GAO Report: SpaceX Starship Might Need to Shrink for NASA's Lunar Gateway Docking

A recent GAO report reveals SpaceX's Starship might need to be smaller to dock with NASA's lunar Gateway. The spacecraft's size challenges the station's mass and steering capabilities.

SpaceX's Starship Size Poses Challenges for NASA's Artemis Lunar Gateway Plans

According to a recent Government Accountability Office (GAO) report, the Starship lunar spacecraft developed by SpaceX for NASA's Artemis program may need to be smaller to dock with the agency's proposed lunar space station effectively. The GAO investigated the space station's mass constraints and determined that the combined mass of two of its primary components, the habitation and logistics outpost (HALO) and the power and propulsion element (PPE), exceeded their targeted values. Additionally, it was determined that the personal protective equipment (PPE) may not be capable of accurately steering the vehicle if it is in the presence of large vehicles, such as SpaceX's Starship dock. This is because the performance requirements established by NASA do not account for larger vehicles.

With the Artemis IV mission scheduled to launch in September 2028, the deployment of NASA's lunar space station, Gateway, by 2027 or before the launch of Artemis IV is of utmost importance. The Gateway must be in lunar orbit one year before the launch of Artemis IV to ensure all systems are operational before crew boarding.

According to the GAO, NASA's current baseline capability for Gateway's launch is December 2027, which is three months behind schedule. NASA will update Gateway's current cost and confidence level in September of this year to determine whether the launch of Artemis IV in September 2028 will enable the mission to achieve its objectives. According to Wccftech, the space agency has been responsible for managing hazards associated with the space station's communications network and habitability systems since the previous analysis was conducted last May.

GAO Warns of Mass Constraints in Gateway Program, NASA Explores Solutions for Starship Docking

The GAO's identification of mass as a significant constraint in the Gateway program is a serious concern. The combined mass of the space station's logistics and propulsion elements exceeds NASA's mass requirements, potentially impacting the station's missions. Due to the bulk of certain vehicles, the propulsion element may not steer the space station according to the mission profile, further exacerbating the situation.

Managing the Gateway's mass is complex, with potential trade-offs in the available options. Due to the increased mass, NASA may need to launch specific Gateway components separately to ensure the space station is positioned in the appropriate orbit. Alternatively, the mass could be decreased by eliminating components. However, both of these options come with their own trade-offs, highlighting the situation's complexity.

Ironically, Gateway's PPE cannot manage heavier spacecraft when docked with the station despite exceeding the mass requirements. This impacts the station's capacity to sustain its orbit and the appropriate orientation for communication with Earth. The PPE needs to be more for vehicles such as SpaceX's Starship, whose mass is 18 times greater than the PPE's design capability, even though it fulfills the requirements established during the design phase, according to NASA managers quoted by the GAO. Both are essential for the success of a mission.

Despite the challenges, NASA actively explores solutions to the Gateway space station's mass and steering constraints. The agency is considering having visiting vehicles share some of the PPE's labor for Starship to control the station. A software upgrade to optimize the station's thrusters is also being contemplated. Should these measures prove unsuccessful, NASA is prepared to modify the design of the PPE, albeit with potential additional schedule and cost constraints on the Gateway program.