[meteorite-list] NASA's Webb Space Telescope Receives First Mirror Installation

[Ron Baalke]

November 25, 2015

RELEASE 15-226

NASA's Webb Space Telescope Receives First Mirror Installation 

NASA has successfully installed the first of 18 flight mirrors onto the James 
Webb Space Telescope, beginning a critical piece of the observatory's 
construction.

In the clean room at NASA's Goddard Space Flight Center in Greenbelt, 
Maryland this week, the engineering team used a robot arm to lift and lower 
the hexagonal-shaped segment that measures just over 4.2 feet (1.3 meters) 
across and weighs approximately 88 pounds (40 kilograms). After being pieced 
together, the 18 primary mirror segments will work together as one large 
21.3-foot (6.5-meter) mirror. The full installation is expected to be 
complete early next year.

"The James Webb Space Telescope will be the premier astronomical 
observatory of the next decade," said John Grunsfeld, astronaut and 
associate administrator of the Science Mission Directorate at NASA 
Headquarters in Washington. "This first-mirror installation milestone 
symbolizes all the new and specialized technology that was developed to 
enable the observatory to study the first stars and galaxies, examine the 
formation stellar systems and planetary formation, provide answers to the 
evolution of our own solar system, and make the next big steps in the search 
for life beyond Earth on exoplanets."

Several innovative technologies have been developed for the Webb Telescope, 
which is targeted for launch in 2018, and is the successor to NASA's Hubble 
Space Telescope. Webb will study every phase in the history of our 
universe, including the cosmos' first luminous glows, the formation of 
solar systems capable of supporting life on planets like Earth, and the 
evolution of our own solar system.

The 18 separate segments unfold and adjust to shape after launch. The mirrors 
are made of ultra-lightweight beryllium chosen for its thermal and mechanical 
properties at cryogenic temperatures. Each segment also has a thin gold 
coating chosen for its ability to reflect infrared light. The telescope's 
biggest feature is a tennis court sized five-layer sunshield that attenuates 
heat from the sun more than a million times.

"After a tremendous amount of work by an incredibly dedicated team across 
the country, it is very exciting to start the primary mirror segment 
installation process" said Lee Feinberg, James Webb Space Telescope optical 
telescope element manager at Goddard. "This starts the final assembly phase 
of the telescope."

The mirrors must remain precisely aligned in space in order for Webb to 
successfully carry out science investigations. While operating at 
extraordinarily cold temperatures between minus 406 and minus 343 degrees 
Fahrenheit, the backplane must not move more than 38 nanometers, 
approximately one thousandth the diameter of a human hair.

"There have many significant achievements for Webb over the past year, but 
the installation of the first flight mirror is special," said Bill Ochs, 
James Webb Space Telescope project manager. "This installation not only 
represents another step towards the magnificent discoveries to come from 
Webb, but also the culmination of many years of effort by an outstanding 
dedicated team of engineers and scientists."

The mirrors were built by Ball Aerospace & Technologies Corp., Boulder, 
Colorado. Ball is the principal subcontractor to Northrop Grumman for the 
optical technology and lightweight mirror system.

The James Webb Space Telescope is an international project led by NASA with 
its partners, ESA (European Space Agency) and the Canadian Space Agency. NASA 
works with the international science community to explore our solar system 
and beyond. We look to unravel mysteries that intrigue us all as we explore 
to answer big questions, like how did our solar system originate and change 
over time, and how did the universe begin and evolve, and what will be its 
destiny?

You can follow the mirror installation on a live webcam by visiting:

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

To learn more about the James Webb Space Telescope, visit:

http://www.nasa.gov/webb

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