Life Support for a Low-Cost Lunar Settlement: No Showstoppers

In 2014, space experts were challenged to develop strategies that would enable 10 people to live for 1 year on the Moon by 2022 for a total development cost of $5B. This was to be done in a manner that would minimize resupply of consumables from Earth and lead to a permanent lunar settlement of 100 people within 10 years. To sustain small groups on the Moon within this budget, recycling life-support consumables, rather than continuously supplying them from Earth, is required. The International Space Station (ISS) provides existence proof that these technologies are currently available. On the ISS, physicochemical regeneration of air and water reduces resupply of these consumables by more than 80%, increases the resilience of missions, and enhances productivity by enabling science, technology, and commercial payloads to replace life-support consumables. A permanent settlement must also employ bioregenerative strategies where, in addition to providing food, plants also remove carbon dioxide, produce oxygen, and generate potable water from gray water. Food production is only practical if abundant sunlight (or power) provides the light necessary for photosynthesis. Thus, quasicontinuous sunlight, obtainable only near the poles, is the most important resource for meeting time and budget constraints, although regolith constituents and lunar polar hydrogen (presumably ice) deposits are also valuable assets. Although improvements are always beneficial, the technologies needed for life support for the first phase of Lunar Settlement are available now.