Artist's rendering of the JWST observatory. Credit: NASA Looking back in time NASA’s James Webb Space Telescope (JWST) will look further back in time than any other telescope - to 400m years after the Big Bang. JWST is a collaboration between ESA, NASA and the Canadian Space Agency, due for launch in late 2021 as the replacement for the Hubble Space Telescope. The four key goals of the JWST are: to search for light from the first stars and galaxies that formed in the Universe after the Big Bang to study the formation and evolution of galaxies to understand the formation of stars and planetary systems