In a development that sounds like a DIY project gone interstellar, German startup Orbital Matter has successfully 3D printed a half-meter-long rigid beam in the vacuum of space using a custom plastic material. The company’s small satellite, Replicator 2, launched on a SpaceX rideshare mission this summer, carried four of its 3D printers onboard. Each printer extrudes coils of resin cured by ultraviolet light - a process the company likens to cement and water - to create a rigid, cylindrical beam. Executives call it a first for a free-flying spacecraft in orbit, and a step toward building large structures in space.

Why does this matter? Because future spacecraft - especially those envisioned as orbital data centers - will need to be larger to generate more electrical power and radiate more heat into the void. But they still have to squeeze into the tight confines of a rocket’s fairing. If spacecraft can build their own structures in orbit, those power and heat-dissipation headaches become a lot easier to solve. “Replicator 2 is the first proof that we can simply build the array in space, at whatever size the mission demands,” said Jakub Stojek, CEO and co-founder of Orbital Matter. The company is partnering with the European Space Agency and Thales Alenia, a leading European satellite builder, which collaborated on Replicator 2.

Today’s large space structures are essentially origami projects - solar arrays or telescope mirrors are folded up and then deployed on orbit. It’s tricky engineering, which is why the idea of manufacturing and assembling structures in space is appealing. NASA has funded some efforts, notably a mission with Redwire that 3D printed structural beams in a vacuum chamber in 2023 but never got off the ground. Orbital Matter’s achievement, by contrast, actually left the planet.

Two of the company’s printers are designed to deploy a flexible solar array, but an anomaly caused one printer to fail. Still, the successfully created boom deployed the solar array and serves as an important proof of concept. Previous 3D-printing efforts in microgravity were confined to the pressurized environment of the International Space Station. “That’s why we put so many printers on this single satellite. We preferred to learn in orbit and adapt the software as needed rather than waste years testing every possibility on the ground,” Orbital Matter CTO Robert Ihnatisin told TechCrunch.

The boom’s length is limited by the amount of resin onboard, but engineers believe 100-meter booms are feasible. For comparison, SpaceX’s Starlink V2 satellites - among the most powerful mass-produced satellites in orbit - use solar arrays that are 20 meters long. Orbital Matter was co-founded in 2022 by Ihnatisin, who previously worked at 3D-printing company FormLabs, and Stojek, and has raised a $3 million seed round.

Now, Orbital Matter is working on another demonstration mission, scheduled for launch in 2028, that will test a larger version of its printer on a bigger satellite. The company hopes this will deploy a solar array generating 5 kW of power - a “stepping stone” toward larger deployments of 100+ kW per wing by 2030. The company is also collaborating with satellite builders considering incorporating its PADS (printer-assisted deployment system) into their spacecraft to extend solar panels, antennas, or other components. Because why fold when you can print?