NASA image release April 13, 2011 An engineer examines the Webb telescope primary mirror Engineering Design Unit segment in the clean room at NASA's Goddard Space Flight Center, Greenbelt, Md. It takes two unique types of mirrors working together to see farther back in time and space than ever before, and engineers at NASA's Goddard Space Flight Center have just received one of each type. Primary and Secondary Mirror Engineering Design Units (EDUs) have recently arrived at NASA's Goddard Space Flight Center in Greenbelt, Md. from Northrop Grumman Aerospace Systems in Redondo Beach, Calif. and are undergoing examination and testing. When used on the James Webb Space Telescope those two types of mirrors will allow scientists to make those observations. "The Primary mirror EDU will be used next year to check out optical test equipment developed by Goddard and slated to be used to test the full Flight Primary mirror," said Lee Feinberg, the Optical Telescope Element Manager for t