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Productivities of 29 crops in the Closed Ecology Experiment Facilities (CEEF) were measured. Rice and soybean showed higher productivities than these given by the Advanced Life Support System Modeling and Analysis Project Baseline Values and Assumption Document (BVAD), but productivities of some other crops, such as potato and sweet potato, were lower. The cultivation data were utilized to develop a 1-week cycle menu for Closed Habitation Experiment. The menu met most of the nutritional requirements. Necessary cultivation area per crew was estimated to be 255 m2. Results from this study can be used to help design the future Advanced Life Support System (ALSS) including the CEEF.

Through the tentative lunar base construction study aiming to explore the system design method regarding closed loop life support system, the feasible system configuration including many subsystems is defined. Based upon this configuration and the estimated metabolic data of human and plants, the required material flow quantities between each subsystem in order to keep the appropriate condition for human and plants have been estimated. For promoting such fundamental researches on these subsystems and for planning the installation of test beds to check the closed loop life support function, new institute, Institute for Environmental Sciences, has been established in the end of last year.

For the Closed Ecological Life Support System (CELSS) of a manned lunar base which is planned to be built on the moon early in the 21st century, several proposed programs exist to grow vegetables inside a farming module. 1)2)3)4)5) At the 40th IAF (Malaga, 1989) the author et al presented a proposal for supplying food and nutrients to a crew of eight members, a basic concept which is based on growing four kinds of vegetables. 6) This paper describes measures for biohazard protection in farming modules. In this study, biohazard protection means prevention of the dispersion of plant diseases to other plant species or other portions of farming beds.

Many papers describing the lunar base construction have been published previously. Lunar base has been considered to be a useful facility to conduct future scientific programs and to get new nuclear energy resource, namely 3He, for defending the environmental collapse on Earth and also to develop lunar resources such as oxygen and nitrogen for extending human activities in space more economically. The scale of the lunar base and the construction methods adopted are determined by the scenario of a lunar utilization program but constrained by the availability of the established space transportation technologies. As indicated in the scenarios described in papers regarding lunar base construction, the first steps of lunar missions are the investigation of lunar itself for conducting scientific research and for surveying the lunar base construction sites, the second steps are the outpost construction for conducting man-tended missions, for more precise scientific research and studying the lunar base construction methods, and third steps are the construction of a permanent base and the expansion of this lunar base for exploiting lunar resources. The missions within the first and second steps are all possible using the ferry (OTV) similar to the service and command modules of Apollo Spacecraft because all necessary weights to be landed on the lunar surface for these missions seem to be under the equivalent weight of the Apollo Lunar Lander. On the other hand, the permanent facilities constructed on the lunar surface in the third step requires larger quantities of construction materials to be transported from Earth, and a new ferry (advanced OTV) having higher transportation ability, at least above 6 times, compared with Apollo Service and Command Modules, are to be developed. The largest problems in the permament lunar base construction are related to the food production facilities, 30–40 m2 plant cultivation area per person are required for providing the nutrition requirement and the necessary electric power per person for producing high energy foods, such as wheat, rice and potato, are now estimated ranging from 30 to 40 kW. The extension program of crew numbers under the limitation of usable transportation capability anticipated at present and the construction scenarios, including the numbers of facilities to be constructed every year, are to be determined based upon the requirements of plant cultivation area and of electric power for producing necessary and sufficient foods in order to accelerate the feasibility studies of each subsystem to be installed in the permanent lunar base in future.

Much of papers describing the Lunar Base Construction have been already published. Lunar Base has been considered to be one of the very useful facilities to conduct the excellent scientific program in near future and also to develop the lunar resources such as 3 He and oxygen in order to expand the human activities in space. The scale of lunar base and the construction methods to be adopted should be determined based upon the utilization program to be conducted after the initiation of outpost habitation. In order to construct lunar base, it needs to transport lunar base elements such as habitat modules, experiment modules and so on having 20–30 tons weight and to install, connect and activate on lunar surface. The development of transportation system such as OTV enabling to transport over 30 ton payload weight from earth to moon seems to be very difficult in near future, and it seems reasonable to transport three elements per year as described in many papers already published. /1/. Therefore, the initial habitat outpost would not have enough volume to produce foods and has to have ECLS system similar to that of space station already going to be developed. After 2–3 years from the initiation of habitation, the addition of food production facilities could be started to expand the habitability of lunar base and finally the complete closed loop life support system could be installed after spending 6–7 years. This paper describes ECLS technologies to be used in the initial habitat outpost and design philosophy of the closed loop technologies to be utilized in the final stage.

Recognizing the importance and fertility of the extra vehicular activity technologies in future space development and utilization, some related research activities have been conducted in Japan, though it has not committed itself to developing its own manned space flight capability. The purpose of this paper is to introduce and evaluate these EVA-related activities and to indicate the next step for Japan to get into the era of manned space activities including EVA in reality.

In the next century, mankind will expand its activity to the moon and Mars. At that time, humans will be exposed to a low and micro-gravity environment in long term which causes physiological and psychological problems. The authors propose an artificial gravity space station for a research laboratory on human physiology and psychology at various gravity levels. The baseline specifications and the configuration of the space station are shown. Reviewing the history of manned space flight, the necessity of the research on an artificial gravity space station is discussed, including themes of research to be conducted on the station and the application of its results. Technical issues for realization of the space station such as environmental factors, system function and assembly scenario are also discussed.

The Closed Ecology Experiment Facilities, CEEF, one of the Environmental Time Machine, is now planning to be constructed in the northern part of Japan with an eye to study the effect of atomic power industries on the local environment. This CEEF can be used not only for investigating the environmental problems related with atomic power industries but also for various environmental problems such as the habitation in lunar & Mars bases and the development of mathematical model to predict the change and change rate of earth parameters. Researches on earth environment and earth system science are discussed with use of CEEF. Preliminary experiments using a small growth chamber showed different results from those estimated by Simple Biosphere Model being used in the climate estimation.

Many agricultural and other experiments relating to the development of a Controlled Ecological Life Support System (CELSS) were proposed by scientists throughout Japan in the fall of 1982. To develop concrete experimental concepts from these proposals, the engineering feasibility of each proposal was investigated by a CELLS experiment concept study group under the support of the National Aerospace Laboratory. The conclusions of the group were described in two documents, /1/, /2/. Originally, the study group did not clearly define necessary missions leading to the goal of an operational CELSS for spaceflight. Therefore, the CELSS experiment concept study group met again to clarify the goals of CELSS and to determine three phases to achieve the goals. The resulting phases, or missions, and preliminary proposals and studies needed to develop a CELLS are described herein.

As weIl known, World-wide trend regarding space transportation system has begun to change from the utilization of U.S. Shuttle to the development of their own transportaion system such as Hotol, Hermes and Sanger project in order to keep their freedom of space activities under their own rights since the space shuttle tragedy occured. In order to keep the freedom of own space activities, not only space transportation system, but also various orbital facilities such as their own platform, their own space station and so on, so called space infrastructure, should be constructed and operated. Author forecasts Japanese manned space activities in future and proposes to construct Japanese manned facilities with artificial gravity for easing the crew of pain related with space symptoms and for expanding research activities from earth bound flight to planetary flight and describes various technological problems regarding EVA suits, the life support system in future activities and also the psychological problems of long duration stay in space.

In order to prolong the duration of manned missions around the Earth and to expand the human existing region from the Earth to other planets such as a Lunar Base or a manned Mars flight mission, the controlled ecological life support system (CELSS) becomes an essential factor of the future technology to be developed through utilization of space station. The preliminary system engineering and integration efforts regarding CELSS have been carried out by the Japanese CELSS concept study group for clarifying the feasibility of hardware development for Space station experiments and for getting the time phased mission sets after FY 1992. The results of these studies are briefly summarized and the design and utilization methods of a Gas Recycle System for CELSS experiments are discussed.