Ep. 429: Living on Mars

When Elon Musk announced plans to send humans to Mars, he conveniently left out one important aspect. How are we supposed to survive on a place this hostile to life? Seriously, Mars sucks, and it’s going to take some impressive techniques and technologies to make it on the Red Planet.

Ep. 428: The Moons of Mars

We begin a miniseries on Mars. How many episodes will we do? Who knows? But we start today with a discussion of the two Mars moons, Phobos and Deimos.

Ep. 422: Geysers

So if you’ve been to Yellowstone National Park, you’ve seen one of the most amazing features of the natural world – geysers. In today’s episode, we’re going to talk about geysers on Earth, and where they might be in the solar system.

Ep. 410: Planet 9 Facts and Fiction

The discovery of Planet 9 has caused a wonderful, confusing uproar and a flood of misinformation in the news and social media. We’ll sort out what we actually know, what things just aren’t true, and what things might be possible!

Ep. 409: Spin in the Solar System

The Solar System is a spinny place. Everything’s turning turning. But if you look closely, there are some pretty strange spins going on. Today we talk about how everything started turning, and the factors that still “impact” them today.

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 387: Water on Mars… Again

Have you heard the big news? NASA has reported that Mark Watney is alive and well on the surface of Mars. No, wait, they’ve reported that there’s water on Mars. Didn’t they already report this? Today we’ll update you on the latest discovery and what this means for the search for life on Mars.

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 385: Rovers on the Run

Taking pictures of distant worlds is great and all, but the best science happens with boots on the ground. Or in this case… wheels. This week we’ll talk all about robotic rovers and the places they rove.

Ep. 384: Escaping Probes

The gravity of the Earth is a tough thing to escape, but breaking free from the gravity of the Sun is on a whole other level. But humans have achieved this amazing accomplishment, and right now there are several spacecraft leaving the Solar System and never coming back.

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.

Ep. 366: HARPS Spectrograph

Almost all the planet hunting has been done from space. But there’s a new instrument installed on the European Southern Observatory’s 3.6 meter telescope called the High Accuracy Radial velocity Planet Searcher which has already turned up 130 planets. Is this the future? Searching for planets from the ground?

Ep. 364: The COROT Mission

Before NASA’s Kepler mission searched for exoplanets using the transit method, there was the European COROT mission, launched in 2006. It was sent to search for planets with short orbital periods and find solar oscillations in stars. It was an incredibly productive mission, and the focus of today’s show.

Ep. 363: Where Did Earth's Water Come From?

Where on Earth did our water come from. Well, obviously not from Earth, of course, but from space. But did it come from comets, or did the water form naturally right here in the Solar System, and the Earth just scooped it up?

Ep. 354: Comet Siding Spring vs. Mars

We were witness to a once in a million year event. A close approach of Comet Siding Spring to the Planet Mars. And fortunately, humanity had a fleet of spacecraft orbiting the Red Planet, ready to capture this monumental event in real time. What did we see? What will we learn?

Ep. 353: Seasons on Saturn

You think we’re the only place that experiences seasons? Well, think again. Anything with a tilt enjoys the changing seasons, and that includes one of the most dramatic places in the Solar System: Saturn, with its rings and collection of moons.

Ep. 352: Water, Water Everywhere!

Where ever we find water on Earth we find life. And so, it makes sense to search throughout the Solar System to find water. Well, here’s the crazy thing. We’re finding water just about everywhere in the Solar System. This changes our whole concept of the habitable zone.

Ep. 344: The Rings of Saturn

There’s so much we know about Saturn’s beautiful rings, and yet, there’s so much we don’t know. Morgan Rehnberg, a PhD student at the University of Colorado, Boulder and works with the Cassini mission. Morgan joins Fraser to talk about Saturn’s amazing rings, and how they might have formed.

Ep. 326: Atmospheric Dust

When you consider the hazards of spaceflight, it’s hard to get worked up about dust bunnies. And yet, atmospheric dust is going to be one of the biggest problems astronauts will face when they reach the surface of other worlds. Where does this dust come from, and what does it tell us about the history of other worlds, and what can we do to mitigate the health risks?

Ep. 324: Sun Grazers

Comets can spend billions of years out in the Oort Cloud, and then a few brief moments of terror orbiting the Sun. These are the sun grazers. Some survive their journey, and flare up to become the brightest comets in history. Others won’t survive their first, and only encounter with the Sun.

Ep. 320: Layers of the Sun

Our Sun isn’t just a terrifying ball of white hot plasma, it’s actually a lot more complex. It’s got layers. And today, we’re going to peel back those layers and learn about the Sun – from the inside out.

Ep. 311: Sound

Shhhh, shhh. You can stop screaming. That’s because nobody can hear you … in space. But why not? How does sound work here on Earth, and what would it sound like on other planets?

Ep. 308: Climate Change

When it comes to carbon dioxide, just a little goes a long way to warming the planet. Unfortunately, we’ve been dumping vast amounts into the atmosphere, recently passing 400 parts per million. Let’s look at the science of the greenhouse effect, and how it’s impacting our global climate.

Ep. 307: The Pacific Ring of Fire

The Pacific Ring of Fire wraps around the Pacific Ocean, including countries like Japan, Canada, New Zealand and Chile. And the inhabitants within those countries are prone to… oh… killer earthquakes, volcanoes and tsunamis. Let’s chat about the history of this region and the kinds of risks they face.

Ep. 302: Planetary Motion in the Sky

Even the ancient astronomers knew there was something different about the planets. Unlike the rest of the stars, the planets move across the sky, backwards and forwards, round and round. It wasn’t until Copernicus that we finally had a modern notion of what exactly is going on.