著者
吉川 真 吉光 徹雄 高木 靖彦 出村 裕英 野口 高明 宮本 英昭 川口 淳一郎 藤原 顕 安部 正真 岩田 隆浩 川勝 康弘 田中 智 森 治 矢野 創
出版者
日本惑星科学会
雑誌
日本惑星科学会秋季講演会予稿集
巻号頁・発行日
vol.2006, pp.7, 2006

小惑星探査機「はやぶさ」による小惑星イトカワの観測で、500m程度の小さなS型小惑星についての理解が深まったが、我々は、さらに次の小天体探査ミッションについての検討を行っている。次のミッションとしては、S型と同様に小惑星帯で主要なタイプとなっているC型小惑星の探査を行いたい。このタイプでは、有機物や水をより多く含んでいると思われており、生命前駆物質の科学としても重要である。ここでは、これまでのミッション検討結果をまとめて報告する。また、是非、多くの研究者に小天体探査に参加してもらうことを呼びかけたい。
著者
岩田 隆浩 南野 浩之 佐々木 健 小川 美奈 並木 則行 花田 英夫 野田 寛大 松本 晃治 今村 剛 石原 吉明 鶴田 誠逸 浅利 一善 劉 慶会 菊池 冬彦 Goossens Sander 石川 利昭 河野 宣之 高野 忠
出版者
日本測地学会
雑誌
測地学会誌 (ISSN:00380830)
巻号頁・発行日
vol.55, no.2, pp.135-150, 2009 (Released:2012-03-28)
参考文献数
16

SELENE Main Orbiter (KAGUYA) has separated two small sub-satellites; (1) the Relay Satellite “OKINA (Rstar)”, and (2) the VLBI Radio Satellite “OUNA (Vstar)”. These sub-satellites started to perform 4-way Doppler measurements using Relay Satellite Transponder (RSAT) and multi-frequency phase-delay differential VLBI using VLBI Radio Sources (VRAD) for lunar gravity mapping. We have developed the frequency conversion system, multi frequency S/X-band vertical dipole antenna, and light weighted S-band patch antenna to perform these missions. Simple structured release mechanism has also been developed and confirmed its performance by ground test and orbital demonstration using micro-Lab Sat. Initial check out were executed and properties of satellite bus equipments, onboard mission instruments, and observation systems including ground stations were evaluated. Electric power and thermal control subsystems have shown that they conduct as designed and inspected in the ground tests. The release mechanisms have given the spin which can maintain the stability of the satellite attitudes. Communication functions of mission instruments conform to the link budgets. These results suggest that OKINA and OUNA have enough performances to produce efficient data by RSAT/VRAD gravity observations.
著者
岩田 隆浩 南野 浩之 佐々木 健 小川 美奈 並木 則行 花田 英夫 野田 寛大 松本 晃治 今村 剛 石原 吉明 鶴田 誠逸 浅利 一善 劉 慶会 菊池 冬彦 Goossens Sander 石川 利昭 河野 宣之 高野 忠
出版者
The Geodetic Society of Japan
雑誌
測地学会誌 (ISSN:00380830)
巻号頁・発行日
vol.55, no.2, pp.135-150, 2009-07-25
被引用文献数
10

SELENE Main Orbiter (KAGUYA) has separated two small sub-satellites; (1) the Relay Satellite "OKINA (Rstar)", and (2) the VLBI Radio Satellite "OUNA (Vstar)". These sub-satellites started to perform 4-way Doppler measurements using Relay Satellite Transponder (RSAT) and multi-frequency phase-delay differential VLBI using VLBI Radio Sources (VRAD) for lunar gravity mapping. We have developed the frequency conversion system, multi frequency S/X-band vertical dipole antenna, and light weighted S-band patch antenna to perform these missions. Simple structured release mechanism has also been developed and confirmed its performance by ground test and orbital demonstration using micro-Lab Sat.<BR> Initial check out were executed and properties of satellite bus equipments, onboard mission instruments, and observation systems including ground stations were evaluated. Electric power and thermal control subsystems have shown that they conduct as designed and inspected in the ground tests. The release mechanisms have given the spin which can maintain the stability of the satellite attitudes. Communication functions of mission instruments conform to the link budgets. These results suggest that OKINA and OUNA have enough performances to produce efficient data by RSAT/VRAD gravity observations.
著者
花田 英夫 岩田 隆浩 菊池 冬彦 劉 慶会 松本 晃治 浅利 一善 石川 利昭 石原 吉明 野田 寛大 鶴田 誠逸 Petrova Natalia Goossens Sander 原田 雄司 佐々木 晶 並木 則行 河野 裕介 岩館 健三郎 亀谷 收 寺家 孝明 柴田 克典 田村 良明 矢作 行弘 増井 亘 田中 孝治 前島 弘則 洪 暁瑜 平 勁松 艾力 玉〓甫 Ellingsen Simon Schlüter Wolfgang
出版者
The Geodetic Society of Japan
雑誌
測地学会誌 (ISSN:00380830)
巻号頁・発行日
vol.55, no.2, pp.203-221, 2009-07-25
被引用文献数
5

The Japanese lunar explorer SELENE (KAGUYA), which has been launched on Sep. 14th, 2007, utilizes VLBI observations in lunar gravimetry investigations. This can particularly improve the accuracy of the low degree gravitational harmonics. Combination of ground based VLBI observations and Doppler measurements of the spacecrafts enable three dimensional orbit determinations and it can improve the knowledge of the gravity field near the limb. Differential VLBI Radio sources called VRAD experiment involves two on-board sub-satellites, Rstar (Okina) and Vstar (Ouna). These will be observed using differential VLBI to measure the trajectories of the satellites with the Japanese network named VERA (VLBI Exploration of Radio Astrometry) and an international VLBI network.<BR>Two new techniques, a multi-frequency VLBI method and the same-beam VLBI method, are used to precisely measure the angular distance between the two sub-satellite radio sources Okina and Ouna. The observations are at three frequencies in S-band, 2212, 2218 and 2287 MHz, and one in X-band, 8456 MHz. We have succeeded in making VLBI observations of Okina/Ouna with VERA and the international network, and have also succeeded in correlating of signals from Okina/Ouna, and obtained phase delays with an accuracy of several pico-seconds in S-band.