Tests under way on the sunshield for James Webb telescope

June 13, 2012
The five-layer James Webb Space Telescope sunshield consists of thin membranes made from a polymer-based film and supporting equipment such as spreader bars, booms, cabling, and containment shells. Designed to block solar light and keep the Observatory operating at cryogenic temperatures. Credit: NASA/Northrop Grumman

(Phys.org) -- NASA is testing an element of the sunshield that will protect the James Webb Space Telescope's mirrors and instruments during its mission to observe the most distant objects in the universe.

The sunshield will consist of five tennis court-sized layers to allow the Webb telescope to cool to its cryogenic operating temperature of minus 387.7 degrees Fahrenheit (40 Kelvin).

Testing began early this month at ManTech International Corp.'s Nexolve facility in Huntsville, Ala., using flight-like material for the sunshield, a full-scale test frame and hardware attachments. The test sunshield layer is made of Kapton, a very thin, high-performance plastic with a reflective metallic coating, similar to a Mylar balloon. Each sunshield layer is less than half the thickness of a sheet of paper. It is stitched together like a quilt from more than 52 individual pieces because manufacturers do not make Kapton sheets as big as a tennis court.

September 2009 artist conception of the James Webb Space Telescope, with the 5 layer sunshield stretched out in space. Credit: NASA

The tests are expected to be completed in two weeks.

"The conclusion of testing on this full size layer will be the final step of the sunshield's development program and provides the confidence and experience to manufacture the five flight layers," said Keith Parrish, Webb Sunshield manager at NASA's Goddard Flight Center in Greenbelt, Md.

During testing, engineers use a high-precision to measure the layer every few inches at room temperature and pressure, creating a 3D map of the material surface, which is curved in multiple directions. The map will be compared to computer models to see if the material behaved as predicted, and whether critical clearances with adjacent hardware are achieved.

The test will be done on all five layers to give engineers a precise idea of how the entire sunshield will behave once in orbit. Last year, a one-third-scale model of the sunshield was tested in a chamber that simulated the it will experience in space. The test confirmed the sunshield will allow the telescope to cool to its operating temperature.

After the full-size sunshield layers complete testing and model analysis, they will be sent to Northrop Grumman in Redondo Beach Calif., where engineers verify the process of how the layers will unfurl in space. There the layers will be folded, much like a parachute, so they can be safely stowed for launch.

The Webb is the world's next-generation space observatory and successor to the Hubble Space Telescope. The most powerful space telescope ever built, Webb will provide images of the very first galaxies ever formed, and explore planets around distant stars. The Webb is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

Explore further: Tests under way on the sunshield for Webb telescope

Related Stories

Tests under way on the sunshield for Webb telescope

September 19, 2011

NASA is testing an element of the sunshield that will protect the James Webb Space Telescope's mirrors and instruments during its mission to observe the most distant objects in the universe.

James Webb Space Telescope: A year of achievement and success

January 9, 2012

The James Webb Space Telescope marked a year of significant progress in 2011 as it continues to come together as NASA's next generation space telescope. The year brought forth a pathfinder backplane to support the large primary ...

Recommended for you

Discovery of an extragalactic hot molecular core

September 29, 2016

Astronomers have discovered a 'hot molecular core', a cocoon of molecules surrounding a newborn massive star, for the first time outside our Galaxy. The discovery, which marks the first important step for observational studies ...

Rosetta measures production of water at comet over two years

September 29, 2016

Over the past two years, Rosetta has kept a close eye on many properties of Comet 67P/Churyumov-Gerasimenko, tracking how these changed along the comet's orbit. A very crucial aspect concerns how much water vapour a comet ...

Rosetta: beginning of the end for Europe's comet craft

September 29, 2016

Europe was poised Thursday to crashland its Rosetta spacecraft on a comet it has stalked for over two years, joining robot lander Philae on the cosmic wanderer's icy surface in a final suicide mission.

'Pandora's Cluster' seen by Spitzer

September 29, 2016

This image of galaxy cluster Abell 2744, also called Pandora's Cluster, was taken by the Spitzer Space Telescope. The gravity of this galaxy cluster is strong enough that it acts as a lens to magnify images of more distant ...

The frontier fields: Where primordial galaxies lurk

September 28, 2016

In the ongoing hunt for the universe's earliest galaxies, NASA's Spitzer Space Telescope has wrapped up its observations for the Frontier Fields project. This ambitious project has combined the power of all three of NASA's ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.