The Rocketdyne division of Pratt & Whitney is being sold for $550 million to GenCorp., a northern California aerospace and defense company.

Canoga Park-based Rocketdyne has been a San Fernando Valley mainstay for more than 50 years having developed and built the rockets that took astronauts to the moon during the Apollo missions and the main engines for the Space Shuttle.

Rocketdyne employs 1,500 workers at two campuses in the Valley – one on Canoga Avenue and another at DeSoto Avenue and Nordhoff Street.

"We see great strategic value in this transaction for the country, our customers, partner supply base and our shareholders," GenCorp Chief Executive Officer Scott Seymour said in a prepared statement. "The combined enterprise will be better positioned to compete in a dynamic, highly competitive marketplace, and provide more affordable products for our customers."

The deal is expected to close in early 2013 and Rocketdyne will remain a separate company until then.

During the transition process, Rocketdyne will focus on delivering on customer commitments, reducing costs and improving efficiencies and ensuring a safe, supportive work environment for our employees, the company said in a statement.

Rocketdyne has provided engines for five rocket launches this year and has done testing on the development RS68A engine and the J2X engine.

GenCorp and Pratt & Whitney Rocketdyne have complementary products and technology services making for a combined company that will be a critical contributor to our nation’s strategic access to space, Rocketdyne said in its statement.

GenCorp. is considered an industry leader in rocket propulsion technology. The company’s Aerojet rocket and missile propulsion division dates back to the 1930s and has done work for the U.S. Air Force and Navy.

United Technologies, the parent company of Pratt & Whitney, announced in March it was selling the Rocketdyne division and two other business units to finance its acquisition of Goodrich Corp.

Mark R. Madler