Ep. 776: The Matter - Antimatter Dichotomy
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Streamed live on Dec 22, 2025. Shortly after the big bang there were almost exactly the same amounts of matter and antimatter in the Universe, but there was just enough of a difference that we live in a matter-dominated Universe. But it didn’t have to be that way! Explaining this mystery has been one of the great mysteries in astronomy, and today we’ll see if there’s been any progress! Why is the Universe the way it is? Specifically, why is it made mostly of matter? This is the question we'll look at today! This show is supported through people like you on...
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Ep. 775: The Hydrogen 21-cm Line
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Streamed live on Dec 15, 2025. Atomic hydrogen is the raw material for stars, but there’s a problem. It’s cold & dark, but it can do a very rare trick, releasing a photon in a very specific wavelength, known as the 21 centimeter line. And thanks to this wavelength astronomers have mapped out star forming regions across the Milky Way, the Universe and into the Dark Ages! This forbidden transition of Hydrogen has led to the mapping of galaxy rotation, a cool classroom application of quantum mechanics, and weirdly no Nobel prize. In this episode, Fraser and Pamela take a look at this...
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Ep. 774: How Does Bad Science Happen?
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Hosted by: Fraser Cain and Dr. Pamela L. Gay. Streamed live on Nov 8, 2025. [Editor's Note: Fraser says "Episode 773" at the head of the show. Not to worry, he was just confused. They recorded a few episodes out of sequence. I fixed the issue in the regular non-FullRaw episode.] Scientific expertise is under attack on all fronts with concerns coming from politicians and the public. While most of this is unwarranted and politically motivated, there can be germ of truth. Bad science does happen, but how? How is it that papers that very few believe still make it through peer review and to...
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Ep. 773: What Would You Do With $1 Billion For Astronomy?
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Hosted by: Fraser Cain and Dr. Pamela L. Gay. Streamed live on Nov 9, 2025. We are powerless fans of space exploration. But what if some fool gave us the authority and funding to make our space dreams a reality? Someone asked us what we’d do with a billion dollars. What missions? Which telescopes? But what if we had more? 100 Billion! A trillion! All the monies! You keep asking, and this week we answer you! Come hear what Fraser and Pamela would do if they were given complete control over $1billion that had to be used for astronomy. This show is supported through people like you...
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Ep. 772: 2025 Gift Guide
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Hosted by: Fraser Cain and Dr. Pamela L. Gay. Streamed live on Nov 9, 2025. It’s time once again for our annual gift giving guide. We’ve got recommendations for books, movies, TV shows, games and of course astronomy gear to satisfy the space nerds in your family. The Christmas season is almost upon us, and with it comes excuses to inject science into the lives of those you love... or ask for them to give you that book, lens, or art print you already know you'll love. In this episode, Fraser and Pamela share the things they think would make good gifts for nerds like us. This...
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Ep. 771: Comet Tails
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Streamed live on Nov 8, 2025. With the arrival of the comet 3I/Atlas (Asteroid Terrestrial-impact Last Alert System), the world is getting a crash course in comets, their behavior, and of course their tails. Today we’re going to talk about comets and their tails, why they exist, how they grow, why they can be different colors and how they can be sometimes point AT the Sun. Comets are one of the most animated and ephemeral targets for astronomy. From night to night they can change in shape and color, and every nuance tells us something. In this episode, we decode blue tails, green...
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Ep. 770: The Ethics of Mars Exploration
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Streamed live on Nov 3, 2025. Hosted by: Fraser Cain and Dr. Pamela L. Gay. It is arguable that humanity now has the technological ability to live on Mars. It would be done at enormous expense and sacrifice, and there are some tricky problems that we haven’t solved yet. Although we could live on Mars, should we? There is a famous quote from Jurassic Park: "Your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should." This concept is played out across the sciences, and in planetary exploration, it requires us to ask, all because we can launch...
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Ep. 769: Little Red Dots
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Streamed live on Oct 20, 2025. New instruments bring new mysteries, and when James Webb came on line it uncovered a collection of strange, compact, bright objects shifted deeply into the red end of the spectrum. These were dubbed “Little red dots” or LRDs. And the astronomical community continues to puzzle over what they are. When JWST first peered into the distant past, it discovered the early universe had a rash of little red dots. Their existence just 450 million years after the big bang meant either galaxies were forming way faster than anyone predicted, or something unimagined had...
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Ep. 768: Comets' Unpredictability
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Streamed live on Oct 13, 2025. So it’s been decades since we’ve seen a bright comet in the sky. And actually there was a pair — Hale-Bopp and Hyakutake. And then, silence! And unmet promises by the Universe to give us a bright comet. Comets are unpredictable, and they arrive precisely when they intend to. Is it time again for a bright comet? If you asked us in January if 2025 was going to have any outstanding comets would fly through the Solar System, we would have (and we did) say "no." And we were wrong. Comets are fickle, unpredictable, and like to do exactly what we didn't predict....
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Ep. 767: Black Holes in Extreme Circumstances
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Hosted by: Fraser Cain and Dr. Pamela L. Gay Streamed live on Oct 6, 2025. You can only describe a black hole by its mass and its spin. And maybe it’s charge. But allow us to propose a new criteria: the personal experience. Some black holes have seen things… Experienced the laws of physics at their most extreme. And today we’ll tell their stories. The more of the sky we observe, the more bizarre situations we find black holes in. Let's explore! This show is supported through people like you on Patreon.com/AstronomyCast In this episode, we'd like to thank: Andrew Poelstra,...
info_outlineStreamed live Feb 20, 2025.
I’m sure you’ve heard the news, asteroid 2024 YR4 has a tiny chance of hitting Earth in 2032. How do astronomers discover these dangerous asteroids, measure their future impact risk and track the changes over time? When should we panic? New asteroids are found every day, and every day we learn that those asteroids don't have any murderous intentions. But how do we learn that? In this episode we dig into asteroid orbital determination.
Hosted by: Fraser Cain and Dr. Pamela L. Gay
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Thanks to: Andrew Poelstra, BogieNet, Brian Cagle, David, David Truog, Ed, Gerhard, Schwarzer, Jeanette Wink, Siggi Kemmler, Stephen Veit