Exposure: James Webb space telescope

Dwarfing Nasa technicians as a giant crane moves it to a spotless clean room, this is the new James Webb space telescope.

It will be the most powerful space telescope ever built. The scientific successor to the Hubble telescope, it will be launched on board an Ariane 5 rocket from French Guiana in October 2018. The massive science and engineering project began more than 20 years ago and is set to cost almost $9 billion. 

The James Webb telescope is being built in an international collaboration between Nasa, the European Space Agency and the Canadian Space Agency. Its ultra-lightweight beryllium mirror is more sensitive and six times bigger than Hubble’s, and it will operate further away from Earth to maintain an extremely cold working temperature. 

The mirror is coated with 48.25g of gold – about the same weight as a golf ball. The metal was picked because it reflects red radiation well, including infrared light. The satellite will detect infrared rays from the first galaxies that ever formed in the universe, effectively looking back in time, and will peer inside dust clouds where stars and planets are forming today.