This unfolding of the pallets marks the beginning of Webb’s major structural deployments.
The James Webb Space Telescope launched on December 25 has now passed the altitude of the Moon and is cruising on to its destination – the second Lagrange point (L2). JWST will be positioned about a million miles from Earth and will orbit the Sun.
On December 28, at approximately 1:21 pm EST (11:51 pm IST), the James Webb Space Telescope began the first step in the sunshield deployment phase. The process was completed at approximately 7:27 pm EST (5:57 am IST on December 29).
“While the actual motion to lower the forward pallet from its stowed to its deployed position took only 20 minutes, and the lowering of the aft pallet took only 18 minutes, the overall process took several hours for each because of the dozens of additional steps required,” NASA said in a release.
The additional steps included monitoring structural temperatures, turning on heaters to warm the key components, configuring electronics and software. This unfolding of the pallets marks the beginning of Webb’s major structural deployments. Such deployments will continue till January 2.
Today, the two-metre Deployable Tower Assembly (DTA) will be deployed. NASA said that this movement/distance provides the needed separation between the spacecraft and telescope to allow for better thermal isolation and to allow room for the sunshield membranes to unfold.
On January 1, the five-layered sunshield made of a material called Kapton will begin unfolding. The sunshield helps the telescope to cool down to a temperature below -223°C.
“The five layers are needed to block and redirect enough heat to get the telescope down to required temperatures…The fifth layer is mostly for margin against imperfections, micrometeoroids, holes, etc,” said James Cooper, James Webb Space Telescope Sunshield Manager at NASA’s Goddard Space Flight Center, Greenbelt, Maryland in a release.
