The NIRSpec (Near-Infrared Spectrograph) is one of the four scientific instruments flown on the James Webb Space Telescope (JWST).[2] The JWST is the follow-on mission to the Hubble Space Telescope (HST) and is developed to receive more information about the origins of the universe by observing infrared light from the first stars and galaxies. In comparison to HST, its instruments will allow looking further back in time and will study the so-called Dark Ages during which the universe was opaque, about 150 to 800 million years after the Big Bang.