[meteorite-list] NASA's Webb Telescope Gets Its Wings

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 15 Mar 2013 13:46:20 -0700 (PDT)
Message-ID: <201303152046.r2FKkKSE029194_at_zagami.jpl.nasa.gov>

March 15, 2013

J.D. Harrington
Headquarters, Washington
202-358-5241
j.d.harrington at nasa.gov

Christina Thompson
Northrop Grumman Corporation, Redondo Beach, Calif.
310-812-2375
christina.thompson at ngc.com

Jennifer Bowman
ATK, Magna, Utah
435-279-3159
jennifer.bowman at atk.com

RELEASE: 13-072

NASA'S WEBB TELESCOPE GETS ITS WINGS

WASHINGTON -- A massive backplane that will hold the primary mirror of
NASA's James Webb Space Telescope nearly motionless while it peers
into space is another step closer to completion with the recent
assembly of the support structure's wings.

The wings enable the mirror, made of 18 pieces of beryllium, to fold
up and fit inside a 16.4-foot (5-meter) fairing on a rocket, and then
unfold to 21 feet in diameter after the telescope is delivered to
space. All that is left to build is the support fixture that will
house an integrated science instrument module, and technicians will
connect the wings and the backplane's center section to the rest of
the observatory. The center section was completed in April 2012.

"This is another milestone that helps move Webb closer to its launch
date in 2018," said Geoff Yoder, NASA's James Webb Space Telescope
program director, NASA Headquarters, Washington.

Designed, built and set to be tested by ATK at its facilities in
Magna, Utah, the wing assemblies are extremely complex, with 900
separate parts made of lightweight graphite composite materials using
advanced fabrication techniques. ATK assembled the wing assemblies
like a puzzle with absolute precision. ATK and teammate Northrop
Grumman of Redondo Beach, Calif., completed the fabrication.

"We will measure the accuracy down to nanometers -- it will be an
incredible engineering and manufacturing challenge," said Bob
Hellekson, ATK's Webb Telescope program manager. "With all the new
technologies that have been developed during this program, the Webb
telescope has helped advance a whole new generation of highly skilled
ATK engineers, scientists and craftsmen while helping the team create
a revolutionary telescope."

When fully assembled, the primary mirror backplane support structure
will measure about 24 feet by 21 feet and weigh more than 2,000
pounds. The backplane must be very stable, both structurally and
thermally, so it does not introduce changes in the primary mirror
shape, and holds the instruments in a precise position with respect
to the telescope. While the telescope is operating at a range of
extremely cold temperatures, from minus 406 to minus 360 degrees
Fahrenheit, the backplane must not vary more than 38 nanometers
(about one one-thousandth the diameter of a human hair). The thermal
stability requirements for the backplane are unprecedented.

"Our ATK teammates demonstrated the thermal stability on test articles
before building the wing assemblies with the same design, analysis,
and manufacturing techniques. One of the test articles ATK built and
tested is actually larger than a wing," said Charlie Atkinson, deputy
Webb Optical Telescope Element manager for Northrop Grumman in
Redondo Beach, Calif. "The mirrors are attached to the wings, as well
as the rest of the backplane support structure, so the alignment is
critical. If the wings distort, then the mirror distorts, and the
images formed by the telescope would be distorted."

The James Webb Space Telescope is the successor to NASA's Hubble Space
Telescope. It will be the most powerful space telescope ever built
and observe the most distant objects in the universe, provide images
of the first galaxies formed and see unexplored planets around
distant stars. The Webb telescope is a joint project of NASA, the
European Space Agency and the Canadian Space Agency.

For the news release on the completion of the center section of the
backplane, visit:

http://go.nasa.gov/Zuggpq

For a "Behind the Webb" series video about the backplane, visit:

http://go.nasa.gov/Zugltr

For more information about the James Webb Space Telescope, visit:

http://www.jwst.nasa.gov
        
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Received on Fri 15 Mar 2013 04:46:20 PM PDT