A Review of Technical Requirements for Lunar Structures: Present Status

Abstract

The moon, as an important and close destination for research and planetary exploration, has recently regained the interest of many of the world's national and international space agencies (such as NASA, ESA, and others). Lunar missions are the first steps in expanding manned and unmanned exploration inside our solar system. The moon represents various options. It can be used as a laboratory in lower gravity (1/6 of the earth's gravity field), it is the closest and most accessible planetary object from the earth, and it possesses many resources that humans could potentially exploit. Missions to the moon of different complexity and different objectives are planned in the near future by various space agencies. This demonstrates a strong return of interests since the Apollo program era and invites a review of the current understanding and knowledge of the lunar environment for future lunar construction. This paper has two objectives: first, to review the current status of the knowledge of lunar environmental requirements for future lunar structures, and second, to present a new classification of lunar structures based on the current knowledge of the subject. With this information, a Lunar Construction Code is proposed to be evolved, which would guide all future lunar construction. The new classification divides the evolution of lunar structures into three phases. The first phase is building small shelters for equipment only. In the second phase, small temporary habitats will be built, and finally in phase three of development, habitable lunar bases will be built together with independently constructed observatories and/or laboratories, or in some cases with production plants. Initially, the main environmental concerns will be lunar dust and meteoroids. Other factors should be considered for lunar structural development involving extended periods of human presence. The list of factors includes effects due to the lunar vacuum environment, lunar gravity, the cosmic and other radiation, a rapid change of temperature, and the length of the lunar day. This paper presents a classification of various technical requirements based on the current knowledge of these factors, and their importance in each of the phases of construction. It gives recommendations for future research in relation to the development of conceptual plans for lunar structures, and for the evolution of a lunar construction code to direct these structural designs. Some examples are presented along with the current status of the bibliography of the subject. The specific sources of lunar information are also presented.