We saw quite a few milestones notched in the final frontier this year. But there were a number of failures as well, some of them quite dramatic.
Beneath the Moon’s cratered surface lie networks of lava tubes and deep pits, natural caves that could shelter future lunar bases from cosmic radiation and wild temperature swings. These underground structures represent some of the most scientifically valuable areas in the Solar System, but they come with the very real challenge of simply getting there!

