Fang Lin had naturally seen the construction proposal that Zhang Zhiguang spoke of, but he had felt it was too fantastical at the time.
According to existing data, during the period of ancient volcanic activity, the Moon had many flows of magma on its shallow surface, which, upon cooling, formed long underground caves that naturally serve as both a stroke of good fortune and a barrier against cosmic radiation.
Fang Lin really wanted to utilize these caves as a protective shell for the space base, so he proposed a method:
He suggested dropping metal rods from lunar orbit to strike the surface of the caves, creating a large hole suitable for the descent of a lander, and then directly landing the spacecraft inside. Using the relatively pure lunar dust as a material for 3D printing on-site, they could build the outer surface of the living quarters. With the shelter of the caves, this could enhance the base's resistance to various threats.
