JWST

The James Webb Space Telescope (JWST) is a space-based infrared observatory developed through a collaboration among NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). It is designed to study the formation of stars and galaxies, the evolution of the universe, and the atmospheres of exoplanets by observing infrared light emitted by distant objects and dust-enshrouded regions.

JWST launched on December 25, 2021, from Kourou aboard an Ariane 5 rocket and operates at the Sun-Earth L2 point in a large halo orbit about 1.5 million kilometers from Earth. Its 6.5-meter primary mirror, composed of 18 hexagonal beryllium segments with a gold coating, collects faint infrared signals. A five-layer sunshield keeps the telescope extremely cold to enable infrared observations.

The observatory carries four main science instruments: NIRCam (near-infrared camera), NIRSpec (near-infrared spectrograph), NIRISS (near-infrared imager and slitless spectrograph), and MIRI (mid-infrared instrument combining an imager and spectrograph). A fine guidance sensor provides precise pointing. JWST covers roughly 0.6 to 28 micrometers, delivering high sensitivity and resolution in the infrared and enabling spectroscopy and imaging of faint targets.

Operations and goals: NASA's Goddard Space Flight Center oversees the project with the Space Telescope Science Institute operating science programs; ESA contributed instruments and the launch vehicle, while CSA supported components. The mission aims include probing the early universe, understanding cosmic evolution, studying star and planet formation, and characterizing exoplanet atmospheres and their chemical compositions.