Planetary Radio: Space Exploration, Astronomy and Science

Gentry Lee spent nearly five decades at NASA's Jet Propulsion Laboratory, and in that time he helped shape some of the most ambitious missions in the history of space exploration. A new documentary, “Starman,” chronicles his career and the big question that runs through it: is there life beyond Earth? Lee worked on every NASA mission to land on Mars, helped Carl Sagan bring the Universe to living rooms around the world with “Cosmos,” and oversaw dozens of active missions as Chief Engineer for the Solar System Exploration Directorate at JPL. Few people have had a front-row seat to the Space Age quite like him.
In this episode, host Sarah Al-Ahmed sits down with Gentry at Planetary Society headquarters just one day after his retirement from JPL. He reflects on the colleagues who shaped him, the missions that changed our understanding of the Solar System, and why the search for life beyond Earth remains the most profound endeavor humanity has ever undertaken.
Discover more at: https://www.planetary.org/planetary-radio/2026-starman
See omnystudio.com/listener for privacy information.

Is the United States really in a new space race with China? Or is that framing missing the bigger picture?
In this Space Policy Edition of Planetary Radio, Casey Dreier, chief of space policy at The Planetary Society, sits down with Patrick Besha, former NASA strategic advisor on China, to explore the realities behind China’s rapidly advancing space program. They discuss how China’s political system shapes its long-term space strategy, why the rhetoric about a “space race” may be misleading, and how competition between the United States and China in space is likely to unfold over the coming decades.
Discover more at: https://www.planetary.org/planetary-radio/spe-us-china-space-race
See omnystudio.com/listener for privacy information.

NASA has announced a major restructuring of the Artemis program, reshaping the roadmap for returning humans to the Moon.
At a February 27 press conference, agency leadership addressed the rollback of Artemis II following post–wet–dress–rehearsal testing and unveiled significant changes to upcoming missions, including shifting Artemis III from a planned lunar landing to a low-Earth-orbit rendezvous and integrated systems test. In this episode, you’ll hear remarks from NASA Administrator Jared Isaacman and Lori Glaze, Moon to Mars program manager and acting associate administrator for NASA’s Exploration Systems Development Mission Directorate. They explain what happened with Artemis II and why NASA is changing course.
Then, host Sarah Al-Ahmed is joined by Jack Kiraly, director of government relations at The Planetary Society, and Ari Koeppel, AAAS science and technology policy fellow, to unpack the political and strategic forces behind this shift and what it means for the future of lunar exploration.
In What’s Up, Bruce Betts, our chief scientist, looks back at Apollo 9, the Earth-orbiting mission that proved the Lunar Module could operate independently before NASA attempted a lunar landing.
Discover more at: https://www.planetary.org/planetary-radio/2026-artemis-update
See omnystudio.com/listener for privacy information.

Could a single ancient impact have briefly transformed one of the Solar System’s darkest moons into a cryovolcanic world?
When Voyager 2 flew past Uranus in 1986, it captured the only close-up images we have of Umbriel, a heavily cratered, charcoal-dark satellite long considered geologically inactive. But one feature stands out: a bright ring inside the 131-kilometer-wide Wunda crater.
In this episode, Sarah Al-Ahmed speaks with Adeene Denton, NASA postdoctoral program fellow at the Southwest Research Institute, about her team’s new study published in the Journal of Geophysical Research: Planets. Using shock physics simulations, Denton and her colleagues reconstruct the impact that formed Wunda crater to determine what Umbriel’s interior must have been like at the time. Their modeling explores whether impact-induced cryovolcanism can explain the bright deposits observed on the crater floor.
Then, in What’s Up, Bruce Betts, chief scientist of The Planetary Society, joins Sarah to break down one of the key mechanisms that keeps icy moons from freezing solid, tidal heating driven by orbital resonance.
Discover more at: https://www.planetary.org/planetary-radio/2026-cryovolcanism-on-umbriel
See omnystudio.com/listener for privacy information.

They informed and entertained together throughout the first 20 years of Planetary Radio. Listen in as the Society’s chief scientist and book club edition host Mat Kaplan share the mic once again for a delightful conversation about Dr. Betts’ two new space books for young people. “Are We Alone?” introduces the search for life across the Universe, while “The Size of Space” collects many of Bruce’s brilliant and hilarious ways to cut our Solar System down to human size.

Discover more at: https://www.planetary.org/planetary-radio/book-club-bruce-betts
See omnystudio.com/listener for privacy information.