

The 365 Days of Astronomy
365DaysOfAstronomy.org
The 365 Days of Astronomy podcast launched in 2009 as part of the International Year of Astronomy. This community podcast continues to bring you day after day of content across the years. Everyday, a new voice, helping you see the universe we share in a new way. This show is managed by Avivah Yamani, edited by Richard Drumm. This podcast is funded through Patreon.com/CosmoQuestX and produced out of the Planetary Science Institute.
Episodes
Mentioned books

Dec 26, 2025 • 22min
EVSN - Six-Exoplanet System in Resonance, Challenges Formation Theories
From January 27, 2021. It's a day ending in 'y', and planetary formation theories are once again being challenged. This time the challenge comes from a six-planet system with five planets in resonance. Plus a cloudless Jupiter, TRAPPIST-1, volcanoes, and some science of the weird. We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 25, 2025 • 20min
Space Stories - Second Landing
Hosted by Dr. Pamela Gay. A gentle fancy for the Christmas Season—an oft-told tale with a wistful twistful of Something that left the Earth with a wing and a prayer. Earlier today, I had the stark realization that at the core of many Christmas stories is a core of sorrow or longing that must somehow be transformed into joy. Scrouge must learn charity. Ralphie longs for a bb gun and is betrayed by his joy. George is on the brink of suicide when his Guardian Angel intercedes. John McClane just needs to keep his wife alive (yes, Die Hard is a Christmas movie). Over and over, the holiday spirit can only enter on the wings of struggle. This realization came to me as I looked for an old school (aka public domain) science fiction story to narrate for tomorrow's episode of 365 Days of Astronomy. The first story I came across (which I'll personally share tomorrow), was Arthur C Clarke's, "The Star" and it was too dark for that family-friendly podcast. Instead, I read "Second Landing," by Floyd Wallace. This story originally appeared in Amazing Science Fiction Stories. Read it here: https://www.gutenberg.org/cache/epub/24958/pg24958-images.html Written in 1960 by Floyd L. Wallace, this story is weirdly timeless and felt utterly necessary for this moment. Aliens learn of Earth from our broadcasts, and they fear we are on the verge of destroying ourselves with the bomb. To say more would be to reveal the plot. I invite you to listen here and find hope in a world of too much darkness. Merry Christmas. We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 24, 2025 • 6min
Space Stories - Solstice: When the Sun Stands Still
Hosted by our Director, Avivah Yamani! What does "solstice" really mean? In this episode, we unpack the Sun's yearly turning point, the seasonal flip between hemispheres, and the ancient sky-architecture of Stonehenge, from June solstice sunrise to December solstice sunset. We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 23, 2025 • 8min
Deep Astronomy - The Largest Galaxy in the Universe: IC 1101
https://www.youtube.com/watch?v=UE8yHySiJ4A Hosted by Tony Darnell. From Sep 21, 2012. This video was done by request from a Space Fan. Hope it's what you had in mind. IC 1101 is over one billion light years away in the constellation Virgo, just over the border from Serpens. https://en.wikipedia.org/wiki/IC_1101 We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 22, 2025 • 35min
Astronomy Cast Ep. 775: The Hydrogen 21-cm Line
https://www.youtube.com/watch?v=2uvcumUc6Gc Hosted by: Fraser Cain ( @frasercain ) and Dr. Pamela L. Gay ( @CosmoQuest ) 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 line's out-of-proportion awesomeness! This show is supported through people like you on Patreon.com/AstronomyCast In this episode, we'd like to thank: Andrew Poelstra, BogieNet, Brian Cagle, Burry Gowen, David, David Rossetter, Ed, Gerhard Schwarzer, Jason Kwong, Jeanette Wink, Michael Purcell, Sergey Manouilov, Siggi Kemmler, Sérgio Sancevero We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 21, 2025 • 6min
Travelers in the Night Eps. 359E & 360E: One in 100,000 & Finding Spacerocks
The podcast delves into the fascinating topic of Apophis, a massive asteroid once feared to be on a collision course with Earth. Initial concerns have been laid to rest, indicating a mere one in 100,000 chance of impact over the next century. The discussion shifts to the thrill of hunting for meteorites, offering tips on ideal search locations and essential tools. Listeners learn about the unique characteristics that define meteorites and the excitement of holding a piece of ancient space rock in their hands.

Dec 20, 2025 • 6min
Astroman - Tips for Effective Science Communication
Episode 12. "ASTROMAN: the Dark Sky Guardian" is a podcast channel that aims to explore popular science in multiple disciplines and research on interdisciplinary approaches, such as sustainability, dark-sky protection, astrophotography, space exploration, astronomy innovation, inclusive science communication, and STEAM Education by integrating science and arts. Exodus CL Sit, also known as the ASTROMAN, is a transmedia astronomy educator, popular science author, STEAM educator, and science communicator in Hong Kong. He is recently the National Astronomy Education Coordinator (Chair of Hong Kong, China) of the International Astronomical Union and President of Starrix. He was also an International Committee Member of the Dark Sky International, regularly organizing public lectures at the Hong Kong Space Museum and the Hong Kong Science Museum. He was also the author of a popular science book "Decoding the Starry Night: A Guide to Stargazing and Astrophotography". We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 19, 2025 • 9min
EVSN - Asteroid Destruction, Brown Dwarf Formation & Getting Science From Dust
Discover how the YORP effect might spin asteroids to their doom in dying star systems. Learn about the differences in formation between giant planets and brown dwarfs, and how the latter show eccentric orbits that suggest a stellar origin. Plus, delve into a groundbreaking technique that analyzes lunar and planetary dust at atomic levels, unlocking secrets of water and helium. Tune in for these cosmic mysteries and more!

Dec 18, 2025 • 50min
Actual Astronomy - PiFinder
Hosted by Chris Beckett & Shane Ludtke, two amateur astronomers in Saskatchewan. actualastronomy@gmail.com Today we have a guest joining us, Richard Wolf-Jacobson who is the founder of BB Labs/ PiFinder which is a new type of finder device. https://www.pifinder.io/ Before we get going Richard, can you tell us about where you are / observe / how you got started in Astronomy, what your interests are and what equipment you use? * What is a Pi Finder? * How does it work? / How do you set it up? * Do you need to attach anything to your AltAz or Dec Axis? * What is plate solving..isn't that just for imagers? * How accurate is it? * What camera is in the device? Can someone do anything with the images? Do they get exported out to one's phone? * How did you come up with the PiFinder * I see it is Open Source - what makes it open source? How can people modify it? Can someone roll their own? * What databases are in there? Can someone add their own? Can it interface with SkySafari or other softwares? * What formats does it come in or is it one size fits all? * Can one change from a back view to a side view to take it from a refractor to a dob. *Does it interface with Smart Phone? * How does it perform in the cold? * How small a scope can it go onto? * What are your future plans? We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.

Dec 17, 2025 • 7min
UNAWE Space Scoop - What's the Shape of a Supernova?
https://spacescoop.org/en/scoops/2528/whats-the-shape-of-a-supernova/ Rewritten & recorded by your editor, Richard Drumm. When you imagine an explosion in space, a supernova is usually what first comes to mind. But astronomers are still quite puzzled by some of the details of these cosmic fireworks. The typical supernova we often picture is really the end of a massive star's life. And a very dramatic ending at that! During its existence, a star keeps its spherical shape through a very delicate balance between: - the outward pressure created by the core's nuclear heat, what we call the radiation pressure, and - the gravity that compresses the star toward its center of mass. We call this balance a state of hydrostatic equilibrium. We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs. Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too! Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations. Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.


