Astronomy Cast

565: When Worlds Collide Astronomy Cast 565: When Worlds Collide by Fraser Cain & Dr. Pamela Gay So much of our Solar System has been shaped by enormous collisions early on in our history. Seriously, the nature of every planet in the Solar System has some evidence of massive impacts during some point in its history.

564: Mini Moons Astronomy Cast 564: Mini Moons by Fraser Cain & Dr. Pamela Gay Last month astronomers announced that they had detected a tiny asteroid that had been captured by the Earth's gravity well and had been sharing our orbit for a few years. Today, let's talk about the smallest moons in the Solar System.

563: White Dwarf Mergers Astronomy Cast 563: White Dwarf Mergers by Fraser Cain & Dr. Pamela Gay White dwarfs are usually about 60% the mass of the Sun, so it was a bit of a surprise when astronomers found one that was almost exactly twice that. What happens when white dwarfs merge?

562: Dealing with COVID-19 and the Changes it will Bring Astronomy Cast 562: Dealing with COVID-19 and the Changes it will Bring by Fraser Cain & Dr. Pamela Gay Pamela and Fraser discuss the implications of COVID-19 and it's changes on the world, and what we all can do during this time.  

561: Remembering Katherine Johnson Astronomy Cast 561: Remembering Katherine Johnson by Fraser Cain & Dr. Pamela Gay We lost a bright star here on planet Earth last week. NASA mathematician Katherine Johnson passed away at the age of 101, after an incredible career of helping humans land on the Moon. If you saw the movie Hidden Figures, you'll know what I'm talking about.

560: Betelgeuse Astronomy Cast 560: Betelgeuse by Fraser Cain & Dr. Pamela Gay You might be surprised to hear that we've never done an episode of Astronomy Cast featuring Betelgeuse. Well, good news, this is that episode. Let's talk about the star, why it might be dimming, and what could happen if it explodes as a supernova.

559: The Surface of the Sun Astronomy Cast 559: The Surface of the Sun by Fraser Cain & Dr. Pamela Gay A brand new telescope has completed on Maui's Haleakala, and it has just one job: to watch the Sun in unprecedented detail. It's called the Daniel K. Inouye telescope, and the engineering involved to get this telescope operational are matched by the incredible resolution of its first images.

558: Supernova SN 2006gy Astronomy Cast 558: Supernova SN 2006gy by Fraser Cain & Dr. Pamela Gay We've been following this story for more than a decade, so it's great to finally have an answer to the question, why was supernova 2006gy so insanely bright? Astronomers originally thought it was an example of a supermassive star exploding, but new evidence provides an even more fascinating answer.

557: Red Dwarfs: Friend or Foe Astronomy Cast 557: Red Dwarfs: Friend or Foe by Fraser Cain & Dr. Pamela Gay On the one hand, red dwarfs are the longest lived stars in the Universe, the perfect place for life to hang out for trillions of years. On the other hand, they're tempestuous little balls of plasma, hurling out catastrophic flares that could wipe away life. Are they good or bad places to live?

556: Multi Messenger Astronomy Astronomy Cast 556: Multi Messenger Astronomy by Fraser Cain & Dr. Pamela Gay For the longest time astronomers could only study the skies with telescopes. But then new techniques and technologies were developed to help us see in different wavelengths. Now astronomers can study objects in both visible light, neutrinos, gravitational waves and more. The era of multi-messenger astronomy is here.

555: Satellite Constellations and the Future of Astronomy Astronomy Cast 555: Satellite Constellations and the Future of Astronomy by Fraser Cain & Dr. Pamela Gay The other big issue at the AAS was the challenge that astronomy is going to face from all the new satellite constellations coming shortly. There are already 180 Starlinks in orbit, and thousands more are coming, not to mention the other constellations in the works. What will be the impact on astronomy, and what can we do about it?

554: Big Telescope Controversy in Hawai'i Astronomy Cast 554: Big Telescope Controversy in Hawai'i by Fraser Cain & Dr. Pamela Gay This week we're live at the American Astronomical Society's 235th meeting in Honolulu, Hawai'i. We learned about new planets, black holes and star formation, but the big issue hanging over the whole conference is the protests and politics over the new Thirty Meter Telescope due for construction on Mauna Kea.  

553: What To Look Forward To In 2020 Astronomy Cast 553: What To Look Forward To In 2020 by Fraser Cain & Dr. Pamela Gay It's hard to believe it, but we survived another trip around the Sun. Now it's time to take the whole journey all over again, but with new news. Let's take a look at some of the space and astronomy stories we're looking forward to in 2020.

552: Boyajian's star (and other strange stars) Astronomy Cast 552: Boyajian's star (and other strange stars) by Fraser Cain & Dr. Pamela Gay Huge surveys of the sky are finding more and more planets, stars and galaxies. But they're also turning up strange objects astronomers have never seen before, like Boyajian's star. Today we're going to talk about some unusual objects astronomers have discovered, and why this number is only going to go way way up.

Hi everyone, Producer Susie here. This weekend, December 21-23, 2019, we will be having our CosmoQuest Hangoutathon.  For 40 straight hours, our team will be bringing you guests, science and fun live on our channel. We are raising money to pay for our team to continue to bring you science, and for us to continue our citizen science programs, like the extremely successful Bennu Mappers from this past year, where over 3500 of you wonderful volunteers mapped over 14 million rocks on the asteroid Bennu, looking for a safe place for the OSIRIS-REx mission to grab samples to return to earth.  We want to keep doing projects like this - and we need your help to continue doing the science.  Please join us at starting 9am EST / 6am PST / 1400UTC. If you can’t tune in live, you can catch the replays on Twitch, and we’ll be trying our best to archive all of the content on YouTube after this weekend. We’re accepting donations at As part of the Planetary Science Institute, we are a 501c3 non-profit, so all of your donati

551: Missing Epochs - Observing before the CMBR Astronomy Cast 551: Missing Epochs - Observing before the CMBR by Fraser Cain & Dr. Pamela Gay The Cosmic Microwave Background Radiation is the earliest moment in the Universe that we can see with our telescopes, just a few hundred thousand years after the Big Bang itself. What will it take for us to be able to fill in the missing gap? To see closer to the beginning of time itself?

550: Missing Epochs - Observing the Cosmic Dark Ages Astronomy Cast 550: Missing Epochs - Observing the Cosmic Dark Ages by Fraser Cain & Dr. Pamela Gay Powerful observatories like Hubble and the Very Large Telescope have pushed our vision billions of light-years into the Universe, allowing us to see further and further back in time. But there are regions which we still haven't seen: the Cosmic Dark Ages. What's it going to take to observe some of these earliest moments in the Universe?

549: Stellar nucleosynthesis revisited: In and on and around dead stars Astronomy Cast 549: Stellar nucleosynthesis revisited: In and on and around dead stars by Fraser Cain & Dr. Pamela Gay Last week we gave you an update on the formation of elements from the Big Bang and in main sequence stars like the Sun. This week, we wrap up with a bang, talking about the death of the most massive stars and how they seed the Universe with heavier elements.

548: Stellar nucleosynthesis revisited: In stellar cores & atmospheres Astronomy Cast 548: Stellar nucleosynthesis revisited: In stellar cores & atmospheres by Fraser Cain & Dr. Pamela Gay The Universe started out with hydrogen and helium and a few other elements, but all around us, there are other, more proton-rich elements. We believe these heavier elements formed in stars, but which stars? And at what points in their lives? Today we'll update our knowledge with the latest science.

547: Why Astronomy Still Needs Humans Astronomy Cast 547: Why Astronomy Still Needs Humans by Fraser Cain & Dr. Pamela Gay Few sciences have been able to take advantage of the power of computers like astronomy. But with all this computing power, you might be surprised to learn how important a role humans still play in this science.