Eris by Gilmour Space: Australia’s First Orbital Rocket
Australia has just reached a major milestone in its space history. For the first time, a rocket designed, built, and launched locally attempted to reach space. On July 29, 2025, the company Gilmour Space Technologies tested the Eris launcher, marking a strategic turning point for the nation’s space sovereignty. Although the flight did not result in achieving orbit, the launch represents a significant and symbolic technological advancement.
Technical Description of the Eris Rocket
The Eris Block 1 rocket is a three-stage launcher designed to place payloads of up to 305 kg into low Earth orbit. It stands about 23 meters tall with a primary diameter of 2 meters for the first stage.
The propulsion system is based on an innovative combination:
- Four hybrid Sirius engines (3D-printed solid fuel + liquid hydrogen peroxide) for the first stage.
- One Sirius engine for the second stage.
- One Phoenix liquid-propellant engine for the third stage.
This architecture positions Eris as a new-generation light launcher, focused on modularity and cost reduction. It will compete directly with Rocket Lab’s small Electron launcher and Isar Aerospace’s Spectrum launcher.
Comparison between Spectrum, Eris, and Electron Launchers
| Characteristic | Spectrum (Isar Aerospace) | Eris Block 1 (Gilmour Space) | Electron (Rocket Lab) |
|---|---|---|---|
| Country | Germany | Australia | New Zealand / United States |
| Propulsion type | Liquid (RP-1/LOX) | Hybrid (solid + liquid) | Liquid (RP-1/LOX) |
| LEO capacity | >1,000 kg | ~305 kg | ~300 kg |
| Height | ~27 m | ~23 m | 18 m |
| First flight planned | 2025 | July 2025 (partial test flight successful) | Operational since 2018 |
| Strategic objective | European commercial launches | Australian autonomy, scaling up | Frequent launches and recovery |
TestFlight 1 Details
The inaugural launch took place from the Bowen Orbital Spaceport in Queensland, the first commercially licensed orbital launch pad in Australia.
Liftoff completed, launch tower cleared, stage 1 tested.
Awesome result for a first test launch. pic.twitter.com/EYbNbGDz3l— Gilmour Space (@GilmourSpace) July 30, 2025
- The liftoff was successful, with the engines operating nominally for about 23 seconds
- The rocket ascended vertically for 14 seconds, reaching an estimated altitude before losing thrust and falling back into the designated safe zone.
- No damage or injuries were reported, and the launch facilities remained intact.
Despite the abrupt ending, Gilmour Space engineers described the mission as a partial success, as it validated critical systems and gathered essential data for future flights.
Challenges for the Australian Space Industry
The Eris test positions Australia as a nation capable of designing and launching its own rockets from its territory — a strategic asset in the context of the rapidly expanding global NewSpace sector.
The project also benefits from significant public support:
- AUD 5 million funding from the Industry Growth Program.
- Collaboration with the Australian Space Agency.
The Bowen launch site is set to become an orbital hub for the Asia-Pacific region, further boosting Australia’s appeal in the small satellite launch market.
Next Steps and Future Ambitions
Gilmour Space plans a second attempt within the next 6 to 7 months, using a modified version of the Eris rocket. The goal: reach orbit and demonstrate the launcher’s full operational capability. In the medium term, the company is developing a Block 2 version capable of carrying up to 1 tonne into orbit, targeting the communications, Earth observation, and scientific mission markets.
The launch of Eris is far more than a simple test flight — it marks Australia’s entry into the select group of nations with a national orbital launcher. Thanks to this partial yet promising success, Gilmour Space positions itself as a key player in Oceania’s independent space sector and a serious challenger in the global light launch market.
Source
See the press release published by GILMOUR SPACE on 30/07/2025 here.