James Webb Space Telescope - Overview

Overview

JWST originated as the Next Generation Space Telescope (NGST) in 1996, based on generic planning for Hubble successor at least as early as 1993. It was renamed in 2002 after NASA's second administrator (1961–1968) James E. Webb (1906–1992), noted for playing a role in the Apollo program and establishing scientific research as a core NASA activity.

The telescope is a project of the National Aeronautics and Space Administration, the United States space agency, with international collaboration from the European Space Agency and the Canadian Space Agency, including contributions from fifteen nations.

Europe's contributions were formalized in 2007 with an ESA-NASA Memorandum of Understanding, that includes the Ariane-5 ECA launcher, NIRSpec instrument, MIRI Optical Bench Assembly, and manpower support for operations.

The JWST will orbit the Sun approximately 1,500,000 kilometres (930,000 mi) beyond the Earth, around the Earth-Sun L2 Lagrange point (L2 halo orbit). Objects near this point can orbit the Sun in synchrony with the Earth, which allows the JWST to use one radiation shield, positioned between the telescope and the Sun, to protect it from the Sun's heat and light and a small amount of additional infrared from the Earth. The telescope will be in a very large 800,000 kilometres (500,000 mi) radius halo orbit around L2, and so will avoid any part of Earth's shadow. From the JWST's position, the Earth will be very close to the Sun's position but not eclipse it, while the Moon will show a tiny crescent phase during its maximum angular distance from the Sun.

The telescope is planned for launch on an Ariane 5 rocket on a five-year mission (10-year goal) with a planned launch date in 2018.