The James Webb Space Telescope was transferred to the final assembly building at Europe’s Spaceport in French Guiana on 7 December 2021, to meet its Ariane 5 launch vehicle.

Stowed inside a special 23-tonne transport container, Webb was protected and monitored throughout the transfer.

Ariane 5 was already moved to the same building on 29 November. Here, adjustable platforms allow engineers to access the launch vehicle and its payload.

The next steps are to hoist Webb to the upper platform which has been prepared so that Webb can be integrated on Ariane 5’s upper stage and then encapsulated inside Ariane 5’s specially adapted fairing.

Webb is scheduled for launch on 22 December from Europe’s Spaceport. Ground teams have already successfully completed the delicate operation of loading the spacecraft with the propellant it will use to steer itself while in space.

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).

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