Ball Aerospace begins final cryogenic testing of flight mirrors

Ball Aerospace & Technologies Corp. has delivered six of 18 James Webb Space Telescope mirror segments for cryogenic acceptance testing, to the Marshall Space Flight Center X-ray & Cryogenic Facility, Huntsville, Ala.

The first full set of coated mirrors will be mounted to a fixture and undergo final cryogenic protoflight testing inside Marshall's XRCF chamber. Ball Aerospace engineers will initiate round-the-clock testing on April 15, which will continue for eight weeks. This is the first of three acceptance tests for the flight mirror assemblies. Ball will test a second set of six mirror assemblies at Marshall in July, and a final set of six in the fall of 2011. 

"The kickoff for the final cryogenic testing of the mirrors has been eight years in the making," said Cary Ludtke, vice president and general manager for the Ball Aerospace Civil and Operational Space strategic business unit. "This milestone speaks to the disciplined and painstaking approach successfully employed by the development team and partners."

In addition to the primary mirror assemblies, Ball Aerospace will deliver the secondary flight mirror assembly in October. Protoflight testing of the tertiary and fine steering mirror assemblies will be complete in July, and the aft optics bench will also be fully assembled by October.

Ball Aerospace is the principal optical subcontractor for the JWST program, led by prime contractor Northrop Grumman Aerospace Systems, under contract to NASA Goddard Space Flight Center. Ball is responsible for developing the telescope optics, including the 18 beryllium mirror segment assemblies that comprise the primary mirror. Each mirror segment measures 1.32 meters (4.3 ft.) in diameter to form the 6.5-meter diameter (21.3 ft.) hexagonal Webb telescope, critical for future infrared observations. Each of the 18 hexagonal-shaped mirror assemblies weighs approximately 40 kilograms( 88 pounds) after light-weighting.

Ball Aerospace & Technologies Corp. supports critical missions of important national agencies such as the Department of Defense, NASA, NOAA and other U.S. government and commercial entities. The company develops and manufactures spacecraft, advanced instruments and sensors, components, data exploitation systems and RF solutions for strategic, tactical and scientific applications. For more information visit www.ballaerospace.com.