JWST
Space probe
Facts
- Launch
- 25 December 2021
- Primary mirror
- 6.5 m, 18 hexagonal beryllium segments
- Sunshield
- 5 layers of Kapton, the size of a tennis court
- First science images
- July 2022
The James Webb Space Telescope is the largest, most powerful and most complex telescope ever launched into space: a joint mission of NASA, ESA and CSA that orbits the Sun at the L2 point, 1.5 million km from Earth.
Its mirror is coated with a layer of gold 100 nanometres thick, which reflects infrared light better. The sunshield cuts the Sun's heat by more than a million times, and the MIRI instrument works at 7 kelvin, chilled by a cryocooler.
It is named after James E. Webb, who led NASA from February 1961 to October 1968, in the years of the Apollo programme.