Lunar bases could support a staged Mars supply chain

The proposed Mars supply chain begins with a base on Earth's Moon, followed by a station on a suitable Martian moon. Experience gained close to Earth would inform construction farther away, while the second station could accumulate supplies before a settlement on Mars is attempted. Separate vehicles would handle surface-to-moon transport and the journey between the two moons. A craft that remains in space avoids atmospheric entry requirements, although radiation shielding remains necessary. Low-thrust propulsion could then serve a different role from the engines needed to reach orbit. The station near Mars would give an expedition somewhere to withdraw during an emergency, while its own risks would require compartmentation and lessons learned from the nearer base.