OrbitalHub

NASA dicit:

In October 2019, technicians and engineers successfully performed a critical test on NASA’s James Webb Space Telescope by fully deploying and properly tensioning each of its five uniquely sized sunshield layers, putting them into the same positions they will have in space. To observe distant parts of the universe humans have never seen before, the Webb observatory is equipped with an arsenal of revolutionary technologies, making it the most sophisticated and complex space science telescope ever created. Among the most challenging of these technologies is the five-layer sunshield, designed to protect the observatory’s mirrors and scientific instruments from light and heat, primarily from the Sun. Due to the telescope’s size, shape and thermal performance requirements, the sunshield must be both big and complex. As if that’s not challenging enough, it also must be very lightweight, fit inside a standard 5-meter (16-foot) diameter rocket fairing, survive the perils of launch, and accurately deploy into its required shape, with only a single chance to get it right. Following Webb’s successful sunshield test within Northrop Grumman’s Redondo Beach, California facility, team members have begun the long process of perfectly folding the sunshield back into its stowed configuration for flight, which occupies a drastically smaller volume than when it is fully deployed.

Video Credit: Credit: NASA’s Goddard Space Flight Center/Mike McClare/Michael Starobin/Mike Menzel/Sophia Roberts