Ep. 113: The Moon, Part 1

Hey, here’s a topic we haven’t really gotten around to yet… the Moon. Today we look at our closest astronomical companion: the Moon. What impact does the Moon have on our lives, where did it come from, who walked on it, and are we ever going to walk on it again? We’re going to learn about the phases, the tides, and even a little bit about NASA’s plans to send humans back to the Moon.

Ep. 108: The Life of the Sun

We’ve talked about the Sun before, but this time we’re going to look at the entire life cycle of the Sun, and all the stages it’s going to go through: solar nebula, protostar, main sequence, red giant, white dwarf, and more. Want to know what the future holds for the Sun, get ready for the grim details.

Ep. 96: Humans to Mars, Part 3 – Terraforming Mars

And now we reach the third part of our trilogy on the human exploration and colonization of Mars. Humans will inevitably tire of living underground, and will want to stretch their legs, and fill their lungs with fresh air. One day, we’ll contemplate the possibility of reshaping Mars to suit human life. Is it even possible? What technologies would be used, and what’s the best we can hope for?

Ep. 95: Humans to Mars, Part 2 – Colonists

After astronauts make the first tentative steps onto the surface of Mars, a big goal will be colonization of the Red Planet. The first trailblazers who try to live on Mars will have their work cut out for them, being in an environment totally hostile to life. What challenges will they face, and how might they overcome them?

Ep 94: Humans to Mars, Part 1 – Scientists

We’re learned about the failed missions to Mars in the past, and the current spacecraft, rovers and landers currently exploring the Red Planet. But the real prize will come when the first human sets foot on Mars. Robots are cheaper, but nothing beats having a real human being on the scene, to search for evidence of water and life.

Ep. 93: Missions to Mars, Part 2

I know last week was a bit of a dry history lesson, but we wanted to give you some understanding of past efforts to explore Mars. Now we’ll look at the missions currently in orbit, and crawling around the surface of Mars, and help you understand the science that’s happening right now.

Ep. 91: The Search for Water on Mars

With the successful touchdown of the Phoenix Lander, NASA is continuing its quest to find evidence of past and present water on Mars. This week we discuss the geologic history of Mars, and explain why NASA thinks the story of water on Mars is so important. And how this ties into the search for life on the Red Planet.

Ep. 86: The End of the Universe Part 1: The End of the Solar System

This is a show we wanted to do since we started Astronomy Cast but we always thought it was too early. We wanted you to know that we’re positive, happy people with enthusiasm for astronomy and the future. It’s time for some sadness. It’s time for a grim look to see what the future holds for the Universe. This week we stay close to home and consider the end of humanity, the Earth, the Sun, and the entire Solar System. Next week we’ll extend out to the very end of the Universe.

Ep. 84: Getting Around the Solar System

Have you ever wondered what it takes to get a spacecraft off the Earth and into space. And how managers at NASA can actually navigate a spacecraft to another planet? And how does a gravity assist work? And how do they get them into orbit? And how do they land? So many questions…

Ep. 82: Space Junk

We’re polluting every corner of our own planet, so it only makes sense that we’ll take our trashy habits out into space with us. This week we look at the myriad of ways we’re messing up space, from the trash orbiting the planet to the radiation we’re leaking out into space.

Ep. 76: Lagrange Points

Gravity is always pulling you down, but there are places in the solar system where gravity balances out. These are called Lagrange points and space agencies use them as stable places to put spacecraft. Nature is on to them and has already been using them for billions of years.

Ep. 65: The End of Our Tour Through the Solar System

All good things come to an end – we now find ourselves in the outer reaches of the solar system where our Sun is hard to distinguish from the other bright stars in the sky. But we’re not done with the solar system, there’s some stuff that’s leftover. This week, we look at the outer reaches of the solar system and how it interacts with the rest of the universe.

Ep. 64: Pluto and the Icy Outer Solar System

It’s been a long journey, 64 episodes, but now we’re back where we began: Pluto. Last time we talked about how Pluto lost its planethood status, so we won’t go over all that again. This time we’re going to talk about Pluto, its moons, the Kuiper belt, and the other icy objects that inhabit the outer Solar System.

Ep. 63: Neptune

We’ve reached Neptune, the final planet in our tour through the solar system – but don’t worry! The tour’s not over, but after this week we’ll be all out of planets. Neptune has a controversial story about its discovery, some of the strongest winds in the solar system and some weird moons.

Ep. 62: Uranus

This week, we’re on to the next planet in the solar system. We don’t know a whole lot about this blue gas planet, but today we’ll cover some of the neat stuff we do know, including it’s faint rings, sideways axis of rotation and its rocky core – a first in the gas planets we’ve encountered so far in our tour.

Ep. 61: Saturn's Moons

We know that delaying this show one more week would be too dangerous, so here you go: Saturn’s moons. These are some of the most interesting objects in the Solar System, from the spongy Hyperion, to the geysers on Enceladus, to the rainy, misty, oceany Titan. They’ve kept Cassini busy for years, and scientists will likely be pondering them for decades.

Ep. 59: Saturn

Returning to our tour of the solar system, let’s voyage away from the largest planet to the second largest, Saturn. Once again, we’ll break up our visit because there’s lots to talk about. This week, we talk about Saturn and its famous rings. Next week, we’ll discuss its many moons.

Ep. 57: Jupiter's Moons

Last week we talked about Jupiter and we could sense right away it would be too much to handle. This week, we’ll talk about Jupiter’s moons – how many are there? What makes them so interesting? Is it true that the most likely place in the solar system to find life (other than Earth) is actually on one of Jupiter’s moons? Hang on tight. We’re going to cover a lot.

Ep. 56: Jupiter

Last week we talked about rubble, this week we’re going to dig into the largest planet in the Solar System: Jupiter, but will it all just be hot gas? There’s so much to talk about, we’ve decided to break this up into two shows. This week we’re going to just talk about Jupiter, and then next week, we’re going to cover its moons.

Ep. 55: The Asteroid Belt

In the last few weeks we’ve had many emails saying that our tour of the solar system would not be complete without a show on the asteroid belt. Your wish is our command! We talked about Mars in episode 52, and now that we’re back on track our next stop is the asteroid belt.

Ep. 52: Mars

Today we consider Mars, the next planet in our journey through the Solar System. Apart from the Earth, it’s the most explored planet in our Solar System. Even now there are rovers crawling the surface, orbiters overhead, and a lander on its way. It’s a cold, dry desert, so why does this planet hold such fascination?

Ep. 51: Earth

Another week, another planet. This time we talk about our own home world: Earth. You might think you know the planet beneath your feet, but it’s actually one of the most interesting and dynamic places in the Solar System. Learn about our planet’s formation, weather, its changing climate, and life.

Ep. 50: Venus

Last week we talked about Mercury, so this week our planetary parade proceeds to Venus. It’s the brightest object in the sky, the hottest object in the solar system, and it’s probably one of the most deadly places to go and visit.

Ep. 49: Mercury

We’re still digging through the thousands of comments and suggestions from the listener survey but we hear your requests and suggestions, and now you get to start reaping the benefits. Today we start our survey of the solar system with Mercury. What mysteries is it hiding from us? How similar is Mercury to the other rocky planets? How much do we really know about this first rock from the Sun?

Ep. 30: The Sun, Spots and All

It’s Spring in the Northern Hemisphere, and that means the Sun is back. But it’s more than just a free heat lamp for your garden, it’s an incredible, dynamic nuclear reaction complete with flares, coronal mass ejections, twisting magnetic fields and the solar wind. Put in your headphones, head outside and enjoy the sunshine while you listen to this week’s podcast.
Correction: At the beginning of the show I say the Sun has 50 billion years to go. I mentally combined two numbers. In 50 million years life will become untenable or impossible on Earth. In 5 billion years the sun goes off the main sequence. We are very sorry for the mistake. -Pamela