Profile Information
- Affiliation
- Director General, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Degree
- Ph.D(Mar, 1988, The University of Tokyo)Master(Mar, 1985, The University of Tokyo)
- ORCID ID
https://orcid.org/0000-0002-6871-3133- J-GLOBAL ID
- 200901080116851867
- researchmap Member ID
- 1000144511
- External link
Dr. Hitoshi Kuninaka received his Ph.D from the University of Tokyo in 1988. He was promoted to Associate Professor and Professor of the Japan Aerospace Exploration Agency, Japan, in 2000 and 2005, respectively. He held concurrently the post of Professor in the Department of Aeronautics and Astronautics, University of Tokyo, Japan, from 2004 to 2018. In 2018, he became the Director General of the Institute of Space and Astronautical Science (ISAS) as well as Vice President of Japan Aerospace Exploration Agency (JAXA).
He researches the plasma interaction of satellites and develops electric propulsions. He participated in the satellite project, Space Flyer Unit, from 1988 to 1996, and successfully brought it back to Earth via Space Shuttle STS-72. Microwave discharge ion engines, which were invented and developed by Dr. Kuninaka, took Hayabusa explorer on a round-trip journey between Earth and an asteroid from 2003 to 2010. The engines also have been propelling Hayabusa2 explorer toward another asteroid since 2014. The Hayabusa project team has been honored with the National Science Society (NSS) Space Pioneer Award, American Institute of Aeronautics and Astronautics (AIAA) Electric Propulsion Outstanding Technical Achievement Award, NSS Von Braun Award, International Academy of Astronautics Laurels for Team Achievement, SpaceOps Organization International SpaceOps Award for Outstanding Achievement among others. He received AIAA Fellow membership in 2012 and IAA Space Engineering Section Correspond Member in 2019.
Research Interests
3Research Areas
3Major Research History
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Apr, 2018 - Mar, 2025
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Apr, 2005 - Mar, 2018
Education
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Apr, 1983 - Mar, 1988
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Apr, 1979 - Mar, 1983
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Apr, 1976 - Mar, 1979
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Apr, 1973 - Mar, 1976
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Apr, 1967 - Mar, 1973
Major Awards
39-
Nov, 2021
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Dec, 2020
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Sep, 2020
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Nov, 2017
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Apr, 2015
Major Papers
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Vacuum and Surface Science, 63(4) 183-188, Apr 10, 2020 InvitedLead authorThe microwave discharge plasma sources contributed to the reciprocating powered flight between Earth and the asteroids as the main propulsion system of the Hayabusa and Hayabusa2 asteroid explorers, and showed its high performance. The electron cyclotron resonance discharge only heats the electrons and does not induce ion sputtering damage. The reasons of high performance and long life are derived and proved theoretically, experimentally, and in practical use in space. In addition to further space applications, efforts are also being made for industrial applications.
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J. Inst. Electrostat. Jpn., 44(3) 128-134, Mar, 2020 Peer-reviewedLast authorElectric charge accumulation can cause failure during vacuum manufacturing processes. For the charge neutralization in vacuum environment, cyclical change of its pressure to produce intermittent passive discharges according to the Paschen's law is often used; however, it is still insufficient to increse production efficiency. The goal of this study is to increase the charge neutralization rate in vacuum environments (10-10-4 Pa) using an electron cyclotron resonance (ECR) plasma source developed by JAXA (Japan Aerospace Exploration Agency) to neutralize the charge of spacecrafts emitting ions from their thrusters. We investigated the charge neutralization of a 50 mm × 50 mm plate with capacitance of 1.7 μF at initial voltage of 200 V, where the plate is placed 30 cm away from the ECR neutralizer. The time required to reach 37% of the initial voltage was 0.1 s for positive charge and 27 s for negative charge. In addition, improvement of the electron extraction electrode for the ECR neutralizer led to five times higher neutralization current compared to the previous ECR neutralizer at 10 W power and 0.1 mg/s xenon flow rate.
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Acta Astronautica, 166 69-77, Jan, 2020 Peer-reviewedLast author
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日本惑星科学会誌, 22(2), 2013 Invited宇宙工学は、宇宙への往来の実現を目指し、技術を切磋琢磨してきた。その成果の端的な例は、「はやぶさ」にて実現された地球〜小惑星間往復航行(2003年〜2010年)である。それにより、科学や技術分野を越えて、より大きな世界観を得ることができた。次の新しい知見を得るために、科学的な意義はもちろんのこと、「宇宙を自在に往来する独自能力の維持発展」と「人類の活動領域の宇宙への拡大」という宇宙工学・宇宙探査に跨る目標を担い、「はやぶさ2」小惑星探査ミッションが開発中である。
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JOURNAL OF PROPULSION AND POWER, 23(3) 544-551, May, 2007 Peer-reviewed
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プラズマ・核融合学会誌, 82(5) 300-305, May, 2006 InvitedLead authorプラズマ生成に直流放電を利用する従来式電気ロケットは、放電電極損耗という劣化要素を含み、長寿命・高信頼を必須とする宇宙機械において重大な問題を抱えていた。これをマイクロ波放電による無電極化にて根本的に解決し、日本独自のシステムとしてマイクロ波放電式イオンエンジンが開発された。「はやぶさ」小惑星探査機は、2003年5月から2年余を掛けて、太陽距離0.86天文単位から1.7天文単位に至る広範な宇宙を走破して、目的天体「いとかわ」とのランデブーに成功した。この間、主推進装置である4台のマイクロ波放電式イオンエンジンは、22kgの推進剤キセノンを消費して、総増速量1,400m/s、延べ作動時間25,800時間という世界一級の成果を挙げた。慣性(弾道)飛行していたこれまでの「人工惑星」「人工衛星」とは異なり、高性能推進機関を搭載する宇宙機は、動力航行する能力を持ち、「宇宙船」に分類されるべき新しい技術である。
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日本航空宇宙学会誌, 53(618) 203-210, Jul, 2005 Invited
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ACTA ASTRONAUTICA, 55(1) 27-38, Jul, 2004 Peer-reviewedLead author
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日本航空宇宙学会論文集, 52(602) 129-134, 2004 Peer-reviewedThe microwave discharge ion engine generates plasmas of the main ion source as well as the neutralizer using 4GHz microwave without discharge electrodes and hollow cathodes, so that long life and durability against oxygen and air are expected. MUSES-C “HAYABUSA” spacecraft installing four microwave discharge ion engines was launched into deep space by M-V rocket on May 9, 2003. After vacuum exposure and several runs of baking for reduction of residual gas the ion engine system established the continuous acceleration of the spacecraft toward an asteroid. The Doppler shift measurement of the communication microwave revealed the performance of ion engines, which is 8mN thrust force for a single unit with 3,200sec specific impulse at 23mN/kW thrust power ratio. At the beginning of December 2003 the accumulated operational time exceeded 7,000 hours and units.
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JOURNAL OF PROPULSION AND POWER, 14(6) 1022-1026, Nov, 1998 Peer-reviewed
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Aeronautical and space sciences Japan, 46(530) 174-180, Mar, 1998 Invited
Misc.
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令和3年度宇宙輸送シンポジウム: 講演集録 = Proceedings of Space Transportation Symposium FY2021, Jan, 2022令和3年度宇宙輸送シンポジウム(2022年1月13日-14日. オンライン開催) Space Transportation Symposium FY2021 (January 13-14, 2022. Online Meeting) 非化学推進優秀学生賞 資料番号: SA6000173064 STEP-2021-025
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令和二年度宇宙輸送シンポジウム: 講演集録 = Proceedings of Space Transportation Symposium FY2020, Jan, 2021令和二年度宇宙輸送シンポジウム(2021年1月14日-15日. オンライン開催) Space Transportation Symposium FY2020 (January 14-15, 2021. Online Meeting) PDF再処理の為、2023年2月27日に差替 資料番号: SA6000160089 レポート番号: STEP-2020-053
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マイクロ波放電型イオンスラスタの放電室形状と性能の関係—Effect of Discharge Chamber Geometry on the ECR Ion Thruster Performance平成30年度宇宙輸送シンポジウム: 講演集録 = Proceedings of Space Transportation Symposium FY2018, Jan, 2019平成30年度宇宙輸送シンポジウム(2019年1月17日-18日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)), 相模原市, 神奈川県 Space Transportation Symposium FY2018 (January 17-18, 2019. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan 資料番号: SA6000136059 レポート番号: STEP-2018-003
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平成30年度宇宙輸送シンポジウム: 講演集録 = Proceedings of Space Transportation Symposium FY2018, Jan, 2019平成30年度宇宙輸送シンポジウム(2019年1月17日-18日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)), 相模原市, 神奈川県 Space Transportation Symposium FY2018 (January 17-18, 2019. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan 資料番号: SA6000136077 レポート番号: STEP-2018-021
Major Books and Other Publications
5Presentations
190-
41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2005
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International Astronautical Federation - 55th International Astronautical Congress 2004, 2004
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International Astronautical Federation - 55th International Astronautical Congress 2004, 2004
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40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2004
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Meeting Abstracts of the Physical Society of Japan, 2004, The Physical Society of Japan
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PROCEEDINGS OF THE FIFTH IAA INTERNATIONAL CONFERENCE ON LOW-COST PLANETARY MISSIONS, 2003, ESA PUBLICATIONS DIVISION C/O ESTECThe MUSES-C was launched on May 9(th) of this year and was named 'Hayabusa'. It takes an aim at the world's first sample and return from a near Earth asteroid, 1998SF36 now renamed "Itokawa". The spacecraft is a kind of technology demonstrator with four key technologies. The paper presents a quick report on the initial operation of the ion engines aboard and will show how the attitude control has been performed incorporating the closed loop de-saturation function onboard. The paper also presents how much delta-V has been applied to the spacecraft as well as how the orbit determination under the low-thrust acceleration has been performed.
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X-RAY AND GAMMA-RAY TELESCOPES AND INSTRUMENTS FOR ASTRONOMY, PTS 1 AND 2, 2003, SPIE-INT SOC OPTICAL ENGINEERINGStrategy of formation flying for the X-ray Evolving Universe Spectroscopy mission (XUES) is discussed. in which an X-ray telescope of 10 in diameter and 50 in focal length will be constructed in orbit by formation flying the X-ray mirror and the focal plane X-ray detectors on two separate spacecrafts. We first studied the thrust, force required to keep the detector spacecraft (DSC) in the non-Keplerian orbit. We find the, direction of the thrust vector rotates twice per a single spacecraft orbital evolution along a circle parallel to the orbital plane. The absolute value of thrust needs to be varied by a factor of two or less. The maximum thrust force required is 0.47 N assuming a 600 km altitude and a 4000 kg DSC mass. The present baseline design requires no moving mechanism. instead requires a large amount of propellant because of relatively, low thruster efficiency. The spacecraft is estimated to weigh about 6000 kg. We studied an alternative design in which the thruster efficiency is optimized and showed that the spacecraft mass can be reduced to 4000 kg. This. however. requires a rotation mechanism and additional constraints on the spacecraft operation.
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34th AIAA Plasmadynamics and Lasers Conference, 2003
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Large microwave discharge type ion engine μ20 and 10000 seconds high specific thrust engine μ10HIsp.宇宙科学シンポジウム 平成14年度 第3回, 2003
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宇宙科学シンポジウム, Nov 19, 2001, 宇宙航空研究開発機構宇宙科学研究本部
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Fluids engineering conference ..., Sep 28, 2001, The Japan Society of Mechanical Engineers
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37th Joint Propulsion Conference and Exhibit, 2001
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35th Intersociety Energy Conversion Engineering Conference and Exhibit, 2000
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36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2000
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AIAA Paper 96-2979, 1996
Professional Memberships
5Works
9Major Research Projects
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研究成果展開事業(産学官の連携による共創の「場」の形成支援), 科学技術振興機構, Jul, 2015 - Mar, 2020
Industrial Property Rights
17Major Media Coverage
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NHK, NHKスペシャル, https://www.facebook.com/NHKonline/posts/2639642986062350/, Mar 17, 2019 TV or radio program