Featured Research

from universities, journals, and other organizations

James Webb Space Telescope’s mirrors get 'shrouded'

Date:
June 7, 2012
Source:
NASA
Summary:
Earlier this year, NASA completed deep-freeze tests on the James Webb Space Telescope mirrors in a "shroud" at the X-ray & Cryogenic Facility (XRCF) at Marshall Space Flight Center in Huntsville, Ala.

In the photo, a batch of mirror segments sit on a stand that was placed inside a helium cooled shroud.
Credit: NASA

Earlier this year, NASA completed deep-freeze tests on the James Webb Space Telescope mirrors in a "shroud" at the X-ray & Cryogenic Facility (XRCF) at Marshall Space Flight Center in Huntsville, Ala.

Related Articles


All of the Webb's 18 main mirror segments were tested under conditions that they will experience when operating in space to verify they will work as expected. Tested in batches of six, the mirrors were transferred to the cryogenic testing chamber where they were plunged to a chilly -414 degrees Fahrenheit (-248 C). In the photo above, a batch of mirror segments sit on a stand that was placed inside a helium-cooled "shroud." The base of the shroud is visible in the lower left. The part that looks like a swing is a counterbalance weight for the crane that lifted the fully populated test stand into place.

"The large tube is the back of the helium shroud that will go around the mirrors and cool them," says Lee Feinberg, the NASA Optical Telescope Element Manager for the James Webb Space Telescope at the Goddard Space Flight Center in Greenbelt, Md., "The gaseous helium shroud sits inside of a liquid nitrogen shroud…which sits inside of a vacuum chamber. All three work together to create a vacuum and cold environment to test the mirrors."

That cold environment mimics the harsh cold of space. Once at sub-zero temperatures, the testing team measured the surface shape of the mirror segments to see how they performed at cryogenic temperatures. The team measured the mirror segments by using laser systems to illuminate them for reflection of the light back into a sensor. The sensor then measures the change in shape of the mirror as the temperature changes.

When fully deployed, the Webb's mirror will be over six times larger than that of the Hubble Space Telescope's mirror. It's designed to look farther away and further back in time, and will be able to detect light from distant galaxies.

But despite Webb's size, its segmented beryllium mirror technology is significantly lighter than Hubble's one-piece glass mirror technology. Each of the 18 hexagonal, gold-coated primary mirror segments is hollowed out and ribbed on the backside, which Feinberg explains "lightweights" them to reduce their mass while keeping their precise shape.

More information about the James Webb Space Telescope can be found at: http://www.jwst.nasa.gov/


Story Source:

The above story is based on materials provided by NASA. Note: Materials may be edited for content and length.


Cite This Page:

NASA. "James Webb Space Telescope’s mirrors get 'shrouded'." ScienceDaily. ScienceDaily, 7 June 2012. <www.sciencedaily.com/releases/2012/06/120607123555.htm>.
NASA. (2012, June 7). James Webb Space Telescope’s mirrors get 'shrouded'. ScienceDaily. Retrieved January 28, 2015 from www.sciencedaily.com/releases/2012/06/120607123555.htm
NASA. "James Webb Space Telescope’s mirrors get 'shrouded'." ScienceDaily. www.sciencedaily.com/releases/2012/06/120607123555.htm (accessed January 28, 2015).

Share This


More From ScienceDaily



More Space & Time News

Wednesday, January 28, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Asteroid's Moon Spotted During Earth Flyby

Asteroid's Moon Spotted During Earth Flyby

Rumble (Jan. 27, 2015) Scientists working with NASA&apos;s Deep Space Network antenna at Goldstone, California discovered an unexpected moon while observing asteroid 2004 BL86 during its recent flyby past Earth. Credit to &apos;NASA JPL&apos;. Video provided by Rumble
Powered by NewsLook.com
Water Fleas Prepare for Space Voyage

Water Fleas Prepare for Space Voyage

Reuters - Innovations Video Online (Jan. 26, 2015) Scientists are preparing a group of water fleas for a unique voyage into space. The aquatic crustaceans, known as Daphnia, can be used as a miniature model for biomedical research, and their reproductive and swimming behaviour will be tested for signs of stress while on board the International Space Station. Jim Drury went to meet the team. Video provided by Reuters
Powered by NewsLook.com
Mars Rover Opportunity Celebrates 11-Year Anniversary

Mars Rover Opportunity Celebrates 11-Year Anniversary

Rumble (Jan. 26, 2015) Eleven years ago NASA&apos;s Opportunity rover touched down on Mars for what was only supposed to be a 90-day mission. Since then it has traveled 25.9 miles (41.7 kilometers), further than any other off-Earth surface vehicle has ever driven. Credit to &apos;NASA&apos;. Video provided by Rumble
Powered by NewsLook.com
NASA's On Course To Take Pluto's Best Photo Ever

NASA's On Course To Take Pluto's Best Photo Ever

Newsy (Jan. 25, 2015) NASA&apos;s New Horizons probe is en route to snap a picture of Pluto this summer, but making sure it doesn&apos;t miss its one chance to do so starts now. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins