The sunshield for NASA’s James Webb Space Telescope passed a test critical to preparing the observatory for its 2021 launch. Technicians and engineers fully deployed and tensioned each of the sunshield's five layers, successfully putting the sunshield into the same position it will be in when it is 1 million miles from Earth. 

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, which is designed to protect the observatory's mirrors and scientific instruments from light and heat, primarily from the sun.

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