Ethan Stiefel working with dancers from the Royal New Zealand Ballet. (Stephen A’Court)

After six weeks and 9,000 miles on his motorcycle, twisting along the spine of the Rocky Mountains and camping under the stars, former ballet dancer Ethan Stiefel had accomplished two things.

He’d grown a handlebar mustache, and he’d figured out his new ballet.

Sitting in a studio at the Washington Ballet one recent morning, Stiefel, 43, strokes the ends of his tawny facial fringe as he recalls the long, meditative days astride his bike this summer. He’d set off on the cross-country journey soon after getting the call from Julie Kent, the Washington Ballet’s newly arrived artistic director, who offered him his first big commission as a choreographer. The trip was a breather from his teaching duties at American Ballet Theatre, where he’d been a principal dancer for 15 years before retiring from the stage in 2012. Stiefel had also been busy developing his choreographic skills with works for ABT students and the cable ballet drama “Flesh and Bone.”

The solo escape also was a rare chance to take a break from shaving. As a native of the clean-cut world of ballet dancers, Stiefel hadn’t ever grown facial hair.

Most important, the miles of open road and solitude helped him sort out his thoughts about his new ballet, which is scheduled to premiere at the Kennedy Center Opera House in May, as part of the grand finale of Kent’s first season as Washington Ballet director. And she had asked Stiefel to connect his ballet with John F. Kennedy, whose centennial falls that month.

“I was elated and flattered,” Stiefel says. “And, like, ‘Whoa.’ I needed a moment.”

Stiefel isn’t easily rattled. After 15 years as a highly versatile principal dancer, and three as director of the Royal New Zealand Ballet, he’s used to taking risks and learning quickly. But this job is different. The discernment of a close friend — Kent, his former ABT colleague — is riding on it, because this is the first commission of her tenure. And he hadn’t a clue how to bring the slain president into it.

“I needed to do some homework,” he says. So he rang up his brother-in-law (Stiefel’s wife is ABT principal Gillian Murphy) for advice on cracking Kennedy’s biography. His brother-in-law, a U.S. history scholar, suggested he read “An Unfinished Life: John F. Kennedy 1917-1963” by Robert Dallek.

“I put that book in a saddlebag and got on the road,” Stiefel says.

[The Washington Ballet announces the return of live orchestras, for Stiefel’s new ballet, too.]

He read the book in the evenings and spent the days contemplating how to turn the material into dance. He sped through the Midwest, down to New Mexico, up to Montana’s Glacier National Park. He met up with Murphy in Yellowstone. By the time his trek was over, he had his subject: Kennedy’s space initiative. And, having spent so much time cooped up inside a helmet, he had some insight into the astronaut experience.

“What an astronaut goes through is so compelling, and I see a lot of parallels in terms of the drive, the discipline, the passion and the intelligence between dancers and astronauts,” Stiefel says. “And there’s the whole idea of movement — earthbound movement to movement on another planet.”

Pointe shoes are an inspiration. “They’re alien to so many people,” he says with a laugh. He envisions his main astronaut character as a woman, launching into the unknown. He’s excited about the design possibilities. While in Washington he met with astronauts at NASA headquarters.

With his Doc Holliday mustache, and wearing an old-school, button-front wool vest over a T-shirt and jeans, Stiefel looks a little steampunky. Leaning back in his chair, he reaches into one of the pockets of his vest and you half-expect him to draw out a pocket watch. Instead, he holds a tiny comb, made of bison horn, for grooming the mustache.

It takes ramrod confidence — and beautiful bearing — to carry off this mix of eccentricity and elegance. And that’s the chief impression that Stiefel leaves. He may be relatively new to choreography, but he’s put in the R&D, is sure of his abilities and eager to get started.

“I’m no mimic,” he says. “I’d like to think my work has some unique qualities. Ethanesque, so to speak.” He smiles broadly, and the mustache spreads, winglike. Stiefel had the good fortune to work with great choreographers as a dancer — Jerome Robbins, Twyla Tharp, Paul Taylor and others — which he says will inform his work. “But the challenge,” he says, “is to look to myself, and be true to myself, and make something new and fresh and inspiring.”

“Those who become great,” he adds, sounding Kennedyesque, “generally are the ones who ask the most of themselves.”