541: Weird Issues: Expansion Rate of the Universe Astronomy Cast 541: Weird Issues: Expansion Rate of the Universe by Fraser Cain & Dr. Pamela Gay Just when the Universe was starting to make sense, the cosmos throws a curveball at us. Astronomers have been trying to accurately measure the expansion rate of the Universe as far back as Hubble. It's been tough to nail down, and now astronomers are starting to figure out why.
Oct 07, 2019•29 min
540: Weird Issues: How Do (or Don't) Planets Form? Astronomy Cast 540: Weird Issues: How Do (or Don't) Planets Form? by Fraser Cain & Dr. Pamela Gay As astronomers started to discover planets orbiting other stars, they immediately realized that their expectations would need to be tossed out. Hot jupiters? Pulsars with planets? We're now decades into this task, and the Universe is continuing to surprise us.
Sep 30, 2019•31 min•Season 1Ep. 540
539: Weird Issues: Why We Don't Know the Age of Saturn's Rings Astronomy Cast 539: Weird Issues: Why We Don't Know the Age of Saturn's Rings by Fraser Cain & Dr. Pamela Gay How old are Saturn's rings? They could be brand new, or they could be as ancient as the Solar System itself. Planetary scientists thought they knew the answer thanks to new data from Cassini, but new ideas are calling even that into question.
Sep 23, 2019•30 min•Season 1Ep. 539
538: Asteroids: Rubble piles of the Solar System Astronomy Cast 538: Asteroids: Rubble piles of the Solar System by Fraser Cain & Dr. Pamela Gay Thanks to all the work from Hayabusa 2 and OSIRIS-REx, astronomers are getting a much better look at the smaller asteroids in the Solar System. It turns out, they're piles of rubble... but fascinating piles of rubble. Let's talk about what we've learned so far.
Sep 16, 2019•31 min•Season 1Ep. 538
537: Reusable Rocket Revolution Astronomy Cast 537: Reusable Rocket Revolution by Fraser Cain & Dr. Pamela Gay We took a hiatus this summer, but SpaceX sure didn’t, with the tests of the Starhopper prototype. Today we’re going to talk about the revolution in reusable rocketry and quest to build a fully reusable two-stage rocket.
Sep 09, 2019•38 min•Season 1Ep. 537
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Aug 10, 2019•54 sec
Astronomy Cast will be on hiatus for July and August. Don't worry, we'll be back in September, and we might just have surprises for you all along this summer! Don't forget you can still catch Pamela with Daily Space, rocket launches and specials on , and you can find all the space news and videos from Fraser at ! We usually record Astronomy Cast every Friday at 3:00 pm EDT / 12:00 pm PDT / 19:00 UTC. You can watch us live on here on , or the .
Jul 01, 2019•2 min
536: Everyday Relativity Astronomy Cast 536: Everyday Relativity by Fraser Cain & Dr. Pamela Gay Relativity is used in more day to day situations than you may realize. In this episode, we will count (some of) the ways. This episode is brought to you live from the All-Stars Star Party in Indian Wells, California.
Jul 01, 2019•35 min•Season 1Ep. 536
535: Astronomy-Related Things To Do This Summer Astronomy Cast 535: Astronomy-Related Things To Do This Summer by Fraser Cain & Dr. Pamela Gay It's summertime, and time for our annual Astronomy Cast hiatus. But that doesn't mean that the astronomy adventure has to end. Today we'll give you some tips and tricks for astronomy summer adventures.
Jun 24, 2019•34 min•Season 1Ep. 535
534: Modern South African Astronomy Astronomy Cast 534: Modern South African Astronomy by Fraser Cain & Dr. Pamela Gay You know the drill now. Last week we talked about ancient south African astronomy, and so this week we'll talk about the modern state of astronomy in the southern part of Africa, which happens to be a great place with nice dark skies and a perfect view into the heart of the galaxy.
Jun 17, 2019•34 min•Season 1Ep. 534
533: Indigenous South African Astronomy Astronomy Cast 533: Indigenous South African Astronomy by Fraser Cain & Dr. Pamela Gay Let's move to another continent this week, and look at the astronomy that was going on in southern Africa in ancient times.
Jun 10, 2019•34 min•Season 1Ep. 533
532: Modern Astronomy of Australia Astronomy Cast 532: Modern Astronomy of Australia by Fraser Cain & Dr. Pamela Gay Last week we talked about how well the indigenous Australians followed the night sky. Well, it turns out, Australia is still an amazing place for astronomy. There are so many powerful observatories in Australia, and even more in the works.
Jun 03, 2019•35 min•Season 1Ep. 532
531: Australian Indigenous Astronomy Astronomy Cast 531: Australian Indigenous Astronomy by Fraser Cain & Dr. Pamela Gay South America, especially the Atacama Desert in Chile has become one of the best places in the world to put a telescope. It's dry, high, and the nights are clear. Today we'll talk about the monster telescopes already in operation in this region, and the big ones coming soon.
May 27, 2019•31 min•Season 1Ep. 531
530: Astronomy of the Andes - Then and Now Pt. 2 Astronomy Cast 530: Astronomy of the Andes - Then and Now Pt. 2 by Fraser Cain & Dr. Pamela Gay South America, especially the Atacama Desert in Chile has become one of the best places in the world to put a telescope. It's dry, high, and the nights are clear. Today we'll talk about the monster telescopes already in operation in this region, and the big ones coming soon.
May 12, 2019•31 min•Season 1Ep. 530
529: Astronomy of the Andes - Then and Now Pt. 1 Astronomy Cast 529: Astronomy of the Andes - Then and Now Pt. 1 by Fraser Cain & Dr. Pamela Gay The Andes mountains in South America are a hotspot of astronomy today, but ancient peoples knew it was a great place for astronomy and lived their lives in tune with the night sky. Today we'll learn all about what they knew, and how they mapped the movements of the stars and planets.
May 06, 2019•29 min•Season 1Ep. 529
528: Modern Astronomy of the American Southwest Astronomy Cast 528: Modern Astronomy of the American Southwest by Fraser Cain & Dr. Pamela Gay Last week we talked about the ancient astronomy of the American Southwest. But this is actually Pamela's stomping grounds, and she's spent many a night perched atop mountains in this region staring in the night sky with gigantic telescopes. How does astronomy get done in this region today?
Apr 29, 2019•35 min•Season 1Ep. 528
527: Ancient Astronomy of the American Southwest Astronomy Cast 527: Ancient Astronomy of the American Southwest by Fraser Cain & Dr. Pamela Gay Ancient peoples had no light pollution, and they knew the night skies very well. In fact, they depends on them to know when to plant and when to harvest. Today Pamela talks about the archeoastronomical sites of the American Southwest.
Apr 22, 2019•34 min•Season 1Ep. 527
526: Event Horizon Telescope and the Black Hole at M87 Astronomy Cast 526: Event Horizon Telescope and the Black Hole at M87 by Fraser Cain & Dr. Pamela Gay Today, of course, we're going to talk about the announcement from the Event Horizon Telescope and the first photograph of a black hole's event horizon.
Apr 15, 2019•35 min•Season 1Ep. 526
525: 100 Years of the International Astronomical Union Astronomy Cast 525: 100 Years of the International Astronomical Union by Fraser Cain & Dr. Pamela Gay Even though they might be scattered around our planet, astronomers have way to come together to work out issues that face their entire field of study. It's called the International Astronomical Union, and they're the ones who work out the new names for stars, and sometimes de-planet beloved Kuiper Belt Objects.
Apr 08, 2019•36 min•Season 1Ep. 525
524: Judging Age & Origins, part 3 - Beyond Our System Astronomy Cast 524: Judging Age & Origins, part 3 - Beyond Our System by Fraser Cain & Dr. Pamela Gay We learned how to figure out the ages of objects in the Solar System, now we push out into the deeper Universe. What about stars, galaxies, and even the Universe itself? How old is it? This episode is part 3 of a series.
Apr 01, 2019•34 min•Season 1Ep. 524
523: Judging Age & Origins, Pt. 2 Across the Solar System Astronomy Cast 523: Judging Age & Origins, Pt. 2 Across the Solar System by Fraser Cain & Dr. Pamela Gay Today we push our aging curiosity out into the Solar System to ask that simple question: how old is it and how do we know? What techniques do astronomers use to age various objects and regions in the Solar System? This is part two of a series.
Mar 25, 2019•33 min•Season 1Ep. 523
522: Judging Age & Origins, part 1 - Earth Rocks Astronomy Cast 522: Judging Age & Origins, part 1 - Earth Rocks by Fraser Cain & Dr. Pamela Gay People always want to know how old everything is. And more specifically, they want to know how we know how old everything is. Well, here at Astronomy Cast, it's our job to tell you now only what we know, but how we know what we know. And today we'll begin a series on how we know how old everything is.
Mar 18, 2019•32 min•Season 1Ep. 522
Bonus: Dust with Dr. Paul Sutter Astronomy Cast Bonus: Dust with Dr. Paul Sutter by Fraser Cain & Dr. Pamela Gay Recorded during the Astrotour to Costa Rica, Fraser talks to Dr. Paul Matt Sutter about the nature of dust and BICEP 2's claim of discovering primordial gravitational waves.
Mar 17, 2019•21 min
521: The Deep Space Network Astronomy Cast 521: The Deep Space Network by Fraser Cain & Dr. Pamela Gay We always focus on the missions, but there's an important glue that holds the whole system together. The Deep Space Network. Today we're going to talk about how this system works and how it communicates with all the spacecraft out there in the Solar System.
Mar 11, 2019•34 min•Season 1Ep. 521
520: Transients: What They Are and Why They Matter, Part 2 Astronomy Cast 520: Transients: What They Are and Why They Matter, Part 2 by Fraser Cain & Dr. Pamela Gay
Mar 01, 2019•32 min•Season 1Ep. 520
519: Transients: What They Are and Why They Matter Astronomy Cast 519: Transients: What They Are and Why They Matter by Fraser Cain & Dr. Pamela Gay
Feb 25, 2019•30 min•Season 1Ep. 519
518: When the Universe tried to Declare War Astronomy Cast 518: When the Universe tried to Declare War by Fraser Cain & Dr. Pamela Gay
Feb 18, 2019•30 min•Season 1Ep. 518
517: Fritz Zwicky and the Zwicky Transient Facility Astronomy Cast 517: Fritz Zwicky and the Zwicky Transient Facility by Fraser Cain & Dr. Pamela Gay
Feb 11, 2019•30 min•Season 1Ep. 517
516: Polar Vortices Astronomy Cast 516: Polar Vortices by Fraser Cain & Dr. Pamela Gay
Feb 04, 2019•29 min•Season 1Ep. 516
515: Space Radiation Astronomy Cast 515: Space Radiation by Fraser Cain & Dr. Pamela Gay
Jan 28, 2019•30 min•Season 1Ep. 515