The upper stage of Ariane 5 which will transport the James Webb Space Telescope in space, is now integrated with the Ariane 5 core stage inside the launch vehicle integration building at Europe’s Spaceport in French Guiana.

The upper stage arrived at the launch vehicle integration building on 11 November 2021 where it joined the Ariane 5 core stage and boosters. It was then hoisted high to awaiting engineers so that it could be integrated on top of the core stage.

The Ariane 5 upper stage is powered by the HM7B engine. It will contain 14.7 t of liquid oxygen and liquid hydrogen propellant to deliver 6.6 t of thrust for 1000 seconds. After core stage separation, the upper stage will provide attitude control during the ascent and separation of Webb on its path to the Lagrange point.

The Vehicle Equipment Bay, ‘the brain’ of Ariane 5, which is integrated with the upper stage, autonomously controls the whole vehicle and transmits all key flight parameters to the ground station network.

Webb will be the largest, most powerful telescope ever launched into space. As part of an international collaboration agreement, ESA is providing the telescope’s launch service using the Ariane 5 launch vehicle. Working with partners, ESA was responsible for the development and qualification of Ariane 5 adaptations for the Webb mission and for the procurement of the launch service by Arianespace.

Webb is an international partnership between NASA, ESA and the Canadian Space Agency (CSA).

These activities mark the beginning of a five-week campaign to prepare the Ariane 5 launch vehicle which runs in parallel with teams preparing Webb, which started three weeks earlier. Soon Webb will meet Ariane 5 and teams will unite for the final integration for launch.

Find out more about Webb in ESA’s launch kit.