Launch teams monitoring the countdown to the launch of Arianespace's Ariane 5 rocket carrying NASA's James Webb Space Telescope, in the Jupiter Center at the Guiana Space Center in Kourou, French Guiana, on the 25th December 2021. JWST is an infrared telescope launched on 25th of December 2021. It has a 6.5-metre-diameter mirror, with which it will study the formation of stars and planetary systems, and the history of the universe. By using infrared wavelengths, the JWST will be able to see through much of the dust that obscures visible light. It will also study dark matter, which is thought to form the majority of the matter in the universe.