

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

Jan 20, 2026 • 31min
Ask A Spaceman Ep. 264: Just How Weird is the Quantum Eraser?
Hosted by Dr. Paul M. Sutter. How does the double-slit experiment work? What does it teach us about reality and measurement if we try to mess with the experiment after it's already started? How does quantum complementarity guide us with how to think about it? I discuss these questions and more in today's Ask a Spaceman! Support the show: http://www.patreon.com/pmsutter All episodes: http://www.AskASpaceman.com Watch on YouTube: http://www.youtube.com/PaulMSutter Read a book: https://www.pmsutter.com/books Keep those questions about space, science, astronomy, astrophysics, physics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE! Big thanks to my top Patreon supporters this month: Justin G, Chris L, Alberto M, Duncan M, Corey D, Michael P, Naila, Sam R, Joshua, Scott M, Rob H, Scott M, Louis M, John W, Alexis, Gilbert M, Rob W, Jessica M, Jules R, Jim L, David S, Scott R, Heather, Mike S, Pete H, Steve S, Lisa R, Kevin B, Aileen G, Steven W, Deb A, Michael J, Phillip L, Steven B, Mark R, Alan B, Craig B, Richard K, Stephen J, Joe R, David P, Justin, Tracy F, Ella F, Thomas K, James C, Syamkumar M, Homer V, Mark D, Bruce A, Tim Z, Linda C, The Tired Jedi, Bob C, Stephen A, James R, Robert O, Allen E, Michael S, Reinaldo A, Sheryl, David W, Chris, Michael S, Erlend A, James D, Larry D, Karl W, Den K, Edward K, Craig M, Scott K, Vivek D, Barbara C, Brad, Azra K, Steve R, Koen G, and Scott N! 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.

Jan 19, 2026 • 31min
Astronomy Cast Ep. 779: Milankovitch Cycles
https://www.youtube.com/watch?v=rTFbrCIkrfU Streamed live on Jan 12, 2026. Hosted by: Fraser Cain (@frasercain ) and Dr. Pamela L. Gay (@CosmoQuest ) Humans live short lives, and from our perspective the seasons are something that come and go with perfect regularity. But astronomers know the terrible truth! And that there are cycles that slowly shift over tens of thousands of years, shifting the cycles and the Earth's climate. Today we'll talk about the Milankovich Cycles! The Earth's orbit, tilt, and other physical attributes aren't quite as constant as you might think! Come learn how long-term changes do and don't affect our climate. This show is supported through people like you on Patreon.com/AstronomyCast In this episode, we'd like to thank: Burry Gowen, Eric Lee, Jeanette Wink, Michael Purcell, Andrew Poelstra, David, David Rossetter, Ed, Gerhard Schwarzer, Jason Kwong, Joe McTee, Sergey Manouilov, Siggi Kemmler, Sergio 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.

Jan 18, 2026 • 6min
Travelers in the Night Eps. 847 & 848: Ultra Distant Comet & C.2024 E1 (Wierzchos)
Dr. Al Grauer hosts. Dr. Albert D. Grauer ( @Nmcanopus ) is an observational asteroid hunting astronomer. Dr. Grauer retired from the University of Arkansas at Little Rock in 2006. travelersinthenight.org From May 2025. Today's 2 topics: - My Catalina Sky Survey teammate Hannes Gröller was asteroid hunting in the constellation of Ursa Major with the University of Arizona 90 inch Bok telescope on Kitt Peak when he discovered a faint moving object surrounded by a tiny gas and dust cloud called a coma. May 19, 2028 comet C/2025 D1 (Groeller) reaches its closest point to the Sun some 14.1 times the Earth-Sun distance and thus sets the record for the comet which stays furtherest from the Sun.After rounding the Sun comet C/2025 D1 (Groeller) will head back into truly deep space perhaps never to return. - On March 3, 2024 my Catalina Sky Survey teammate Kacper Wierzchos was asteroid hunting with our 60 inch telescope on Mt. Lemmon, Arizona when he spotted a fuzzy object in the constellation of Draco. After Kacper reported his discovery to the Minor Planet Center, observers in Arizona, New Mexico, and Tenerife confirmed it to be a comet and it was given the name C/2024 E1 (Wierzchos). Kacper's discovery has a hyperbolic orbit indicating that after coming slightly closer to the Sun than the planet Venus on January 21, 2026 it will be ejected from the solar system never to return. 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.

Jan 17, 2026 • 7min
ASTROMAN - Lunar Eclipse
Dive into the wonders of the lunar eclipse! ASTROMAN breaks down the 2026 total "Blood Moon" in Asia, offering tips for skywatchers and the science behind the shadow. "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.

Jan 16, 2026 • 33min
EVSN - Astronomy Answers: What's That Light?
From January 7, 2026. In this episode, we're pleased to say we get to focus on science, as we bring you hot Jupiters, a tear-drop shaped Jupiter massed… something…? - and news of objects getting torn apart and other objects getting merged together as our universe lights up our night. 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.

Jan 15, 2026 • 55min
Actual Astronomy - OzSky With Clint Reading
Hosted by Chris Beckett & Shane Ludtke, two amateur astronomers in Saskatchewan. actualastronomy@gmail.com In this podcast (Episode 519) we talk with a special guest & long-time listener Clint Reading (from Nebraska, formerly from Idaho) about his astro-tourism trips to OzSky which is a biannual event for amateur astronomers from the northern hemisphere to have the opportunity to see the southern skies. We learn how to prepare for an astronomy trip to Australia, what to bring to get the most out of a week under the southern stars and how you can take advantage of these events. This is part of our New Years resolution to have more listener guests since there are so many of you doing astronomy activities that Shane and I can only dream of. Introduction: So welcome to the show Clint! We've been chatting for years so it's great to speak in person. Can you tell us a little about where you are and how you became interested in astronomy? How have you progressed through the hobby? Are you in any clubs? Are you visual, imaging, both? What equipment are you using? You've had some interesting adventures I recall you went to Lowell a couple years back to a public event, how was that? Main Show: Let's talk about your trip down south to OzSky (not to be confused with Ozzfest) So where is OzSky and what is it exactly? What is OzSky exactly? How is it organized? days/nights? Speakers? Cost? Other amateurs? How did you plan for the trip? What did you take for equipment and observing guides? What equipment do they provide? Day trips? Conclusion: Does anyone have anything to add? Thanks for joining us today Clint, we really appreciate it. Clear skies! 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.

Jan 14, 2026 • 15min
Cheap Astronomy - Dear CA Ep. 127: Mystery Physics
Hosted by Steve Nerlich. Well… Cheap Astronomy confirms some mysteries are still mysteries! Dear Cheap Astronomy – Is warp drive looking any more possible? Well, no, insofar as it looks about as possible as it ever did, which is to say, it's probably impossible, but at the same time, it's best to never say never. As we've covered before, the nature of space-time precludes the possibility of faster than light travel simply because light travels as fast as it is possible to travel in space-time. Dear Cheap Astronomy – What is X-17? X-17 is a mysterious and somewhat hypothetical particle. Somewhat hypothetical means there is a bit of evidence for its existence, although it's more a case of there being evidence of something unusual, rather than definitive evidence of a new particle that does something unusual. 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.

Jan 13, 2026 • 8min
Deep Astronomy - Discoveries of the Webb Space Telescope: Webb's First Deep Field
https://www.youtube.com/watch?v=WvdZpZuz-WQ Hosted by Tony Darnell. From Feb 13, 2025. The deep fields taken by the Hubble Space Telescope are now legendary. Astronomers used the most complicate and expensive instrument ever put into space to stare at nothing, a very risky move, but one that paid off. What happened when we did the same thing with the James Webb Space Telescope? 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.

Jan 12, 2026 • 37min
Astronomy Cast Ep. 778: Dyson Swarms
https://www.youtube.com/watch?v=cySk8O0iVjU Hosted by: Fraser Cain (@frasercain ) and Dr. Pamela L. Gay (@CosmoQuest ) Streamed live on Jan 5, 2026. Freeman Dyson asked a fascinating question. What would it look like if a civilization was using all the energy coming from their star? And what form would this take? This introduced the concept of a Dyson Sphere, or more realistically, a Dyson Swarm surrounding a star. But if you're skeptical about the concept, you're in good company. This show is supported through people like you on Patreon.com/AstronomyCast In this episode, we'd like to thank: Burry Gowen, Eric Lee, Jeanette Wink, Michael Purcell, Andrew Poelstra, David, David Rossetter, Ed, Gerhard Schwarzer, Jason Kwong, Joe McTee, Sergey Manouilov, Siggi Kemmler, Sergio Sancevero With special guest star Stella! 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.

Jan 11, 2026 • 6min
Travelers in the Night Eps. 845 & 846: Mighty Schmidt & Bright Nights
Dr. Al Grauer hosts. Dr. Albert D. Grauer ( @Nmcanopus ) is an observational asteroid hunting astronomer. Dr. Grauer retired from the University of Arkansas at Little Rock in 2006. travelersinthenight.org From April 2025. Today's 2 topics: - On a single February night my Catalina Sky Survey teammate Jacqui Fazekas reported the discovery of 5 Earth approaching objects using our small but mighty Schmidt telescope on Mt. Bigelow, Arizona.Rest assured that on any given night there are asteroid hunters on the look out for seriously dangerous space rocks. - One little known and infrequently observed phenomenon in the natural night sky are "bright nights" during which observers have reported being able to read a book when both the Sun and Moon are both well below the horizon. 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.


