See: https://en.wikipedia.org/wiki/Raptor_prototype_upper-stage_engine https://en.wikipedia.org/wiki/Raptor_prototype_upper-stage_e... While there's no money i

See: https://en.wikipedia.org/wiki/Raptor_prototype_upper-stage_engine https://en.wikipedia.org/wiki/Raptor_prototype_upper-stage_e... While there's no money in this contract to develop the upper stage itself, only money for the engine, it's still a source.