Climate change is on our minds these days, with increasing wildfires, droughts and floods. What are the variables that play into a planet’s changing climate, and what can this teach us about the search for habitable planets across the Milky Way?
Ep. 644: Is Earth… Normal?
Now that we’ve discovered thousands of exoplanets, we’re learning more and more about what kinds of planetary systems there are out there across the Universe. Are planets like Earth unique or totally rare?
Ep. 641: Are Planets Alive?
The Earth is teeming with life, both in the upper atmosphere to kilometers underground. There’s no question that our planet has life. But is our planet itself alive? This is a question posed back in the 1970s as the Gaia hypothesis, and it got its share of criticism. Some new ideas have been proposed to bring this hypothesis to the modern era.
Ep. 627: Mercury Revisited
It’s been about a thousand years since we last looked at Mercury, so we figured it’s time for an update. What new things have we learned about Mercury, or even new questions? Fortunately, there’s a mission on the way to help get us some answers.
Ep. 626: Terrestrial Planets — Mercury, Venus, Earth, and Mars
We continue our refreshed tour of the Solar System, checking in on the inner terrestrial planets: Mercury, Venus, Earth and Mars. What have we learned about their formation, evolution and what they might tell us about other planets in the Universe?
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. 624: Small Rocky Bodies (Including Phobos and Deimos)
We’ve talked about the icy objects of the Solar System, today let’s talk about space rocks. There’s a surprising variety of rocky material in the Solar System, and each object has a story to tell about the history and formation of the planets, moons and other rocky bodies.
Ep. 623: NEOS: Concern or Nah?
Are asteroids dangerous? Just ask the dinosaurs, and they’ll tell you a sad story of fiery death. It turns out we’re in a shooting gallery of space rock and metal, and somewhere out there there’s one with our name on it. Should we be worried or are the risks so minimal to be irrelevant?
Ep. 622: Rocky Moons and Giant Asteroids
A rock is a rock is a rock, right? Across the Solar System there are giant rocky asteroids and even rockier moons. What’s the difference between these two families of objects, and where did they come from?
Ep. 621: Gas Giants
For the longest time, the only gas giant planets we knew about were Jupiter and Saturn. But now in the age of extrasolar planets, astronomers have discovered thousands of gas giants across almost as many star systems. What new discoveries have been made about gas giants, both here in the Solar System and across the Milky Way?
Ep. 620: Why Getting to the Outer Worlds is So Difficult
Good news! Over the next few years, we’re going to see a flotilla of new missions headed to Jupiter and Saturn. Why aren’t we seeing more missions to the outer planets, like Uranus and Neptune? It turns out, those places are far away. Today let’s talk about the challenge of exploring the outer Solar System.
Ep. 619: Icy Moons and Dwarf Planets
The outer Solar System is far enough from the Sun that water doesn’t get blasted away into deep space. In this icy realm, there are many worlds with vast quantities of water ice. Today let’s look at the icy outer moons and dwarf planets.
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. 615: Planet 9
After Pluto lost its planethood, we were down to 8 planets. But there’s growing evidence of another world (or worlds) out beyond the orbit of Pluto. Is Planet 9 out there and how will we find it? Could there even be a Planet 10?
Ep. 614: Centaurs, Comets and Asteroids
There are asteroids and there are comets. But there’s an entirely separate class of objects called centaurs. But instead of half-human, half-horse, imagine an object that’s half comet, half asteroid but 100% interesting.
Ep. 613: Pluto’s Demotion: 15 Years Later
Astronomy Cast more than 600 episodes ago. Are there any updates? Does Pluto have a chance of regaining planethood again?
Ep. 609: The Benefits of Volcanoes
Volcanoes can be some of the worst natural disasters we can experience here on Earth, but life wouldn’t even exist without them. What are volcanoes good for anyway?
Ep. 608: NASA Perseverance – The First 100 Days
As you all know, Pamela refuses to talk about any missions which aren’t actually doing science. Well, Perseverance has crossed the line, from fantasy to an actual working rover, scooping regolith and yeeting helicopters. What has the rover accomplished in its first 100 days?
Ep. 607: InSight and Marsquakes
Mars is cold and dead today, but the massive volcanoes tell us what the planet used to be like, millions and even billions of years ago. But how volcanically active is the planet today? That’s what NASA’s Mars InSight lander is there to figure out.
Ep. 600: Looking Ahead
Today, we gaze into the future of space and astronomy. What upcoming missions and events are we excited about?
Ep. 599: Zodiacal Light
Pamela has told us in the most flowery terms about the diffuse dust across inner solar system. Leftover from the formation the inner planets. Well, it turns out, she was wrong. Super wrong. Time to update.
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. 594: Juno – Primary Mission Highlights
Pamela’s always loathed to talk about spacecraft until the mission’s in space and the science is rolling. NASA’s Juno mission just received a mission extension, adding Jupiter’s moons to the menu. Now, finally, we can talk about Juno.
Ep. 590: Lunar Hazards: Dust, Radiation, and More
2024 can’t come soon enough. You know, that’s the year when humans will set foot on the Moon again. Don’t you roll your eyes. That’s the plan. Well, unless the plan changes. But my point is, explorers going to the Moon will need to be concerned about all kinds of hazards, like dust, radiation and gigantic moon worms.
Ep. 589: Lunar Resources: Water (Update) & Other Volatiles
We’ve talked about water on the Moon many times here on Astronomy Cast, but there have been a bunch of big updates, thanks to new research from NASA and others. Today we’re going to give you an update on the state of water on the Moon and the plans to take advantage of it.