I'm Kea Miyakhanatees. This is NPR's Book the Day. Time travel sounds cool, but the concept always hits a quagmire. If you go back and try to change the past, who knows what you're screwing up in the present. That's what seventh grader Rahim Reynolds learns after his best friend,

Kasia, invents a cell phone for him that kind of accidentally transports him back to 1997.

Their adventure to travel back to present-day Philly, where they live,

forms the plot of The Rhythm of Time,

a new children's book by crime writer S.A. Cosby and musician Amir Kwestlove Thompson.

They both chat here with NPR's Aisha Rosco about writing time travel for young readers.

In the U.S., national security news can feel far away from daily life.

Distant wars, murky conflicts, diplomacy behind closed doors on our new show,

Sources and Methods. NPR reporters on the ground bring you stories of real people,

helping you understand why distant events matter here at home.

Listen to sources and methods on the NPR app or wherever you get your podcasts.

Musician Questlove found himself struggling with all that downtime during the pandemic lockdown.

I'm living a real 24-hour day where the only thing I can look forward to is DJing online for three hours and figuring out what I have to do for Fallon on my iPhone. Amir Questlove Thompson, drummer for

the roots, band leader for Jimmy Fallon, Oscar-winning director of Summer of Soul, was used to being

busy, really busy.

So he started thinking about something he'd always wanted to do, but didn't think he could

actually pull off.

In my mind, I'm so obsessed with time travel, but I'm one of those nerds that, yeah, I'm sorry.

It took me till the pandemic to watch Star Wars, the complete series, and

things that nerds are supposed to know already, like nerd one-on-one stuff. I just thought that

I can't write a book about time travel and stuff. Like, I don't even know what the terms do

use. It was suggested that Questlove reconnect with somebody he'd been introduced to a few years back.

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