VARIOUS PROBLEMS IN LUNAR HABITAT CONSTRUCTION SCENARIOS

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 He-3, 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.