It was a man named Michael Melton, 48, from Las Cruces, New Mexico, who was riding around with his head sticking out of what looked like a great black metal trash can—he had built an uncannily accurate model of the brainwave-operated wheelchair used by Captain Pike in the Star Trek episode “The Menagerie.” “I built it on a mobility scooter,” Melton explained. “It took three months.” Accounting for his commitment level, he said, “Star Trek gives us a positive view of the future, of humanity. It so deeply explores all aspects of what it is to be human.” And he rolled away.

“Wow,” said my daughter. “He’s awesome.”

There are many elements to Star Trek that seem to have made it irresistible to fans for almost 50 years (the pilot aired in 1966), drawing them to the six offshoot series (including The Next Generation and Deep Space Nine) and 12 Hollywood movies (the 13th, Star Trek Beyond, premieres in 2016) in the multi-billion-dollar franchise, which is owned by Viacom. There’s all the neat stuff—the technological gadgets, many of which pre-figured modern-day innovations such as touch screens and Google Glass, as Trekkies are quick to mention. There’s the soaring music and sound effects (the sound of the doors opening on the Enterprise is as indelible in any Trekkie’s mind as his mother’s voice), the iconic characters, the often unintentionally hilarious campiness. But the main thing Trekkies talk about when asked why they love Star Trek so much is the philosophy behind it. At a time when America is still grappling with its ugly legacy of racism, the Star Trek creed seems more relevant than ever.

“It sounds corny, but we believe in Gene Roddenberry’s dream,” said Anthony Kwan, 47, from Gainesville, Florida, who was dressed as a Next Generation admiral; he was referring, of course, to Star Trek’s creator.

“His dream of universal peace and everyone on this planet living in harmony,” concurred his friend, William Blumberg, 51, of Irvine, California, who wore an original series commander’s uniform. They had come together with 40 friends from around the country who knew each other from Star Trek conventions.

“People are still attached to the Confederate flag!” Kwan said, shaking his head. “If they got a little Star Trek in their lives the world would be a better place.”

“It’s about embracing diversity,” Blumberg said.

“There’s nothing wrong with being a Trekkie,” Kwan reassured my daughter. “If anybody tells you being a nerd is out of style, tell them there’s 5,000 of us here! Get over it!”

The men gave a hearty laugh.

My daughter was too awestruck to tell the men that, ever since Zooey Deschanel and Wes Anderson, being a nerd is actually in style these days.

“Trekkies are so great,” she said when they had gone off to join their Starfleet Academy cheerleading team. “It makes me proud to be a Trekkie.”

By Gabe Ginsberg/Getty Images.

Trekkies have been somewhat vindicated in recent years; their devotion can no longer be seen as any more zealous than the fans of such mega-franchises as Twilight and Harry Potter. But once upon a time, before geeks ruled the earth, via Silicon Valley, Trekkies were seen as cultish misfits. “Get a life, will you, people?” William Shatner railed in an infamous skit on Saturday Night Live in 1986. “I mean, for crying out loud, it’s just a TV show. . . . Move out of your parents’ basements and get your own apartments and grow the hell up!”