The Defense Innovation Unit (DIU), a US Department of Defense agency, is exploring how SpaceX's Starship vehicle can be used to support a broader architecture of in-space refueling. This initiative, spearheaded by Gary Henry, a senior adviser at DIU and a former SpaceX executive, aims to leverage Starship's in-space refueling capabilities for a wider range of users.
Starship's design relies on in-space propellant transfer for missions beyond Earth orbit, such as lunar voyages. "Tanker" Starships would deliver liquid oxygen and methane propellants to an orbital depot, which would then refuel Starships for deep-space travel. This approach, according to Henry, "unlocks the solar system" by providing a significant velocity boost to spacecraft.
DIU is investigating how this architecture could be utilized beyond Starship, potentially establishing standards for broader space operations. The agency is also exploring the use of Starship for "novel responsive space delivery," which involves delivering payloads from orbit to the ground. This concept aligns with the Air Force Research Lab's Vanguard program, which focuses on point-to-point transportation using rocket cargo.
While the US military has expressed interest in in-space refueling, concerns remain about its budget priority. However, Henry emphasizes the strategic importance of refueling capabilities for maneuvering in space, stating that it could be a key factor in deterring and winning conflicts in orbit.
DIU's approach to utilizing commercial capabilities like Starship emphasizes non-interference and additive contributions to the broader space community. The agency's exploration of Starship's refueling and delivery capabilities highlights the growing interest in leveraging commercial technologies for defense and space exploration.