Telecommunications systems are indispensable to control spacecraft and gather telemetry data from space. After the launch of each spacecraft, the telecommunications systems worked well and supported the observation around the encounters with Halley's comet. The system performances have been confirmed to be coincident with the design through operations. This chapter describes the design principle and constitution of the telecommunications systems, and the operational results together with system evaluations.
Microwave emission was found when materials were destroyed by a static pressure. This paper describes the experimental setup to observe the phenomena, the obtained terms and results and the method to convert to power. According to the obtained experimental results, the cause of microwave emission is inferred to be the dissociation of atoms or molecules, but is not yet completely confirmed. Currently, the phenomenon is expected to be applied to geophysical explorations in the earthquake detection.