Reaction Dynamics (RDX) was in Sydney, Australia for the International Astronautical Congress conference, and announced a MOU with Australia’s Space Machines Company for responsive space operations.
The two companies will work together on rapid-response constellation upkeep and maintenance, which pairs together RDX’s Aurora hybrid propulsion launch vehicles with Space Machines’ Optimus Viper maintenance spacecraft. The goal, according to their announcement, is “combining on-demand launch with in-orbit inspection and servicing”.
SpaceQ exchanged email with Jesse Mikelberg, head of Business Development and Strategic Partnerships, RDX about the MOU.
RDX and responsive launch
RDX is currently developing the Aurora launch vehicle, which uses a mix of a liquid oxidizer and a solid fuel in what’s known as a “hybrid” propulsion system. In the past, technical issues have meant that hybrid engines weren’t seen as viable for launchers, but RDX has developed a novel (and proprietary) fuel design that’s engineered to burn consistently and cleanly, while being simultaneously non-toxic and environmentally friendly.
One aspect of that approach is that the fuel is shelf-stable over long periods of time, with low-to-minimal risk of combustion. Combined with the “drastically simplified propulsion architecture” of RDX’s RE-101 and RE-102 engines compared to other rockets, it opens up the possibility of Auroras being stored for long periods of time and then quickly fueled up and launched, which is impractical-to-impossible for a traditional liquid-fueled rocket.
Over the past year, and including on their successful bid for a million-dollar investment on Meet the Drapers, RDX has emphasized this as a potential advantage for both sovereign and commercial launch customers. Customers could buy launchers and this solid fuel and store them for long periods of time, before being able to quickly launch them into whichever orbit they’re needed.
Space Machines and rapid response
This is where the Space Machines Company MOU fits in. Mikelberg explained that the deal “sets out a framework for joint technical exchanges, coordinated planning, and cooperative outreach between Reaction Dynamics and Space Machines Company.”
Space Machines is focused on on-orbit maintenance, and is developing the Optimus Viper Rapid Response Vehicle, its Scintilla engine, and its AI-driven Solstice OS. The Viper can close in on target satellites, diagnose issues, and potentially deploy one of several payloads to perform on-orbit repairs, avoiding the (potentially expensive) cost of launching whole new satellites into a communications or earth observation constellation.
A company facing a challenging situation with a key satellite might need to get a maintenance vehicle like the Viper into the area as soon as possible. They could end up waiting for weeks or months for a spot on a SpaceX launch, however, and then wait even longer to get the Viper into the right intercept orbit.
By using an RDX Aurora, though, the whole process becomes far simpler, and Mikelberg said that “it quickly became clear that our technologies and philosophies are highly complimentary.”
Since an Aurora can be stored over the long term and fueled up relatively quickly, operators can rapidly have an Aurora deliver one of Space Machines’ Optimus Vipers (or another maintenance craft) into the area, ready to provide near-immediate servicing.
The RDX announcement said that “satellites can be inspected, verified, and supported within days — accelerating time to revenue, lowering constellation maintenance costs, and proving compliance with hashtag#sustainability commitments.”
Mikelberg said that RDX “see[s] a future where operators and allies can deploy or replace satellites from sovereign territory, on-demand, not months or years later”, and that that the partnership combines “fast access to orbit with in-orbit flexibility to make space infrastructure more adaptive and resilient.”
According to Mikelberg, the goal is “enabling true end-to-end responsiveness for satellite constellations, from deployment to replenishment, inspection, and lifecycle management.”
Upcoming suborbital test
The announcement at IAC 2025 was attended by CSA President Lisa Campbell and Enrico Palermo, head of the Australian Space Agency.
Rajat Kulshrestha, CEO of Space Machines Company, said that “linking Canadian launch services with Australian orbital servicing” helps to demonstrate “how allied nations can deliver resilient, sovereign space infrastructure.”
Bachar Elzein, CEO of Reaction Dynamics, said that “[t]his is about more than just launch or inspection — it’s about building the foundation of a truly responsive space economy.”
The team has returned to Canada, but will be returning to Australia for their first suborbital test of the Aurora. Mikelberg said that the team will be “heading back to Australia shortly, along with our flight-ready vehicle, as preparations ramp up for the upcoming mission and demonstration.” The suborbital flight is scheduled to take place in Q2 of 2026, from the Kooniba Test Range in South Australia.
After that, Mikelberg said, “our orbital demonstrations are planned for 2028 from Spaceport Nova Scotia via [a] dedicated launch pad.” The company recently took a stake in Maritime Launch Services, the owners and future operators of the Spaceport, valued at $1.7M.