A bright blue streak shot up through the black Florida sky in late March, reaching more than 83 miles above sea level. The mysterious azure glow came from the methane flame that was powering a rocket—the first launched by Relativity Space, a seven-year-old startup valued at $4.2 billion.

That night, CEO Tim Ellis’s vision—that he could 3D print rockets able to withstand the maximum stress of flight—became real. It “was the most emotional experience I’ve had in my entire life,” he says. “It almost looked like AI-generated art . . . like you’re launching a blue star into space. I ran outside, and you immediately hear it. It sounds like a whip cracking in the air. It just feels very alive.”

It was also a milestone in two significant ways. First, Relativity’s 110-foot-tall Terran 1 was the largest metal object ever 3D printed, and the first 3D printed rocket to enter space. This manner of rocket production can exponentially reduce the complexity of aerospace manufacturing: What today requires thousands of distinct parts can now be printed in significantly fewer pieces, bringing down the cost, points of failure, and production time.

Second, the Terran 1 was the first to be powered by methane. (A Chinese space company reportedly launched a methane-powered rocket last year, but the government did not release photos or videos.) Methane burns cleaner than traditional kerosene, meaning that there’s less oil sludge, so the rockets can be refurbished and reused more quickly. Private space companies often take heat for merely replicating NASA’s achievements from 60 years ago, but Relativity’s manufacturing achievement represents an entirely new model for how almost any piece of large, space-worthy equipment gets built.

Terran 1 did not ultimately make it all the way into orbit; a second-stage engine failed to ignite. But a few weeks after the launch, Ellis decided to channel Relativity’s resources toward the next-generation Terran R rocket, which will be 270 feet tall and compete directly with SpaceX to offer launch capabilities to commercial and government clients. He has already secured $1.8 billion in launch contracts, and the Terran R, expected to launch in 2026, will build on everything Ellis and company learned from building and firing Terran 1. Ellis—a onetime aspiring screenwriting major at USC who switched to aerospace engineering during orientation—has always seen the creative potential in his pursuit of the stars. “Space,” he says, “is a fantastic venue for inspiring people to do really ambitious, important things.”

This story is part of Fast Company’s Most Creative People in Business for 2023. Discover the full list of groundbreakers who’ve achieved something meaningful in the past year.