Life Support Systems Trade Study for Lunar Habitation with Greenhouse Food Production

The Japan Aerospace Exploration Agency (JAXA) established the Space Exploration Innovation Hub Center called TansaX (Technology Advancing Node for SpAce eXploration) in 2015. TansaX specializes in technology research applicable to daily life as well as future lunar and Mars exploration. The author has been a member of the lunar farm group and its system design sub-group at the center since 2017. The author conducted a trade study to support lunar farm design by using a bioregenerative Life Support System (LSS) analysis tool and a life support system size analysis tool. This paper describes the analysis tools and the computational design procedures; in addition, an LSS design with the lunar farm for six crewmembers was analyzed. The initial mass, logistics mass, and Equivalent System Mass (ESM) of the LSS and its subsystems were compared. Increasing the utilization efficiency of mass and volume by increasing the vertical stacked layers of crops is recommended if the amount of crop cultivation is large, because the LSS initial mass can be decreased by this approach. The total mass value of the closed LSS with a downsized biomass production system was less than those of the open LSS and International Space Station (ISS)’s LSS after 600 days and 1,050 days of operation, respectively. However, the ESM value of the closed LSS with a downsized biomass production system was more than the ESM values of the open LSS and ISS’ LSS systems until 2,000 days and 3,950 days, respectively.