Webb Space Telescope’s ‘Backbone’ Completed

Manufacture of the “backbone” of NASA’s James Webb Space Telescope, a backplane support frame (BSF) that is the largest optically stable cryostructure ever built, is completed and ready for integration, project contractors Northrop Grumman Corp. and ATK reported last week.

The telescope is a next-generation space observatory and successor to the Hubble Space Telescope. The most powerful space telescope ever built, the Webb will observe the most distant objects in the universe, provide images of the first galaxies formed and see unexplored planets around distant stars. A joint project of NASA, the European Space Agency and the Canadian Space Agency, it is scheduled to launch in 2018.

This x-ray diagram of NASA’s James Webb Space Telescope shows where the backplane support frame (BSF) is in relation to the whole observatory. The BSF is the ‘backbone’ of the observatory, the primary load-carrying structure for launch, and holds the science instruments. Courtesy of Northrop Grumman.

Measuring approximately 24 ×19.5 ×11 ft when fully deployed, and weighing 2180 lb, the structure will include the wing assemblies, the center section and the BSF. When combined with the center section and wings, the BSF will form the primary mirror backplane support structure (PMBSS), a platform that will hold the telescope’s beryllium mirrors, instruments and other elements weighing more than 7300 lb, or more than 300 percent its own weight.

The PMBSS will hold the 18-segment, 21-foot-diameter primary mirror nearly motionless while the telescope is peering into deep space.

“With the completion of the frame, the structural backbone of the observatory is now ready for integration,” said Gregory Young, acquisition manager for Northrop Grumman, which is under contract to NASA’s Goddard Space Flight Center in Greenbelt, Md., to design and develop the telescope’s optics, sunshield and spacecraft.

Technicians complete the center section of the backplane support frame for NASA’s James Webb Space Telescope at ATK’s facility in Magna, Utah. Courtesy of ATK.

The BSF was designed and fabricated at ATK facilities in Magna, Utah. ATK has begun final integration of the BSF to the previously completed center section to form the complete backplane; the newly assembled structure is on track to meet critical path program milestones when it is delivered to Marshall Space Flight Center in Huntsville, Ala., later this summer for extreme cryogenic thermal testing.

The PMBSS will then undergo structural static testing at Northrop Grumman’s facilities in Redondo Beach in early 2014 before NASA and the company ready the observatory for its 2018 launch.

For more information on the telescope project, visit: www.jwst.nasa.gov or www.northropgrumman.com/capabilities/jwst/pages/default.aspx