NASA unfolds James Webb Telescope's huge mirrors in deployment test
The James Webb Space Telescope has crossed another milestone on the path to its long-awaited launch. NASA engineers have now completed a deployment test, unfurling the telescope’s gigantic mirror into the configuration it will take in space.
Ahead of its launch next year, James Webb is currently in the midst of an exhaustive series of tests to make sure that it will work properly once it gets up there. After all, it’s a bit tricky to send a mechanic 1.5 million km to take a look if something goes wrong.
The latest of these tests focused on making sure the spacecraft’s mirrors unfold in the right way. At an impressive 6.5 m (21.3 ft) wide, Webb has the largest mirror ever launched into space, so to fit in the rocket fairing for launch it needs to tuck its wings in. Only once it’s safely in space will it stretch out to full size.
In early March, NASA conducted a full test of this deployment system. Using the internal electronics system, the two side mirror arrays were unfolded to form the full mirror surface. Of course, here on Earth is a very different environment than in space, so for this test special equipment had to be suspended from the ceiling to support the weight of those wings as they moved. When it’s actually go-time, none of that will be needed, since gravity won’t be a factor.
“Deploying both wings of the telescope while part of the fully assembled observatory is another significant milestone showing Webb will deploy properly in space,” says Lee Feinberg, Webb’s optical telescope element manager. “This is a great achievement and an inspiring image for the entire team.”
While it seems like James Webb’s technical and financial hurdles might be in the past, there’s a new problem that threatens to add yet another delay to the launch: COVID-19. Testing work is currently running on a skeleton crew thanks to the virus. This will continue until sometime in April, when there’s a scheduled test of the Deployable Tower Assembly, the structure that provides support and houses some of the brains of the operation. After that, operations will shut down at the facility, as NASA reassesses the situation.
Hopefully the telescope will still make its 2021 launch date and start examining the mysteries of the very first stars to form, and the origin of life.
A time-lapse of the deployment test can be seen in the video below.