NASA Moon Landing Needs More Boosters

The path to returning humans to the Moon is becoming increasingly defined by a specific logistical hurdle that has long eluded a precise public figure. For years, NASA has been tight-lipped about the exact number of orbital refueling flights necessary to send a crewed lander to the lunar surface and back, a metric that is critical to the success of the Artemis Program. The agency has historically preferred to keep this number vague to avoid setting hard expectations, but recent disclosures are shedding light on the scale of the undertaking.

The latest estimate places the requirement at twenty-two Starship launches. This figure emerged during a quarterly meeting of the NASA Aerospace Safety Advisory Panel held on Thursday. Panel member Charlie Precourt, a former NASA astronaut, discussed the risks associated with the Artemis Program and the specific challenges of landing humans on the Moon. His presentation highlighted the complexity of fueling a Starship-based lunar lander in low-Earth orbit, a process that requires multiple tanker flights to transfer liquid oxygen and methane before the vehicle can depart for the Moon.

This new number marks a significant shift from previous guidance. In 2023, Lisa Watson-Morgan, then-director of NASA’s Human Landing System, described the requirement as being in the "high single digits to the low double digits." That earlier estimate implied roughly a dozen launches, involving one depot Starship and approximately eleven tanker flights. More recently, other officials had suggested the number could reach the "high teens." The jump to twenty-two indicates that the operational requirements are more demanding than initially thought, or that the assumptions regarding vehicle efficiency have changed.

The variability in these estimates has been a source of tension for years. The underlying hope has always been that SpaceX would dramatically improve the lift capacity of its Starship rocket. Such an improvement would reduce the number of tanker flights needed to fully load the lunar lander. However, there are growing concerns among some NASA officials that these efficiency gains may not materialize soon enough to allow Starship to play a meaningful role in this decade’s lunar return efforts.

The discrepancy between the earlier "low double digits" and the current estimate of twenty-two underscores the fragility of the program's schedule. If the lift capacity does not improve as projected, the sheer volume of launches required becomes a major bottleneck. Each launch must be successful, and the coordination of multiple vehicles in orbit adds layers of complexity and risk to an already ambitious mission profile.

The Artemis Program relies heavily on this orbital refueling architecture. Without sufficient propellant in low-Earth orbit, the lunar lander cannot perform the necessary maneuvers to travel to the Moon, land on the surface, and return to lunar orbit. The number of launches is therefore not just a logistical detail but a direct indicator of mission feasibility within the current timeframe.

As the program moves forward, the focus will likely shift to validating these new estimates. The Aerospace Safety Advisory Panel’s discussion signals that safety and risk assessments are being updated to reflect the higher launch count. This may influence how NASA manages the development and testing phases of the Starship system in the coming months.

What happens next will depend on how NASA and SpaceX respond to this revised reality. If the number of required launches remains high, the pace of development and integration must accelerate to keep the decade-end goal alive. Stakeholders will be watching closely to see if the lift capacity improvements arrive in time to lower this number, or if the program must adjust its timeline to accommodate the current operational requirements.