Planetary Radio: Space Exploration, Astronomy and Science

Famed astrophysicist and science communicator Adam Frank shares his sense of wonder and humor in a live conversation about his excellent new book, “The Little Book of Aliens.” Join Adam and host Mat Kaplan as they explore the origin of life, the search for extraterrestrial intelligence, and whether all those UFO sightings are worthy of deeper investigation.

Discover more at: https://www.planetary.org/planetary-radi...

Our Solar System is wrapped in a vast, invisible bubble created by the Sun, a protective region that shields Earth and the planets from much of the radiation that fills our galaxy. But until recently, scientists have only had rough sketches of what this boundary looks like and how it behaves.

In this episode of Planetary Radio, host Sarah Al-Ahmed is joined by David McComas, professor of astrophysical sciences at Princeton Universi...

What does it really mean to enter interstellar space, and what have we learned since humanity first crossed the invisible boundary between our Sun and the stars?

In this episode of Planetary Radio, we explore the science of the heliosphere and the realm beyond with Linda Spilker, project scientist for the Voyager mission at NASA Jet Propulsion Laboratory. Drawing on decades of experience with the twin spacecraft, Spilker shares how...

Marcia Smith, the founder and editor of Space Policy Online, joins the show and revisits a conversation we had one year ago, recorded just weeks before the second Trump administration took office. That episode, “The Challenges of Change at NASA,” explored the institutional and political roadblocks to radical change at the U.S. space agency.

A lot has happened since that show, including DOGE, mass staff departures, a dra...

As 2025 comes to a close, Planetary Radio looks back on a year that reshaped space exploration, through stunning discoveries, major milestones, unexpected challenges, and the people who carried science forward through it all.

In this episode, Sarah Al-Ahmed, host and producer of Planetary Radio, is joined first by Kate Howells, public education specialist at The Planetary Society, to share results from The Planetary Society’s...

2025 was one of the most consequential years for space policy in modern U.S. history.

In this special year-in-review episode, Planetary Radio takes a deep dive into what happened behind the scenes in U.S. space policy and advocacy as NASA faced unprecedented proposed cuts to its science programs. With nearly half of NASA’s science budget at risk, dozens of missions threatened, and months of leadership uncertainty at the agenc...

It was such a delight to feature work by our own Kate Howells in The Planetary Society’s member book club. We keep Kate busy as our public education specialist, but she found time to write about many of her favorite natural satellites in this richly illustrated edition. Join her and book club host Mat Kaplan for a journey taking us from our own Moon, past Europa, Titan, and many more, and out across a galaxy that is no doubt ...

Thirty years ago, NASA’s Galileo spacecraft became the first mission to orbit Jupiter, opening a new chapter in our exploration of the outer Solar System. Over eight years around Jupiter, Galileo transformed how we understand Jupiter and its moons, revealing a powerful and dynamic planetary system, uncovering evidence for oceans hidden beneath icy worlds, and reshaping the search for life beyond Earth.

To mark the 30th annive...

Why do we explore space, and why does science matter in the first place?

In this Space Policy Edition rerun, Planetary Society Chief of Space Policy Casey Dreier revisits a deeply influential 2020 conversation with philosopher and ethicist J. S. Johnson-Schwartz, author of The Value of Science and Space Exploration. As debates over NASA’s budget and the future of space science continue to resurface, this conversation remains ...

The 2025 International Mars Society Convention convened at the University of Southern California this October for three days of passionate discussion about humanity’s future on the red planet. Speakers explored science, policy, technology, AI, synthetic biology, and the long-term path toward becoming a multi-planet species.

In this episode, Mat Kaplan, senior communications adviser at The Planetary Society, shares his convers...

NASA’s twin ESCAPADE spacecraft have finally launched on their journey to Mars. Designed to study how the solar wind interacts with Mars’ patchy magnetic fields and drives the loss of its atmosphere, ESCAPADE is NASA’s first dual-spacecraft mission to the Red Planet and a major milestone for the SIMPLEx program’s small, low-cost planetary explorers. The mission began its voyage aboard Blue Origin’s New...

This week on Planetary Radio, we’re sharing a special conversation from our friends at the Smart Girl Dumb Questions podcast. Host Nayeema Raza sits down with The Planetary Society’s Chief of Space Policy, Casey Dreier, to explore one of the most common questions in space exploration: Why does space matter, and is it really worth the cost?

Casey breaks down how space exploration impacts daily life, from GPS and weather ...

There was a time when almost everyone, from Alexander Graham Bell to the Wall Street Journal, believed there was a supremely intelligent civilization on Mars, one that was probably trying to talk to Earthlings. Most of this belief could be traced to an amateur astronomer and charismatic speaker named Percival Lowell. David Baron tells this story in “The Martians: The True Story of an Alien Craze that Captured Turn-of-the-Cent...

When his filmmaking career stalled during the pandemic, Toby Lockerbie turned to the one place that had never stopped inspiring him: the Universe. With no background in visual effects, he taught himself the tools needed to transform complex space science into cinematic stories using everyday objects and beautifully crafted visuals to make the Cosmos feel human. His channel, Epic Spaceman, now reaches millions and has earned multipl...

The Planetary Society heads to TwitchCon 2025 to explore how scientists and educators use livestreaming to share the excitement of discovery. We begin with Moohoodles, one of Twitch’s pioneering space science streamers and co-host of the live panel “The Planetary Society: Space, Time, and You.” She explains how she built a thriving community around astrobiology and space exploration long before Twitch even had a S...

In 1996, a controversial claim of fossilized life in a Martian meteorite ignited a golden age of Mars exploration. Nearly 30 years later, a potential biosignature detected by the Perseverance rover at Jezero Crater has sparked…nothing, not even a formal effort to revive the beleaguered robotic Mars Sample Return project. Why did the claims surrounding the Allan Hills meteorite (which were ultimately rejected) kick off 25 yea...

If we ever meet intelligent extraterrestrials, will we even be able to talk about physics? Physicist Daniel Whiteson of UC Irvine and cartoonist Andy Warner join Sarah Al-Ahmed to explore one of science’s strangest and most profound questions: if alien civilizations exist, would their understanding of the Universe look anything like ours?

Their new book, “Do Aliens Speak Physics?”, discusses the nature of knowledg...

What happens in space doesn’t stay in space. Historian Dagomar Degroot joins Planetary Radio host Sarah Al-Ahmed to explore how shifting solar cycles, volcanic eruptions on Venus, Martian dust storms, and even mistaken sightings of lunar forests have influenced life, science, and society on Earth. His new book, “Ripples on the Cosmic Ocean: An Environmental History of Our Place in the Solar System,” reframes the S...

In this second installment of Planetary Radio’s coverage from the 2025 NASA Innovative Advanced Concepts Symposium in Philadelphia, Pennsylvania, host Sarah Al-Ahmed highlights more of the technologies presented by the NIAC fellows.

Mary Knapp of MIT Haystack Observatory shares her team’s Great Observatory for Long Wavelengths project, a space-based radio array designed to detect magnetic fields around distant exoplanet...