All Space and Rocket Propulsion

Rocket engines and spacecraft propulsion systems that move a vehicle by expelling propellant rather than by turning a wheel, propeller or rotor, from early liquid-fuel rocket motors through the staged engines that launch orbital and interplanetary missions. Belongs here: any named rocket engine or spacecraft propulsion system considered on its own engineering merits. Does not belong here: the launch vehicle or spacecraft the engine powers, tracked as a vehicle entity under Spacecraft and Launch Vehicles.