Planetary Radio: Space Exploration, Astronomy and Science

If the United States is indeed in a space race with China, then we cannot abandon space science. That’s the claim made by Maxwell Zhu and The Planetary Society’s chief of space policy, Casey Dreier, in a recent op-ed in Payload Space. Their piece contrasted the growing ambitions of China’s coming space science program against the draconian cuts proposed by the White House in 2026. The results are stark: where Chin...

NASA’s Perseverance rover has made one of its most intriguing discoveries yet in Jezero Crater. A rock sample called Sapphire Canyon, drilled from the Bright Angel formation, contains unusual chemical and mineral patterns that may be potential biosignatures.

We begin with remarks from Morgan Cable, research scientist at NASA’s Jet Propulsion Laboratory and co–deputy principal investigator of the PIXL instrument on...

Bill Nye, CEO of The Planetary Society, has officially joined the Hollywood Walk of Fame. In this episode, we speak with Bill about what this rare honor means to him and to science communication. Then, we take you inside the star ceremony in Los Angeles, where friends and fans, including Boston Celtics star Jaylen Brown, paid tribute to his legacy. From there, we shift to Washington, D.C., where NASA faces the threat of deep budget...

Only six people have received The Planetary Society’s Cosmos Award for Outstanding Public Presentation of Science. We were honored to present it to author and historian Dava Sobel in May of 2025. She has created a brilliant library of books that illuminate the lives and work of great scientists, many of whom have been under-appreciated. Each of Dava’s works is also overflowing with the wonder of science and discovery. I...

Pack your cosmic suitcase. This week on Planetary Radio, host Sarah Al-Ahmed is joined by Mark McCaughrean, astronomer, science communicator, and former Senior Advisor for Science & Exploration at the European Space Agency, to talk about his new book, “111 Places in Space That You Must Not Miss.” Part of the popular “111 Places” travel series, the book transforms the guidebook format into a tour across t...

This week on Planetary Radio, we look forward to International Observe the Moon Night on October 4, 2025. Host Sarah Al-Ahmed speaks with Staci Horvath, outreach coordinator for NASA’s Solar System Exploration Division at Goddard Space Flight Center and director of International Observe the Moon Night, and Theresa Summer, astronomy educator at the Astronomical Society of the Pacific, about the history of the event, how it con...

NASA, the crown jewel of 20th-century technocratic liberalism, was the first to land humans on the Moon but now depends on SpaceX for its access to space. Atlantic writer Franklin Foer believes this reflects a diminishment of national capability and that NASA was inadvertently responsible for its own decline. He traces this transformation from a collective pursuit of higher values to a more individualistic — and idiosyncratic...

For decades, Uranus has puzzled scientists. Unlike the other giant planets, Voyager 2’s 1986 flyby suggested the ice giant emitted no excess heat. Now, thanks to new analyses of Voyager data, decades of ground-based and space-based observations, and refined models, scientists have confirmed that Uranus does radiate more heat than it receives from the Sun.

Host Sarah Al-Ahmed speaks with atmospheric scientist Michael Roman (As...

BASILISK, the first esports organization dedicated to promoting science, has teamed up with The Planetary Society and Caltech’s Institute for Quantum Information and Matter to bring the banner of “Science Victory” to gamers around the world. Their roster includes world champions in StarCraft II, chess, Magic: The Gathering, and fighting games, all united by a shared mission to inspire the next generation of scient...

In 2020, the YSES-1 system became the first directly imaged multiplanetary system around a Sun-like star. It features two giant exoplanets orbiting a star just 16 million years old. Now, the James Webb Space Telescope is revealing new insights into these distant worlds. Host Sarah Al-Ahmed speaks with Kielan Hoch, Giacconi Fellow at the Space Telescope Science Institute and principal investigator of the JWST program that captured t...

Author Frank White has interviewed well over 100 astronauts. Almost all of them report the sense of awe they experienced as they looked down or back at Earth, and how deeply this has affected their understanding and appreciation of our planet and the Cosmos. It’s what author Frank White calls The Overview Effect. Frank joined Planetary Society Senior Communications Adviser Mat Kaplan for a deep conversation about the ideas he...

What do “Star Trek,” space advocacy, and the fight to save NASA science have in common? In this episode of Planetary Radio, we share a special panel recorded live at STLV: Trek to Vegas 2025, featuring Robert Picardo, actor and Planetary Society board member who played the Emergency Medical Hologram on ”Star Trek: Voyager,” and Tim Russ, actor, telescope enthusiast, and Voyager’s Lt. Tuvok. They’...

Just three interstellar objects have ever been detected in our Solar System, each arriving from the depths of interstellar space. In this episode, we explore the latest: 3I/ATLAS, a newly discovered interstellar comet first spotted on July 1, 2025.

Bryce Bolin, research scientist at Eureka Scientific, joins host Sarah Al-Ahmed to share what makes this object special. As one of the few astronomers who has studied all three known int...

How do astronauts get quality sleep in space? Erin Flynn-Evans, director of the Fatigue Countermeasures Laboratory at NASA Ames Research Center, joins Planetary Radio to explore how her team studies sleep, fatigue, and circadian rhythms to keep astronauts healthy and mission-ready. She shares how her team translates sleep science into actionable strategies for NASA crews, and how a chance job as a sleep technician led her on a path...

On July 14, 2015, NASA’s New Horizons spacecraft made its historic flyby of Pluto, transforming our understanding of this distant world. Ten years later, we’re celebrating that iconic moment and the mission that made it possible.

We begin with Alan Stern, principal investigator of the New Horizons mission, who reflects on the mission’s origins, its most surprising discoveries, and what comes next as New Horizons c...

Author Andy Weir was as shocked as anyone when The Martian became a top bestseller novel in the US. He repeated that achievement with his equally mind-blowing science fiction masterpiece Project Hail Mary. Former Planetary Radio host Mat Kaplan welcomed Andy in April of 2023 for the first livestreamed author conversation in The Planetary Society's member book club. Now, with the film version of Project Hail Mary approaching, we&rsq...

What happens when scientists, students, space communicators, and refugee engineers float together in zero gravity? Former Planetary Radio host Mat Kaplan joins a remarkable group of flyers aboard a Zero-G flight organized by Space for Humanity. You’ll hear from participants and mentors including Emily Calandrelli, Sian Proctor, and Roxy Williams, as well as Space for Humanity Executive Director Antonio Peronace and Zero-G CEO...

The Vera C. Rubin Observatory has shared its first public images, revealing millions of galaxies, stars, and asteroids in stunning detail. Stephanie Deppe, astronomy content strategist at Rubin Observatory, joins us to explain what makes these images so revolutionary, how the observatory works, and what’s coming next as Rubin prepares for its ten-year Legacy Survey of Space and Time.

Later in the show, we reflect on the life ...