“The James Webb Space Telescope team has fully deployed the spacecraft’s 70-foot sunshield, a key milestone in preparing it for science operations.
The sunshield – about the size of a tennis court at full size – was folded to fit inside the payload area of an Arianespace Ariane 5 rocket’s nose cone prior to launch. The Webb team began remotely deploying the sunshield Dec. 28, 2021, three days after launch.
NASA will hold a media teleconference at 12:45 p.m. EST today, Tuesday, Jan. 4, to discuss the completion of this critical step. To participate by telephone, media must RSVP to Laura Betz at: email@example.com. Audio of the teleconference will also stream on the agency’s website.
“This is the first time anyone has ever attempted to put a telescope this large into space,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “Webb required not only careful assembly but also careful deployments. The success of its most challenging deployment – the sunshield – is an incredible testament to the human ingenuity and engineering skill that will enable Webb to accomplish its science goals.”
The five-layered sunshield will protect the telescope from the light and heat of the Sun, Earth, and Moon. Each plastic sheet is about as thin as a human hair and coated with reflective metal, providing protection on the order of more than SPF 1 million. Together, the five layers reduce exposure from the Sun from over 200 kilowatts of solar energy to a fraction of a watt.
This protection is crucial to keep Webb’s scientific instruments at temperatures of 40 kelvins, or under minus 380 degrees Fahrenheit – cold enough to see the faint infrared light that Webb seeks to observe.”