NASA - James Webb Space Telescope Mirror 'Cans'

The powerful primary mirrors of the James Webb Space Telescope will be able to detect the light from distant galaxies. 

The manufacturer of those mirrors, Ball Aerospace & Technologies Corp. of Boulder, Colo., recently celebrated their successful efforts as mirror segments were packed up in special shipping canisters (cans) for shipping to NASA.

The Webb telescope has 21 mirrors, with 18 primary mirror segments working together as one large 21.3-foot (6.5-meter) primary mirror.

The mirror segments are made of beryllium, which was selected for its stiffness, light weight and stability at cryogenic temperatures. 

Bare beryllium is not very reflective of near-infrared light, so each mirror is coated with about 0.12 ounce of gold.

Beryllium increases hardness and resistance to corrosion when alloyed to aluminium, cobalt, copper (notably beryllium copper), iron and nickel. 

In structural applications, high flexural rigidity, thermal stability, thermal conductivity and low density (1.85 times that of water) make beryllium a quality aerospace material for high-speed aircraft, missiles, space vehicles and communication satellites.

Image Credit: Ball Aerospace