Exploring light and colour in space habitats: A scoping review of habitability studies

The psychological and physiological health of astronauts in microgravity is influenced by multiple factors, amongst which light and colour design has a crucial role in alleviating stress and optimizing overall habitability. However, current lighting and colour optimization strategies in space stations lack spatial differentiation, rely on subjective and fragmented evaluation methods, and are limited by unclear regulatory mechanisms. These issues hinder progress in optimizing space environments. This study reviewed the psychological and physiological effects of long-term spaceflight and the regulatory impact of light and colour on the human body. Based on the current state of space station designs and the hierarchy of human needs, functional requirements and zoning were clarified. A comprehensive examination of light and colour schemes has highlighted how optimized design can improve habitability in microgravity. Furthermore, the indicators and corresponding methodologies for evaluating environmental influences on humans was summarized, and a multi-level, interdisciplinary framework for optimizing future space station lighting and colour design has been proposed. Future research should systematically explore the effects of different schemes using, subjective, physiological, task performance and quantitative analyses, based on psychology, medicine and related fields. Human factors and environmental-design-integrated feedback were assessed to scientifically guide improvement in space station light and colour habitability.