Webb Telescope?s First Primary Mirror Meets Cold Temperature Specifications

The James Webb Space Telescope reached a mission-readiness landmark today when its first primary mirror segment was cryo-polished to its required prescription as measured at operational cryogenic temperatures. This achievement sets the stage for a successful polishing process for the remaining 18 flight mirror segments.

Northrop Grumman Corporation is leading Webb?s design and development effort for NASA?s Goddard Space Flight Center, Greenbelt, Md.


Cryogenic polishing, or cryo-null  [...]

Full story at http://spacefellowship.com/news/art18876/webb-telescope-s-first-primary-mirror-meets-cold-temperature-specifications.html