The Moon is the nearest celestial body to our Earth. Humans first visited the Moon in 1969. However, only short term stays have been possible. In order for long-term missions to be possible, large pressurized constructions are needed. The 15-20 m
Altair habitat planned in the Constellation Program and the 6.65 m
pressurized crew compartment volume realized in the Apollo program are insufficient. Hundreds of cubic meters per crew member are required for living area, working area, greenhouse with sufficient plants and animals for food, air and water recovery and storage. Projects discussing such large metal constructions delivered from Earth were proposed since the first flight on Moon. However, this method is not realistic: such large construction cannot be launched from Earth (too big mass and size), large construction cannot be landed on the Moon (too big inertia), building of large constructions on the Moon requires a long presence of workers (workers need pressurized cabins, life support system, water, and food that needs large construction to deliver and to keep it), delivering of separate blocks to one place with landing rockets (accuracy of landing of a few meters is too complicate, or it needs Moon’s tracks to collect all landed blocks). Therefore, a moon base should be constructed on the Moon itself.