Over a billion lightyears ago, in the darkness of outer space, a collision of black holes sent out a fleet of invisible waves that were headed right toward planet Earth. The waves were so powerful they could ripple spacetime but most people on Earth didn't believe the waves were real. SPOILER ALERT: The waves are called gravitational waves and…they are real! Astrophysicist Dr. Wanda Díaz Merced tells the story of what happened when they hit Earth in 2015 and how scientists came to learn to use senses beyond eyesight to detect the waves. We also learn from Dr. Stavros Katsanevas about the building of a giant gravitational wave catcher called “The Interferometer.” This episode also explores how to persist in the face of doubt as we learn Wanda's tale of going blind and learning how to listen to the stars.

Learn about the storytellers, listen to music, and dig deeper into the stories you hear on Terrestrials with activities you can do at home or in the classroom on our website, Terrestrialspodcast.org. 

Watch the interferometer come to life, disco style, and find even MORE original Terrestrials fun on our Youtube.

Badger us on Social Media: @radiolab and #TerrestrialsPodcast 

Support for Terrestrials is provided by Science Sandbox, a Simons Foundation Initiative, and the Arthur Vining Davis Foundations.

The Shovels: Dig Deeper

For each episode of Terrestrials, we provide a selection of activity sheets, drawing prompts, musical lessons, and more. We call them “shovels” because we hope they will help you (and your friends, family, students, neighbors, etc) dig more deeply into the world! You can do them at home, in the classroom, outside, or in the privacy of your own mind. We hope you enjoy!If you want to share what you’ve made, ask an adult share it on social media using #TerrestrialsPodcast and make sure to tag @Radiolab

Draw -  Use your ears to draw! In this very special drawing prompt, Wendy Mac and the DrawTogether team pull in an actual rockstar to play you various favorite sounds to draw. It's a feast for the mind, ears, and hands. Grab a pencil, pen, crayon, marker, anything, and check it out here!

Play 🎶 - Learn how to play the chords to the song “UNIMAGINABLE”

Do - Get crafty with a fun activity sheet!  

This week’s storyteller is Dr. Wanda Díaz Merced.

Want to keep learning? Check out these resources to learn about the time-bending power that is the gravitational wave:

Get to Wanda a little better; watch her TED talk!Take a tour of the world’s first interferometer! (Free monthly tours in person in Richland, WA)Train yourself to use sound for signal detection in astronomy. Learn more about asteroseismology with the wonderful Hank Green!Spooked by the idea of the infinite universe? Listen to John Green’s “Against Nihilism” (probably best for 13 and up)!

Terrestrials is a production of WNYC Studios, created by Lulu Miller. This episode is produced by Ana González, Alan Goffinski and Lulu Miller. Original Music by Alan Goffinski. Help from Suzie Lechtenberg, Sarah Sandbach, Natalia Ramirez, and Sarita Bhatt. Fact-check by Natalie Meade. Sound design by Phoebe Wang with additional engineering by Joe Plourde. Our storytellers this week are Dr. Wanda Díaz Merced and Dr. Stavros Katsanevas. Transcription by Caleb Codding.

Our advisors are Theanne Griffith, Aliyah Elijah, Dominique Shabazz, John Green, Liza Steinberg-Demby, Alice Wong, and Tara Welty.

Terrestrials is supported in part by Science Sandbox, an initiative of the Simons Foundation.

Have questions for us, badgers? Badger us away! Your parent/guardian should write to us along with you, so we know you have their permission, and for maybe even having your ideas mentioned on the show. Email terrestrials@wnyc.org

Sign up for Radiolab for Kids’s newsletter! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up here.

Radiolab for Kids and Terrestrials are supported by listeners like you. Support Radiolab by becoming a member of The Lab today.

Follow Radiolab on Instagram, X Facebook, Threads and TikTok @radiolab.

Support for Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, the Kalliopeia Foundation and the John Templeton Foundation.