Dust off any pop fan's old iPod from the beginning of the decade, and there's a high chance you'll find Owl City's maddeningly catchy "Fireflies" in its library. With saccharine vocals, cuddly electronic blips and a Top 40-friendly hook, the track -- originally written about a twenty-something's struggle with insomnia -- quickly became a radio standby, and logged two weeks at No. 1 on the Billboard Hot 100 in November 2009.

Fast-forward eight years -- for Owl City singer-songwriter Adam Young, three albums since his breakthrough -- and "Fireflies" had been relegated to karaoke nights and occasional throwback radio spins. That is, until this past month, when its streaming numbers nearly tripled.

Since the chart week ending June 15, “Fireflies” has grown from 1.4 million total on-demand weekly streams to cracking 4 million, and has stayed pretty steady in its bump (3.8 million streams in the chart week ending July 20). The push was enough to propel "Fireflies" onto the Rock Streaming Songs chart, where it reached No. 8 last week. That’s right: Owl City’s “Fireflies,” in the top 10 of a Billboard chart, in 2017!

Confused? So was Owl City's Adam Young when his management called the singer, now 31, to relay those baffling numbers. "They called the record label, and they were kind of like, ‘Are you guys seeing what we’re seeing?'" Young tells Billboard. "I wouldn't have known unless my management company had been like, ‘Hey Adam, did you realize this?'”

Like many success stories in 2017, this one started with a tweet. Around April, the Internet meme-iverse had begun pestering Young with a string of "Fireflies"-related memes seemingly united by one burning question -- just what did he mean when writing the puzzling "Fireflies" lyric, "I get a thousand hugs, from 10,000 lightning bugs?"

"I loved how people were trying to figure it out," Young says. "My idea was to play along with fans and write a really in-depth, hard-to-understand, dense reasoning as to how, in fact, it is possible for a guy to receive 1,000 hugs from 10,000 lightning bugs, at the molecular level."

The answer required ample mental gymnastics -- plus concrete research on the anatomy of fireflies "to a depth that I had not done before," Young adds with a laugh. Soon, fans had their answer in the form of a two-paragraph, heavily mathematical message Young posted to social media on June 20, signed off with a cordial, only half-joking note: "Please don’t hesitate to reach out with any further questions."

Young, not shockingly, is an avid meme-er himself. "I’ll send, like, the ‘me gusta’ face to my girlfriend, all the time," he says, explaining that he leans toward the "old-school."

In 2017, it seems, knowing your memes pays off: Young's tweet response has garnered 190,000 likes and 88,000 retweets, sending fans back to "Fireflies" for the first time in years. The fan interaction means more to Young than the increased numbers. "It’s almost like the song doesn't even belong to me anymore, because it’s taken on this life of its own," he adds. "I think that is the highest honor that an artist can feel."

Scrolling through the dozens of "Fireflies" memes that have begun cropping up on Instagram and Twitter, Young says he was brought back to memories of his parents' basement in southern Minnesota, where he penned the original track at age 21. "There’s so many fireflies where I live in Minnesota,” he says. “If you look across your front lawn or your backyard, there are millions. So I was channeling that feeling and thinking, if there’s 10,000 [fireflies], and there’s one of me, it should be easy for 10,000 of these insects to at least give me 1,000 hugs. Because that’s what it feels like when you’re running through your backyard… you’re running into these bugs, there’s so many of them... you can outstretch your arms and grab a whole bunch like you’re hugging them."

After releasing most recent album Mobile Orchestra in 2015 and recording the track "Waving Through a Window" for Tony winner Dear Evan Hansen, Young is readying a collection 15 new songs he says he plans to release over the next year. For the singer-songwriter, the opportunity to press pause on his current work and reflect -- mathematically, for the first time! -- on his biggest hit was welcomed.

"It feels great. Finally, the secret is out!” he says, laughing. "Here's the answer, after all these years.”