Ep. 722: Weather on Exoplanets

Ep. 722: Weather on Exoplanets

Here’s a familiar question: how’s the weather? We’re familiar with the weather on Earth and telescopes and missions are watching the weather on other planets in the Solar System. But for the first time in history, astronomers can now answer that question for...

Ep 721: Free-Floating Planets

Ep 721: Free-Floating Planets

Most of the exoplanets we’ve found are around stars, where they belong. But a few have been found free-floating in interstellar space. The evidence is growing that there are a lot of them out there, maybe even more than planets with stars. How do they form and how can...

Ep. 714: Orbital Resonances

Ep. 714: Orbital Resonances

Several of the planets and moons in the Solar System are in orbital resonance, orbiting in a geometric lockstep. And not just the Solar System, astronomers have found the same resonances in other star systems.

Ep. 705: Water Worlds – Looking for Life Beyond Earth

Ep. 705: Water Worlds – Looking for Life Beyond Earth

Wherever we find liquid water on Earth, we find life, so it makes sense to search for water across the Universe, and hopefully we can find evidence of life. But what about worlds which are completely covered in water, oceans hundreds of kilometers deep. Can there be too much water?

Ep. 676: Other Things with Rings

Ep. 676: Other Things with Rings

We’ve spent a lot of time gushing about Saturn’s rings, but there are other places with ring systems. And not just Jupiter and the ice giants, but asteroids, dwarf planets, centaurs and even exoplanets. Today we’ll gush about them.

Ep. 657: Astronomical Naming Schemes

Ep. 657: Astronomical Naming Schemes

Space is a big place, with a lot of galaxies, stars, planets and moons, and that means a lot of names. How do astronomers name stuff, like comets, asteroids, exoplanets, craters?

Ep. 633: Weirdly Habitable Places

Ep. 633: Weirdly Habitable Places

We’ve always assumed that habitable planets would need to be like Earth; a terrestrial planet orbiting a sunlike star. But now astronomers have been discovering planets in the habitable zone around very much non-sunlike stars. What strange places could be habitable?

Ep. 625: End of the Year Review

Ep. 625: End of the Year Review

We’ve reached the end of 2021, and this is the last episode of the year. Let’s look back at the big space events of the last year and talk about what we’re looking forward to in 2022.

Ep. 618: Ice Giants

Ep. 618: Ice Giants

We’re learning more and more about the outer planets of the Solar System. Uranus and Neptune are ice giants, filled with water and other volatiles that we’d consider ice if it was here on Earth. What’s inside these worlds, and what could we expect to find across the Milky Way?

Ep. 610: What is Required to Confirm Alien Life: Non-sentient Edition

Ep. 610: What is Required to Confirm Alien Life: Non-sentient Edition

Are we alone in the Universe? It’s one of the biggest scientific questions we can possibly ask. And yet, with rovers on Mars, missions planned to visit Europa and Ganymede. Powerful telescopes able to detect the atmospheres of exoplanets, we’re closer than ever to finding out the answer.

Ep. 600: Looking Ahead

Ep. 600: Looking Ahead

Today, we gaze into the future of space and astronomy. What upcoming missions and events are we excited about?

Ep. 595: Planet Hunting (Updated)

Ep. 595: Planet Hunting (Updated)

This is going to be another one of those evergreen topics, where we come back to again and again. Finding planets. Every time we talk about this now, it seems like we’ve gained thousands of new planets. Well buckle up, new techniques will grow that by tens of thousands and even millions.

Ep. 585: Super Earths, Mini-Neptunes, Gas Dwarfs

Ep. 585: Super Earths, Mini-Neptunes, Gas Dwarfs

As astronomers are finding even more new extrasolar planets, they’re starting to discover entirely new categories. There are classes of planets out there that we just don’t have any analog here in the Solar System. Let’s talk about them.

Ep. 573: Exoplanet Atmospheres

Ep. 573: Exoplanet Atmospheres

Not only have astronomers discovered thousands of exoplanets, but they’re even starting to study the atmospheres of worlds thousands of light-years away. What can we learn about these other worlds, and maybe even signs of life.

Ep. 572: Twists in Planet Formation

Ep. 572: Twists in Planet Formation

We’re all looking forward to the next generation of exoplanetary research, where we get to see pictures of planets directly. But astronomers are already making great strides in directly observing newly forming planets, helping us understand how our Solar System might have formed.

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. 540: Weird Issues: How Do (or Don’t) Planets Form?

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 491: Exoplanet Update 2018

Finally, a big update. Have there been news in the realm of exoplanets? More news that we can possibly cover. But we’ll try our best.

Ep. 464: Why the Hype over an Exorock?

Astronomers this week announced that they had discovered an asteroid or comet on a trajectory that brought it from outside the Solar System? Is this the first case of an object from deep space? And what can we learn from this discovery?

Ep. 390: Occam’s Razor and the Problem with Probabilities

I’m not saying it’s aliens, but it’s aliens. Actually, it’s almost certainly not aliens, or a wormhole, or a multiverse. When scientists discover something unusual, they make guesses about what’s happening. But Occam’s Razor encourages us to consider the probabilities of different events before making any concrete predictions.

Ep 386: Orbiting Observers

The atmosphere keeps us alive and breathing, but it really sucks for astronomy. Fortunately, humanity has built and launched space telescopes that get above the pesky atmosphere, where the skies are really clear. Let’s take a look at the past, current and future of orbital observation.

Ep. 375: The Search For Life in the Solar System

With the discovery of water ice in so many locations in the Solar System, scientists are hopeful in the search for life on other worlds. Guest Morgan Rehnberg returns to Astronomy Cast to explain the best places we should be looking for life.

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