The James Webb Space Telescope’s gold-plated, beryllium mirrors are beautiful feats of engineering From the 18 hexagonal primary mirror segments, to the perfectly circular secondary mirror, and even the slightly trapezoidal tertiary mirror and the intricate fine-steering mirror, each reflector went through a rigorous refinement process before it was ready to mount on the telescope. This flawless formation process was critical for Webb, which will use the mirrors to peer far back in time to capture the light from the first stars and galaxies. Webb will be a powerful time machine with infrared vision . Webb’s segmented primary mirror has a diameter of 6.6 meters (21.7 feet). Each of the 18 segments is 1.32 meters (4.3 feet) across. The area of the mirror is approximately 25 square meters (270 square feet) and the mass is 705 kilograms (1,550 pounds on Earth). ℹ️ A tiny rock fragment has hit the new James Webb Space Telescope's main mirror. The damage inflicted by the dust-sized micrometeoroid is producing a noticeable effect in the observatory's data but is not expected to limit the mission's overall performance. James Webb was launched in December to succeed the revolutionary - but now ageing - James Webb Space Telescope. Astronomers are due to release its first views of the cosmos on 12 July. The US space agency Nasa said these images would be no less stunning because of what's just happened.