Beryllium Mirror Segment
Northrop Grumman Corporation's Space Technology sector is the prime contractor leading the design and development of the James Webb Space Telescope (JWST). Following a thorough and detailed evaluation, beryllium was selected as the material for the JWST primary mirror. A technician is shown mounting an alignment fiducial on a hexagonal beryllium mirror segment, which is approximately as large as the JWST flight mirror. It was developed under the Advanced Mirror System Demonstrator program (AMSD). AMSD was funded by a multiagency group to address the improvements in mirror materials, design and cycle times necessary to fabricate primary mirrors for future missions. The mirror segment stands in a support and actuation system where it was polished.
Credit: Northrop Grumman