CALLISTO reusable vertical-landing rocket demonstrator

CALLISTO is a single-stage experimental rocket developed jointly by CNES, DLR and JAXA to demonstrate reusable first-stage operations. A restartable, throttleable hydrogen/oxygen engine provides powered ascent and landing, while aerodynamic control surfaces guide the unpowered return and four deployable legs absorb touchdown loads. JAXA’s published configuration is 13.5 m tall, 1.1 m in diameter and 3,600 kg at liftoff; other project summaries round the height to 13 m. It is intended for a progressive suborbital test and refurbishment campaign at Kourou, rather than operational satellite launches.