Ball Aerospace & Technologies Corp. has announced that the final six mirror segments for the James Webb Space Telescope have completed cryogenic temperature testing at NASA’s Marshall Space Flight Center. The final testing verifies that the 18-mirror composite primary mirror segments meet their combined wavefront error and radius of curvature requirements.
The Webb’s 18 mirror segments, as well as the secondary, tertiary and fine-steering mirrors, were produced by a Beryllium mirror development team led by Ball Aerospace. Team members included Materion (formerly Brush Wellman) in Elmore, Ohio; Axsys Technologies in Cullman, Ala.; L3 Tinsley in Richmond, Calif.; and QCI in Morristown, N.J. Completion of the cryogenic temperature tests at Marshall’s X-Ray and Cryogenic Facility (XRCF) marks a significant milestone in the challenging progress for NASA’s next great astrophysical space observatory. All 21 mirrors that comprise JWST telescope have now successfully completed final optical verification testing.
“Completion of cryogenic testing for the mirrors keeps the telescope on track and moving forward toward its 2018 launch date,” said Cary Ludtke, vice president and general manager for the Ball Aerospace Civil and Operational Space strategic business unit.
Earlier tests at XRCF measured distortion of each hexagonal beryllium mirror surface as it cools from room temperature to the Webb telescope’s on-orbit operating temperature of approximately 45 K (-380 deg F). This surface distortion was then mapped and subsequently removed in the final mirror polishing operations. The final cryogenic tests verified that the warm-to-cold surface distortion has been properly removed in final polishing. Once on orbit, the Wavefront Sensing and Control algorithm software, also developed by Ball, will calculate the optimum position of each of the 1.3-meter (per hexagonal side) mirrors, and then adjust positions to correct any errors. The individual mirror segments are phased on orbit using computer-controlled actuators that can adjust the position and shape of the mirrors to give the telescope a high quality, sharp image.
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. The James Webb Space Telescope mirror will be the largest ever flown in space and six times larger than Hubble’s mirror. The large, light-collecting area of the primary mirror allows superior viewing of extremely faint targets.
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.
Ball Corporation (NYSE:BLL) is a supplier of high quality packaging for beverage, food and household products customers, and of aerospace and other technologies and services, primarily for the U.S. government. Ball Corporation and its subsidiaries employ more than 14,500 people worldwide and reported 2010 sales of more than $7.6 billion. For the latest Ball news and for other company information, please visit http://www.ball.com.
