Commerical Crew Program (CCP) Astronauts visit Aerojet Rocketdyn

NASA astronauts Suni Williams, from left, Eric Boe and Barry "Butch" Wilmore survey an RL10 engine as it stands in a vacuum chamber at Aerojet Rocketdyne's test stand in West Palm Beach, Florida. The engine will be one of two used for the Centaur upper stage during a United Launch Alliance Atlas V mission to launch Boeing's CST-100 Starliner on a flight test carrying a crew. The engine was test-fired as part of acceptance testing to confirm the engine is ready for flight.