Astronomy Cast Podcast

Astronomy Cast takes a fact based journey through the cosmos as it offers listeners weekly discussions on astronomical topics ranging from planets to cosmology. The show brings the questions of an avid astronomy lover direct to an astronomer. So explore what is known and being discovered about the universe around us.

Ep. 756: SphereX

19 May 2025 at 8:00pm
Astronomy Cast Ep. 756: SphereX By Fraser Cain & Dr. Pamela Gay Streamed live on May 12, 2025. NASA’s newly launched SphereX mission is up & operational and has completed its initial checkout and “first light”. Everything looks good! And now it’s starting its science operations. And that’s good e... Read more...

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Ep. 755: Intermediate Mass Black Holes

12 May 2025 at 8:00pm
Astronomy Cast Ep. 755: Intermediate Mass Black Holes By Fraser Cain & Dr. Pamela Gay Streamed live on May 5, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay. There are stellar-mass and supermassive black holes. But very little evidence of anything in between. Where are all the intermediate-ma... Read more...

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Ep. 754: K2-18b

5 May 2025 at 8:00pm
Astronomy Cast Ep. 754: K2-18b By Fraser Cain & Dr. Pamela Gay Streamed live on Apr 28, 2025. You’ve heard the news! Astronomers are reporting the discovery of biosignatures at K2-18b. Is this proof of life or should we all be more skeptical? It's in the news and people are claiming aliens... but... Read more...

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Ep. 753: Why is the Moon's South Pole So Interesting?

28 Apr 2025 at 8:00pm
Astronomy Cast Ep. 753: Why is the Moon's South Pole So Interesting? By Fraser Cain & Dr. Pamela Gay Streamed live on Apr 21, 2025. I’m sure you’ve heard that all eyes are on the Moon’s southern pole. This is where various NASA and Chinese missions are targeting. What makes this region so specia... Read more...

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Ep. 752: Should We Go to the Moon or Mars Next?

21 Apr 2025 at 8:00pm
Astronomy Cast Ep. 752: Should We Go to the Moon or Mars Next? By Fraser Cain & Dr. Pamela Gay Streamed live on Apr 16, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay There is an ongoing debate on where NASA should go next with humans: to the Moon or Mars. (Or maybe an asteroid or one of Mars... Read more...

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Ep. 751: Vacuum Energy

14 Apr 2025 at 8:00pm
Astronomy Cast Ep. 751: Vacuum Energy By Fraser Cain & Dr. Pamela Gay Streamed live on Apr 7, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay. Even empty space isn’t empty. It’s filled with the quantum fluctuations of spacetime itself. Which can be measured with famous experiments like the Cas... Read more...

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Ep. 750: Supernova Early Warning System

7 Apr 2025 at 8:00pm
Astronomy Cast Ep. 750: Supernova Early Warning System By Fraser Cain & Dr. Pamela Gay Streamed live on Mar 31, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay When enormous stars detonate as supernovae they release a burst of neutrinos that can be the first sign of a coming explosion. Now, as... Read more...

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Ep. 749: Dark Energy Changing Over Time

31 Mar 2025 at 8:00pm
Astronomy Cast Ep. 749: Dark Energy Changing Over Time By Fraser Cain & Dr. Pamela Gay Streamed live on Mar 24, 2025. The Hubble Tension is a vexing problem, with astronomers measuring the expansion of the Universe at different points in its history and getting different results. Errors have most... Read more...

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Ep. 748: Fast Radio Bursts

24 Mar 2025 at 8:00pm
Astronomy Cast Ep. 748: Fast Radio Bursts By Fraser Cain & Dr. Pamela Gay Streamed live on Mar 17, 2025. For the briefest of moments, some dead stars can flash brighter than their entire galaxy (in Radio light) and then live to do it again and again. It’s time for an update on fast radio bursts, ... Read more...

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Ep. 747: Rogue Planets

17 Mar 2025 at 8:00pm
Streamed live on Mar 10, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay Most planets orbit stars. That’s the rule, right? Well, maybe not. In fact the vast majority of planets could be floating freely through the Milky Way. Today we’re gonna talk about rogue planets. Sometimes planets just go... Read more...

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