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令和4年度宇宙科学に関する室内実験シンポジウム（2023年3月6日-7日. オンライン開催), 2023 Symposium on Laboratory Experiment for Space Science (March 6-7, 2023. Online Meeting), 資料番号:SA6000187010, レポート番号: 10

令和3年度宇宙科学に関する室内実験シンポジウム（2022年2月28日-3月1日. オンライン開催), 2022 Symposium on Laboratory Experiment for Space Science (February 28-March 1, 2022. Online Meeting), 資料番号: SA6000178015, レポート番号: 15

Additional file 2: Additional_figure_file1. Spectra of the stars obtained by comparing their observed count profiles as functions of wavelength with that of α And. See the text in the file for details.

Additional file 1: Additional_video_file. Flash candidate 170201. We converted successive ten frames in a raw SER format video file to FITS format images. Then, we increased the brightness and contrast of these images with fixed parameters. Next, we made an animated GIF file of 5 frames s−1 in framing rate with these images. Finally, we pasted the animation on the PowerPoint slide.

第22回宇宙科学シンポジウム (2022年1月6日-7日. オンライン開催), 22nd Space Science Symposium (January 6-7, 2022. Online Meeting), 著者人数: 17名, 資料番号: SA6000176050, レポート番号: P-013

Additional file 3: Additional_figure_file2. Lightcurves of the three flashes that lasted more than a video frame. See the text in the file for details.

令和2年度宇宙科学に関する室内実験シンポジウム（2021年3月5日. オンライン開催), 2021 Symposium on Laboratory Experiment for Space Science (March 5, 2021. Online Meeting), PDF再処理の為、2023年3月7日に差替, 資料番号: SA6000161036, レポート番号: 36

令和元年度宇宙科学に関する室内実験シンポジウムは、新型コロナウイルスの感染拡大防止のため開催中止。すべて書面発表になりました。, 資料番号: SA6000149002, レポート番号: 2

EQUULEUS is a spacecraft to explore the cislunar region including the Earth-Moon Lagrange point L2 (EML2) and will be launched by NASA’s SLS EM-1 rocket. Although the size of EQUULEUS is only 6U, the spacecraft carries three different science instruments. By using these instruments, the spacecraft will demonstrate three missions for solar system exploration science during and after the flight to EML2; imaging of the plasmasphere around the earth, observation of space dust flux in the cislunar region, and observation of lunar impact flashes at the far side of the moon. The developments and verifications of the flight models of these science instruments were completed by the end of 2018, and we started flight model integration and testing. This paper introduces the details of the scientific objectives, design results and development statuses of the instruments. In addition, results of the integration and pre-flight tests are also described.

平成30年度宇宙科学に関する室内実験シンポジウム (2019年2月28日-3月1日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 2019 Symposium on Laboratory Experiment for Space Science (February 28 - March 1, 2019. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000139023

第50回月・惑星シンポジウム (2017年8月3-4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, 50th ISAS Lunar and Planetary Symposium (August 3-4, 2017. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000200002

第7回スペースデブリワークショップ (2016年10月18-20日. 宇宙航空研究開発機構調布航空宇宙センター(JAXA)(CAC)), 調布市, 東京, The 7th Space Debris Workshop (October 18-20, 2016. Chofu Aerospace Center, Japan Aerospace Exploration Agency (JAXA)(CAC)), Chofu, Tokyo, Japan, スペースデブリの総数が年々増加し、積極的な除去が必要な状況になっている。宇宙航空研究開発機構(JAXA)では、スペースデプリ除去のための推進系として導電性テザー推進(EDT推進)の研究を進めている。これまでテザー数値シミュレーションにおいて、テザー引張時には力と伸びが比例せず、圧縮時にはパネカが働かない非線形バネモデルとして扱ってきたが、実際のテザーは塑性域まで引張された場合、塑性変形を起こし残留歪みが生じる。そこで、本研究ではテザーの残留歪みを検証するために実験を行い、残留歪みを考慮した非線形バネモデルを作成した。そして、特に残留歪みの影響が確認できる伸展急停止時において数値計算を行い、テザーのダイナミクスとエンドマスの挙動から残留歪みの影響を評価した。, As a countermeasure for suppressing space debris growth, the Japan Aerospace Exploration Agency (JAXA) is investigating an active space debris removal system that employs highly efficient electrodynamics tether (EDT) technology as its orbital transfer system. In numerical simulation to evaluate the tether dynamics, tether has been modeled as point masses connected by nonlinear springs and viscous dampers. The model is not considered the residual strain which occur on the actual tether at plastic deformation. In this paper, a nonlinear model considering residual strain is developed based on the results of tensile tests. Then, numerical simulations are conducted to investigate the effects of nonlinearity and residual strain. The results confirm that it is necessary to consider the nonlinearity and the residual strain in the numerical simulation when strong tension is applied on the tether such as in the case of unintentional stopping of tether deployment at a short length., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1630052050, レポート番号: JAXA-SP-16-011

We have developed railgun system since 1986 for the research on hypervelocity impacts in space. Three railguns with barrel length of 95 cm, 165 cm and 186 cm are used for the experiment. 95 cm railgun has 10 mm square bore, 165 cm and 186 cm railguns have round bore with 13 mm diameter. Projectile is polycarbonate block and its mass is 1.0-2.0g. A power supply is 6 mF capacitor bank. Total maximum energy is 300 kJ. The power supply is constituted by a 6 stage pulse forming network, a pulse transformer, a main switch and a crowbar switch. The current waveform may be controlled by varying the inductor of pulse forming network. The highest projectile velocity achieved in our institute is 4.8 km/sec., 資料番号: SA0033442000

The railgun system was set up in the Institute of Space and Astronautical Science (ISAS) and about a hundred shots were carried out preliminarily in 1986. The following four methods of projectile velocity measurement were tried in the experiments. (1) laser fence, (2) magnetoflyer, (3) wire cut, (4) thin plate The third method appeared to be the simplest and most reliable one, while the laser fence was affected severely by the dust and plasma which were blown off with the projectile. The second and fourth ones suffered the electromagnetic noise. The wire cut would be the best way just to measure the velocity itself, but it affects the projectile attitude and its front surface. For the railgun application, the improvement of the laser fence method or ones with X-ray, which have no effect on the projectile, would be neccesary., 資料番号: SA0166213000

レールガンにおいてprojectileの後ろに銅, タングステン, タンタル等の金属片を接着し, 発射実験をおこない, 得られた速度, 効率を比較した。銅片を厚くすると速度は低くなるが, 効率は上がっていくという結果が得られた。厚さ5mmのタングステン, タンタル, 銅片を比較してみると効率は高い方からタングステン, タンタル, 銅の順区であった。また, 効率はprojectileの質量と関係が深いことがわかった。これらの結果から, 金属片を接着すると効率が上がる理由について論じている。, The chips of copper, tugsten, tantalum were attached to the projectiles, which were used in the railgun experiments. The thicker copper chip was used, the lower the velocity became, but the higher the efficiency became. The highest efficiency of the chips 5mm thick was gotten when the tungsten chip was used. The second was tantalum and the third was copper. The results show that the efficiency has relations with projectile mass. The reasons why the thicker copper chips made the efficiency higher and why tungsten and tantalum made the efficiency higher are discussed., 資料番号: SA0166214000

資料番号: SA0034906000

The background pressure for the SEPAC experiments (Space Experiments with Particle Accelerators) was monitored by the vacuum gauge on the Spacelab pallet. The pressure during the whole mission shows a clear relationship with the orbiter's velocity vector. When the gauge is screened by the orbiter from the relative flow of the upper atmosphere (wake condition), the pressure is constantly low, but much higher than that of the model atmosphere. At present, it is best explained by gas leakage from Spacelab or some of its instruments. When the gauge is open to the flow (ram condition), the pressure is linearly related to the cosine of the incident angle and has a maximum at normal incidence. The maximum is more than one order of magnitude higher than the model pressure. This is interpreted as escape of incident atmosphere from the Spacelab's surface with thermal velocity., 資料番号: SA0034997000

This paper describes various characteristics of the magnetospheric field, induction field, and ionospheric field observed by MAGSAT (Magnetic Field Satellite) and the derivation of crustal magnetic anomalies free from disturbance fields. After eliminating the effect of the disturbance field, anomaly maps were derived for the Japanese area and for the Shatsky Rise area. The magnetic field observed by satellites consists of a core field, induction field, crustal field, ionospheric field, and magnetospheric field. To derive the anomalies of crustal origin of a few to a few tens of nanoteslas (nT) in its magnitude, the other fields (which amount even to several tens of thousands of nT) must be excluded from the observed data. It has already been shown that the core field is well approximated by a model with spherical harmonics up to the 13th degree and order. On the other hand, the induction field, ionospheric field, and magnetospheric field observed by a low-altitude satellite in the middle and low latitude region have not been studied in detail. Therefore, the corrections for these fields used to be empirical without a firm physical basis. The analysis of the MAGSAT data during substorms with high Kp-indices shows a noticeable dawn-dusk asymmetry of the Dst field, i.e., decrease of the horizontal component of the geomagnetic field is much more pronounced on the duck side than on the dawn side. This fact indicates that an anti-sunward net field aligned current in the magnetosphere is responsible for the dawn-dusk asymmetry of the Dst field. Spherical harmonic expansion of the magnetospheric field, induction field, and ionospheric field shows that the first degree term could well approximate the magnetospheric field and induction field. Hence, these fields can easily be excluded by the subtraction of the best-fitted first degree spherical harmonic fields. The spherical harmonic expansion of the observed magnetic field also shows that the ionospheric field has small-scale structure. The structure for the dawn side is different from that for the dusk side. Conventional path-to-path correction would not be appropriate to exclude the field of ionospheric origin. By taking an average of the ionospheric field at the same local time and dip latitude, we obtain the Mean Ionospheric Fields (MIF) as functions of dip latitude for the dawn side and dusk side separately. The subtraction of the Mean Ionospheric Field could exclude the effect of ionospheric current (Mean Ionospheric Field Correction, MIFC). The difference in the structure between the dawn and dusk side disturbance field was used to evaluate how perfectly the magnetospheric fields, induction field, and ionospheric field had been removed. It was shown that the Mean Ionospheric Field Correction (MIFC) was better than other conventional corrections. By means of the Mean Ionospheric Field Correction, anomaly maps have been prepared for the area around Japan and the Shatsky Rise. The close resemblance between the dawn side and dusk side anomalies suggests that the maps are almost completely free from the effect of the induction, ionospheric, and magnetospheric fields., 資料番号: SA0034956000

The two stage light gas guns have been used widely to study the collisions between planetesimals, from which the planets were believed to be made, meteorite impacts on the surface of the moon and planets, and high pressure states in the planetary interiors. The electromagnetic guns, especially railguns, are expected to make these researches with much higher velocity (more than 10km/sec) possible. The railgun accelerator system was set up in the Institute of Space and Astronautical Science (ISAS) in 1986,having more than 10km/sec with 1g projectile as a goal. The energy source is a 300kJ capacitor bank. The maximum velocity so far is 2.4km/sec at 108kJ with 2.4g projectile and 1.8m barrel., 資料番号: SA0166212000

著者人数：17名, Accepted: 1984-05-10, 資料番号: SA1001644000