[meteorite-list] NASA's James Webb Space Telescope Primary Mirror Fully Assembled

[Ron Baalke]

February 04, 2016

RELEASE 16-013

NASA's James Webb Space Telescope Primary Mirror Fully Assembled

The 18th and final primary mirror segment is installed on what will be the 
biggest and most powerful space telescope ever launched. The final mirror 
installation Wednesday at NASA's Goddard Space Flight Center in Greenbelt, 
Maryland marks an important milestone in the assembly of the agency's James 
Webb Space Telescope.

"Scientists and engineers have been working tirelessly to install these 
incredible, nearly perfect mirrors that will focus light from previously 
hidden realms of planetary atmospheres, star forming regions and the very 
beginnings of the Universe," said John Grunsfeld, associate administrator 
for NASA's Science Mission Directorate in Washington. "With the mirrors 
finally complete, we are one step closer to the audacious observations that 
will unravel the mysteries of the Universe."

Using a robotic arm reminiscent of a claw machine, the team meticulously 
installed all of Webb's primary mirror segments onto the telescope structure. 
Each of the hexagonal-shaped mirror segments measures just over 4.2 feet (1.3 
meters) across -- about the size of a coffee table -- and weighs 
approximately 88 pounds (40 kilograms). Once in space and fully deployed, the 
18 primary mirror segments will work together as one large 21.3-foot diameter 
(6.5-meter) mirror.

"Completing the assembly of the primary mirror is a very significant 
milestone and the culmination of over a decade of design, manufacturing, 
testing and now assembly of the primary mirror system," said Lee Feinberg, 
optical telescope element manager at Goddard. "There is a huge team across 
the country who contributed to this achievement."

While the primary mirror installation may be finished on the tennis 
court-sized infrared observatory, there still is much work to be done.

"Now that the mirror is complete, we look forward to installing the other 
optics and conducting tests on all the components to make sure the telescope 
can withstand a rocket launch," said Bill Ochs, James Webb Space Telescope 
project manager. "This is a great way to start 2016!"

The mirrors were built by Ball Aerospace & Technologies Corp., in Boulder, 
Colorado. Ball is the principal subcontractor to Northrop Grumman for the 
optical technology and optical system design. The installation of the mirrors 
onto the telescope structure is performed by Harris Corporation, a 
subcontractor to Northrop Grumman. Harris Corporation leads integration and 
testing for the telescope.

"The Harris team will be installing the aft optics assembly and the 
secondary mirror in order to finish the actual telescope," said Gary 
Matthews, director of Universe Exploration at Harris Corporation. "The 
heart of the telescope, the Integrated Science Instrument Module, will then 
be integrated into the telescope. After acoustic, vibration, and other tests 
at Goddard, we will ship the system down to Johnson Space Center in Houston 
for an intensive cryogenic optical test to ensure everything is working 
properly."

The James Webb Space Telescope is the scientific successor to NASA's Hubble 
Space Telescope. It will be the most powerful space telescope ever built. 
Webb will study many phases in the history of our universe, including the 
formation of solar systems capable of supporting life on planets similar to 
Earth, as well as the evolution of our own solar system. It's targeted to 
launch from French Guiana aboard an Ariane 5 rocket in 2018. Webb is an 
international project led by NASA with its partners, ESA (European Space 
Agency) and the Canadian Space Agency.

To watch the Webb telescope being built at Goddard, visit the "Webb-cam" page 
at:

http://www.jwst.nasa.gov/webcam.html


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