Elon Musk disputes NASA panel, says Moon lander needs 8 tankers

Elon Musk pushed back against a NASA advisory panel's calculation for lunar logistics on Thursday, stating that the number of tanker launches required to fuel a Moon lander is much lower than officials suggested. The dispute began during a quarterly meeting of the Aerospace Safety Advisory Panel, where members reviewed risks for the Artemis IV mission, which aims to return a crew to the Moon in 2028.

Charlie Precourt, a former NASA astronaut and panel member, identified orbital refueling as a primary risk for the mission. He cited a figure of 22 flights to fill the fuel depot needed for the SpaceX Starship lunar lander. Precourt told the panel that the team must keep a close eye on the numerous fueling operations required. His comments were shared by journalist Eric Berger on X, drawing a direct response from Musk.

Musk rejected the 22-flight number, calling it way too high. He estimated that the actual requirement would be between six and eight tanker launches. The discrepancy stems from different assumptions about Starship performance. The NASA panel appears to have based its math on the vehicle's current lift capacity, while Musk's range assumes a more capable version of the rocket.

The engineering challenge is driven by the physics of large rocket launches. Starship uses nearly all its propellant just to reach Earth orbit, so it cannot proceed to the Moon without a top-up. SpaceX plans to launch a tanker Starship first to act as an orbital depot. Subsequent tanker flights will dock with this depot to transfer remaining fuel. Once the depot is full, the crewed lunar lander will launch, dock, refuel, and depart for the Moon.

Each additional tanker flight adds time, cost, and risk to the mission timeline. Berger noted that even with a launch rate of two Starships per week by late 2027, filling a depot at the panel's 22-flight estimate would take about three months. A lower count would compress that window and reduce the number of complex orbital docking maneuvers required before astronauts leave Earth.

Musk has previously disputed similar estimates. In 2021, he described a government projection of 16 launches as extremely unlikely, predicting eight would be the maximum needed. Precourt acknowledged that Artemis IV involves many firsts for the hardware involved. He also praised NASA Administrator Jared Isaacman for working to clear obstacles for both SpaceX and Blue Origin, whose Blue Moon lander does not rely on orbital refueling for its initial flight.