Episodes

Ep. 303: Equilibrium

So many of the forces in space depend on equilibrium, that point where forces perfectly balance out. It defines the shape of stars, the orbits of planets, even the forces at the cores of galaxies. Let’s take a look at how parts of the Universe are in perfect balance.

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.

Ep. 301: Planetary Migration

We’re so familiar with the current configuration of the planets in the Solar System, but did the planets always orbit in this way? Did they form further out and then migrate inward to their current positions? And what about other star systems out there?

Ep. 300: What We've Learned in Almost 7 Years

We created Astronomy Cast to be timeless, a listening experience that’s as educational in the future as it was when we started recording. But obviously, things have changed in almost 7 years and 300 episodes. Today we’ll give you an update on some of the big topics in space and astronomy. What did we know back then, and what additional stuff do we know now?

Ep. 299: Space Stations, Part 4 — Future Space Stations

Sometimes a trilogy needs four parts. We’ve looked at the history and modern era of space stations but now it’s time to peer into the future at some space station concepts still in the works. Most of these will never fly, but the ideas are important. We can’t call ourselves a true space-faring civilization until humans live permanently outside the Earth.

Ep. 298: Space Stations, Part 3 — International Space Station

And now we reach the third part in our trilogy on space stations, with the largest vehicle ever assembled in space: the International Space Station. Launched in 1998, it now consists of 450 metric tonnes of modules, power systems and spacecraft and is regular host to a handful of astronauts from many countries.

Ep. 297: Space Stations, Part 2 — Mir

Last week we introduced the history of space stations and focused on the US and Soviet stations that were launched. This week we look at one of the longest running missions ever launched: Mir. From its launch and construction to its fiery finale, Mir helped both the Russians and the Americans extend their understanding of what it actually takes to live in space.

Ep. 296: Space Stations, Part 1 — Salyut and Skylab

It’s one thing to fly into space, and another thing entirely to live in space. And to understand the stresses and strains this puts on a human body, you’re going to need a space station. In this three-part series, we explore the past, present and future of stations in space, starting with the American Skylab and Russian Salyut stations.

Ep. 295: The Observable Universe

We understand our place in the Universe because of our direct observations. We can see the light that travelled billions of light years across space to reach us. This sphere of space is the observable universe; everything we can detect. But it’s really just a fraction of the larger, unobservable universe. Today, we’ll talk about both.

Ep. 294: The Arecibo Observatory

The mighty Arecibo Radio Observatory is one of the most powerful radio telescopes ever built – it’s certainly the larger single aperture radio telescope on Earth, nestled into a natural sinkhole in Puerto Rico. We’re celebrating the 50th anniversary of the construction of the observatory with a special episode of Astronomy Cast.