モデルとして、球面調和関数を用いた重力場モデルやイトカワの形状モデルを使用したポリヘドロン重力場モデルを組込み、光学航法データ、ドップラーデータを用いて小惑星接近時の探査機の軌道、およびイトカワの重力場について解析を行った。, In September 2005, Hayabusa (MUSES-C: Asteroid Sample-return Spacecraft) spacecraft successfully had a rendezvous with asteroid 25143 Itokawa. After the arrival, Hayabusa made detailed observations of the asteroid during its rendezvous period (about three months). As the results of various kinds of scientific analysis, a variety of physical parameters of Itokawa (e.g. size, volume, mass, and density) were derived. As to the orbit determination of Hayabusa spacecraft, during the cruise phase, the radiometric (two-way X-band range and Doppler) data were used for analysis. On the other hand, during the approach phase or rendezvous phase, we could obtain the optical data by means of star tracker or optical navigation camera, thus both the radiometric and the optical data were used for orbit determination. The present paper will report on the results of the orbit determination of Hayabusa during the close proximity phase. I will also mention about the mass estimation of Itokawa in this period. The data used in this analysis are two-way X-band Doppler data and the position data, which were calculated from optical navigation camera's data. As well as the large orbital maneuvers and the gravitational acceleration of Itokawa, the effect of solar radiation pressure, and the effect of attitude control are also taken into account for the calculation. As to the gravity model of Itokawa, a spherical-harmonics gravity model or a polyhedron gravity model are used depending on the situation., 資料番号: AA0063718003},
 pages = {12--17},
 publisher = {宇宙航空研究開発機構宇宙科学研究本部, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)},
 title = {Orbit determination of Hayabusa and gravity estimation of Itokawa during close proximity phase},
 year = {2008}
}