DARPA Orbital Express (2007)
DARPA's Orbital Express program demonstrated autonomous satellite refueling and servicing in orbit, with the ASTRO spacecraft rendezvousing and docking with the NextSat target satellite repeatedly over several months.
The program proved technical feasibility of fully autonomous on-orbit servicing and docking.
It set the baseline for what autonomous RPO requires, but relied on custom-built, high-cost military systems — exactly what Momentus is trying to replace.
Orbital Express showed the capability is possible but expensive. Momentus's demonstration is the counter-example: commercial parts doing the same class of work at a fraction of the cost.
