James Webb Space Telescope (JWST) - Thermal Shield - JWST sunshield: Thermal Shield Deployment to...

James Webb Space Telescope (JWST) - Thermal Shield - JWST sunshield: Thermal Shield Deployment to Northrop Grumann, California, July 2014. The JWST will replace the Hubble Space Telescope in 2018. The Sunshield on Nasa's James Webb Space Telescope is the largest part of the observatory - five layers of thin membrane that must unfurl reliably in space to precise tolerances. Last week, for the first time, engineers stacked and unfurled a full-sized test unit of the Sunshield and it worked perfectly. The Sunshield is about the length of a tennis court, and will be folded up like an umbrella around the Webb telescope's mirrors and instruments during launch. Once it reaches its orbit, the Webb telescope will receive a command from Earth to unfold, and separate the Sunshield's five layers into their precisely stacked arrangement with its kite-like shape