[meteorite-list] NASA's Webb Telescope's Last Backbone Component Completed

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 14 Jun 2013 15:59:12 -0700 (PDT)
Message-ID: <201306142259.r5EMxCPu029585_at_zagami.jpl.nasa.gov>

June 14, 2013

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

Christina Thompson
Northrop Grumman Corp., 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: 13-184

NASA'S WEBB TELESCOPE'S LAST BACKBONE COMPONENT COMPLETED

WASHINGTON -- Assembly of the backbone of NASA's James Webb Space
Telescope, the primary mirror backplane support structure, is a step
closer to completion with the recent addition of the backplane
support frame, a fixture that will be used to connect all the pieces
of the telescope together.

The backplane support frame will bring together Webb's center section
and wings, secondary mirror support structure, aft optics system and
integrated science instrument module. ATK of Magna, Utah, finished
fabrication under the direction of the observatory's builder,
Northrop Grumman Corp.

The backplane support frame also will keep the light path aligned
inside the telescope during science observations. Measuring 11.5 feet
by 9.1 feet by 23.6 feet and weighing 1,102 pounds, it is the final
segment needed to complete the primary mirror backplane support
structure. This structure will support the observatory's weight
during its launch from Earth and hold its18-piece, 21-foot-diameter
primary mirror nearly motionless while Webb peers into deep space.

ATK has begun final integration of the backplane support frame to the
backplane center section, which it completed in April 2012 and two
backplane wing assemblies, which it completed in March.

"Fabricating and assembling the backplane support frame of this size
and stability is a significant technological step as it is one of the
largest cryogenic composite structures ever built," said Lee
Feinberg, James Webb Space Telescope optical telescope element
manager at NASA's Goddard Space Flight Center in Greenbelt, Md.

The frame, which was built at room temperature but must operate at
temperatures ranging from minus 406 degrees to minus 343 degrees
Fahrenheit, will undergo extremely cold, or cryogenic, thermal
testing at NASA's Marshall Space Flight Center in Huntsville, Ala.
The backplane support frame and primary mirror backplane support
structure will shrink as they cool down in space. The tests,
exceeding the low temperatures the telescope's backbone will
experience in space, are to verify the components will be the right
size and operate correctly in space.

The primary mirror backplane support structure consists of more than
10,000 parts, all designed, engineered and built by ATK. The support
structure will measure about 24 feet tall, 19.5 feet wide and more
than 11 feet deep when fully deployed, but weigh only 2,138 pounds
with the wing assemblies, center section and backplane support frame
attached. When the mission payload and instruments are installed, the
fully populated support structure will support more than 7,300
pounds, more than three times its own weight.

The primary mirror backplane support structure also will meet
unprecedented thermal stability requirements to minimize heat
distortion. While the telescope is operating at a range of extremely
cold temperatures, from minus 406 degrees to minus 343 degrees
Fahrenheit, the backplane must not vary more than 38 nanometers
(approximately 1 one-thousandth the diameter of a human hair).

The primary backplane support structure is made of lightweight
graphite materials using and advanced fabrication techniques. The
composite parts are connected with precision metallic fittings made
of invar and titanium.

"The ATK team is providing program hardware that is arguably the
largest and most advanced cryogenic structure ever built," said Bob
Hellekson, ATK's Webb telescope program manager.

The assembled primary backplane support structure and backplane
support frame are scheduled for delivery to Marshall later this year
for the extreme cryogenic thermal testing. They will undergo
structural static testing at Northrop Grumman's facilities in Redondo
Beach, Calif. in early 2014, and then be combined with the wing
assemblies.

The James Webb Space Telescope, the successor to NASA's Hubble Space
Telescope, will be the most powerful space telescope ever built. It
will 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 more information about 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 14 Jun 2013 06:59:12 PM PDT