The first model of the European Space Agency’s (ESA) reusable rocket demonstrator Themis has reached an important milestone at the Esrange Space Center in Kiruna, Sweden. The T1H vehicle (Themis-1) now stands vertically on its four landing legs, fully assembled on its launch pad.
This marks the first time the Themis stage demonstrator has been fitted with its legs, completing its integration ahead of the next major phase of testing. Themis is designed to demonstrate key technologies for rocket stage recovery and reuse in Europe.
The Themis demonstrator is powered by Prometheus®, a new-generation reusable engine that uses cryogenic propulsion. Prometheus® can be restarted in flight and its thrust throttled to enable a soft and controlled landing—making Themis the first full-scale European vertical take-off and landing rocket element to employ such technology.
After being transported over 3,000 kilometers from ArianeGroup’s integration facility in Les Mureaux, France, to Esrange Space Center in Kiruna, Sweden, the rocket underwent final assembly and preparation. The verticalisation and leg installation mark a major step forward in the path toward flight.
With Themis now installed on the launch pad, the project enters its “combined tests” phase, during which interfaces between the rocket and the ground systems will be verified. These tests will culminate in a wet dress rehearsal under cryogenic conditions, followed by a low-altitude “hop test” that includes lift-off and landing.
Developed under ESA’s Future Space Transportation Preparation Programme, Themis is led by ArianeGroup as prime contractor with the support of multiple European industrial partners. Its upcoming test campaign will be conducted within the framework of the SALTO (Reusable Launchers Technologies) project, funded by the European Union’s Horizon Europe Space Research and Innovation Programme.
The Themis project represents a major step toward Europe’s ambition to develop reusable launch vehicles, strengthening autonomy and sustainability in future space transportation systems.