研究者業績
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 太陽系科学研究系 准教授総合研究大学院大学(総研大) 物理科学研究科 宇宙科学専攻 准教授
- J-GLOBAL ID
- 200901006137313045
- researchmap会員ID
- 1000253786
- 外部リンク
研究分野
1経歴
4-
2003年10月 - 現在
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1998年7月 - 2003年9月
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1993年 - 1998年
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1991年 - 1993年
学歴
3-
1988年4月 - 1991年3月
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1986年4月 - 1988年3月
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1982年4月 - 1986年3月
委員歴
1-
2007年 - 2011年
受賞
1論文
125-
EARTH PLANETS AND SPACE 77(1) 2025年2月25日The measurement of virtual height of the sporadic E layer (h'Es) is very sensitive to the type of ionosonde used and the calibration processes. The ionosondes used by the national institute of communication and technology (NICT) has changed several times in the past, resulting in large differences in h'Es before and after the change. We propose a simple method to calibrate h'Es. We used the data of ionosonde observations at four stations, i.e., Wakkanai (45.16 degrees N, 141.75 degrees E), Tokyo (35.71 degrees N, 139.49 degrees E), Yamagawa (31.20 degrees N, 130.62 degrees E), Okinawa (26.68 degrees N, 128.15 degrees E) to calibrate the latest ionosondes VIPIR2, which were installed in May 2017. We carried out the analysis by applying the double-reflection method to the original ionogram images between 2017 and 2021. By developing an automated image detecting algorithm, we were able to process a large amount of data and achieve a calibration with high accuracy. As a result, it was found that the current VIPIR2 data had an offset of 26-28 km.
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AIAA SCITECH 2024 FORUM 2024年One of the first instruments used to monitor laboratory plasmas was the Langmuir probe (LP). This instrument is still one of the key sensors in laboratory plasma investigations. With the access to space, the first sounding rockets with Langmuir Probes were flown in 1946-1947; followed with Langmuir probes on satellites from the early 1960s and on Pioneer Venus Orbiter and subsequent interplanetary probes starting in the 1970s. This paper summarizes some of the experiences of using Langmuir probes over the last 75-years in space, what issues have been encountered, and how to overcome different known effects unique to space flight measurements. This work was done through a number of workshops attended by a number of instrument team members and supported by the ISSI organisation.
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Experimental Astronomy 54(2-3) 521-559 2022年12月 査読有りIn the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribution of externally provided energy to the composing species? (B) How and by how much do plasma-neutral gas interactions contribute toward the growth of heavy complex molecules and biomolecules? Answering these questions is an absolute prerequisite for addressing the long-standing questions of atmospheric escape, the origin of biomolecules, and their role in the evolution of planets, moons, or comets, under the influence of energy sources in the form of electromagnetic and corpuscular radiation, because low-energy ion-neutral cross-sections in space cannot be reproduced quantitatively in laboratories for conditions of satisfying, particularly, (1) low-temperatures, (2) tenuous or strong gradients or layered media, and (3) in low-gravity plasma. Measurements with a minimum core instrument package (< 15 kg) can be used to perform such investigations in many different conditions and should be included in all deep-space missions. These investigations, if specific ranges of background parameters are considered, can also be pursued for Earth, Mars, and Venus.
MISC
55-
電位が変動する飛翔体で使用可能なラングミューアプローブの開発—Development of a Langmuir Probe for Spacecraft with Varying Potential東海大学紀要. 工学部 57(2) 49-53 2018年3月31日
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Proceedings of the International Astronautical Congress, IAC 2016年1月1日Copyright © 2016 by the International Astronautical Federation (IAF). All rights reserved. Japan's Venus Climate Orbiter Akatsuki was proposed to ISAS (Institute of Space and Astronautical Science) in 2001 as an interplanetary mission. We made 5 cameras with narrow-band filters to image Venus at different wavelengths to track the cloud and minor components distribution at different heights to study the Venusian atmospheric dynamics in 3 dimension. It was launched on May 21st, 2010 and reached Venus on December 7th, 2010. With the thrust by the orbital maneuver engine, Akatsuki tried to go into the westward equatorial orbit around Venus with the 30 hours' orbital period, however it failed by the malfunction of the propulsion system. Later the spacecraft has been orbiting the sun for 5 years. On December 7th, 2015 Akatsuki met Venus again after the orbit control and Akatsuki was put into the westward equatorial orbit whose apoapsis is about 0.44 million km and orbital period of 14 days. Its main target is to shed light on the mechanism of the fast atmospheric circulation of Venus. The systematic imaging sequence by Akatsuki is advantageous for detecting meteorological phenomena with various temporal and spatial scales. We have five photometric sensors as mission instruments for imaging, which are 1 m-infrared camera (IR1), 2 m-infrared camera (IR2), ultra-violet imager (UVI), long-wave infrared camera (LIR), and lightning and airglow camera (LAC). These photometers except LIR have changeable filters in the optics to image in certain wavelengths. Akatsuki's long elliptical orbit around Venus is suitable for obtaining cloud-tracked wind vectors over a wide area continuously from high altitudes. With the observation, the characterizations of the meridional circulation, mid-latitude jets, and various wave activities are anticipated. The technical issues of Venus orbit insertion in 2015 and the scientific new results will be given in this paper.
書籍等出版物
2講演・口頭発表等
307-
極域科学・宙空圏・気水圏・生物・地学シンポジウム講演予稿集(CD-ROM) 2010年
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地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM) 2010年
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PROCEEDINGS OF THE 19TH ESA SYMPOSIUM ON EUROPEAN ROCKET AND BALLOON PROGRAMMES AND RELATED RESEARCH 2009年 EUROPEAN SPACE AGENCYSounding rocket experiments have been successively conducted for more than 40 years in Japan. These include various scientific and engineering topics. In this paper, we present recent activities of Japanese sounding rocket experiments for the last two years (2007-2008 fiscal year) and also describe a future direction on the experiment in the mid-term range.
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ベア導電テープテザーの理工学に関する観測ロケット実験—Science and engineering experiment of bare tape-tether on sounding rocket宇宙利用シンポジウム 第24回 平成19年度 = Space Utilization Research: Proceedings of the Twenty-fourth Space Utilization Symposium 2008年3月 宇宙航空研究開発機構宇宙科学研究本部Two projects are introduced in this paper to verify the performance of space tether technology. A sounding rocket will be launched in the summer of 2009 to deploy a bare electro-dynamic tape tether having a length of 300 m. The other project to verify the space tether technology is a small satellite to deploy a bare 25 km electro-dynamic tape tether, and the launch is expected in 2013 with employing a new solid motor rocket. These verifications of tether technology will lead to a large numbers of applications of space tether technology and some future projects are also introduced. 資料番号: AA0063706026
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地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM) 2008年
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European Space Agency, (Special Publication) ESA SP 2007年6月 ESA PUBLICATIONS DIVISION C/O ESTECIn the fiscal year of 2005 and 2006, Japan Aerospace Exploration Agency (JAXA) had successfully launched 10 space vehicles, which included five application satellites, three scientific observation satellites and two sounding rockets with a single stage solid motor. The Institute of Space and Astronautical Science (ISAS) has been continuously conducting space science programs using sounding rockets, scientific satellites and stratospheric balloons. This paper briefly introduces and summarizes the ISAS space activities in the two years.
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European Space Agency, (Special Publication) ESA SP 2007年6月 ESA PUBLICATIONS DIVISION C/O ESTECA fully reusable rocket vehicle is proposed as a sounding rocket for observations of atmospheric phenomena, micro-gravity experiments and so on. Vehicle systems and ground / flight operations are designed for such science observations. For the development of the reusable rocket, a small test vehicle was built and flight-tested. This Reusable Vehicle Testing (RVT) lessons campaign provide repeated experiences of turnaround operations and vertical take-off and landing flights. In the present design of the reusable sounding rocket, the total length and maximum diameter of the vehicle is about 10m and 3m, respectively. The vehicle is propelled by the propulsion system composed of four liquid hydrogen / liquid oxygen engines. The weight of a payload carried to 120 km altitude is 100kg in the nose-fairing. The instrument for observations can be reused because of the repeated flight. The turnaround time for one flight is less than 24 hours (1 day). In the typical ballistic flight up to 120 km, the flight environments under 10(-5)G acceleration is able to be made for about 120 sec. The flight Mach number can be subsonic around the summit in the trajectory. These properties of reusable sounding rocket are expected to be useful and effective for many science missions.
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European Space Agency, (Special Publication) ESA SP 2007年6月 ESA PUBLICATIONS DIVISION C/O ESTECProcesses of energy cascade from suprathermal to thermal electrons significantly affect the thermal structure of the lower ionosphere. The Suprathermal Plasma Analyzer (SPA) was developed to measure an energy distribution of thermal and suprathermal electrons (< 5 eV). The principle of this analyzer is based on the innovative combination of a second harmonic method and a channel electron multiplier. Outstanding point of this analyzer are: 1) accurate calibration of electron energy within the order of 0.01 eV, and 2) the energy resolution smaller than 0.15 eV. The SPA was installed in the sounding rocket S-310-37 and observed the electron energy distribution function at the height from 100 km to 140 km.
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European Space Agency, (Special Publication) ESA SP 2007年6月 ESA PUBLICATIONS DIVISION C/O ESTECThe sounding rocket measurements in the mid-latitude ionosphere suggest that the electron temperature occasionally increases at 100-110 km altitudes during daytime in winter. Detailed study indicates that such a temperature increase is closely related to the existence of the Sq current focus, because the temperature increase becomes significant when the measurement is made near the center of the Sq focus. In order to elucidate a mechanism to cause the electron temperature increase, the sounding rocket experiment was conducted in Uchinoura Space Center in Japan on January 16, 2007. The rocket was launched at 11:20 JST after identifying that the Sq current was approaching to the planned rocket trajectory. The rocket certainly observed the local increase of the electron temperature at the altitude of 97-101 kin. We present a preliminary analysis of the data such as the electron temperature, density, and its perturbation obtained during this campaign.
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日本気象学会大会講演予稿集 2005年4月30日 日本気象学会
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European Space Agency, (Special Publication) ESA SP 2005年In October 2003, a new space agency, JAXA (Japan Aerospace Exploration Agency) was reorganized and started as a primary space agency to promote all space activities in Japan. The Institute of Space and Astronautical Science (ISAS) belonged to JAXA and continued to promote space science and technologies using unique scientific satellites, sounding rockets and balloons. This paper summarizes sounding rocket and ballooning activities of ISAS in the fiscal year of 2003 and 2004, associated with satellite launch programs. In this time period, three sounding rockets and nineteen balloons were launched by ISAS. One of the sounding rocket, S-310-35 was an international collaboration between Japan and Norway, which was launched from Andoya Rocket Range (ARR), Andenes, Norway, so as to study the upper atmospheric dynamics and energetics associated with the auroral energy in the polar lower thermosphere. Through the combination with the national researchers and the cooperation with international organizations, ISAS will keep its own flight opportunities and be able to obtain many new scientific findings.
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日本惑星科学会秋期講演会予稿集 2001年10月6日 日本惑星科学会We present proposals for observing the plasma transportation and circulation processes and the dynamics of the thermal plasmas that are the important element on Venus ionosphere by instruments installed on Venus Climate Orbiter. Main purpose of the observation is to elucidate the following unresolved problems: 1) How the upper atmosphere interacts with the lower atmosphere. 2) How much the energy of the solar wind can enter to the Venus upper atmosphere. 3) How momentum and energy of particles are transported into the upper atmosphere from external regions through the coupling process. In the presentation, the observation target and strategy will be discussed in detail.
担当経験のある科目(授業)
1-
2005年6月 - 現在惑星大気科学特論 (総合研究)
Works(作品等)
2共同研究・競争的資金等の研究課題
15-
日本学術振興会 科学研究費助成事業 2023年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2018年4月 - 2021年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2012年4月 - 2015年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2010年4月 - 2014年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2008年 - 2010年
● 指導学生等の数
2-
年度2021年度(FY2021)修士課程学生数4受託指導学生数4技術習得生の数1
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年度2020年度(FY2020)修士課程学生数3受託指導学生数3技術習得生の数2
● 専任大学名
1-
専任大学名総合研究大学院大学(SOKENDAI)
● 所属する所内委員会
3-
所内委員会名理学委員会
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所内委員会名観測ロケット専門委員会
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所内委員会名スペースチェンバー専門委員会