Plans for submillimetre and infrared satellites in Japan

I describe plans for submillimetre and infrared satellites which are now under discussion among Japanese infrared and millimetre astronomers. We propose a submillimetre and/or infrared mission to be launched around 2000 with a main reflector 1–2 m in diameter and cooled down to 50–150 K. This mission, although a small one, will be able to contribute significantly to the advance in submillimetre and infrared astronomy if its role is specified for suitable purposes like surveys.     

Space radiation enhancement linked to geomagnetic disturbances

Space radiation dosimetry measurements have been made on board the Space Shuttle. A newly developed active detector called "Real-time Radiation Monitoring Device (RRMD)" was used (Doke et al., 1995; Hayashi et al., 1995). The RRMD results indicate that low Linear Energy Transfer (LET) particles steadily penetrate around the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent and some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions (Doke et al., 1996). We also have been analyzing the space weather during the experiment, and found that the anomalous high-energy particle enhancement was linked to geomagnetic disturbance due to the high speed solar wind from a coronal hole. Additional analysis and other experiments are necessary for clarification of these phenomena. If a penetration of high-energy particles into the low altitude occurs by common geomagnetic disturbances, the prediction of geomagnetic activity becomes more important in the next Space Station's era.     

ETS-II Experiments Part I: Japan's First Geostationary Satellite

Engineering Test Satellite Type II (ETS-11) "Kiku-2" was launched on February 23, 1977, and positioned in geostationary orbit at 130°E on March 5. Propagation experiments have been carried out by using 3 coherent beacons at 1.7, 11.5, and 34.5 GHz on a 24 h/day basis from late in April. The project and related plans are outlined. The 4 papers which follow in this Transactions introduce the experimental system and preliminary results using data from May to November 1977.     

Vapor compression distiller and membrane technology for water revitalization.

Water revitalization for a space station can consist of membrane filtration processes and a distillation process. Water recycling equipment using membrane filtration processes was manufactured for ground testing. It was assembled using commercially available components. Two systems for the distillation are studied; one is an absorption type thermopervaporation cell and the other is a vapor compression distiller. Absorption type thermopervaporation able to easily produce condensed water under zero gravity was investigated experimentally and through simulated calculation. The vapor compression distiller was studied experimentally and it offers significant energy savings for evaporation of water.