Do we know how many Starship launches SpaceX will need to get NASA astronauts to the moon? No. Will its refuelling plan be simple? Also no.
NASA's Artemis IV mission plans to use SpaceX's Starship as the lunar lander, but the number of refueling flights required remains uncertain. According to Space.com, a Government Accountability Office audit estimated up to 16 flights, while a safety panel member suggested as many as 22, though SpaceX's CEO said it would be closer to six or eight.
The refueling process involves multiple stages: a depot ship is launched to low Earth orbit and filled by several tanker flights; the Starship lander then docks for an initial refuel, moves to a higher "final tanking orbit," and meets the depot again after it is refilled by another set of tankers. This staggered approach is intended to give flexibility to the SLS launch schedule and reduce overall propellant needs by sending Orion directly to low lunar orbit.
The plan is not final; if SpaceX cannot demonstrate orbital refueling or an uncrewed lunar landing by the end of next year, NASA may choose Blue Origin's Blue Moon lander instead. Further details are expected as the launch date approaches.
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