The fear that the Earth could be destroyed by a killer asteroid is an anxiety that pops up all the time in fiction and is grounded in fact. But funnily enough—actually being pancaked by a giant space rock? Not something you need to spend a whole lot of time worrying about! And that’s because a bunch of NASA scientists and engineers are already worried about it for us. In this episode, science journalist Dr. Robin George Andrews tells us the story of NASA’s first-ever mission to defend the planet, which is the subject of his new book, How to Kill an Asteroid. This episode was written and produced by Sofie Kodner. It was edited by Willa Paskin and Evan Chung. Decoder Ring is produced by Willa Paskin, Evan Chung, Max Freedman and Katie Shepherd, with help from Sofie Kodner. Derek John is Executive Producer. Merritt Jacob is Senior Technical Director. If you have any cultural mysteries you want us to decode, email us at DecoderRing@slate.com Want more Decoder Ring? Subscribe to Slate Plus to unlock exclusive bonus episodes. Plus, you’ll access ad-free listening across all your favorite Slate podcasts. Subscribe now on Apple Podcasts by clicking “Try Free” at the top of the Decoder Ring show page. Or, visit slate.com/decoderplus to get access wherever you listen. Learn more about your ad choices. Visit megaphone.fm/adchoices