Ball Aerospace has shipped five James Webb space telescope (JWST) beryllium primary mirror segments to Nasa’s Marshall Space Flight Center for cryogenic temperature testing.

JWST will be a large telescope with a 6.5m beryllium primary mirror that will make infrared observations to study the history of the universe.

Each of the 18 hexagonal-shaped mirror assemblies that make up the primary mirror measures more than 1.3m across and weighs about 40kg after light weighting.

The mirrors will undergo two cryogenic temperature tests of which the first measures distortion of each mirror surface as it cools from room temperature to the Webb telescope’s on-orbit operating temperature of about -380°F.

The distortion is mapped and removed in the final mirror polishing operations, and the second test verifies that the warm-to-cold surface distortion has been removed in final polishing.

The first segment has undergone the first of the two tests, while the five shipped will undergo tests beginning this month. The process for all 18 JWST mirror segments will continue until 2011.

The space telescope is scheduled for launch in 2014.