ArianeGroup and SSC Space completed a second wet dress rehearsal of Themis, Europe’s reusable rocket demonstrator, at Esrange in Sweden on 29 September; ESA announced it on 7 October. As in the first rehearsal in July, the tanks were filled with liquid nitrogen chilled to about −200 °C instead of propellant, recreating cryogenic temperatures and pressures without the risks of real fuel. The test also tried out the automated ground systems meant to find the landed vehicle, plug into it and drain leftover propellant while staff stay at a safe distance. The first hop will climb to as high as 100 metres before a vertical landing attempt, funded by the EU’s €42.8 million SALTO project, whose end date was just pushed to 31 December 2026. Our take: steady progress, but Themis still has a full methane-oxygen rehearsal and an engine firing to go before it leaves the ground.
−200 °Cliquid nitrogen in the tanks
100 mfirst hop, maximum height