Gilmour Space launched the first test flight of its homegrown Eris rocket, which aims to become the first sovereign-built vehicle to reach orbit from Australian soil.
After liftoff at 22:35 UTC on July 29, the vehicle slowly cleared the launch tower and drifted to the side before coming back down to Earth. The vehicle cleared the launch tower and flew for around 14 seconds, with an engine burn lasting for 23 seconds.
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 company had previously planned to launch on July 16 but had pushed the attempt back, citing operational delays and unfavorable wind forecasts. A further attempt with a ten-hour launch window on Monday, July 28, was also stood down due to wind limits.
These followed an unexpected delay two months earlier when, on May 16, the vehicle’s fairings were prematurely triggered by the separation system during overnight launch preparations. An unexpected power surge from other devices downstream had caused the vehicle to shut down, resulting in the issue. Replacement fairings were quickly dispatched from the company’s Gold Coast facility, and the team worked to mitigate the problem.
As with the SaxaVord site in the UK, regulatory approvals can be complicated and long-winded, especially for new launch sites. The Gold Coast-based company was granted a provisional launch permit last November and had previously intended to launch in mid-March. The Civil Aviation Safety Authority (CASA) had approved the company’s maiden flight in late April, and the Australian Space Agency gave the final sign-off on May 13.
The Bowen Orbital Spaceport is Australia’s first licensed commercial orbital launch facility. (Credit: Gilmour Space)
This was the first orbital launch permit issued by the space agency. Preparations to launch in May were then delayed by Tropical Cyclone Alfred, which had moved into the area, and this latest attempt is also subject to favorable weather conditions.
The company’s Bowen Orbital Spaceport is situated at Abbot Point, north of the coastal town of Bowen in North Queensland, Australia. The picturesque site affords 20 to 65-degree, low to mid-inclination equatorial orbits. The spaceport was developed in agreement with the Juru traditional custodians of the land in late 2021 and officially opened last April.
Proudly bearing the “Australian-made” emblem on its upper stages, Eris is a three-stage rocket. Comparable to Rocket Lab’s Electron, it stands a little taller than Electron at 25 m in height. The vehicle also has a slightly larger 1.5 m fairing and boasts a payload mass of up to 215 kg to a 500 km Sun-synchronous orbit, or 305 kg to 500 km equatorial orbits.
Sirius hybrid engine qualification testing. (Credit: Gilmour Space)
The first stage is propelled by four Sirius engines — a proprietary hybrid engine that uses a 3D-printed solid fuel grain and a Hydrogen Peroxide liquid oxidizer. The additive manufacturing approach allows for complex geometries within the grain, designed to optimize the fuel’s burn characteristics and improve engine performance.
Another single Sirius engine powers the second stage, while the third uses a Phoenix engine, which burns liquid propellants. A successful orbital launch would also be the first for a hybrid rocket design.
Both the vehicles and their engines are manufactured in-house, with expanded use of 3D printing. Gilmour Space selected EOS as its additive manufacturing partner in late 2023 as it transitioned beyond the prototyping stage.
‘TestFlight 1’ was the first orbital launch attempt from Australian soil in over 50 years. The flight path was on a northeasterly trajectory over the Coral Sea.
Eris lifts off the pad on its maiden launch attempt (Credit: Gilmour Space)
To date, only two successful orbital launches have been conducted from Australia, the first of which took flight from the Woomera Test Range in South Australia in November 1967, when the nation’s first satellite was lofted atop a modified Redstone rocket.
The launch of the Weapons Research Establishment Satellite (WRESAT) mission established Australia as the third country to launch a satellite into orbit from its own territory, following the Soviet Union and the United States. The United Kingdom’s Black Arrow then successfully launched the Prospero satellite into orbit from Woomera four years later in October 1971.
Since then, Australia has launched hundreds of suborbital missions, including sounding rockets for NASA missions from the Arnhem Space Centre in the Northern Territory and many others from the Whalers Way Orbital Launch Complex and Koonibba Test Range. The latter supported the launch of German company HyImpulse’s SR75 last May — another vehicle that utilizes hybrid propulsion and proprietary fuel grains.
Eris is transported horizontally at Bowen Orbital Spaceport. (Credit: Gilmour Space)
Gilmour Space also builds its own satellites, and the company’s 100 kg modular ElaraSat bus is capable of delivering 72U of payload to orbit. The bus was selected by Perth-based LatConnect60 for a forthcoming demonstration mission that will use the short-wave infrared range to provide insights into methane and carbon emissions from space. This particular prototype satellite will be integrated in Gilmour Space’s Queensland facility, but then launched by Skyroot Aerospace in India.
Gilmour Space’s first suborbital launch of the RASTA Mk2 occurred nine years ago in July 2016. The flight demonstrated the company’s hybrid engine technology for the first time and was notable for being among the first of its kind to use a 3D-printed fuel grain.
The company is now offering its commercial and defense customers a suborbital test flight service, which will deliver payloads at hypersonic speeds in excess of Mach 5 — more than five times the speed of sound. This HyPeRsonic FLight Test (HPRFLT) service addresses the growing demand for the prototyping and testing of high-speed vehicles and materials, going beyond what ground-based tunnel testing and simulations can provide.
Render of Eris in Block 1 configuration?(Credit: Gilmour Space)
A second Eris vehicle is already being built, incorporating some design improvements that could be further refined based on data from the maiden flight. Further along the roadmap, Gilmour Space is planning for a Block 2 version of the vehicle that will feature higher performance, making Eris more akin to Firefly Aerospace’s Alpha vehicle. This version will deliver up to 1,000 kg to LEO and will be used for the company’s Caravan-1 rideshare mission. A medium-lift Eris Heavy is also planned, capable of lofting up to 4,000 kg to LEO and potentially even crew capsules.
Gilmour Space has several commercial agreements in place for future missions with operators of orbital transfer vehicles (OTV). The company signed its first European partnership agreement with rideshare specialist Exolaunch almost four years ago, which would give it access to low-inclination missions and unique orbits. The company also signed a memorandum of understanding (MOU) in February 2023 with Atomos Space. Through this MOU, Atomos will contract launch services aboard Eris. At the same time, the vehicle will also carry Atomos’ OTVs in the future, offering customers additional in-space transportation and orbit-raising services.
View of the Eris rocket on the pad at the spaceport in Bowen, Australia. (Credit: Gilmour Space)
Australia’s Department of Defence also contracted with Gilmour Space in 2022 to develop and launch a new G-class sovereign surveillance satellite — part of the government’s increased investment in space capabilities. A future all-Australian mission will additionally send two Mayla thermal infrared cameras to orbit. These were developed by Australian Astronomical Optics (AAO) at Macquarie University. Rather than develop space-grade cameras from scratch, the team has successfully modified an off-the-shelf camera for use in space. Potential applications of this space-based heat-detecting technology include the detection of bushfires.
On July 25, the Australian Space Agency announced that Gilmour Space had received an AUD $5 million funding boost from the Australian Government, ahead of the vehicle’s maiden launch. The government’s Industry Growth Program helps small Australian companies to grow their business and is intended to accelerate the development of the Eris rocket.
New Zealand-based Frond Space Systems is supplying a lightweight and compact MICRO dragsail for Gilmour Space’s forthcoming MMS-1 satellite mission. This dragsail will be attached to a 100 kg microsatellite and will activate at the end of its five-year operational lifespan, accelerating its deorbit as part of the company’s commitment to the sustainable utilization of space.
Eris stands vertical against a scenic sky (Credit: Gilmour Space)
As with many new launch vehicles, the path to Eris’s debut launch has been longer than initially projected. The inaugural Eris rocket was fully integrated and moved into its vertical launch position in April 2024, and had completed its dress rehearsals before the end of that year. Eris had spent much of the time since then resting horizontally inside the Bowen spaceport’s Vehicle Assembly Building.
There was no official livestream for the maiden flight, but the company has since released video and images. For this launch, the company preferred to “limit non-essential network traffic to minimise operational risk”, according to its social media posts. As with SaxaVord’s spaceport, there are no immediate plans for on-site launch viewing. However, this will inevitably follow once the site has supported several launches, bringing an additional boost to the local economy.
(Lead image: Eris launches from Bowen Orbital Spaceport. Credit: Gilmour Space)
