WASHINGTON — NASA has outlined the operational order of operations for fueling SpaceX’s Starship Human Landing System (HLS) in Earth orbit ahead of Artemis IV, the program’s scheduled first crewed lunar landing.
Presented during an agency briefing in late October 2026, the updated flight sequence illustrates the multi-phase choreography required to stage and gas up the upper-stage lander in space before it departs for the Moon.
Refueling Projections and the 22-Launch Estimate
The operational blueprint arrives amid ongoing debate over how many preliminary tanker flights will be necessary to execute a crewed lunar sortie. While a summer 2021 Government Accountability Office (GAO) audit estimated that the lunar architecture could require up to 16 launches, recent panel assessments presented higher estimates. During an October 2026 public meeting, Charlie Precourt, a member of NASA’s Aerospace Safety Advisory Panel (ASAP), cautioned that fueling the lander could require as many as 22 launches.
SpaceX founder and Chief Executive Officer Elon Musk disputed that projection, stating on social media platform X that the actual number of refueling flights will be closer to six or eight. The disparity reflects varying engineering assumptions regarding Starship payload capacity, propellant boil-off rates during orbital loiter, and the operational efficiency of cryogenic fluid transfer between vehicles in low Earth orbit.
Orbital Depot Operations and Cryogenic Management
NASA’s concept graphic clarifies how off-planet propellant aggregation will function. Under the illustrated architecture, multiple Starship tanker variants will lift off from Earth to deliver liquid methane and liquid oxygen to a dedicated propellant depot loitering in low Earth orbit. Once the depot tanks are filled, the uncrewed Starship HLS upper stage will launch, dock with the orbital depot to receive its full propellant load, and initiate its trans-lunar injection burn toward lunar orbit.
Schedule and Path to Artemis IV Crewed Landing
Validating orbital refueling remains a critical technical milestone for NASA’s broader Artemis lunar exploration roadmap. Following the restructuring of Artemis III into a low Earth orbit docking and systems test flight, Artemis IV represents NASA’s first planned landing of astronauts at the lunar South Pole. Flight controllers and SpaceX engineers are scheduled to conduct an initial orbital cryogenic propellant transfer demonstration ahead of full uncrewed lunar test flights.
