The James Webb Space Telescope
August 11, 2022
The James Webb Space Telescope (JWST) is the successor to the Hubble Space Telescope. The telescope's main task is to collect data on the most distant objects in space that could not be reached by the Hubble telescope or ground-based telescopes. The telescope is a joint project of the National Aeronautics and Space Administration (NASA) with the European Space Agency and the Canadian Space Agency. JWST provides vastly improved resolution and sensitivity over Hubble and enables a wide range of research studies in many areas of astronomy and cosmology, including the observation of some of the most distant events and objects in space, such as the formation of the first galaxies. Other goals include understanding star and planet formation and directly imaging exoplanets and novae. JWST's primary mirror, an optical telescope element, consists of 18 hexagonal mirror segments that combine to create a 6.5 m (21 ft 4 in; 260 in) diameter mirror. which is much larger than Hubble's mirror at 2.4 m (7 ft 10 in; 94 in). Unlike Hubble, which observes in the near-ultraviolet, visible, and near-infrared (0.1 to 1 μm) spectral ranges, JWST will observe in the lower frequency range, from long wavelengths of visible light to mid-infrared light (0.6 to 27 μm), which will allow it to observe high-redshift objects that are too old and too distant for Hubble to observe. The telescope must be extremely cold to observe in the infrared without interference, so it will be stationed in space near the L2 Earth-Sun Lagrangian point, and a large sunshield will keep its mirror and instruments below 50 K (−220 °C ; −370 °F).JWST was developed by NASA with significant input from the Canadian Space Agency and the European Space Agency. It is named after James E. Webb, NASA administrator from 1961 to 1968, who played a key role in the Apollo program. Development began in 1996, but the project had numerous delays and cost overruns, and underwent a major redesign in 2005. Assembly of the main mirror segments began at the end of November 2015, and was completed at the beginning of February 2016. The construction of the JWST was completed at the end of 2016.