We’re familiar with regular binary stars. Two stars orbiting each other. Simple. Of course, the Universe has come up with every combination of things orbiting other things. And this week we look at the extreme version of this.
Ep. 570: Discovering Comets
Discovering comets is one of the fields that amateurs can still make a regular contribution to astronomy. But more and more telescopes are getting found by spacecraft, automated systems and machine learning. This week, we’ll talk about how comets are discovered and how you can get your name on one.
Ep. 566: When Comets Fall Apart
As everyone knows, the Universe owes us a bright comet. There have been a lot of promising candidates, but in the end, they always fail to live up to our expectations. Comets keep on breaking up with us.
Ep. 565: When Worlds Collide
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.
Ep. 560: Betelgeuse
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.
Ep. 559: The Surface of the Sun
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.
Ep. 556: Multi Messenger Astronomy
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.
Ep. 554: Big Telescope Controversy in Hawai’i
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.
Ep. 546: Weird Issues: Planetary Migration
Before we discovered other planets, our Solar System seemed like a perfectly reasonable template for everywhere. But now we see massive planets close to their stars, which leads you to the question, how does it all get there. Do the planets form in place or do they migrate around?
Ep. 545: Weird Issues: Are comets asteroids or are asteroids comets?
Things used to be so simple. Comets were snowballs from the outer Solar System, and asteroids were rocks from the inner Solar System. But now everything’s all shades of grey. Astronomers have found asteroids that behave like comets and comets that behave like asteroids.
Ep. 544: Weird Issues: Biosignatures
Once again, another place where the Universe is going to make this difficult for us. Proving, once and for all that there’s alien life on another world. It should be straightforward, look for biosignatures, but it looks like there are natural sources that could explain almost any chemical we could hope to search for.
Ep. 540: Weird Issues: How Do (or Don’t) Planets Form?
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.
Ep. 539: Weird Issues: Why We Don’t Know the Age of Saturn’s Rings
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.
Ep. 538: Asteroids: Rubble piles of the Solar System
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.
Ep. 534: Modern South African Astronomy
Last week we talked about some ancient south African astronomy, so this week we'll talk about the state of modern astronomy in the southern part of Africa, which happens to be a great place with nice dark skies and a great view into the heart of the galaxy. In this...
Ep. 533: Indigenous South African Astronomy
Let's move to another continent this week, and look at the astronomy that was going on in southern Africa in ancient times. In this episode we mentioned donations and tours. Click to learn more! Download MP3| Download Raw Show with Q&A| Show Notes | Jump to...
Ep. 532: Modern Astronomy of Australia
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. In this episode we mentioned...
Ep. 529: Astronomy of the Andes – Then and Now Pt. 1
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...
Ep. 528: Modern Astronomy of the American Southwest
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?
Ep. 527: Ancient Astronomy of the American Southwest
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. In this episode we mentioned...
Ep. 526: Event Horizon Telescope and the Black Hole at M87
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.
Ep. 525: 100 Years of the International Astronomical Union
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.
Ep. 523: Judging Age & Origins, Pt. 2 Across the Solar System
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?
Bonus Episode: Dust with Dr. Paul Sutter
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.
Ep. 522: Judging Age & Origins, part 1 – Earth Rocks
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.