An almost entirely 3D-printed rocket is ready to blast off from Cape Canaveral, Florida, then head for low Earth orbit.
Scheduled for a three-hour launch window that opens at 1 pm Eastern time tomorrow, the inaugural launch of Relativity Space’s Terran 1 rocket will constitute a major milestone for the California-based startup, and for expanding the use of 3D printing in the space industry. Relativity and similar companies envision ultimately using the technology to construct tools, spacecraft, and infrastructure while in orbit, on the moon, or on Mars—in those cases, utilizing lunar and Martian dirt for building materials.
But first, company engineers want to see how Terran 1 fares on this crucial test flight, an event the company has dubbed “Good Luck, Have Fun.” “The number one goal for our rocket is to collect as much data as possible and learn as much as possible from the flight,” says senior vice president Josh Brost. He and his colleagues will be closely watching its path through the stratosphere as it reaches a trajectory point called “max q” about a minute after launch, when intense dynamic pressure will put stresses on rocket. Terran 1 is fueled by liquid oxygen and liquid natural gas, and “in history, no brand-new company has had their first liquid-fueled rocket make it all the way into space on its first attempt,” Brost says. “It’s incredibly challenging.”
Despite its unconventional assembly process, the Terran 1 launch vehicle looks like any other: The two-stage rocket stands 110 feet tall and is 7.5 feet in diameter. Eighty five percent of the rocket by mass, including its major structures, were 3D-printed—only the computing system, electronics, and readily available parts like fasteners were not. (The company is shooting for 95 percent for future rockets.) Other companies have used 3D-printed parts before, but this is on another level: Relativity Space refers to Terran 1 as the world’s largest 3D-printed object.
To create the rocket stages and components, the company designed its own massive 3D printers, the biggest of which they called Stargate. The process uses a robotic arm with a printhead that extrudes an aluminum alloy. Brost says the company’s next generation of 3D printers will be even larger, able to print a single element that’s 24 feet in diameter and 120 feet long.
Printing most of a rocket offers many advantages, Brost argues. Once the printer’s ready, the company can build many large, complex parts and consolidate them into one, like a big set of Lego blocks. That reduces labor costs and makes the supply chain easier to manage, he says, and will ultimately result in less expensive space hardware.
Relativity Space wants to use Terran 1 to (comparatively) cheaply lift satellites for other companies and NASA into Earth orbit. It also plans to construct Terran R, a larger, more powerful, fully reusable rocket that the company hopes will compete with SpaceX’s Falcon 9which has a smaller payload capacity and only reuses the rocket’s first stage. In late 2024, Relativity plans to test using Terran R to launch payloads to Mars; another startup, Impulse Space, will provide the lander.