Moon Unit Zappa remembers the moment she became the voice of a generation. It was a school night in 1982 when musician Frank Zappa jostled his 13-year-old daughter awake. Frank needed her in the home studio, stat.

It was the first time Moon had been summoned to her father’s sanctuary, the place where he essentially lived and worked when he wasn’t touring. As she tells it in her new memoir, “Earth to Moon,” out Tuesday, her dad said the five magic words: “We’re gonna record a song.” Groggy, “with unbrushed teeth,” Moon stepped into the soundproof vocal booth.

Headphones were proffered, mics were adjusted. A shiver of excitement ran through her. Frank had obviously read the letter Moon had slipped under the studio door a few days prior, in which she had asked for a chance to “do my ‘Encino accent’ or ‘surfer dood talk’” on his new record — written correspondence being the only way Moon could think to get her father’s attention.

Now it was all happening. With the directive to “talk and improvise in that funny voice,” Moon slipped into character, while Frank asked her to “try to work in ‘gag me with a spoon’ and ‘tubular.’” And it was over in a flash.

Frank, clearly pleased, gave Moon a hug and sent her back to bed. That recording became 1982’s “Valley Girl” — a left-field hit. More than four decades later, Moon’s “Valleyspeak” remains inextricably linked with ’80s SoCal youth culture.

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