NASA and Pratt & Whitney Rocketdyne have successfully completed the heart of the J-2X upper stage rocket engine the turbomachinery assemblies for the first development engine off the production line.
The engine's turbomachinery consists of two turbopumps, each part pump and part turbine. Turbines provide the power to drive the pumps. One pump pushes high-pressure liquid oxygen, or oxidizer, and the other pumps liquid hydrogen fuel through the engine and to the engine's main injector. When the two meet, the fuels combine in a controlled high-pressure explosion producing the combustion needed to propel a launch vehicle to its journey to space.