
Ep. 509: Fiction to Fact: 3D Printers
The technology of 3D printing is taking off. From tiny home-based 3D printers to larger manufacturing. And of course, 3D printing is going to space with the International Space Station and beyond.

Ep. 508: 2018 Holiday Gift Guide
We did it, we made it to the end of another year. Once again it’s time to wonder what gifts to get your beloved space nerds. We’ve got some suggestions. Some are brand new this year, others are classics that we just can’t help but continue to suggest. Let’s get into it.
Ep. 507: From Fiction to Fact : Ion Drive
Ion engines are a mainstay of science fiction, featured in both Star Trek and Wars. But this is a very real technology, successfully used on several missions out there in the Solar System right now. How do they work and what are the limits?
Ep. 506: It’s not Aliens, Unless it’s Aliens
Did you hear that astronomers from Harvard think that the interstellar asteroid Oumuamua was actually an alien solar sail? Is it aliens? Of course it’s not aliens. But some day, it’ll actually be aliens.
Ep. 505: Seismology
We’re always interested in the surface features of the planets and moons in the Solar System, but that’s only skin deep. It turns out, these worlds have an interesting inner life too. Thanks to the science of seismology, we can peer into our planet and learn how it works… inside. And we’re about to take that technology to Mars.
Ep. 504: Radar, Lidar, and Sonar
To really study something, you want to reach out and touch it. But what can you do if you’re separated by a huge distance? You reach out with electromagnetic or sound waves and watch how they bounce back. Thanks to radar, sonar and lidar.
Ep. 503: Gravity Mapping
The Earth looks like a perfect sphere, but down here on the surface we see that there are mountains, rivers, oceans, glaciers, all kinds of features with different densities and shapes. Scientists can map this produce a highly detailed gravity map of our planet. And it turns out, this is very useful for other worlds too.
Ep. 502: No Touching: Determining Composition of Worlds Remotely
How do you know what something is made of if you can’t reach out and touch it? How do we know what planets lights years away have in their atmosphere? What about the rocks all around Curiosity? Or the geysers coming out of Europa and Enceladus? Scientists have a few handy tricks.
Ep. 501: Water Worlds Revisited
We’re not learning that the vast majority of potentially habitable worlds out there are actually icy moons like Europa and Enceladus. Good news, there are hundreds, if not thousands of times more of them than worlds like Earth. Bad news, they’re locked in ice. What have we learned about water worlds and their potential for habitability?
Ep. 500: Live Celebration!
Welcome to episode 500 of Astronomy Cast. To celebrate this momentous occasion, we’re going to look back 500 years into the past to see what we learned about the Universe. And then we’re going to look 500 years into the future.