“SAKIGAKE”, the first interplanetary spacecraft of Japan was successfully launched from Kagoshima Space Center on January 8, 1985. The name SAKIGAKE means the pioneer and its main mission is the verification of the launch capability of newly developed Mu-3SII launch vehicle and the technology applied to the Halley”s comet explorer “SUISEI”, as well as the communication link ability between the spacecraft and Usuda Deep Space Center (UDSC). SUISEI means a comet and its launch on August 19, 1985, was also perfect, and two spacecraft are flying on their due courses to Halley’s comet. The design of both spacecraft is almost same except for the scientific instruments. In this paper the spacecraft system design, the characteristics of subsystems and the present status of these two spacecraft in flight are described.

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A strategy of materials processing in space is described especially from the view point of industrial utilization.

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In this paper we deal with the modeling and control problems of a free-flying teleoperator with manipulators. As the motion of the manipulators is interacted with the motion of the satellite body, the dynamics and control problems become more complicated than ground-based manipulators. We first expand the inverse dynamics scheme using Newton-Euler formulation, which is successfully applied to ground-based manipulators, to the satellite-mounted manipulators, and derive the equations of motion of the teleoperator system by the use of the inverse dynamics scheme. The procedure to obtain the equations is rather simple in spite of the topological tree configuration of the teleoperator. Then, we consider the control method of the teleoperator system, the satellite attitude control and the manipulator joint control. The method we propose here is the feedback control in which the satellite linear acceleration is estimated first and then the satellite and manipulator control torques are calculated. This control method is verified by a simulation study.

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A solar-pumped laser for space use is reviewed in relation to the laser medium employed. The characteristics of a solar-pumped solid-state, gas and liquid laser are discussed respectively. Our experimental results on the solar-pumped Nd:YAG laser using a large solar concentrator are reported also.

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A multi-model Maxwellian distribution including effects of turbulent fluctuations is shown to be an equilibrium solution of the Boltzmann equation without molecular chaos. The classical Maxwellian distribution is obtained from this solution in the limit of vanishing turbulent intensity. This finding tempts us to make a conjecture on the existence of nonquiescent turbulent equilibrium prevailing eventually. The turbulence level, however, is expected to be very low and hardly detectable except under microgravity circumstance where disturbances due to buoancy effects are suppressed below a certain level.

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