James Webb Space Telescope has been fully Deployed in Space

The James Webb Space Telescope has been fully deployed in Space. On January 8, the space telescope successfully deployed its primary mirror. This marked the successful end of all the crucial deployments it was supposed to undertake. 

Figure 1: On January 8, NASA's James Webb Space Telescope has been fully deployed in Space.

Webb Space Telescope is now cruising to its new home; the L2 Lagrange point 1.5 million km away. It is expected to reach there within the next couple of weeks. Webb’s deployment was one of NASA’s most complicated spacecraft activities. It involved the deployment of various components in a sequence. 

The telescope was launched abroad on an Ariane 5 rocket on December 25. It gradually underwent several maneuvers after being released into space. On January 4, Webb complicated the deployment of its 21-meter-sun-shield. With this, 75% of Webb’s single-point-failure items retired. A day later, Webb’s secondary mirror was put into its required position. And now, the team has successfully deployed Webb’s primary mirror as well. Webb has two primary mirror panels on either side. On January 7, the team first deployed the leftmost wing, which took almost 5.5 hours. Then a day later, on January 8, the rightmost wing was also successfully unfurled. 

Figure 2: James Webb Space Telescope's launching launched abroad on an Ariane 5 rocket on December 25.

A telescope’s power depends on how big its primary mirror is. A large primary mirror has more light-gathering capacity to make detailed observations. Considering this, Webb needed a huge primary mirror to achieve its scientific goals. But such a large mirror could not fit inside any existing rockets as one single unit. So the primary mirror was dissociated into 18 segments that could fit inside the rocket. Since hexagonal shape has a six-fold symmetry, it leads to a high filling factor. This further aids the segments to fit together without a gap and effectively create a single unit. Also, 18 hexagonal mirrors make the desired approximately circular shape of the primary mirror. Made up of beryllium and coated in gold, they can look 13.5 billion years back in time. However, they have to align themselves to attain a sharp focus to image the cosmos. After primary mirror deployment, the next task is to align and focus the mirrors. Six actuators attached to each mirror piece’s back will move the segments. They are designed to make adjustments without disturbing the other segments. 

Figure 3: Webb's deployment graphic

The alignment and optimization will take around six months to get completed. In these six months, Webb will cool down and calibrate its instruments. Although it will take some pictures for calibration and optimization, NASA expects Webb to send its first proper science images this summer. 

On the 29th day after its launch, Webb will fire its thrusters for L2 insertion. This is the last crucial step that must be completed to place Webb in its orbit. If the thrusters are not fired properly, Webb will miss the orbital insertion. And if the L2 orbital insertion is missed, the telescope will go on forever into the cosmos. The mirror deployment has marked a successful firing of all 178 release mechanisms. 

Figure 4: Webb's orbit at the L2 point.

Let’s hope that the L2 orbit insertion goes according to the plan. Wishing Webb Space Telescope clear skies and wide eyes!

If you want to learn more about James Webb, click on the link.

MUINUDDIN BASHAR ARONNO was born in Dhaka, Bangladesh. Currently, he is pursuing his B.Eng. degree in Electronics and Information Engineering from Nanjing University of Information Science and Technology, Nanjing, China. He loves working at the intersection of technology, business, and education. 

Follow on: Facebook, Instagram, YouTube