Dept. of Interdisciplinary Space Science
基本情報
- 所属
- 国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 学際科学研究系 准教授
- 研究者番号
- 80873380
- J-GLOBAL ID
- 202001017783214748
- researchmap会員ID
- R000000751
研究キーワード
5研究分野
1経歴
3-
2025年1月
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2020年1月 - 2024年12月
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2019年4月 - 2019年12月
学歴
3-
2016年4月 - 2019年3月
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2014年4月 - 2016年3月
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2010年4月 - 2014年3月
受賞
5-
2015年3月
論文
18-
Acta Astronautica 227 114-125 2025年2月 査読有り
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Springer Aerospace Technology 695-720 2024年12月14日
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Space Science Reviews 220(1) 2024年1月24日Abstract Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum $\varDelta $V capability of $600\text{ ms}^{-1}$. Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.
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Journal of Evolving Space Activities 2 n/a 2024年 査読有り筆頭著者責任著者In recent years, nanosatellites and microsatellites have become more than just a technology demonstration tool, but also a tool that can bring about scientific and economic outcomes, mainly in low Earth orbit. On the other hand, the use of microsatellites in interplanetary missions is still limited. There are two main problems in using microsatellites for interplanetary missions. To address the issue of lack of launch opportunities directly to the deep space, we are investigating a microsatellite system that is capable of escaping from Earth orbit, which has relatively frequent launch opportunities such as GTO, into deep space using its own propulsion system. We conducted the conceptual design of a microsatellite for the GEO-X mission, which will perform X-ray imaging of the Earth's magnetosphere from the orbit as far as Lunar Orbit. We designed a 50 kg microsatellite using a 500 N class hybrid kick motor for orbit transfer from GTO, based on previous rideshare launch opportunities. Since suppression of the disturbance torque is important when using such a high thrust propulsion system, a spin-stabilized system is used. A conceptual design was performed taking these considerations into account, and rough feasibility and future issues were extracted.
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Journal of Evolving Space Activities 2 n/a 2024年 査読有り筆頭著者責任著者Comet Interceptor is ESA's F-class mission to explore a long-period comet. Comet Interceptor performs a flyby observation with 3 spacecraft: 1 main spacecraft (spacecraft A) and 2 small probes (probe B1 and probe B2). JAXA will provide one of the small probes, probe B1, taking advantage of its past achievements in micro spacecraft. The probe B1 is a micro spacecraft weighing about 35 kg. The bus size is about 24U, and the envelope including protrusions is about 50 cm cubic. This probe will carry three types of science instruments for complementary observations with ESA's instruments onboard the main spacecraft and another small probe at multiple points. The first instrument is a wide-angle camera and a narrow-angle camera (WAC/NAC) for optical observations of the nucleus. The second is Hydrogen Lyman-alpha Imager (HI) to observe a Lyman-alpha of coma, and the third is a Plasma Suite (PS) to observe plasma using an ion sensor and a magnetometer. The probe B1 performs a flyby observation without any commands from the ground, considering dust impacts during the closest approach to the comet. This paper presents the result of conceptual design for the small probe under severe constraints and its future challenges.
MISC
30-
Journal of Evolving Space Activities 1 n/a 2023年 査読有りThe low reliability of nano-satellites has become a problem, with the cause often being defects in the design and manufacturing process. It is required to take sufficient measures to account for those defects through ground tests to reduce on-orbit failures. The model-based fault diagnosis method can prevent oversight of fault candidates and compensate for a lack of knowledge in human-based diagnosis. Since the developing time of nano-satellites is limited, fault diagnosis needs to be carried out efficiently also while being careful not to cause secondary faults. This paper presents a novel method that can find the appropriate command to verify candidates of fault location in a satellite. The proposed method can consider the side effect of a command and the efficiency of narrowing them down by using the information transmission path model. In the case study, the proposed method is applied to an earth-orbiting 6U CubeSat, and this case study reveals that 33% of the failures that occur in ground tests can apply to the proposed method. In addition, the proposed method can identify the fault location of some of these failures, although there are several limitations to implementing the proposed method in the actual satellite development.
講演・口頭発表等
82Works(作品等)
2共同研究・競争的資金等の研究課題
2-
日本学術振興会 科学研究費助成事業 学術変革領域研究(B) 2020年10月 - 2023年3月
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2016年9月 - 2019年3月
