Overview

• The first Themis model, T1H, is upright at Esrange in Kiruna with its four landing legs installed for the first time, completing full assembly.
• Standing 30 meters tall and 3.5 meters wide, the demonstrator is built for low‑altitude takeoff and landing tests using cryogenic propulsion.
• Powered by the Prometheus engine, the vehicle features in‑flight restart and throttling for controlled landings, with performance near Ariane 6’s main engine.
• ArianeGroup says integration kicks off “combined tests” to exercise mechanical, electrical and fluid interfaces with the pad, aiming for a cryogenic-conditions test.
• Wet dress rehearsals and the initial hop campaign are being conducted under the EU‑funded Horizon Europe Salto project, which involves 25 partners from 12 countries, with reporting indicating hops could start late 2025 or early 2026.