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our most powerful window in the universe

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is nearing final assembly

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a 21 foot diameter segmented array of

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mirrors is the heart of nasa's james

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webb space telescope

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this powerful successor to the hubble

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space telescope

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will allow humans to see farther into

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the universe than ever before

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this herculean effort has pulled

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together technical experts from across

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the nation

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the mirror odyssey begins in a mine

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where the precious metal beryllium is

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extracted

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beryllium is the choice for mere

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material because it is lightweight and

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stable

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at the cold temperatures of space

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the beryllium powder is cast into four

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foot wide hexagonal mirror segments

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they are precisely ground and polished

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to a precision a thousand times

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smaller than the thickness of a human

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hair

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the mirrors are then tested to simulate

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the cold of deep space

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at minus 400 degrees fahrenheit

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mirrors are next coated with a very thin

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layer of gold

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which is needed to efficiently reflect

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infrared light to the telescope's

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cameras

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the mirrors are then vibrated to see if

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they can survive the rigors of launch

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at present the mirrors are nearly

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completed they are ready to be

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positioned on a giant skeletal frame

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cameras and other instruments will be

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added to the rear

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of this back plane the telescope will

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then be rolled into the giant thermal

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vacuum

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chamber used to test the apollo lunar

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spacecraft

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after that the two-story high optical

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telescope assembly

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will be attached to a tennis court size

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sun shape

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designed to deflect heat from the sun

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the telescope's gold mirrors will be

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used to seek our cosmic origins

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by seeing earliest galaxies and perhaps