Are we alone? And just how big is space? Planetary Society chief scientist Bruce Betz joins us with the answers on this month's Planetary Radio Book Club edition.

Hello again, Planetary Radio listeners and lovers of books about our solar system and beyond.

I'm Matt Kaplan, Senior Communications Advisor for the Planetary Society, the former host of Planetary Radio.

Bruce Betts has completed his series of space books for young people.

The size of space collects many of Bruce's successful and very entertaining attempts

to reduce the vastness of the cosmos to human scale.

The other book, Are We Alone, borrows that greatest of questions that drives so much of science

and is at the core of the Planetary Society's mission.

Bruce is still the only human being who has been heard on every episode of the weekly

planetary radio series, with me for the first 20 years and now with host Sarah Al-Hmed.

But he has done so very much more for us across his many years at the society,

including his brilliant management of the Light Sail Solar Sail Project.

He's a planetary scientist whose PhD studies at Caltech were overseen by our co-founder, Dr. Bruce Murray.

Bruce Betts spent three years at NASA HQ and has crossed the globe in his work for us and others,

including the Planetary Science Institute, where he is an alumnus senior scientist.

You're about to hear much more about my good friend

in this recording of the live-streamed conversation we had

in the society's member community as 2026 gone underway.

We are here to talk about Bruce's latest books.

You see a shelf full of them behind him there.

Here are the two latest, and as I understand it, last books in the series.

Am I correct?

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