On-orbit servicing (OOS) encompasses any operation performed on a satellite after it has been deployed, including inspection, refueling, repair, component replacement, and orbit adjustment. Northrop Grumman's MEV (Mission Extension Vehicle) demonstrated the first commercial servicing mission in 2020 by docking with an Intelsat GEO satellite to extend its life. Astroscale, Orbit Fab, and several other startups are building the next generation of servicing vehicles.
OOS promises to transform the economics of the satellite industry by enabling operators to extend the life of high-value assets rather than replacing them entirely. It also addresses the growing space debris problem by providing the capability to relocate dead satellites to graveyard orbits or deorbit them. DARPA and NASA are investing in robotic servicing technologies, and the concept of "gas stations in space" for on-orbit refueling is advancing toward commercial reality.