It’s December 2021 and the final moment in a saga, started in 1996, to build and launch a successor to the Hubble Space Telescope. The James Webb Space Telescope (JWST) is due to be hoisted aloft by an Arian 5 rocket from French Guiana on the 22nd. It will then take some 6 months to deploy before any science can be done.
It is a very complex engineering project and there are a host of things that can go wrong during its deployment, so fingers crossed.
JWST is an infra red telescope covering the wavelengths 0.6 to 28.3 µm, cf the visual range of 0.38 to 0.76 µm. This will enable it to look back to the era of the origin of stars and galaxies.
The main objectives of the JWST mission are:-
1) To investigate the light from the dawn of the universe some 13 billion years ago;
2) To study the formation of the first galaxies;
3) To look for the first generation stars and better understand the formation of stars and their planetary systems;
4) To study planetary systems in the Milky Way and potentially analyse the atmospheres of and look for signs of life from these planets.
In order to protect the instrument from the Sun, earth and moon, to get its operating temperature as low as possible, and increase its sensitivity, it is being placed at the Lagrange L2 position, some 1 million miles away in line with the sun and earth, with a huge parasol to protect it. If anything goes wrong then that is it, it cannot be serviced like the HST was!