James Webb Space Telescope
The James Webb Space Telescope
(JWST) is a planned orbital infrared
observatory, intended (in part) to replace the aging Hubble Space Telescope
. Formerly called the Next Generation Space Telescope
(NGST), it was renamed after NASA
's second administrator, James E. Webb, in 2002
. The telescope's launch is planned for sometime between 2009
. Its orbit (at the L2 lagrangian point
point, around 1.5 million km from Earth) is considerably beyond the maximum altitude achievable using the Space Shuttle
, so JWST will probably be placed in orbit using a European Ariane 5
launcher. This height also means that, unlike Hubble, it will not be possible to repair or upgrade the observatory during its 5-10 year design life.
Although JWST has a planned weight half that of the Hubble, its primary mirror (a 6.5 meter segmented beryllium reflector) is more than 5 times larger.