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About Webb's Launch

image of the earth showing French Guiana

The Webb will be launched from Arianespace's ELA-3 launch complex at European Spaceport located near Kourou, French Guiana.

The Launch Segment has 3 primary components:

1. Launch Vehicle: an Ariane 5 ECA with the cryogenic upper stage. It will be provided in the single launch configuration, with a long payload fairing providing a maximum 4.57 meter static diameter and useable length of 16.19 meters.

2. Payload Adapter, comprising the Cone 3936 plus ACU 2624 lower cylinder and clamp-band, which provides the separating mechanical and electrical interface between the Webb Observatory and the Launch Vehicle.

3. Launch campaign preparation and launch campaign.

The European Space Agency (ESA) will provide the launch vehicle and the payload adapter to the Webb Mission. The launch campaign preparation and launch campaign is the mutual responsibility of NASA, ESA, NGAS, and Arianespace.

Ariane 5 Ariane 5 Ariane 5 Ariane 5
Credit: Arianespace - ESA - NASA

Watch an Ariane 5 rocket launch!

Download a .mov file (right-click and save)


Additional information on the Ariane 5 can be obtained at:

Additional information on the launch site can be obtained at:

launch site