Planetary Radio: Space Exploration, Astronomy and Science

The Planetary Society


Planetary Radio brings you the human adventure across our solar system and beyond. We visit each week with the scientists, engineers, leaders, advocates and astronauts who are taking us across the final frontier. Regular features raise your space IQ while they put a smile on your face. Join host Mat Kaplan and Planetary Society colleagues including Bill Nye the Science Guy, Bruce Betts, and Emily Lakdawalla as they dive deep into the latest space news. The monthly Space Policy Edition takes you inside the DC beltway where the future of the US space program hangs in the balance. Visit for the space trivia contest, an episode guide, and much more.

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1119 episodes

Looking back on Voyager’s 45th Anniversary

Planetary Radio’s creator Mat Kaplan guest hosts for this look back at the Jet Propulsion Lab’s celebration of the 45th anniversary of the Voyager mission. Stick around for his conversation with Ann Druyan, creative director for the Golden Record carried by the probes. Mat and Bruce Betts reunite for this week’s What’s Up and space trivia contest. Discover more at: See for privacy information.

1h 15m
Mar 08
Space Policy Edition: The Tricky Ethics of Space Settlement

Humanity is on the cusp of attempting permanent settlement on other worlds. But who gets to go? How will we govern ourselves or enforce laws off Earth? How can you have property rights, labor rights, or even individual rights when the very air you breathe is limited and potentially controlled by your employer? Dr. Erika Nesvold, astrophysicist and author of the new book “Off-Earth: Ethical Questions and Quandaries for Living in Outer Space” explores the ethical challenges facing our species as it dips its toe into living beyond our home planet. See for privacy information.

1h 11m
Mar 03
The Canadian Lunar Rover with Peter Visscher

In this week’s episode, Director of Canadensys West Peter Visscher fills us in on the upcoming Canadian lunar rover. Visscher has been working on the rover for years. Bruce Betts also returns to the show for another installment of What's Up. Discover more at: HTTPS://WWW.PLANETARY.ORG/PLANETARY-RADIO/2023-CANADIAN-LUNAR-ROVER-PETER-VISSCHER See for privacy information.

Mar 01
Martian rock collecting: From meteorites to Mars Sample Return

Exciting updates to the plans to return samples from Mars to Earth are underway. Meenakshi Wadhwa, principal scientist for Mars Sample Return at NASA JPL, shares what we have learned from our studies of Martian meteorites and fills us in on the upcoming Mars Sample Return missions. Stick around for our review of the night sky and a look back at this week in space history in What’s Up with Bruce Betts.   Discover more at:  See for privacy information.

Feb 22
Are we alone? The search for alien technosignatures

A new volunteer science project to search for alien technosignatures has launched! Jean-Luc Margot and Megan Li from UCLA join us to share the exciting debut of their Planetary Society STEP Grant-funded SETI project on Zooniverse. Our public education specialist Kate Howells reflects on the tenth anniversary of the Chelyabinsk Meteor Event, and don’t miss your chance to win a comfy Planetary Society beanie in this week’s Space Trivia Contest. Discover more at: HTTPS://WWW.PLANETARY.ORG/PLANETARY-RADIO/2023-ARE-WE-ALONE-SETI See for privacy information.

Feb 15
More on Mars’ Watery History

Mars expert Tanya Harrison shares the details on some of the newest discoveries about Mars’ history, including the discovery of an impact crater thought to be linked to a megatsunami in Mars’ ancient ocean and the discovery of opals, a water-rich gem, in Gale Crater. Stick around for What’s Up as we let you know what to look for this week in the night sky. Discover more at:  See for privacy information.

Feb 08
Space Policy Edition: The White House's Matt Daniels on the U.S.'s New Cislunar Strategy

For the first time in history, the White House laid out a national policy for science and technology in the vast expanse of cislunar space. This policy is not just for NASA — it's an all-of-government approach to establish the infrastructure and capabilities to enable a multitude of national and private actors to reach for the Moon and its environs. Dr. Matt Daniels of the White House's Office of Science and Technology Policy chaired the group that defined this new strategy; he joins the show to discuss the strategy, its ambitions, and implications for the future of lunar exploration and development.  Discover more at: See for privacy information.

1h 17m
Feb 03
JWST confirms its first exoplanet

The James Webb Space Telescope has confirmed the discovery of its first exoplanet. Jacob Lustig-Yaeger, one of the leads on the team that made the detection, joins us to discuss the details. We share info on the Juno mission to Jupiter's next flybys of Io, let you know how to spot the "green comet" visiting our part of the Solar System, and provide insights on the night sky in What's Up. Discover more at See for privacy information.

Feb 01
Juno Journeys to Jupiter’s Moons

Dive into the latest discoveries about Jupiter’s moons Ganymede, Europa, and Io with Scott Bolton, the principal investigator for NASA’s Juno mission. We share analysis of the data collected by the spacecraft and look forward to upcoming exploratory missions to Jupiter’s moons from ESA and NASA. Stick around for this week’s What’s Up and our space trivia contest. Discover more: at See for privacy information.

Jan 25
Martian Mic Drop

Jason Achilles, a musician who partnered with NASA’s Jet Propulsion Laboratory to help put one of the first microphones on Mars, shares his journey and the joy of listening to the sounds of Mars. We also highlight an upcoming opportunity to view comet 2022 E3 (ZTF). Stick around for more on the night sky and our space trivia contest with What’s Up. Discover more at: See for privacy information.

Jan 18
Celebrating NASA’s Artemis I mission to the Moon

Jeremy Graeber, the assistant launch director at Kennedy Space Center in Florida, joins us to recount his experience on the night of Artemis I’s historic launch. We celebrate the success of the mission and share a short segment about The Planetary Society’s new Space Life Goals list. Bruce Betts pops in to share more about this week in space history and what to keep an eye out for in the night sky in this week’s What’s Up. Discover more at: HTTPS://WWW.PLANETARY.ORG/PLANETARY-RADIO/2023-CELEBRATING-ARTEMIS-1 See for privacy information.

Jan 11
Space Policy Edition: JPL Director wants "every brain" to have the chance to work in space exploration

After the delay of the Psyche mission, an independent review board faulted management and workforce problems at NASA's Jet Propulsion Laboratory as one of the causes. This month we feature the JPL Director, Dr. Laurie Leshin, to discuss what the lab is doing in response to these critiques, how NASA can compete with the private sector for top talent, and why our society needs to improve the diversity of its workforce to ensure every brain possible can work in space exploration. See for privacy information.

1h 3m
Jan 06
Planetary Radio stories with Mat Kaplan

New host Sarah Al-Ahmed bids a fond farewell to Mat Kaplan, Planetary Radio’s former host, with a heartwarming compilation of messages from fans, followed by a special interview with Mat about his two decades as creator and producer of the show. Be sure to catch Sarah and Bruce Betts in this week’s What’s Up as they share a special gaming-themed trivia question. Discover more at HTTPS://WWW.PLANETARY.ORG/PLANETARY-RADIO/2023-STORIES-WITH-MAT-KAPLAN See for privacy information.

1h 4m
Jan 04
Planetary Society All-Stars Review the Year in Space

It’s Mat Kaplan’s last episode as host of Planetary Radio. He has gathered several of his colleagues to celebrate an outstanding year across the Solar System and beyond. New host Sarah Al-Ahmed sticks around to join Bruce Betts and Mat for her first What’s Up appearance, including listeners’ suggestions for what Mat should take on next! Discover more at See for privacy information.

1h 8m
Dec 28, 2022
Artemis 1 Orion capsule comes home, and the best of Planetary Radio

Host Mat Kaplan returned to Naval Base San Diego to greet the return of the Artemis 1 Orion spacecraft aboard the USS Portland. Stay with us for a collage of entertaining excerpts of 10 of the very best Planetary Radio episodes produced over the last two decades. Incoming host Sarah Al-Ahmed points to a new article about the JWST’s stunning infrared image of Neptune. Don’t miss Mat serenading Bruce Betts in this week’s What’s Up! Discover more at See for privacy information.

1h 16m
Dec 21, 2022
One Last Blast: Author of ‘The Martian’ Andy Weir with JPL Chief Engineer Rob Manning

A rollicking conversation with two of the most entertaining, most creative Planetary Radio guests across our 20-year history about the role of creativity in space and life. Andy Weir’s “The Martian” and “Project Hail Mary” have been New York Times number one bestsellers. Rob Manning oversees all engineering operations at the Jet Propulsion Lab, and knows as much as any human being about how to land on the red planet. Sarah Al-Ahmed helps Mat Kaplan celebrate the success of Artemis 1, while Bruce Betts receives his 20th anniversary gift from Mat! Discover more at See for privacy information.

1h 23m
Dec 14, 2022
Scientist and Hubble Repairman John Grunsfeld

John Grunsfeld didn’t just ride the Space Shuttle into orbit five times. He accumulated two-and-a-half days of spacewalk time as he worked on the Hubble Space Telescope. The former NASA associate administrator returns to Planetary Radio for a very personal conversation with Mat Kaplan. We’ll also attend a screening of the great new documentary, “Goodnight Oppy” about the Mars Exploration Rovers. Sarah Al-Ahmed celebrates the 50th anniversary of the last Apollo moon mission, and Bruce Betts continues that theme with the new space trivia contest. Discover more at See for privacy information.

1h 15m
Dec 07, 2022
Space Policy Edition: NASA's Economic Impact with Alex MacDonald and Joshua Drucker

NASA supports nearly 340,000 jobs spread throughout every state in the union, generates billions of dollars of tax revenue, and invests in critical high-tech, high-skilled workers. But how do we know this? A new report, prepared by a team at the University of Illinois Chicago and sponsored by NASA's Chief Economist, provides the sound economic analysis behind understanding the immense benefit of the U.S. space program. We dive into how this analysis is done, how to interpret the results, and why this information is critical for developing good space policy. Discover more here: See for privacy information.

1h 13m
Dec 02, 2022
A Happy 20th Anniversary for Planetary Radio

Join our celebration with Planetary Society chief executive officer Bill Nye, Society co-founder Louis Friedman, and chief operating officer Jennifer Vaughn. Incoming Planetary Radio host Sarah Al-Ahmed calls our attention to several of the Society’s biggest accomplishments in 2022, and Bruce Betts shares not-so-random space facts about our public radio show and podcast. Discover more at See for privacy information.

1h 18m
Nov 30, 2022
Giving the University of Arizona Mirror Lab a spin

It has been on host Mat Kaplan’s bucket list for years. Join him for a tour of the cavernous Richard F. Caris Mirror Lab at the University of Arizona, where the mirrors for the Giant Magellan Telescope or GMT are being spun into reality. Want your own GMT? You might win a model kit when Bruce Betts delivers this week’s What’s Up space trivia quiz. Stumped by what to get that space nerd in your life? Check out The Planetary Society’s gift guide! Mat and Sarah Al-Ahmed share their favorite suggestions. Discover more at See for privacy information.

1h 9m
Nov 23, 2022
Voyager Mission Project Scientist Linda Spilker

She has been heard on Planetary Radio more than any other guest. Linda Spilker returns in her new role as the Voyager project scientist, following the legendary Ed Stone’s half-century in that job. Linda provides an update on the interstellar journey. The Planetary Society’s LightSail 2 may be only hours from the end of its very successful mission. LightSail Program Manager Bruce Betts makes a special up-front appearance to prepare us for this milestone. And incoming Planetary Radio host Sarah Al-Ahmed introduces The Planetary Academy, a terrific new opportunity for young explorers. Discover more at See for privacy information.

Nov 16, 2022
Space Policy Edition: What the Congressional Midterms Means for Space Science

Next year a new class of elected officials will enter Congress and usher in changes to the political focus and leadership of key space and science committees. Dr. Bethany Johns, the deputy director of Public Policy for the American Astronomical Society, joins the show to discuss how her organization is preparing for the change, what issues they intend to focus on, and how the scientific community can engage with members of both parties to ensure continued investment in U.S. scientific capability. Discover more here: See for privacy information.

Nov 11, 2022
Ann Druyan wishes you a happy Sagan Day

November 9 would have been our co-founder Carl Sagan’s 88th birthday. His professional and life partner, Ann Druyan, returns with a love story — the love between two people that encompassed the Cosmos and had to be shared. Sarah Al-Ahmed will tell us about two missions to Venus. Sarah, too, was inspired by Dr. Sagan. The theme continues with Planetary Society Chief Scientist Bruce Betts in this week’s What’s Up segment. Discover more at See for privacy information.

1h 4m
Nov 09, 2022
Space Policy Edition Bonus: Q&A with Casey Dreier and Bill Nye

While we wait for the result of the upcoming U.S. midterm elections, enjoy this special bonus episode of Space Policy Edition featuring The Planetary Society's Chief Advocate and CEO answering dozens of space policy questions submitted by our members. These twice-annual policy briefings are moderated by Mat Kaplan, and are an exclusive benefit for Planetary Society members. Want to submit questions next time? Join us at Our regular Space Policy Edition episode will be published next Friday, November 11, after the U.S. midterm elections. See for privacy information.

1h 38m
Nov 04, 2022
DART smacked an asteroid! So what’s next in planetary defense?

The success of the Double Asteroid Redirection Test was just one more step toward protecting our world from wayward asteroids and comets. NASA Planetary Defense Officer Lindley Johnson, and Kelly Fast, the agency’s near-Earth object observation program manager, return to our show for a discussion of where we go from here. Sarah Al-Ahmed will tell us about an article that locates the water on and under Mars, while Bruce Betts gets us ready to enjoy the upcoming total lunar eclipse. There’s more to discover at See for privacy information.

Nov 02, 2022
Meet the new Planetary Radio host! (and enjoy a beer with a cosmologist)

Join host Mat Kaplan as he proudly introduces the person who will take on the show he created 20 years ago. Then we’ll join astrophysicist Brian Keating at a joyful gathering of cosmologists who hope to reveal secrets of the Universe through the new Simons Observatory. You might win Brian’s new book about thinking like a Nobel Prize winner in the What’s Up space trivia contest. There’s more to discover at See for privacy information.

Oct 26, 2022
Eyes on the Sky: Spacewatch and the Catalina Sky Survey

The University of Arizona in Tucson hosts two of the most successful asteroid searches on our planet. Together, they have discovered, tracked, and characterized tens of thousands of objects, many of which could pose a threat to Earth. Listen to back-to-back, in-person conversations with the leaders of both efforts. Then we’ll jump to the ever-watchful Bruce Betts for this week’s installment of What’s Up. There’s more to discover at See for privacy information.

1h 2m
Oct 19, 2022
Innovate! NASA’s leading-edge fellows share their amazing projects

Mat Kaplan once again hosted the live webcast from the annual NASA Innovative Advanced Concepts or NIAC symposium. He presents a speed dating sample of highlights. How about a Mars habitat grown from mushrooms? A lunar farside radio telescope built by robots? Or a kilometer-long space station launched by a single rocket? We’ll also join Planetary Society chief scientist Bruce Betts for another What’s Up scan of the night sky and more. There’s more to discover at See for privacy information.

1h 1m
Oct 12, 2022
Space Policy Edition: The Geopolitics of a Successful SETI Detection

What would nation-states do in response to a signal from an alien intelligence? Would they compete for status and control of the message, or hope to gain some technological advantage from its contents? Or would the world shrug its shoulders and move on? Professor Jason Wright, Director of the Penn State Extraterrestrial Intelligence Center, joins the show to discuss a new paper proposing a more nuanced and positive view of world behavior given a potential SETI detection, and how the most likely message we receive may be more ambiguous than we imagine. Discover more here: See for privacy information.

1h 2m
Oct 07, 2022
Grounded: The director of the SOFIA flying observatory looks back

The Stratospheric Observatory for Infrared Astronomy (SOFIA) made its last flight on Sept. 30, 2022. Astronomer Margaret Meixner was onboard as the huge telescope built into a 747 aircraft ended its observations of the universe. Margaret joined us earlier that day to celebrate the great successes of this unique instrument and its team. You may win a signed CD copy of “The Moons Symphony” in the new What’s Up space trivia contest! There’s more to discover at See for privacy information.

Oct 05, 2022