How many Starship launches will SpaceX need to refuel the lunar lander for NASA’s Artemis IV mission? Current estimates differ, and NASA’s outline shows a multi-stage process involving fuel transfers in both low Earth orbit and a higher orbit before the crewed mission begins.
Past estimates have ranged from as many as 16 refueling launches in a 2021 Government Accountability Office audit to 22, a figure recently cited by a member of the Aerospace Safety Advisory Panel. SpaceX CEO Elon Musk disputed the latter estimate, saying the number would be closer to six or eight. NASA’s mission graphic does not specify how many tanker flights will be required.
Under the outline, SpaceX would first launch a depot to low Earth orbit (LEO), then send tanker Starships to fill it. The lunar lander would dock with the depot for an initial refueling before moving to what NASA calls the “final tanking orbit.” More tanker flights would replenish the depot, which would then meet the lander for a further fuel transfer.
Once refueled, Starship would travel to high Earth orbit and dock with NASA’s Orion spacecraft. The Space Launch System rocket is expected to send Orion and the four Artemis IV astronauts into that orbit. The spacecraft would then travel toward the Moon, where two astronauts would transfer to Starship for the descent to the lunar surface. They would later return to lunar orbit and rejoin Orion for the journey home.
NASA says the staggered sequence is intended to give the agency more flexibility in choosing when to launch the crew. The plan would also reduce the amount of fuel needed, in part because Starship would take Orion to low lunar orbit rather than the higher orbit considered in earlier mission plans.
The approach is not final. NASA could choose Blue Origin’s Blue Moon lander for Artemis IV if SpaceX cannot demonstrate that its orbital refueling plan works or complete an uncrewed lunar landing mission by the end of next year, provided Blue Moon meets the required conditions in time.
Sources: Space.com.