[meteorite-list] NASA Completes Mirror Polishing For James Webb Space Telescope

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 30 Jun 2011 10:59:17 -0700 (PDT)
Message-ID: <201106301759.p5UHxHeG010846_at_zagami.jpl.nasa.gov>

June 30, 2011

Trent Perrotto
Headquarters, Washington
trent.j.perrotto at nasa.gov
202-358-0321

Mary Blake
Northrop Grumman, Redondo Beach, Calif.
mary.blake at ngc.com
310-812-6291


RELEASE: 11-210

NASA COMPLETES MIRROR POLISHING FOR JAMES WEBB SPACE TELESCOPE

WASHINGTON -- Mirrors are a critical part of a telescope. The quality
is crucial, so completion of mirror polishing represents a major
milestone. All of the mirrors that will fly aboard NASA's James Webb
Space Telescope have been polished so the observatory can see objects
as far away as the first galaxies in the universe.

The Webb telescope is comprised of four types of mirrors. The primary
one has an area of approximately 25 square meters (29.9 square
yards), which will enable scientists to capture light from faint,
distant objects in the universe faster than any previous space
observatory. The mirrors are made of Beryllium and will work together
to relay images of the sky to the telescope's science cameras.

"Webb's mirror polishing always was considered the most challenging
and important technological milestone in the manufacture of the
telescope, so this is a hugely significant accomplishment," said Lee
Feinberg, Webb Optical Telescope manager at NASA's Goddard Space
Flight Center in Greenbelt, Md.

The mirrors were polished at the L3 Integrated Optical Systems -
Tinsley in Richmond, Calif. to accuracies of less than one millionth
of an inch. That accuracy is important for forming the sharpest
images when the mirrors cool to -400??F (-240??C) in the cold of space.

"The completion of the mirror polishing shows that the strategy of
doing the hardest things first has really paid off," said Nobel Prize
Winner John C. Mather, Webb's senior project scientist at Goddard.
"Some astronomers doubted we could make these mirrors."

After polishing, the mirrors are being coated with a microscopically
thin layer of gold to enable them to efficiently reflect infrared
light. NASA has completed coating 13 of 18 primary mirror segments
and will complete the rest by early next year. The 18 segments fit
together to make one large mirror 21.3 feet (6.5 meters) across.

"This milestone is the culmination of a decade-long process," said
Scott Willoughby, vice president and Webb Telescope Program manager
for Northrop Grumman Aerospace Systems. "We had to invent an entire
new mirror technology to give Webb the ability to see back in time."

Northrop Grumman Corp. in Redondo Beach, Calif. is the telescope's
prime contractor.

As the successor to the Hubble Space Telescope, the Webb telescope is
the world's next-generation space observatory. It is the most
powerful space telescope ever built. More than 75 percent of its
hardware is either in production or undergoing testing. The telescope
will observe the most distant objects in the universe, provide images
of the first galaxies ever formed and study planets around distant
stars. NASA, the European Space Agency and the Canadian Space Agency
are collaborating on this project.

For related images and more information about the mirrors, visit:

http://www.nasa.gov/topics/universe/features/webb-mirrors-done.html

To view the "Behind the Webb: Wax on, Wax Off" video explaining the
mirror polishing process, visit:

http://webbtelescope.org/webb_telescope/behind_the_webb/10

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

http://www.jwst.nasa.gov
        
-end-
Received on Thu 30 Jun 2011 01:59:17 PM PDT