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令和4年度宇宙輸送シンポジウム（2023年1月12日-13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 FY2022 (January 12-13, 2023. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, In order to achieve stable offshore rocket launches, we have launched small rockets from a small float anchored at sea and measured the dynamic behavior of the launch angle against wave motion. In this study, we propose a control model that performs angle control to cancel out the measured sway, and have created a control device that can control the launch angle of the launcher installed on the small float. Here, we report on the application of the control results to larger launch equipment., 資料番号: SA6000184009, STCP-2022-009

大気球シンポジウム 2022年度（2022年11月7-8日. ハイブリッド開催（JAXA相模原キャンパス& オンライン)), Balloon Symposium 2022 (November 7-8, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000177037, レポート番号: isas22-sbs-037

Biopauseプロジェクトでは、地球生命圏の上端“biopause”を理解するために成層圏微生物の採取実験を行っている。我々が新規開発した世界初の降下式インパクター型試料採取装置を搭載したJAXA（宇宙航空研究開発機構）の大気球を用いた第一回目となる2016年度実験では、成層圏微粒子の採取に成功した。次のステップとして、成層圏微生物の鉛直分布を把握するため、同時同地点異高度における試料採取を2017年度、並びに2019年度大気球実験にて行った。また、成層圏における培養可能な微生物と非培養な微生物の比率を推定し先行研究との定量的な比較を行うため、培養法分析も同時に行った。実験が成功した2019年度実験の結果から、非培養性微生物を含めた成層圏由来の微生物は一切検出されず、実験時における採取高度では微生物の存在量が検出限界未満であったことが示された。本稿では、2017年度と2019年度にJAXA共同利用実験として実施された本プロジェクトの大気球実験の概要とその分析結果について報告する。, The aim of Biopause project is to conduct a sequence of bioaerosol sampling in the stratosphere, in order to determine the location of ''biopause'', the upper boundary of the biosphere. By using JAXA's scientific balloons equipped with our newly developed world's first descending inertial impactor-style sampling device, we managed to collect some stratospheric bioaerosols in 2016. For the next step, to understand a vertical distribution of those stratospheric bioaerosols, we conducted the simultaneous bioaerosol sampling at the same location different altitudes in 2017 and 2019. We also carried out the cultivation analysis to have a quantitative comparison between culturable and unculturable stratospheric microorganisms. The results of a successful experiment in 2019 show the collection of zero number of bioaerosols including unculturable stratospheric microorganisms, which indicates the number of microorganisms at that time and altitudes of sampling was below the detection limit of our experimental methods. In this paper, we report the results from both balloon experiments of the Biopause project in 2017 and 2019., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2030024001, レポート番号: JAXA-RR-20-009

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), 資料番号: SA6000173004, STCP-2021-004

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), 資料番号: SA6000173024, STCP-2021-024

大気球シンポジウム 2021年度（2021年11月1-2日. オンライン開催), Balloon Symposium 2021 (November 1-2, 2021. Online Meeting), PDF再処理の為、2023年3月24日に差替, 資料番号: SA6000166013, レポート番号: isas21-sbs-013

大気球シンポジウム 2021年度（2021年11月1-2日. オンライン開催), Balloon Symposium 2021 (November 1-2, 2021. Online Meeting), 著者人数: 18名PDF再処理の為、2023年3月24日に差替, 資料番号: SA6000166029, レポート番号: isas21-sbs-029

This work synthesized oxygen sensitive and near infrared (NIR) luminescent Yb(III) coordination polymers incorporating ligands based on pyrene derivatives: Yb(III)-TBAPy and Yb(III)-TIAPy (TBAPy: 1,3,6,8-tetrskis(p-benzoate)pyrene, TIAPy: 1,3,6,8-tetrakis(3,5-isophtalic acid)pyrene). The coordination structures of these materials were characterized using electrospray ionization mass spectrometry, X-ray diffraction and thermogravimetric analysis, while the porous structure of the Yb(III)-TIAPy was evaluated based on its adsorption isotherm. The NIR luminescence properties of the Yb(III)-TBAPy and Yb(III)-TIAPy were examined by acquiring emission spectra and determining emission lifetimes under air, argon and vacuum. The Yb(III)-TIAPy exhibited high thermal stability (with a decomposition temperature of 400 °C), intense luminescence (with an emission quantum yield under argon of 6.6%) and effective oxygen-sensing characteristics. These results suggest that NIR luminescent Yb(III) coordination polymers made using pyrene derivatives could have applications in novel thermo-stable oxygen sensors.

大気球シンポジウム 2020年度（2020年11月5-6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, Balloon Symposium 2020 (November 5-6, 2020. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 18名, 資料番号: SA6000151019, レポート番号: isas20-sbs-019

第3回ハイブリッドロケットシンポジウム(2020年11月27日. オンライン開催), 3rd Hybrid Rocket Symposium(November 27, 2020. Online Meeting), 資料番号: SA6000172005, HR-2020-05

2019年度衝撃波シンポジウム (2020年3月4日-6日. 神戸大学 海事科学研究科（深江キャンパス)）神戸市, 兵庫県, Symposium on Shock Waves in Japan, FY2019 (March 3-4, 2020. Kobe University), Kobe, Hyogo Japan, 2019年度衝撃波シンポジウムは、新型コロナウイルスの感染拡大防止のため開催中止, 資料番号: SA6000148082, レポート番号: 3A2-2

地球生命圏の上端biopause、あるいは地球/地球外間の生命の流入/脱出の有無を確認することは、生命の普遍性や起源、進化､分布を理解する上で非常に重要である。地球/地球外間の生命の流入/脱出の有無を確認する最も直接的な鍵は地球中層大気での生物分布にある。我々は中層大気中での微生物の動態を包括的に理解するため、JAXA（宇宙航空研究開発機構）の大気球を用いた成層圏微生物採取実験（Biopause プロジェクト）を行っている。2016 年度に行った第一回目の大気球実験では、新規開発した降下式インパクター型試料採取装置を用いた、成層圏微粒子の採取に成功した。また、培養できないものも含めた成層圏微生物数密度の上限値を世界で初めて観測することに成功した。本稿では、第一回目の大気球実験の概要と初期分析の結果を報告する。, The location of 'biopause', the upper boundary of the biosphere, and the biological flux across the biopause on Earth are the key to understand the universality and distribution as well as the origin and evolution of life in the universe. The most direct information to elucidate the biopause is the distribution and dynamicity of life in the middle atmosphere. We carried out a scientific project named 'Biopause' using JAXA's scientific balloons in order to grasp the dynamics of biological flux in the stratosphere, i.e. the lower middle atmosphere, comprehensively. Our first balloon experiment was conducted on June 8, 2016 and collected aerosol particles in the stratosphere using a newly developed descending inertial impactor. We estimated the number density of the stratospheric microbes including the unculturable ones for the first time in the world. In this paper, we summarize the balloon experiment and the initial results of the sample analysis., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1730017002, レポート番号: JAXA-RR-17-007

大気球シンポジウム 2019年度（2019年11月7-8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, Balloon Symposium 2019 (November 7-8, 2019. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 17名, 資料番号: SA6000140002, レポート番号: isas19-sbs-002

大気球シンポジウム 平成30年度（2018年11月1-2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, Balloon Symposium 2018 (November 1-2, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 17名, 資料番号: SA6000128022, レポート番号: isas18-sbs-022

Accepted: 2015-05-21, 資料番号: SA1150104000

第18回宇宙科学シンポジウム (2018年1月9日-10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, 18th Space Science Symposium (January 9-10, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 19名, 資料番号: SA6000118077, レポート番号: P-044

大気球シンポジウム 平成29年度（2017年11月9-10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, Balloon Symposium 2017 (November 9-10, 2017. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 20名, 資料番号: SA6000103002, レポート番号: isas17-sbs-002

大気球シンポジウム 平成28年度（2016年11月1-2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, Balloon Symposium 2016 (November 1-2, 2016. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 20名, 資料番号: SA6000057008, レポート番号: isas16-sbs-008

大気球シンポジウム 平成28年度（2016年11月1-2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, Balloon Symposium 2016 (November 1-2, 2016. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000057030, レポート番号: isas16-sbs-030

平成27年度宇宙科学に関する室内実験シンポジウム (2016年2月23日-24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, 2016 Symposium on Laboratory Experiment for Space Science (July 23-24, 2016. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000055007

第42回 月・惑星シンポジウム(2009年8月5-7日, 宇宙航空研究開発機構宇宙科学研究本部), The 42nd ISAS Lunar and Planetary Symposium (August 5-7, 2009. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Sagamihara, Kanagawa Japan, We are developing a laser-induced breakdown spectroscopy (LIBS) system for future planetary exploration missions. LIBS can predict the elemental abundances of samples through analyzing acquired emission spectra. Analytical precision of LIBS depends on the spectral quality such as S/N ratio and wavelength resolution of the spectra. In this study we investigated the effect of S/N ratio and wavelength resolution on elemental abundance prediction when partial least squares regression (PLS) is used in spectra analysis. The results indicate that low-S/N ratio decreases the prediction precision. However, the prediction precision does not decrease even though the wavelength resolution is low enough that individual emission lines are not separated. This suggests that high-wavelength-resolution spectrometer is not required for LIBS system in using PLS, leading to decrease in the size and weight of LIBS system., 形態: CD-ROM1枚, 著者人数: 15人, Number of authors: 15, Note: One CD-ROM, 資料番号: AA0064739033

第42回 月・惑星シンポジウム(2009年8月5-7日, 宇宙航空研究開発機構宇宙科学研究本部), The 42nd ISAS Lunar and Planetary Symposium (August 5-7, 2009. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Sagamihara, Kanagawa Japan, Cyanide compounds are among the most important molecules in the chemical evolution phase of the origin of life. In our previous studies, we carried out laser ablation experiments within gas mixtures to simulate chemical reactions between impact-induced CN radicals and an ambient atmosphere after oblique impacts. We found that a large amount of cyanides are produced even within CO2-rich ambient gases. However, it is not clear how well laser-induced vapor plumes simulate vapor plume due to aerodynamic ablation of high-speed fragments from oblique impacts. In this study, we conducted hypervelocity oblique impact experiments in an N2 gas to compare the thermodynamic states of laser-ablation vapor and real impacts. Using high-speed spectroscopic measurements, the vibrational states and translational-rotational temperatures of impact-induced CN radicals are estimated. We found that the translational-rotational temperature of CN and C2 by impacts at ca.7 km/s of impact velocity was close to that by laser ablation with 9.0 x 10(exp 8)W/cm2 of laser intensity Experimental results indicate that laser ablation can simulate aerodynamic ablation process due to oblique impacts including vibrational non-equilibrium. This suggests that cyanide production efficiency estimated by laser ablation can apply to impact processes. Thus, impacts of C-rich meteorites may cause significant concentration of cyanide on the early Earth., 形態: カラー図版あり, 形態: CD-ROM1枚, Physical characteristics: Original contains color illustrations, Note: One CD-ROM, 資料番号: AA0064739034

著者人数: 22名, 資料番号: SA1002919000

The 41st ISAS Lunar and Planetary Symposium (August 6-8, 2008. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Laser-Induced Breakdown Spectroscopy (LIBS) has been proposed to measure the elemental compositions of rock samples on planetary surfaces. A problem of LIBS under a vacuum condition, however, is low spectral intensity. Thus, enhancement of spectral intensity is required for LIBS application to the surface analyses of the Moon and asteroids. We performed LIBS experiments at two pulse repetition rates under a vacuum condition in order to investigate its effects on total spectral intensity, the intensities of individual emission lines, and the accuracy of elemental analysis. The results indicate that a higher pulse repetition rate would yields a high accuracy in elementary analysis in lunar and asteroid explorations., Physical characteristics: Original contains color illustrations, 資料番号: AA0064291037

The 41st ISAS Lunar and Planetary Symposium (August 6-8, 2008. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Cyanide compounds are considered as one of the most important molecules in the chemical evolution phase of the origin of life. However, the production process of cyanides in the surface environment of early Earth is still highly uncertain. Recent experimental studies on hypervelocity impacts suggested that carbon-containing projectile efficiently interact with an ambient atmosphere during intense aerodynamic ablation in oblique impacts, leading to the production of CN radicals from carbon contained in the impactors and nitrogen in the ambient atmosphere. Nevertheless, the fate of CN radicals after the production is poorly understood. In this study, we conducted laser ablation experiments within gas mixtures of N2, CO2, and Ar to simulate the formation of the CN radicals by the hypervelocity oblique impacts and subsequent chemical reactions with the gas species in early Earth's atmosphere. We investigated the chemical composition and structure of the products condensed from laser－induced ablation vapors with graphite and cast iron targets using elemental analysis and infrared absorption spectroscopy. Our experimental results show that the amount of total nitrogen in the condensed material strongly depends on the composition of ambient gas mixtures, and reaches ca. 10 wt% in the products using nitrogen gas only. The depths of absorption bands of CN bonds increase with the partial pressure of N2 in ambient gas mixtures increases. These results indicate that laser-induced CN radicals are fixed into condensed products by generating CN bonds in its structure. Our results using cast iron targets also indicate that iron in the laser-induced ablation vapor helps the incorporation of CN radicals into the condensed materials. These experimental results suggest that the interaction between the carbon-containing impactors and the N2 atmosphere may supply complex cyanide compounds as condensed products to the primitive oceans and/or lakes of early Earth, which may played an important role in the origin of life., Physical characteristics: Original contains color illustrations, 資料番号: AA0064291038

Hydrogen CyaNide (HCN) is one of the most important molecules in the origin of life, and its production processes have been widely studied. However, the production rate of HCN in the early Earth is highly uncertain. Furthermore, it is estimated to be extremely low if the early Earth atmosphere is redox-neutral (i.e., N2-CO2 dominant). We focus on a CN radicals formation process due to hypervelocity oblique impacts as a new HCN production process, because this process may be able to produce HCN efficiently within an N2-CO2 dominant atmosphere. Impact-induced CN radicals may react with water vapor in an ambient atmosphere and generate HCN. However, these chemical reactions between impact-induced CN radicals and an ambient atmosphere have not been understood well. In our previous study, we conducted laser ablation experiments using graphite targets and N2-CO2-H2O-Ar model atmospheres to simulate chemical reactions between impact-induced CN radicals and a redox-neutral atmospheres. We found that laser-induced hot CN radicals convert to HCN efficiently in an ambient atmosphere containing as much as a few hundred mbar of CO2. However, empirical scaling rules on both vapor plume size and impact velocity are necessary to estimate HCN yield on actual impacts within the early Earth atmosphere because both actual and experimental pressure-temperature conditions of CN radicals are very different. Thus, we vary laser beam diameter and intensity to investigate the effects of vapor plume size and impact velocity on the conversion ratio from hot CN radicals to HCN molecules in this study. We found that the conversion ratio increases as beam diameter increases and that it decreases as beam intensity increases (i.e., impact vapor temperature increases). However, previous experiments show that the rate of increase in CN production as a function of impact velocity is higher than the rate of decrease in conversion ratio estimated by our laser experiments. These results strongly suggest that this HCN production process works efficiently on actual asteroidal impacts., 資料番号: AA0063723025

資料番号: SA1000117000

資料番号: SA1000130000

資料番号: SA1000131000

大気球シンポジウム 平成27年度（2015年11月5-6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, Balloon Symposium 2015 (November 5-6, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 22名ほか, 資料番号: SA6000044021, レポート番号: isas15-sbs-021

第48回月・惑星シンポジウム (2015年7月29-31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, 48th ISAS Lunar and Planetary Symposium (July 29-31, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000045009

平成26年度宇宙科学に関する室内実験シンポジウム (2015年2月23日-24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, 2015 Symposium on Laboratory Experiment for Space Science (July 23-24, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000076026

Hydrogen Cyanide (HCN) is considered as one of most important compounds for the origin of life because it is a precursor of complex organic molecules, such as amino acids and nucleic acid bases. Although a number of different mechanisms of HCN formation on the early Earth have been studied, HCN formation due to large impacts is particular important because it produces a large amount of HCN in a short period of time. We focus on the chemical interaction between impact-induced vapor clouds and a planetary atmosphere. Impact experiments by Sugita & Schultz (2000) show that a large amount of CN radicals may be produced by carbon-rich meteoritic material within a nitrogen-rich atmosphere. The produced CN radicals may react with water vapor in an ambient atmosphere and generate HCN. However, high-temperature CN may also destroy to CO and NO via chemical reactions with the ambient atmosphere. In this study, we conduct laser ablation experiments using a Gas Chromatograph Mass Spectrometer (GCMS) to examine whether impact-generated CN radicals lead to HCN formation. Graphite targets and gas mixtures of nitrogen and water vapor were used in our experiments. We found a strong correlation between the yield of HCN and the chemical composition of the model atmosphere. Although little HCN was detected in N2 atmospheres, a large amount of HCN was detected in a N2-H2O atmosphere. This result strongly suggests that impact-generated CN radicals may lead to HCN formation., 資料番号: AA0063505052

Gaseous species produced within impact-induced vapor clouds may have played an important role in surface environment of planets. However, the molecular composition of those gases is not known well. In particular, interaction between carbon compounds and silicates is poorly understood. In previous study, we confirmed experimentally that SiO2-derived oxygen reacts with carbon compounds under laboratory conditions. However, it is still not clear whether such oxidation processes occur in large planetary-scale impacts. In this study, we perform thermodynamic equilibrium calculation to assess whether the reactions between SiO2-derived oxygen and carbon compounds occur under planetary-scale impact conditions, which are characterized by various impact velocities and large scale. Our results show that large amount of SiC and/or gaseous SiO is produced at 1,000-2,000 K, where chemical reactions within planetary-scale impact-induced vapor clouds quench, regardless of impact velocity. The formation of SiC and/or gaseous SiO implies that the composition of resulting gas within planetary-scale impact-induced vapor clouds is oxidized by SiO2-derived oxygen regardless of impact velocity., 資料番号: AA0063350005

本研究では衝突クレーター形成実験を行い、放出破片の総質量を測定した。弾丸としてポリカーボネイト、標的の粒子として平均粒径200、80、40μmのガラスビーズを用いた。測定した総放出破片質量からトランジェントクレーターと総放出破片の体積関係(体積比)および掘削部分の深さ関係(深さ比)を明らかにした。体積比はトランジェントクレーターの大きさに依らず一定であるが、標的粒子の粒径に依存することがわかった。粒径200、80、40μmにおける体積比の平均値はそれぞれ0.36、0.27、0.18であった。深さ比もトランジェントクレータの大きさに依らず一定で、標的粒子の粒径に依存した。粒径200、80、40μmにおける深さ比の平均値はそれぞれ0.28、0.21、0.14であった。最後に体積比の結果を用いて、Z-modelのパラメーターであるZ値を導出した。Z値は標的粒子の粒径が小さくなるにつれて小さくなった。これらの結果より、掘削流のパターンが粒径により変わり、粒径が小さいほど掘削流は浅いことがわかった。, 資料番号: AA0046919023

There is measured the mass M(sub ex) (excavation mass) of materials excavated by impact on glass sphere targets with different grain sizes. The excavation mass M(sub ex) is shown to be nearly M(sub ex) proportional to nu (nu is projectile's impact velocity), while, it depends on the projectile mass m as followed: M(sub ex)/nu proportional to m(sup 0.6 to 0.8). The present results also show that the excavation mass depends on the target grain sizes., 資料番号: AA0047898004

Chemical reactions within impact-induced vapor clouds may have played an important role in both the evolution of atmosphere of the Earth and the origin of life. However, chemical reaction process within impact vapor clouds is not understood well yet. In particular, chemical interaction between silicates and carbon compounds has not been studied extensively. The thermal decomposition of silicates within impact vapor clouds may affect the carbon chemistry within impact vapor clouds. Laser irradiation experiments using terrestrial rocks and chondrites by Mukhin et al. (1989) show that the carbon-bearing gas produced in the laser heating experiments were composed mainly of the oxidized species, such as CO and CO2, with only small amounts of reduced species such as hydrocarbon, HCN, and CH3CHO. Mukhin et al. (1989) propose that oxygen derived from thermal decomposition of silicates may oxidize carbon. However, such an oxidation process has not been investigated in detail. Most theoretical studies on chemical reaction in impact vapor clouds neglected such an effect of oxygen released from silicates. In this study investigated quantitatively is the oxidation of carbon compounds by oxygen from SiO2 in vapor clouds using laser-pulse heating experiments., 資料番号: AA0047898009

Impact cratering experiments into soda-lime glass spheres were performed in order to investigate grain size dependence on formation process of transient craters when gravitational effects dominate over target, strength (gravity regime). Diameters and depths of transient craters for the target spheres with sizes of 50, 80, and 220 micrometer were measured. The rim diameters of the transient craters depend on the grain sizes, while the dependence in depths is small. The present data of the rim diameters of transient craters does not follow a simple power-law relation between scaled-crater radius and gravity-scaled size, which was suggested as the scaling law on crater sizes in the gravity regime (e.g., Schmidt and Housen 1987). The results may suggest that the scaling law in the gravity regime needs to take into account the effect of grain sizes., 資料番号: AA0046650069

資料番号: AA0046650052

資料番号: AA0046650019

Excavation flow in impact cratering has been usually modeled by Maxwells Z-model. However few laboratory experiments and/or numerical simulations have been done to examine whether or not the Z-model's streamlines actually express the excavation flow. A numerical simulation of impact onto granular materials by the Discrete Element Method (DEM) is suitable to trace directly the trajectories of target particles. Then a numerical code was developed to simulate impact onto granular materials. The results show that the target particles move along the Z-model's streamlines in the following cases: Z = 3 (effective origin of flow (EOF) is located at the target surface) or Z = 2.7 (EOF is located at the depth of one projectile radius). These results indicate that the Z-model is a reasonable first-order quantitative approximation for excavation flow in impact cratering process., 資料番号: AA0046650014

Fischer-Tropsch catalysis, in which CO and H2 are converted into CH4 over iron catalyst, has been suggested to play a key role in the circumplanetary nebula for the origin of CH4 in the atmosphere of Jupiter, Saturn and Titan. Experimentally investigated was the methane formation rate over iron catalyst under conditions similar to those within the circumplanetary nebula (P = 0.09-0.53 bar, T = 500-650 K, H2/CO = 1000). The results show that the methane production does not simply increase as the temperature rises predicted by the previous work, and it proceeds efficiently between T = 525 and 625 K. The results also suggest that the conversion of CO into CH4 in the circumplanetary nebula may proceed in short time and CH4-rich subnebula may be formed at early stage of its evolution. The organics, formed by the disequilibrating process from CH4, may affect the formation time of satellites and be supplied to the icy satellites., 資料番号: AA0046650005

第15回宇宙科学シンポジウム (2015年1月6日-7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, 15th Space Science Symposium (January 6-7, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 資料番号: SA6000034314, レポート番号: S3-001

大気球シンポジウム 平成26年度（2014年11月6-7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, Balloon Symposium 2014 (November 6-7, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 16名, 資料番号: SA6000021030, レポート番号: isas14-sbs-030

第47回月・惑星シンポジウム (2014年8月4日-6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, 47th ISAS Lunar and Planetary Symposium (August 4-6, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 形態: カラー図版あり, 資料番号: SA6000033029

平成25年度スペースプラズマ研究会 (2014年2月27日-28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, Space Plasma Conference FY2013 (February 27-28, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 資料番号: SA6000077034

大気球シンポジウム 平成25年度（2013年11月14-15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), Balloon Symposium 2013 (November 14-15, 2013. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 15名, 資料番号: SA6000065030, レポート番号: isas13-sbs-030

第46回月・惑星シンポジウム (2013年8月5日-7日. 宇宙航空研究開発機構宇宙科学研究所), 相模原市, 神奈川県, 46th ISAS Lunar and Planetary Symposium (August 5-7, 2013. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 形態: カラー図版あり, 形態: CD-ROM1枚, 資料番号: SA6000015017

大気球シンポジウム 平成24年度（2012年10月16-17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), Balloon Symposium 2012 (October 16-17, 2012. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000066037, レポート番号: isas12-sbs-037