We had realized the composition gradient of elements or isotopes in some binary alloys or single element by solid-state centrifugation. While, it might difficult to realize graded structure of elements in binary ionic crystal by centrifugation as it strongly keeps their stoichiometry. However, isotope fractionation in binary ionic crystal by centrifugation might be expected as the self-diffusion of ions occurs. We have planed the ultracentrifuge experiments on α -AgI superionic conductor to investigate the isotope effect in binary ionic crystal under a strong centrifugal acceleration field. α -AgI superionic conductor is suitable for the confirmation experiment as it is an intrinsic ionic crystal and Ag ions have high diffusivity. For the first stage, we have experimentally searched the experimental conditions of magnitude of centrifugal acceleration and temperature that ensure the experiment without decomposition. It is confirmed that the combination of experimental conditions of up to 6.1x10⁵ g, 350°C, 24h ensure the experiment without decomposition at least.

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Recent progress in research on Laser Space Solar Power Systems (L-SSPS) is described. In the laser transmission system, safe connection between transmitter and receiver is of primary focus. Development and experimental demonstration of a safe connection in a sub-kilometer terrestrial transmission site is presented based on beacon tracking technology. Atmospheric influences on laser transmission for the L-SSPS are studied. Atmospheric transmittance is derived from meteorological data of solar irradiation in Japan. Using the analyzed data, the site diversity effect is described. In addition, a prediction model using a simulation developed at Gifu University based on a 5th generation Mesoscale Model is presented. A transmittance distribution map of the Japan region for the laser wavelength of interest is made for the first time from the model. In laser photovoltaics, optical properties and photovoltaic conversion efficiency of CPV-Si and InGaAs cells under 1.07 μm laser irradiation are measured and discussed for efficient power conversion from laser light to electricity.

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Solar Power Sail is a novel spacecraft with hybrid propulsion of large-area solar sail and electric propulsion driven by thin-film solar panel. The Solar Power Sail spacecraft is currently developed to probe into the outer-solar system bodies out to the Jupiter orbit, which was not well precedently explored. This mission aims to explore Trojan asteroids and interplanetary dusts by remote sensing and in-situ sampling using orbital rendezvous or fly-by technique. Scientific objective of this mission is not only planetary science but also novel astronomy; measurement of the infrared extragalactic background light without foreground contamination of the zodiacal light thanks to low-density environment at deep space, polarization measurement of the gamma-ray burst and accurate determination of its direction based on the interplanetary network technique. The Solar Power Sail mission will thus develop a new direction of space astronomy and planetary science providing us an interplanetary telescope site and will play an important roll to form a new interdisciplinary science field.

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A customized lightweight and low-power radiation micro-tracker has been constructed for the microsatellite RISESAT (Rapid International Scientific Experiment Satellite) developed by Tohoku University for scientific experiments in space. The instrument is based on hybrid semiconductor pixel detector technology developed by the Medipix Collaboration. These Timepix detectors consist of an array of 256 × 256 (= 65 k) pixels with 55 μm pitch distributed over area of 2 cm². Each cell is connected to the corresponding pixel on the 300 μm thick siliconsensor. Each pixel integrates electronics which enables counting of the number of particles, to measure the energy deposited or to register the time of interaction of ionizing particles per-pixel. Two independent detector layers operate as a radiation micro-telescope and provide high resolution and high sensitivity tracking and directional detection of energetic charged particles (electrons, muons, pions, protons, light ions up to heavy and relativistic ions). Also X-rays and even neutrons can be detected. The pixel detectors provide noiseless detection of single radiation quanta, measure their energy, position, direction of trajectory and time of interaction. Different types of particles and interactions can be identified and distinguished thanks to the detector's high spatial granularity.

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The cosmic radiation field in space is rather complex in terms of composition and with respect to energy of the constituent particles. The intensity and energy spectrum of the cosmic radiation may considerably change with time as well. A three dimensional silicon detector dosimetry telescope (TRITEL), with sensitivity in 4π, has been recently developed in the Centre for Energy Research, Hungarian Academy of Sciences. The instrument comprises three mutually orthogonal, fully depleted, passivated implanted planar silicon detector pairs and it is designed to measure the energy deposit of charged particles. From the time spectra and the deposited energy spectra measured, the flux of charged particles, the absorbed dose, the linear energy transfer (LET) spectra and the average quality factor of the cosmic radiation, as well as the dose equivalent can be determined. This way the stochastic biological effects of the cosmic radiation in orbit can be characterized. Measurements have been already performed in the stratosphere on research balloons and on board the International Space Station (ISS). The orbit of RISESAT (Rapid International Scientific Experiment Satellite) gives an excellent opportunity to measure the dosimetric quantities listed above at higher altitudes and higher latitudes than at which the ISS is orbiting around the Earth.

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The Small Demonstration Satellite-4 (SDS-4) of JAXA launched on May 18, 2012 (JST) is equipped with a Japan's first quartz crystal microbalance (QCM) for spacecraft surface contamination monitoring. The QCM was installed on one of the satellite outer surface and occasionally observed gradual frequency decrease (=contamination) under the ground clean room environment for about a year. The QCM frequencies just before and after the launch by the H-IIA Launch Vehicle No. 21 (H-IIA F21) were almost the same, which indicated good cleanness inside the H-IIA's payload fairing. The frequency rapidly increased to the initial level during the first week after the launch probably due to removal or erosion of contaminants on the crystal surface by attack of atoms and ions in the orbit at an altitude of about 700 km. Contamination was never dominant during seventeen months of the space operation. Long term trend of the QCM frequency seems to be affected by the upper atmosphere density changing with the F10.7 solar radio flux.

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A Coulomb force attractor is studied for orbital deflection of potentially hazardous asteroids. The concept of a Coulomb force attractor is based on towing an asteroid by utilizing the mutual gravitational force and Coulomb force, induced by artificial charging, between a spacecraft and the asteroid. Particular attention is placed on evaluating the resulting change in the asteroid orbit. The electric potential distribution around the spacecraft is studied, and an analytic expression of the mutual Coulomb force is derived. The equations of motion are derived for a rotating reference frame, and the performance of the Coulomb force attractor is investigated through numerical simulation. The differences between a Coulomb force attractor and a traditional gravity tractor are also examined, and the concept of asteroid towing using several spacecraft is proposed.

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JAXA already has the spacecraft design standard, JERG-2-000. Although this is useful, the document structure is not systematized or managed as a system with weekly controls which leads to a lack of completeness of coverage and to duplicated requirements. Additionally, the organizational system to maintain the standards is not yet fully developed. This paper proposes a spacecraft design standard architecture for organizational knowledge creation. It consists of a systematized document structure system based on the Dual Vee model and an organizational system based on the SECI model which can exchange the tacit knowledge of individuals such as know-how or experience. Effectiveness is verified by application to JERG-2-130 GENERAL TEST STANDARD.

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The H-II Transfer Vehicle (HTV) was developed from 1997 to 2013, a period when the number of experienced engineers declined due to transfer and retirement. This led to a loss of organizational knowledge that will detrimentally affect future large-scale projects. While there is a general awareness of this situation, no formal assessment has been made to facilitate its visualization, a lack which this study addresses. The current knowledge situation and the awareness of HTV development are visualized on the basis of a questionnaire responded to by JAXA and contract engineers. The results show a gradual loss of knowledge, together with a loss of the ability to sustain institutional knowledge, while budgetary limitations make it difficult to launch large projects. In this environment, individual engineers tend not to hand down their knowledge and experience, accordingly, a systematic institutional program to improve this situation is identified as an important subject for future study.

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The authors have established a systems engineering (SE) and project management (PM) educational program for university students developing a 1kg-class simulated-satellite, called CanSat. The educational program helps students achieve mission success through the practical application of SE/PM methodologies to their development processes. In the educational program, the students are advised by young professionals currently working as aerospace engineers. In this study, one team was taken as a case study to evaluate the SE/PM educational program; the results showed that cooperative activities between students and young professionals were critical to the effectiveness of the SE/PM education.

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In order to reduce steps in developments of spacecraft and onboard instruments, we developed two tools SIB2PlanEditor and SIB2Viewer. SIB2PlanEditor is dedicated editor for test procedure described in the ISAS command plan language. SIB2Viewer is a program to enhance capability of user interface for SIB2 (SIB2UI). Both tools reduce simple work in developments and contribute designer of spacecraft and onboard instruments to concentrate on preparation of content of test procedure and design itself. This paper describes function of these tools and evaluated merits through trial usage. By usage of SIB2PlanEditor, time needed for input of test procedure is reduced by factor 1/3~1/2. These tools are also expected to contribute to reduce time of execution of electrical integration and test of the spacecraft through promotion of SIB2 input in earlier stage of the development.

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This paper will examine applied usages of popular culture works in the classroom for the execution of innovative programmes and will also serve as a progress report on the ongoing course at the Meiji University School of Commerce, titled “Introduction to Astrosociology”, part of the Special Themed Activity Classes (Tokubetsu-teema jissen kamoku). For this purpose I will describe my own lesson plan and ultimately illustrate the importance of not only the usefulness of these works as tools for education, but also the issues which they bring to the mind of the young individual living in our current postmodern age.

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Revelations surfaced publicly in November 2011 that unknown hackers had over 2007-8 breached the command links to both Landsat 7, and NASA's Terra EOS AM-1, and, on June 20, 2008 “achieved all steps required to command” Terra. In February 2012, NASA reported to U.S. Congress a list of pervasive and deep-seated cybersecurity problems, confirming that hackers had gained access to and downloaded sensitive data from several of the agency's major centers. While attention on satellite security currently and rightly focuses more traditional threats to space systems, the issue of cyber security is now a major concern. Following a summary of some of the main suspected cases of known significant cyber attacks on several space agencies, highlighting the findings of the NASA report, this paper shows that sophisticated APTs are presenting a new and major threat to data assurance and space systems and analyses the response of NASA, ESA and JAXA to the issue, concluding that cyber security concerns are presenting new challenges and forcing new policy initiatives by space asset holders.

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This paper provides an outline of Mitsubishi Electric Corporation (MELCO)’s system safety management for satellites and provides some examples according to its framework. Risk assessment, safety design order of precedence, and frequent communication and knowledge management based on the Plan-Do-Check-Act cycle are the crucial success factors of system safety management.

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