Everybody knows the name of the first man to step foot on the moon, but how many have heard the story of the kid who walked there before him? Richard Linklater’s “Apollo 10 1/2: A Space Age Childhood” reflects one of the director’s childhood fantasies, informed by growing up in South Texas, a stone’s throw from Johnson Space Center, at the time NASA was trying to do the impossible. “Houston, we have a problem,” he playfully imagines the organization’s top scientists saying, “We accidentally built a lunar module a little too small.” Ergo, they need a 10 1/2-year-old to go up in Neil Armstrong’s place.

As someone slightly younger than Linklater who also spent his formative years in Texas, it’s impossible to overstate how much I adore that premise and the collection of associations it brings up for the “Boyhood” director. Significantly advancing the rotoscope animation style he used in “Waking Life” and “A Scanner Darkly” two decades earlier, Linklater spends most of this winsome film’s running time reminiscing about what life was like in 1969, back when the U.S. was neck-and-neck with the Soviet Union in the space race, and kids rehearsed “duck and cover” drills at school, just in case the Russians dropped an atomic bomb down the street.

I wasn’t born yet, but distinctly remember gathering around the TV in class — just as Linklater recalls doing for those early NASA launches — some 17 years later to watch an American teacher sent up to space. (Whereas Apollo 11 made Linklater’s generation feel like anything was possible, the Challenger explosion crushed my first-grade dreams of wanting to be an astronaut.) For me, the world has always been a place where humans were capable of reaching the moon, which makes “Apollo 10 1/2” a uniquely fascinating account of living through the moment when those who came before witnessed that “giant leap for mankind.”

In these divisive times, the words “Make America Great Again” have been hijacked to paint all Trump supporters as white supremacists, but for many — like my own right-leaning Texas friends and relatives — they’re more of a reminder of the way it felt in 1969, when the country was breaking barriers in science and industry. In one scene, using animation technology to draw over archival television footage, Linklater samples the speech President John F. Kennedy gave at Houston’s Rice University, in which he said, “We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard.”

“Apollo 10 1/2” is above all a nostalgia trip for Americans who sat glued to their televisions as the country made one of its greatest scientific achievements. (Depending on just how autobiographical it is, the film suggests that Linklater spent the afternoon at the nearby AstroWorld amusement park, only to fall asleep in front of the TV while Armstrong made his moon walk.) But it’s also a teleportation device for those who weren’t there, loaded with everyday details about what life was like — the kind of observations that made the director’s “Boyhood” resonate so strongly with millennial audiences.

Linklater takes the appealing concept of putting a kid in the lunar module, teased right there at the outset, and sets it aside for more than 52 minutes. “Let me tell you a little bit about life back then,” narrator Jack Black offers cheerily, and off we go on an entirely different ride down memory lane. He describes growing up in a city “with no sense of history,” where fast-food chains and newly built suburbs suggested that a future of flying cars couldn’t be far off. He recalls old sci-fi movies, such as “Destination Moon” and “2001: A Space Odyssey,” and contrasts pop bands like the Beatles and the Monkees with trippier tunes, à la Zager and Evans’ “In the Year 2525.” Even advertisers got in on space race fever, as America’s lunar goals became a bona fide cultural phenomenon.

As a narrative, “Apollo 10 1/2” meanders amicably down seemingly endless tangents, and when Linklater finally loops back around to where he left off — with junior astronaut Stan (performed by Milo Coy) barfing in a NASA simulator — it’s not at all clear how the kid’s top-secret moon mission fits into the larger narrative. At least, not at first. Turns out, this movie isn’t so much about space as it is about time travel, or more specifically, taking Linklater and his followers back more than half a century.

Linklater, bless his soul, will never direct a Marvel movie, but his storytelling superpower has always been a laser-sharp recall for the most specific souvenirs of previous eras. It’s half of what makes films such as “Dazed and Confused” and “Everybody Wants Some!” so rich — they’re period movies that don’t feel phony, the way most flashback Hollywood projects do, because Linklater has an uncanny knack for remembering the clothes people wore, the songs they listened to, the way the world was in any given year.

“Apollo 10 1/2” takes that gift one giant leap farther by employing animation to tell the story, the tone of which recalls Mike Judge’s “King of the Hill” series — especially the bits involving Stan’s stoic, beer-drinking father (played by Bill Wise) and hippie sister (Natalie L’Amoreaux). Much brighter and smoother than Linklater’s early-2000s rotoscope experiments, the project blends a number of different techniques and melds them in virtual space: Linklater shot performances with real actors, which were used as references for the CG characters, whom the team (overseen by longtime collaborator Tommy Pallotta) situated in 3D environments. It looks relatively lo-fi but was plenty complicated to pull off, allowing Linklater to seamlessly re-create the era without audiences getting hung up on whether costumes and locations look convincing.

As in “Waking Life,” the technique gives things a dream-like feel, which turns out to be important. Like so many of Linklater’s movies, “Apollo 10 1/2” is ultimately about memory and the funny way it works. “Even if he was asleep,” muses Stan’s mom (Lee Eddy), “he’ll one day think he saw it all,” which explains the parallel lunar mission Stan dreams of making, even if the way it’s intercut with the rest can be confusing at times.

Linklater may be reliving it all from the position of a middle-class white kid in the South Houston suburb of El Lago (frankly, it’s surprising that Stan’s dad didn’t drive them to the launch site to watch with their own eyes), but he checks his privilege in one key scene, as Black describes how activists opposed the money spent on space instead of domestic problems. Just a minute like that, included within this relatively carefree film, makes a world of difference. It shows that Linklater’s no solipsist, even as he packs this time capsule with so many endearing personal details.