section_path: Future of space exploration/James Webb Space Telescope
section_name: James Webb Space Telescope
paragraph_text: James Webb Space Telescope
  
  The James Webb Space Telescope (JWST or "Webb") is a space telescope that is the successor to the Hubble Space Telescope. The JWST will provide greatly improved resolution and sensitivity over the Hubble, and will enable a broad range of investigations across the fields of astronomy and cosmology, including observing some of the most distant events and objects in the universe, such as the formation of the first galaxies. Other goals include understanding the formation of stars and planets, and direct imaging of exoplanets and novas.
  
  The primary mirror of the James Webb Space Telescope, the Optical Telescope Element, is composed of 18 hexagonal mirror segments made of gold -plated beryllium which combine to create a 6.5-meter (21 ft; 260 in) diameter mirror that is much larger than the Hubble's 2.4-meter (7.9 ft; 94 in) mirror. Unlike the Hubble, which observes in the near ultraviolet, visible, and near infrared (0.1 to 1 μm) spectra, the JWST will observe in a lower frequency range, from long-wavelength visible light through mid-infrared (0.6 to 27 μm), which will allow it to observe high redshift objects that are too old and too distant for the Hubble to observe. The telescope must be kept very cold in order to observe in the infrared without interference, so it will be deployed in space near the Earth–Sun L Lagrangian point, and a large sunshield made of silicon - and aluminum -coated Kapton will keep its mirror and instruments below 50 K (−220 °C; −370 °F).