Astronomy Cast is one of the most informative and entertaining science podcasts that I have found to date. The chemistry between the hosts would be enough to make me keep listening, even if the subject matter wasn’t fascinating. Astronomy Cast episodes are short and focused, usually on a single aspect of the larger universe in which we live.

The hosts of Astronomy Cast are Dr. Pamela Gay, a professor of Physics at the Southern Illinois University Edwardsville, and Fraser Cain, publisher of Universe Today. Dr. Gay is the kind of scientist that somehow never makes it into the movies. Her sense of humor and her joyful enthusiasm for science make her an easy person to listen to and to learn from. She picks brilliantly gonzo phrases to describe her topics, and she never hesitates to let the audience know where the gaps in current scientific theory lie.

Astronomy Cast’s motto is “Not only what we know, but how we know what we know.” They don’t just recite facts. That would be boring. Instead, Fraser Cain acts as the audience’s stand-in, asking questions and trying to understand the concepts that Dr. Gay describes. He insists that Dr. Gay justify the opinions of modern astronomy. Often they will work through a topic, like black holes, from the first mathematical thought experiment right up to the most recent physical evidence of black holes eating stars. Astronomy Cast highlights the most important aspect of science: That it is a process, and one that inherently self-correcting.

The library of old Astronomy Cast episodes is huge. A new listener could spend days listening to old episodes in order, or pick which episodes to listen to based on subject matter. The Astronomy Cast website is set up to aid the listener in doing just that, with the episodes classified into groups like “Amateur astronomy,” “Planetary science,” and “Space flight.” The episodes themselves are short, usually no more than a half an hour, and are well-paced and edited so as to make it seem that the hosts have stayed on topic the whole time.

As a non-scientist and a science fiction writer, I have found Astronomy Cast to be an inspiration. Dr. Pamela Gay and Fraser Cain have a great time recording the episodes, and it’s easy to be sucked into their enthusiasm. They aren’t afraid to explore the furthest implications of the theories they describe — one of Mr. Cain’s favorite phrases is “but what if?” They make me want to spin science concepts into stories, and they explain the science well enough that I feel confident when I’m staring at a cursor on a blank screen.

I highly recommend Astronomy Cast to anyone who wants to learn about astronomy, or anyone who just wants to listen to two unapologetic geeks talk about the science they love. The content is, I believe, appropriate for both children and adults. Their website is www.astronomycast.com, or look them up on iTunes.