New video shows Webb Telescope first mirror installation

A new video from NASA shows the successful installation of the first of 18 flight mirrors onto the James Webb Space Telescope Structure, at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The installation of the first mirror is the beginning a critical phase of the observatory's construction. 

In the 1 minute and 8 second video, viewers will see how an engineering team used a robotic arm to lift and lower the hexagonal-shaped segment that measures just over 4.2 feet (1.3 meters) across and weighs approximately 88 pounds (40 kilograms). After being pieced together, the 18 primary mirror segments will work together as one large 21.3-foot (6.5-meter) mirror. The full installation is expected to be complete early in 2016.

The James Webb Space Telescope is the scientific successor to NASA's Hubble Space Telescope. It will be the most powerful space telescope ever built. Webb is an international project led by NASA with its partners, the European Space Agency and the Canadian Space Agency.