Themis flight model main engine bay during assembly

Reuseable rocket stage demonstrator Themis during assembly at ArianeGroup site in Vernon, France, October 2024.

Themis comes in at 28 m tall, and its Prometheus engine is almost as powerful as the Ariane 6 Vulcain 2.1 engine. Themis encompasses all the elements for a reusable rocket stage. The Themis programme includes developing the flight test model shown here that requires new technologies from European countries such as the vehicle landing legs, grid-fin aerodynamic stabilisers, light-weight fuel tanks, distributed power systems, avionics and reduced-diameter multi-engine bay.  New flight algorithms, derived from previous European projects, will be key to make Themis land safely after flight.

Having finished its testing programme on the main systems at ArianeGroup’s nearby Vernon test facility in France, the reuseable rocket stage is now being built up with all the components necessary to launch, land vertically, and be reused for another mission.