The regenerative cooled LOX/methane engine is considered by the cooperative research with JAXA, MHI, and IHI. As a part of this cooperation, the experiments and analysis about LOX/methane combustion instability and regenerative cooling characteristics were carried out because the lack of the fundamental LOX/methane properties was identified as a risk through engine design, production, test, and operation.

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A 30-kN rocket engine, a pilot engine, is being developed in Japan. Development of this pilot engine has been initiated in relation to a reusable sounding rocket, which is also being developed in Japan. This rocket takes off vertically, reaches an altitude of 100 km, lands vertically at the launch site, and is launched again within several days. Due to advantage of reusability, successful development of this rocket will mean that observation missions can be carried out more frequently and economically. In order to realize this rocket concept, the engines installed on the rocket should be characterized by reusability, long life, deep throttling and health monitoring, features which have not yet been established in Japanese rocket engines. To solve the engineering factors entitled by those features, a new design methodology, advanced engine simulations and engineering testing are being focused on in the pilot engine development stage. Especially in engineering testing, limit condition data is acquired to facilitate development of new diagnostic techniques, which can be applied by utilizing the mobility of small-size hardware. In this paper, the development status of the pilot engine is described, including fundamental design and engineering tests of the turbopump bearing and seal, turbine rig, injector and combustion chamber, and operation and maintenance concepts for one hundred flights by a reusable rocket are examined.

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The third-generation vehicle RVT#3 equipped with a pressure-fed engine, which had upgraded in terms of durability enhancement and a LH₂ tank of composite material, successfully performed in repeated flight operation tests; and the vehicle reached its maximum flying altitude of 42m in October 2003. The next step for demonstrating entire sequence of full-scale operation is to put a turbopump-fed system into propulsion system. From a result of primary system analysis, we decided to build an expander-cycle engine by diverting a pair of turbopumps, which had built for another research program, to the present study. A combustion chamber with long cylindrical portion adapted to the engine cycle was also newly made. Two captive firing tests have been conducted with two different thrust control methods, following the component tests of combustor and turbopumps separately conducted. A considerable technical issues recognized in the tests were the robustness enhancement of shaft seal design, the adjustment of shaft stiffness, and start-up operation adapted to the specific engine system. Experimental study of GOX/GH₂ RCS thrusters have also been started as a part of a conceptual study of the integration of the propulsion system associated with simplification and reliability improvement of the vehicle system.

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Recently, the new design method is required to predict "system reliability level" at the conceptual design phase, to grasp and to optimize the distribution of "risks and margins" because attainable "system reliability level" strongly depends on its basic concept. This paper describes a sample approach to measure "system reliability level", focusing on analytical modeling of failure mechanism and rocket engine steady-state or dynamic simulator. Some design parameters are picked up to understand where and how their dispersion makes an effect in the whole engine system performance or reliability, and to control the total system robustness.

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Institute of Space and Astronautical Science of Japan Aerospace Exploration Agency (ISAS/JAXA) successfully developed and operated the microwave discharge ion engines “µ10” onboard Hayabusa asteroid explorer. The µ10 ion engines feature the cathode-less plasma generation in both the ion sources and neutralizers with the results of long life and high reliability in space. Based on the space achievements of µ10 ion engines with 8mN thrust, 3,000sec Isp and 350W consumption power, the µ10HIsp is under development for deep space missions to such as Jupiter and Mercury. The integrated test with the plasma sources, a propellant isolator, a microwave DC block and a high Isp grid system established the thrusting operation with 9,600sec Isp using 15kV acceleration voltage, 25mN thrust, 12mN/kW thrust power ratio, and 2.1kW power consumption.

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More than three decades of experience have been gained in the field of electric propulsion at the Institute of Space Systems (Institut für Raumfahrtsysteme = IRS). Recent developments within the field of electric propulsion are summarized and foremost results are highlighted. The various types of electric propulsion systems are not considered as to be competitive. Here, system analysis shows that optimum parameter such as the required exhaust velocity or specific impulse result taking into account both the mission profile and system related sizes such as the power conditioner efficiency, the thrust efficiency and the specific mass of the corresponding power unit. Correspondingly, ion thrusters, Hall thrusters, thermal arcjets, or magnetoplasmadynamics (MPD) thrusters are preferable depending on the mission. Among the described electric propulsion systems are recent developments in the field of applied field MPD but also from high power hybrid thrusters. In addition, new concepts such as the hybrid systems Thermal-Inductively heated Hybrid-Thruster of the University of Stuttgart (TIHTUS) and the so-called Coupled Tether/Ion Engine Propulsion (CETEP) are analysed.

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Currently, the solar battery, the chemical cell, and the RI battery are used for the energy source in space. However, it is difficult for them to satisfy requirements for deep space explorations. Therefore, other electric power sources which can stably produce high electric energy output, regardless of distance from the sun, are necessary to execute such missions. Then, we here propose small nuclear reactors as power sources for deep space exploration, and consider a conceptual design of a small nuclear reactor for Nuclear Electric Propulsion System. It is found from nuclear analyses that the Gas-Cooled reactor could not meet the design requirement imposed on the core mass. On the other hand, a light water reactor is found to be a promising alternative to the Gas-Cooled reactor.

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An overview is given on a numerical simulation program for applied field magnetoplasmadynamic (AF-MPD) thrusters, which is currently under development at the Institute of Space Systems (IRS). The program allows the simulation of argon plasma flows in thermal and chemical non-equilibrium. The code is based on an axisymmetric finite volume method on unstructured, adaptive meshes. An externally applied magnetic field can be taken into account employing the vector potential formulation. Azimuthal velocity and magnetic field are handled by a quasi three-dimensional approach with vanishing azimuthal derivatives. Additionally, a laboratory AF-MPD thruster for the power range of 10-20 kW has been built up at IRS. The goal of the experimental investigations is the characterization of the operation and performance parameters of the thruster.

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In the proposed gas-liquid equilibrium thruster, fuel is mainly stored in the liquid phase in the tank and is ejected in the gas phase, powered by the vapor pressure of the fuel. As compared to conventional thrusters, the thrust level of this thruster is low. However, the system configuration of this thruster is simple because components such as combustors or high-pressure reservoirs are not required. Further, this thruster is lighter than other thrusters. Fuels with low toxicity and that are easily available can be selected in this thruster from many kinds of fuel candidates. As a result, this thruster can be easily handled. This thruster can be used as an actuator for controlling the attitude and maneuvering the orbit of small satellites.

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This paper gives an overview of the currently planned on-orbit space verification experimental device complex composed of multiple inflatable demonstration units, proposed by the authors' group. The compact device named SIMPLE is designed to be suitable for one of the shared experimental installations that constitute a single experimental block attached to the Exposed Facility of Kibo Japanese Experimental Module (JEM) of ISS. The SIMPLE mission was accepted by JAXA as the candidate of the secondary application of the Exposed Facility of JEM at the end of last year.

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An extendible mast of a space-inflatable structure was used as a scientific probe onboard the sounding rocket S-520-23 launched in September 2007. The inflatable structure extended successfully and worked well as a scientific instrument. This was Japan's first space verification of a space-inflatable structure, and the world's first use of an inflatable structure as a practical antenna. The extendible mast as an inflatable structure is called “SPINAR” (SPace INflation Actuated Rod), and it consists of an extendible rod and inflatable extension mechanisms. The rod, which is an open section tubular member, can be stored around a spool and has the advantage of structural rigidity when extended. The principle of SPINAR is similar to that of STEM (Storable Tubular Extendible Member); however, relatively reduced weight and enlarged rigidity can be achieved in SPINAR if light and rigid composite materials replace the metallic STEM rod. In addition, an inflatable thin film tube is used as the extension actuator instead of an electrical motor for weight reduction, the extension mechanisms are simplified, and the storage and drive mechanism box are downsized. The inflatable tube does not have to be rigidized because of the virtual structural rigidization concept of the outer shell structure of the rod.

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Intelligent Space Systems Laboratory (ISSL) developed two CubeSats and develops the nano-scale remote-sensing satellite, “PRISM.” Two CubeSats are now in orbit and PRISM is now preparing for a launch. PRISM is so small that it has no rocket interface with it and another structure, “PHS,” which stands for PRISM Housyutu Souchi, plays a role of it. At the time of launches of two CubeSats ISSL developed an ejection system, T-POD and it succeeded separating four CubeSats. The authors consider that T-POD has high reliability enough and the authors develop PHS as an improved version of T-POD. In addition PHS has some original mechanism and structure, the reliability keeping mechanism, the flexible boom-defending mechanism and the putting in turnstile antenna structure.

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The Institute of Space and Astronautical Science JAXA is developing a landing radar comprising a radio altimeter and a velocity meter, which are two of the mandatory navigation sensors for a planetary lander. The landing radar employs a pulse-type radar using 4.3GHz C-band microwave radiation. It has a wide beam for measuring the altitude in vertical direction, as well as four narrow tilted beams for measuring the velocity in horizontal direction. A BBM of the landing radar has been evaluated on natural terrains by using a helicopter. This paper introduces the BBM hardware and discusses the dynamic performance in field experiments.

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A unique space robot is proposed to support astronauts' EVA work. The robot moves around the surface of a space facility, e.g. a space station. Usefulness of the proposed robot system will be tested in 2012 on the International Space Station Japanese Experiment Module.

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The H-II Transfer Vehicle (HTV), which is a Japanese unmanned cargo transfer spacecraft, will deliver supplies to the International Space Station (ISS). The first HTV will be launched in 2009 from the Tanegashima Space Center aboard an H-IIB launch vehicle with up to 6,000kg of supplies. HTV approaches to the ISS and the Space Station Remote Manipulator System (SSRMS), known as Canadarm2, will grapple the HTV and berth it to the ISS. After the supplies, the HTV will then be loaded with waste materials and then separated from the ISS by SSRMS. HTV conducts departure sequence from ISS after release from SSRMS and reentry to the atmosphere. In this paper, technology of HTV automated Guidance, Navigation and Control (GN&C) system is presented.

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Earth observation satellites are typically inserted into orbits which rendezvous with ideal target orbits and are precisely controlled to form and maintain formations with virtual spacecraft on the ideal orbits. As Earth observing instruments achieve higher spatial resolution, their subsatellite cross-track deviation requirements become more stringent, and a new application by SAR interferometry requires a further improvement in orbit control accuracy. The Advanced Land Observing Satellite (ALOS), which was launched on January 24, 2006 and has been operated successfully on orbit, required precision orbit control for high-resolution Earth observation and SAR interferometry under various practical constraints. This paper presents the ALOS orbit control strategy with a particular emphasis on requirements and practical constraints, and demonstrates the resulting on-orbit performance in which equator crossing points have been regulated within ±0.5 km from reference ground paths, and altitude variations over the same geo-locations have been kept within ±0.5 km.

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WINDS was launched in late February 2008 to demonstrate technologies enabling an ultra-high data rate communication network. WINDS is performing initial functional verifications of onboard components and systems. This paper describes the initial operation results on orbit and evaluates the performance based on the design and simulation data.

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ISACS-DOC (Intelligent Satellite Control Software-DOCtor), which is an automatic monitoring and diagnostic system for scientific satellites or spacecraft, aims to rapidly and accurately capture important changes and sign of anomaly during daily satellite operations. After three systems for deep space missions, the new generation of ISACS-DOC with a higher speed processing performance had been developed for the satellites in earth orbit, AKARI and HINODE. This paper reports on the newest ISACS-DOC about enhanced functions, operating status, and an approach to create standards to build and keep up the knowledge data base. Continuous enhancements through the actual operations are the advantage of ISACS-DOC.

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This paper provides an overview of a low-cost small university satellite. In June 2006, JAXA announced a program for the selection of H-IIA piggyback passengers to small-satellite projects performed by universities and regional communities in Japan. In this context, we started the satellite project named QSAT (Kyushu Satellite) in 2006. The primary objectives of the QSAT mission are 1) to investigate plasma physics in the Earth's aurora zone in order to better understand spacecraft charging, and 2) to conduct a comparison of the field-aligned current observed in orbit with ground-based observations. QSAT has two payload instruments, two plasma probes and a novel magnetometer. The laboratory of Spacecraft Environment Interaction Engineering of Kyushu Institute of Technology has the responsibility of the development of plasma probes, whereas, the Space Environment Research Center of Kyushu University has the responsibility of the development of the new magnetometer. The spacecraft bus is being developed at the Department of Aeronautics and Astronautics of Kyushu University with collaboration of Fukuoka Institute of Technology.

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This paper introduces an efficient data handling architecture for small satellites based on the design of the data handling system of QSAT. QSAT is the satellite which is being developed in Kyushu University together with other universities and local industries. The development concept of the data handling system of QSAT is straightforward, flexible, and reliable. Along with the concept, the hardware and software of the system is being developed. The architecture of the system is a distributed Linear type, using CAN communications as an internal data bus. For hardware, we developed a “Control Board” which is an electric circuit board including the CPU and several useful interfaces. At the same time, we develop the operating system specialized for the distributed system. The operating system is named Quartet2 and it is a simple real-time system that reacts to triggers from the hardware. With the combination of the developed hardware and software, an efficient and robust data handling architecture has been achieved.

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ISSL is now developing a new super small satellites for Earth remote sensing, “PRISM”. This satellite has a unique optics system with flexible extensible boom, aiming at 30m ground resolution. Super small remote sensing satellite can be used for the low-cost global Earth observation missions. To achieve such high ground resolution with flexible telescope, it has some compensation strategies against structural errors or dynamic movement. This satellite will be launched with GOSAT by H-IIA rocket in 2008, and we have finished FM development phase. This paper describes its key concepts and features of PRISM, as well as the problems we encountered and the methodologies for project management by university students.

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This paper describes the design process of the Fudai sun sensor (FSS) installed in a 50-kg-class micro-satellite, SOHLA-1. The FSS has been developed by the students of Osaka Prefecture University (OPU) with technical support from the Japan Aerospace Exploration Agency (JAXA) and Advanced Engineering Services (AES) Co. Ltd. In this project, the students experienced a series of processes required for developing satellite components, namely, design, production, test, launch, and operation.

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The paper proposes a de-orbiting system using inflatable balloon especially dedicated for nano-satellites. The system consists of a balloon of laminated aluminum film, gas supply system and electronics system which inflates the balloon when a certain signal comes from the satellite at the end of its life time. The balloon, once deployed, keeps its shape even after the gas expires. The package can be very small, low-cost and requires very little power for activation, which makes this system very attractive especially for university education satellites for which the satellite weight/size as well as cost are major concern. The BBM system has been developed and several ground experiments have been performed including deployment in vacuum environment and thermal cycle tests. We recognized that this system concept is viable and very promising as a de-orbiting system in the future when the satellite is ordered to have some method to avoid becoming space debris.

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The Laboratory for Space Systems at the Tokyo Institute of Technology has developed the nano-satellite Cute-1.7+APD. The satellite was launched by JAXA M-V-8 rocket on February 22, 2006 and operated for about a month. A successor to the Cute-1.7+APD was developed and is named Cute-1.7+APD II. This new satellite is based on its predecessor but has some modifications. In this paper an overview of the Cute-1.7 series and flight model development of Cute-1.7+APD II are introduced.

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MAXI (Monitor of All sky X-ray Image) is the first X-ray observation payload to be installed to EF (Exposed Facility) of Kibo (JEM: Japanese Experiment Module) on ISS (International Space Station). One of the important missions of MAXI is to quickly release novae or transient information of X-ray sources through its alert system to the worldwide astronomers. For this purpose, MAXI is equipped with a unique data transfer system both for the ground and on-board handling, which fully utilizes the communication system of ISS. The uniqueness of the data transfer system of MAXI comes from the fact that it is a payload of ISS, and is not seen in the ordinary payloads on free flyers (satellites). MAXI analyzes the observation data automatically in real time, and an alert for the novae or transient sources can be distributed widely through internet based on the analysis result. Various restrictions are imposed to keep tight security even on the ground system of ISS payloads. This paper describes the data transmission process in each stage, namely that in MAXI, the ISS communication links between the ISS and ground, and the process in the MAXI ground system.

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The U.S. human space transportation history from 1961 through 2007 is reviewed. Past and present U.S. human space programs and human space launch vehicles and spacecraft are briefly discussed. Category and chronological list of U.S. human space missions are presented. The emphasis of the study is on the investigation of mission failures and major anomalies encountered in the U.S. human space transportation history. Failures and major anomalies by part, root cause, element, function, domain, and component are analyzed. Failure outcome, failure mode, time of failure, and mission reliability relevant to flight safety analysis are examined. Findings and failure mitigation strategy are summarized.

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Non-U.S. human space transportation history from 1961 through 2007 is reviewed. Past and present non-U.S. human space programs and human space launch vehicles and spacecraft are briefly discussed. Category and chronological list of non-U.S. human space missions are presented. The emphasis of the study is on the investigation of mission failures and major anomalies encountered in non-U.S. human space transportation history. Failures and major anomalies by part, root cause, element, function, domain, and component are analyzed. Failure outcome, failure mode, time of failure, and mission reliability relevant to flight safety analysis are examined. Findings and failure mitigation strategy are summarized.

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The project of Winged Experimental Rocket described here is a proposal by the alliance of universities (University Consortium) expanding and integrating the research activities of reusable space transportation system performed by individual universities, and is the proposal that aims at flight proof of the results of advanced research conducted by the universities and JAXA using the university-centered experimental launch systems. This paper verifies the validity of the winged experimental rocket by surveying the technical issues that should be demonstrated and by estimating the airframe scale, weight and finally the total cost. The development schedule of this project was set to five years, where two airframes of different scales will be developed to minimize the risks. A 1.5-meter-long airframe will be first manufactured and conduct flight tests in the third year to verify the design issues. Then, a 2.5-meter-long airframe will be finally developed and conduct a complete flight demonstration of various research issues in the fifth year.

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JAXA is developing Mach 5 hypersonic turbojet engine technology that can be applied in a future hypersonic transport. Now, Jet Engine Technology Research Center of JAXA conducts the experimental study using a 1 / 10 scale-model engine. In parallel to engine development activities, a new supersonic flight-testing vehicle for the hypersonic turbojet engine is under development since 2004. In this paper, the system configuration of the flight-testing vehicle is outlined and development status is reported.

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HTV (H-II Transfer Vehicle) is the first Japanese un-manned service vehicle that will transport several pieces of equipments to ISS (International Space Station) and support human activities on orbit. HTV will be launched by the first H-IIB rocket in September 2009 and JAXA will have the capability to access LEO (Low Earth Orbit) bases with enough volume/weight as the human transport system. This paper is the preliminary study for developing a manned spacecraft from the HTV design and includes clarification of necessary development items. In addition, missing parts in the current HTV design are identified with some analysis, such as LES (Launch Escape System), which is mandatory for all human transport systems.

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The accuracy and the efficiency of the prototype of the Space Scale, which has been proposed as a practical and lightweight instrument for measuring the mass of astronauts under microgravity conditions in the International Space Station (ISS), have been evaluated by the parabolic flight tests. 2 series of the parabolic flight tests, in which the rigid metal structure and the human subject are used for the mass to be measured, have been conducted. The standard uncertainty of the mass measurement of the rigid object is estimated to be approximately 2.1 % for single measurement and 0.7 % for the average of 12 measurements. The present status and the future status of the Space Scale are discussed.

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Micro- and nanotechnology (MNT) is a rapidly advancing field of research with applications to benefit nearly all facets of society. At present it is unclear what role micro- and nanotechnologies will play in the space sector as they continue to develop. The authors have surveyed the existing space applications of MNT, and from these applications three concept designs have evolved that include a MNT demonstrator, MNT applications to space suit design, and a MNT-based atmospheric probe for exploration. The three concept designs focus on specific systems for a spacecraft. The hierarchical approach of breaking a spacecraft down into systems and subsystems solidifies a methodology for investigating microsystems and nanotechnology as a means to reduce mass or increase capability within the larger system. MNT may reduce the cost of accessing and working in space, but may also lead to value added functions of existing space technologies irrespective of size and cost. This paper provides an appreciation of the wide number of potential and future applications these technologies can bring to the space community.

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Japan Aerospace Exploration Agency (JAXA) is now preparing the first utilization activities in “KIBO”. JAXA already completed the hardware productions of the first experiment facilities and succeeded their launch to the International Space Station in March 2008. JAXA plans the fluid physics and material science experiments, several lifescience experiments, measurement of the radiation environment in “KIBO”, demonstration of high definition television system, some educational and commercial programs in 2008. Most of the preparation works of making the operational products for the execution of each activity have already done. The setup of the ground operation system in JAXA Tsukuba Space Center for KIBO operation was completed and the end to end communication data flow was validated. The establishment of a JAXA payload flight controller team are also undergoing right now and the general training of the team has completed.

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An experimental apparatus for growing colloidal crystal under microgravity conditions in the International Space Station (ISS) was developed. The apparatus was designed so that all experimental steps proceeded automatically with the use of a sequential controller unit. The crystal growth cell (CGC) in which the ionic condition of colloidal dispersion medium was gradually changed with time by diffusing ions through barrier gel was designed and fabricated with polymethylmethacrylate (PMMA). The grown colloidal crystal was immobilized by photoinitiated polymerization to form polymer gel using a commercially available near-ultraviolet (UV) light-emitting diode (LED). The apparatus was proven to work well for a one month mission.

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The paramedic in the moving ambulance sends via the communications satellite the moving picture data to the doctor in the hospital However, when an ambulance runs inside a city, a radio wave to the communication satellite is blocked and as a result the moving picture data sometimes freeze. Maximum value of the satellite visibility by the space diversity which uses two geostationary satellites is acquired in each city of Japan. From these simulation results, it was found that there was a limit in the improvement of the satellite visibility by the space. The limit of this improvement depends on the city. .Moreover the angle of elevation of the quasi zenith satellite which the satellite visibility exceeds the limit value of two geostationary satellites was acquired ,and these angles of elevation were compared between each city of Japan. It became clear that more than 69 degrees of an elevation angle of the quasi zenith satellite is necessary to exceed a maximum satellite visibility of two geostationary satellites.

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SELENE (Kaguya), which was successfully launched on Sep. 14, 2007, consists of the main orbiter, and two small free-flying sub-satellites, called Rstar (OKINA) and Vstar (OUNA). We use multi-frequency VLBI to measure the angular distance between the two sub-satellite radio sources Okina and Ouna in order to improve the accuracy of the low degree gravitational harmonics and the gravity field near the limb. The observations are made at three frequencies in S-band, (2212, 2218 and 2287 MHz), and one in X-band, (8456MHz) with carrier waves. The Japanese domestic VLBI network, VERA, will conduct VLBI observations for the whole mission period of one year. In addition, we will conduct two periods of international observations, each one month in duration, which will also include the international stations, Shanghai, Urumqi, Hobart, and Wettzell. We have succeeded in making VLBI observations of Okina/Ouna with VERA and the international network, and have also succeeded in correlating of signals from Okina/Ouna. We obtained phase delays with an accuracy of several pico-seconds in S-band.

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MAP-PACE (MAgnetic field and Plasma experiment - Plasma energy Angle and Composition Experiment) is one of the scientific instruments onboard the KAGUYA (SELENE) satellite. PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measure the distribution function of low energy electrons below 15keV, while IMA and IEA measure the distribution function of mass identified low energy ions below 28keV/q. Since KAGUYA is a three-axis stabilized spacecraft, a pair of electron sensors (ESA-S1 and S2) and a pair of ion sensors (IMA and IEA) are necessary for obtaining three-dimensional distribution function of electrons and ions. Low energy ion measurements on the lunar orbit have been realized more than 30 years after the Apollo period. In addition, nobody has ever measured the mass identified three-dimensional distribution function of low energy ions at 100km altitude. PACE discovered surprisingly active low energy ion environment around the Moon. Instead of being absorbed by the lunar surface, quite a large amount of solar wind ions are reflected back from the Moon. The reflected solar wind ions are accelerated above solar wind energy picked up by the electric field in the solar wind.

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Manned lunar explorations are planned in several countries for future goals of their space exploration. Many scientists and engineers are considering that the lunar human outpost will be established no later than early 2020s. The manned lunar mission should be considered as the real problem. To construct rigid lunar bases, the investigation of shallow structure of the moon is required. Here the authors present current technology and understandings of investigation method of lunar shallow structure, and proposes plausible exploration scenario for forthcoming unmanned landing explorations.

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The Moon-orbiting KAGUYA (SELENE: Selenological and Engineering Explorer) was successfully launched on Sep. 14, 2007 from JAXA Tanegashima Space Center. It was injected into the lunar orbit on Oct.4, 2007 on schedule. It started science mission in mid-December after checkout of each mission instruments. The scientific objectives are; 1) study of the origin and evolution of the Moon, 2) in-situ measurement of the lunar environment, and 3) observation of the solar-terrestrial plasma environment. Totally 14 mission instruments on the main orbiter and two subsatellites (OKINA and OUNA) have been operated. This paper presents the major results of scientific obsevation in the initial mission operation phase.

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The Laser Altimeter (LALT) on board the main orbiter of KAGUYA (SELENE) started nominal observation on December 30, 2007 for mapping the lunar topography. As of March 31, 2008, LALT has obtained about 6.7 million topographic data and the return rate is 97%. Several qualifications of the data to produce reliable topography are now in progress. The present status and preliminary results are reported in this article.

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The Upper Atmosphere and Plasma Imager (UPI) was launched in 2007, and went to the moon. From the lunar orbit, two telescopes direct toward the Earth. The moon has no atmosphere, which leads no active emission near the spacecraft, thus we have a high quality image of the near-Earth environment. Moreover the moon orbits the Earth once a month and the Earth is observed from many different directions. This is called a "science from the Moon". The two telescopes are mounted on 2-axis gimbal system, Telescope of Extreme ultraviolet (TEX) and Telescope of Visible light (TVIS). TEX detects the O II (83.4nm) and He II (30.4nm) emissions scattered by ionized oxygen and helium, respectively. The targets of EUV imaging are the polar ionosphere, the polar wind, and the plasmasphere and the inner magnetosphere. The maximum spatial and time resolutions are 0.09 Re and 1 minute, respectively.

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SELENE Main Orbiter (KAGUYA) has separated two small sub-satellite (1) the Relay Satellite “Rstar (OKINA)”, and (2) the VLBI Radio Satellite “Vstar (OUNA)”. These sub-satellites started to perform 4-way Doppler measurements using Relay Satellite Transponder (RSAT) and multi frequency differential VLBI using VLBI Radio Sources (VRAD) for selenodesy. Initial check out was executed and properties of satellite bus equipments, onboard mission instruments, and observation systems including ground stations were evaluated. Electric power and thermal control subsystems have shown that they conduct as designed and inspected in the ground tests. The release mechanisms have given the spin which can maintain the stability of the satellite attitudes. Communication functions of mission instruments conform to the link budgets. These results suggest that Rstar and Vstar have enough performances to produce efficient selenodetic data by RSAT/VRAD observations.

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The status of the X-ray spectrometer XRS onboard SELENE (Kaguya) is reported. The XRS is to map major elemental composition of lunar surface but is subject to instrumental trouble and unexpectedly faint solar activity. However it observed X-rays from the onboard standard sample excited by solar X-rays and non-solar X-ray events, maybe by particle events.

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We constructed search system based on published lunar nomenclature data. This system uses the concept of Query-By-Object approach which all search results can be treated as the objects. Using this method, users can combine any search result to obtain the result they want. Therefore, this result is suitable for complex search demanded by researchers. This search system can help mainly researchers to find lunar surface objects by name more smoothly than check lists on the book or the web page. Additionally, the system design is so flexible that the system can link to other system such as lunar GIS and other search scheme. The system will form one piece of the all-round lunar and planetary data processing platform.

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Tanpopo, dandelion, is the name of a grass whose seeds with floss are spread by the wind. We propose the analyses of interplanetary migration of microbes, organic compounds and meteoroids on Japan Experimental Module (JEM) of the International Space Station (ISS). In this paper we will introduce the target and basic design of the project.
In “Tanpopo” project, ultra low-density aerogel will be used to capture micrometeoroid and debris. Particles captured by aerogel will be used for several analyses after the initial inspection of the gel and tracks. Careful analysis of the tracks in the aerogel will provide the size and velocity dependence of debris flux. The particles will be analyzed for mineralogical, organic and microbiological characteristics. Aerogels are ready for production in Japan. Aerogels and trays are space proven. All the analytical techniques are ready.

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The BepiColombo is an international Mercury exploring mission which will be launched in 2014 and reach the planet in 2020. In this paper, we show the development status of the extreme ultraviolet (50-155 nm) detector for the mission. We have optimized the geometry of the micro channel plate that can achieve highest quantum detection efficiency. Furthermore, we have evaluated the quantum detection efficiencies of cesium iodide-coated micro channel plate which have been exposed to the air or dry nitrogen, in order to determine the treatment procedure to prevent performance degradation until the launch.

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On September 14, 2007, Moon explorer SELENE (Kaguya) was launched to the Moon carrying a 10-m spatial resolution stereo-camera, the Terrain Camera (TC). Particular mission objectives of the TC include Polar regions and Mare regions such as Oceanus Procellarum, South-Pole to Aitken basin, and Mare Orientale, that have not been observed with TC's high-resolution stereoscopy. The first TC data of the Moon were obtained on Nov. 3, 2007. We confirmed 1) that the TC had not generated any defective pixels and would achieve high signal-to-noise ratio (S/N) performance and 2) that the TC could provide high-quality data in the Polar regions and a 180 km region extending from 60N to 66N along 240E. We could acquire scientific information from ortho images and digital terrain models (DTMs) produced from these TC first data. On Nov. 24, 2007, we acquired several sequential strip data, from which a seamless mosaicked TC ortho image and DTMs were successfully produced. These seamless mosaicked data will be very useful for investigating large mare regions. After completion of the nominal checkout phase on Dec. 21, 2007, the TC began the nominal mission operation phase with other mission instruments. Thus, we could confirm that TC will provide fundamental assets for lunar science from the initial checkout phase data.

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The Japanese lunar mission SELENE (Kaguya) was successfully launched by the H2A No.13 rocket on September 14, 2007. After being inserted into a nominal orbit at an altitude of 100 km for remote sensing on October 19, 2007, a sounder antenna, magnetometer boom, and plasmasphere cameras were deployed before the testing of scientific instruments. Acquisition of scienctific data was carried out for ten months after the nominal mission period that began from the middle of December, 2007. Scientific objectives and perspectives along with the status of the initial operations of Kaguya are described in this paper.

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Successful robotic planetary exploration missions are not without technical and scientific challenges. Appropriate control and mobility of the robot is critical for successful exploration in unstructured environments. We address these problems through an overview of an under development telerobotic platform for exploration missions to the lunar craters. The platform is based on a novel transforming hybrid walking/roving Lunar Exploration Omnidirectional Netbot (LEON). We describe a versatile dynamic engine based simulator/teleoperation platform called ERode (Eric Rohmer Open Dynamic Engine), which allows developing, simulating and teleoperation of LEON. We also introduce the novel hybrid wheel/limb design of LEON, whereby two of its six limbs fold into themselves transforming into wheels. This possibility of transformation results in increased mobility in the environment, by adapting to different soil conditions. Furthermore, this system has a limited bulkiness compared to hybrid systems owning both wheels and legs, and it has an increased wheel diameter compared to hybrid systems having wheels at the tip of their legs. Preliminary experimental or simulated results are also presented, showing the performance of the hybrid system dealing with different types of terrain.

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The H-II Transfer Vehicle (HTV) is an unmanned transfer vehicle that will rendezvous with manned facilities and deliver up to six tons of cargo. HTV is a key space transportation system technology in Japan together with the H-IIA/H-IIB launch vehicle and is designed to fully satisfy the manned safety requirements of the International Space Station (ISS) program. Therefore, the technology and its system acquired through HTV development and operation will be widely utilized in future manned transportation and lunar and planetary exploration missions.

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