Lava tubes formed billions of years ago when molten lava carved tunnels beneath the surface. Some stretch for kilometers and remain structurally stable. These tubes could protect from radiation, micrometeorites, and temperature extremes. Lunar recon missions use radar to detect them. They’re natural habitats for future bases. Studying their stability is crucial before habitation. Tunnels preserve geologic history inside.
It matters for colonization and habitat planning. Underground shelters reduce risk from harsh surface conditions.
It also provides a testbed for extraterrestrial construction techniques. Lava tubes could be adapted on Mars too.
Some tubes could be over 500 meters wide.
NASA [nasa.gov]