10.01.2026

Credit: ArianeGroup / Swedish Space Corporation

The European Space Agency (ESA) has revealed that, with the launch facility in Sweden currently “under snow,” it is “waiting for spring” to launch an initial hop test of its Themis reusable rocket booster demonstrator.

ESA began work on the Themis project in 2019 as a means of maturing reusable rocket technology for future European launch systems. In June 2025, the first Themis demonstrator was transported by ArianeGroup, the project’s prime contractor, from its facility in Les Mureaux to the Esrange Space Centre in northern Sweden. In September, ArianeGroup announced that the 28-metre-tall demonstrator has been transferred to the launch pad ahead of a combined test campaign that would represent the final step before an initial low-altitude hop test. Since then, however, there have been no further updates on the progress toward that first flight.

On 8 January, during a press conference following Director General Josef Aschbacher’s annual briefing, Toni Tolker-Nielsen, acting Director of ESA’s Space Transportation programme, was asked about the status of the initial test flight of Themis. In response, Tolker-Nielsen explained that the weather had been the determining factor.

“It’s in Kiruna and it’s under snow today,” he explained. “So we are waiting for spring.”

In his initial remarks, Director General Aschbacher revealed that the agency was currently targeting the first quarter of 2026 for the first hop test of Themis.

While testing in Sweden was initially expected to be limited to low-altitude hop tests, in November 2024, ESA awarded ArianeGroup an additional €230 million to expand the scope of testing at the Esrange Space Centre. In addition to an evolution of the Prometheus rocket engine that powers Themis, the funding was to be used for an upgraded variant of the single-engine version of the demonstrator, called the T1E, which would be used for medium-altitude hop tests.

Once testing in Kiruna is complete, testing of a more powerful three-engine variant of the booster demonstrator, known as T3, is expected to begin at the Guiana Space Centre in French Guiana. This phase is intended to include higher-altitude hop tests and to significantly expand the vehicle’s flight envelope.

Quelle: European Spaceflight LTD