James Webb was to be sent into space about 20 years ago. A lot of technological advances and even new inventions were needed to complete this telescope. The project faced many challenges and got delayed. Now it is ready and the wait was not in vain. It is set to launch on December 28 this year. This telescope could completely change our understanding of the universe. This telescope will be the first that will be able to see distant galaxies and give a glimpse of what the universe looked like 250 to 100 million years before the Big Bang.
The Hubble telescope was like our window into space. Through it we saw how incredibly vast, dazzling, and at times strange and scary the universe can be. We got shocking color photos of galaxies and gas clouds of different types and sizes. Hubble gave us a better idea of the age of the universe, about 13.8 billion years. It was only through Hubble that it was confirmed that the universe is expanding at an accelerated rate, which many scientists did not believe before.
If we achieve this through Hubble, then we can see and learn so many wonderful new things through the new James Webb telescope, the largest and most complex and most detailed ever. This telescope has the largest primary mirror ever known in space. There are 18 gold-studded hexagonal small mirrors, and they are more than six times the size of Hubble. This telescope will be the first which will be able to see distant galaxies and will be able to show a glimpse of what the universe looked like 250 to 100 million years before the Big Bang, that is, we will get not only the first baby pictures of the universe but possibly the first galaxies.
The giant size of this telescope is a big challenge. Sending a six-and-a-half meter (21 ft) wide mirror into space is not an easy task. The rocket carrying it, Ariane-5, is unable to carry anything more than five meters wide. For this reason, the telescope is designed in such a way that it can be folded and fitted in the rocket. Second, the telescope can only operate at near-absolute temperatures (-223 °C), so it needs a five-layer shield the size of a tennis court to protect it from the sun. Going into space, the telescope will start opening in its complex and beautiful posture. It will take three weeks to fully open. The final destination of the telescope is 1.5 million kilometers from Earth.