. 24/7 Space News .
JWST Testing On Horizon

Given history with a certain other billion dollar space telescope, pre-flight testing of the James Webb Space Telescope will be rigorous to say the least
by S. Jenise Veris
for Aerospace Frontiers
Cleveland - Apr 13, 2004
Glenn engineers are gearing up the Space Power Facility (SPF) at Plum Brook to meet a challenging schedule of testing for the James Webb Space Telescope (JWST). It is a new kind of space telescope with a very large, infrared-optimized, primary mirror that will capture more light and resolve more distant objects than any other space-based telescope designed thus far.

Building on the success of Hubble, JWST is the first of the next generation of space telescopes designed to further our understanding of how the universe developed following the Big Bang. Understanding this process, through the formation of galaxies, stars, and planets, is a critical step in understanding the abundance of life on Earth and possibly elsewhere.

The telescope will be constructed using advanced, extremely lightweight mirrors that can be folded up to fit into the nose cone of a rocket. Once on orbit, the mirror will unfold with the help of computer-controlled actuators designed to work in extremely cold space temperatures (~30 to 100 Kelvin).

JWST will have an 18-segment, 6.5-meter primary mirror that can adjust in shape to obtain sharp, high-quality images. The telescope will maintain an orbit at the Earth-Sun Lagrange point (L2), approximately 1.5 million kilometers from Earth. Being the world's largest space environment simulation chamber, Glenn's SPF will provide the right size and environment to integrate, test, and align the space-based observatory.

"The sheer size of our facility provides flexibility in the design of a test, and its extraordinary vibrational stability is crucial for enabling critical optical measurements for a structure of this size," said Richard Kunath, chief, Plum Brook Management Office.

"A number of upgrades were also made over the past year to ensure a safe environment for testing JWST, including the replacement of 16 oil diffusion pumps (vacuum pumps that are used to achieve the high vacuum level in SPF) with 10 cryogenic pumps. These pumps provide the same function as the oil diffusion pumps, but without the use of silicon oil. The modification was made to ensure that there was no risk of contaminating the cryogenic optics of the telescope with silicon oil and damaging them."

Subsequent meetings with the JWST project office at Goddard Space Flight Center and the prime contractor Northrup-Grumman have revealed additional pretesting issues, such as cleaning and decontaminating the SPF vacuum chamber for the ultralow contamination levels that are needed to successfully accomplish this first-of-its-kind testing.

Frances Borato, Robert Puzak, Robin Brown, and Mark Woodling from the Engineering and Technical Services Directorate make up the small group of engineers who will identify the SPF upgrades needed to initiate testing; however, the Glenn JWST test team is still being formed.

"This project requires some very specialized expertise. We are in the process of putting together a Glenn JWST testing team to develop the designs and cost estimates of the clean rooms required for testing, as well as the modification of our cryogenic shrouds, which we will operate using helium in order to achieve the 37 K testing temperatures required," explained Jerry Carek, SPF manager.

"Some of the things we need to do include installation of very large clean rooms�Class 10,000 to 100,000�and the design and construction of the world's largest helium- cooled shroud system. Specialized thermal systems must be used to get down to �410 �F to simulate the extreme cold conditions of space. Once we upgrade the SPF we will have created the Nation's largest cryogenic optics testing facility," he added.

Northrup-Grumman and Kodak have already done some initial design work on the JWST observatory test stand and the issues surrounding how to integrate the cryoshrouds into the design, as well as how to decontaminate the structure, are being investigated.

Most of the facility buildup will take place between 2005 and 2006, with test hardware and test support equipment all arriving in 2006. Actual testing will begin in 2008 and continue through 2010.

Related Links
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express

Hubble's Successor - UK Takes A Leading Role
London - Mar 29, 2004
The Hubble Space Telescope has brought the wonder and spectacle of the Universe into every home. Its successor, the James Webb Space Telescope (JWST) due to be launched in 2011, will have a 6.5 metre diameter mirror - 2.5 times larger than Hubble's - enabling it to produce even sharper and more spectacular images from the farthest depths of the cosmos.



Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only














The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.