NASA’s James Webb Telescope is going through some critical manoeuvre phases which will determine its success as a mission to shed light on the origin of the universe. The powerful space observatory, which was launched into orbit on Christmas Day, is heading for a “make or break” moment when it attempts to unpack its five-layered sun shield. The barrier will provide the space telescope with super cold temperatures for its instruments to work properly. And NASA is providing regular updates via Twitter on these tense moments, which are being followed by millions of enthusiasts around the world.

In a tweet, NASA said the James Webb team has successfully extended the Deployable Tower Assembly (DTA) in order to unfold the sun shield in the next few days. The launch of the space telescope from Earth was only the start of a six-month process to get James Webb into place for its job. The process is lengthy, as James Webb Space Telescope is a big observatory, packed into a tiny space inside the nose cone of the Ariane launcher. What this means is that the telescope could only be unfolded once it was released into orbit.

The deployment of DTA creates space between the upper section of the observatory and the spacecraft bus to allow sensitive mirrors and instruments to cool down to necessary temperatures to detect infrared light. This gap will also provide room for the sun shield membranes, each as thin as human hair, to fully unfold.

There’s little room for error.

James Webb Space Telescope “is split into a ‘hot side’ and ‘cold side’ by its sun shield. The sun shield will always be facing the Sun to block out heat and light, as Webb’s mirrors need to stay extremely cold to observe faint heat signals in the universe,” NASA explained in another tweet.

Why the need for this hot and cold separation? Temperatures on the hot side of James Webb will reach as high as 85 degrees Celsius and on the cold side it will be about -233 degrees Celsius. If you are intrigued by such a huge temperature difference, NASA has set up a live tracker. “Note that temperatures will continue to change as Webb unfolds and then cools down to operating temperatures over the next months,” the agency added.

NASA said that the James Webb team has successfully completed two mid-course corrections that will significantly enhance the life of the observatory.

James Webb, meanwhile, has automatically executed the solar array deployment after rocket separation. “Because Webb was already in the correct attitude, the array deployed about 1.5 min after separation, or 29 min. after launch,” the agency added.

The James Webb Space Telescope is a joint project of the NASA, European Space Agency, and the Canadian Space Agency.