Short answers, pulled from the story.
Pratt & Whitney Rocketdyne formed in 2005 following a merger between Pratt & Whitney Space Propulsion and Boeing Rocketdyne Propulsion & Power. The company established its headquarters in Canoga Park, Los Angeles, California.
Pratt & Whitney Rocketdyne developed the RL10 engine, the RS-68 engine, and the RS-25 engine as core capabilities in liquid propellant technology during the early twenty-first century. These three engines represented major contributions to space exploration programs including the Saturn I rocket, Delta IV launch vehicle, and Space Shuttle program.
The SJ61 engine operated by Pratt & Whitney Rocketdyne achieved speeds exceeding Mach 5 while flying aboard the Boeing X-51 hypersonic demonstration vehicle. This dual-mode ramjet and scramjet design combined different propulsion modes to validate concepts for future military and commercial applications.
United Technologies Corporation initiated plans to divest Pratt & Whitney Rocketdyne in July 2012 and finalized the transfer of ownership in June 2013. GenCorp Inc. purchased the division and merged it with its existing Aerojet operations to create the new entity known as Aerojet Rocketdyne.