Inspecting the first gold coated primary mirror segment

Ball Aerospace optical technician Scott Murray inspects the first gold coated primary mirror segment on September 1, 2010, prior to cryogenic testing in the X-ray & Cryogenic Facility at NASA's Marshall Space Flight Center in Huntsville, Ala. The mirror was coated in gold by by Quantum Coating Incorporated.

A thin coating of gold, just about 3 grams for each of the 18 hexagons, is vaporized into a cloud and applied to the beryllium mirrors in a layer just 120 nanometers thick to improve the reflection of infrared light.