SIRIUS 1 is Sirius Space Services' flagship dedicated small-satellite launch vehicle, a two-stage rocket powered by the company's in-house methalox STAR-1 engine, designed as the first step toward a fully reusable European launcher family.
SIRIUS 1
SIRIUS 1 is Sirius Space Services' flagship dedicated small-satellite launch vehicle, a two-stage rocket powered by the company's in-house methalox STAR-1 engine, designed as the first step toward a fully reusable European launcher family.
Description
SIRIUS 1 is the flagship launcher of Sirius Space Services (founded 2020, headquartered in the Île-de-France region near Paris, with engine test campaigns conducted at the DLR facility in Lampoldshausen, Germany). It is a two-stage, single-stick orbital rocket standing 34.9 m tall with a 26.6 m central core and a liftoff mass of approximately 180 tons, optimized for small dedicated payloads. It is powered by nine STAR-1 engines on the first stage and one on the second stage; STAR-1 is a reusable liquid methane/liquid oxygen engine producing 55 kN of vacuum thrust per unit and is manufactured in-house using Laser Powder Bed Fusion metal 3D printing. SIRIUS 1 can deliver approximately 300 kg to a 500 km Sun-Synchronous Orbit at 50 degrees inclination. It anchors the broader SIRIUS launcher range (alongside the larger SIRIUS 13 and SIRIUS 15 variants) targeting dedicated launch, rideshare, and secondary payload missions for small satellite operators, with a maiden flight planned for 2027 and a long-term goal of 100% first-stage reusability by 2035.
Specifications
| Payload to SSO 500 km @ 50° | 300 kg |
|---|---|
| Height | 34.9 m |
| Stages | 2 |
| Liftoff mass | 180 tons |
| Engine | STAR-1 (methalox, 9 on stage 1, 1 on stage 2) |
| STAR-1 vacuum thrust | 55 kN per engine |
| Engine manufacturing | 100% in-house, Laser Powder Bed Fusion (L-PBF) |
| Planned maiden flight | 2027 |
| Reusability goal | 100% reusable by 2035, up to 60% launch cost reduction |