Following the triumphant deployment and "tension" earlier this week of the 5-layer sunshade for the James Webb Space Telescope, the long-awaited successor to Hubble and a major step forward for astronomy, NASA announced Wednesday that the Secondary mirror has also been successfully extended.
Like a divine latch, @NASAWebb's secondary mirror is now fully deployed and locked! The team remains focused as they work towards this week's final essential milestone: the deployment of the iconic honeycomb mirror. Details: https://t.co/xSRXwCNd8V #UnfoldTheUniverse pic.twitter.com/dAkMNApb2F January 2022, XNUMX
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The extension of the arm to unfold the telescope's secondary mirror was one of the main anxiety points of the mission; if something mechanically failed during this process, it would have been unrecoverable and the telescope would not work.
Fortunately, everything went perfectly, and we just have to await the expansion of its now-iconic honeycomb primary mirror later this week, which is going to be the critical next step for the telescope's deployment.
Analysis: This was arguably the most essential deployment of the entire mission.
What makes the secondary mirror so essential? It is one of the few parts of the telescope that simply could not stop deploying if the mission were barely successful.
If the deployment of the sunshade failed, Webb would not be able to capture the deep infrared light for which it was developed, but it would still be able to capture the near infrared. It would be an improvement over the Hubble Space Telescope, but not as much as we hope.
If the primary mirror is not successfully deployed by the end of this week, the telescope will lose sensitivity, but it will still be able to run and deliver new deep infrared images, but not as well as we would like.
However, without the secondary mirror, no light would reach the telescope's infrared sensors, thus immediately failing the mission. No light, no telescope.
So it was absolutely essential that the secondary mirror unfold properly, as it has now.
"We're six hundred miles from Earth and we have a telescope," Bill Ochs, Webb's program manager, told his team once the mirror was successfully extended and locked securely in place.
At a minimum, the James Webb Space Telescope should now be running to a certain point. The moment the primordial mirror unfolds, we will know how close we are to marching with perfection. Fingers crossed!