Fraser Cain
Universe Today
Dr. Pamela Gay
CosmoQuest
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.
There are general-purpose telescopes and missions that astronomers can use to study specific objects. And there are survey missions that look at the entire sky, which astronomers can use to answer questions about the Universe. We’ve talked about surveys in the past, but the landscape is changing fast so it’s time for an update.
Knowledge moves forward, and so, we must move with it. Today we’ll give you an update on some of the most fascinating, and fast-changing topics in astronomy, astrophysics and cosmology.
Although humans have never actually been to Mars, explorers have simulated many aspects of Mars missions here on Earth. There are missions under the ocean, on the tops of volcanoes, in the harsh Canadian north, and even in bed that simulate the limitations of spaceflight, and teach us many of the lessons to prepare us for the real thing.
Recent Episodes
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...
When too much material tries to come together, everything starts to spin and flatten out. You get an accretion disc. Astronomers find them around newly forming stars, supermassive black holes and many other places in the Universe. Today we'll talk about what it takes...
Last week we explored the various ways spacecraft can die. But this week, we explore the spacecraft (and the scientists) who never give up, snatching victory from the jaws of defeat. We'll look at clever solutions to potential spacecraft catastrophes. Download the...
In the end, everything dies, even plucky space robots. Today we examine the last days of a series of missions. How do spacecraft tend to die, and what did in such heroes as Kepler, Spirit, and Galileo (the missions... not the people). Download the show [MP3] | Jump to...
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....
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...
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? Download the...
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...
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...
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...
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...
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...
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...
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...
We always say that the Universe is trying to kill you, but actually, the Earth isn't so fond of you either. Certain parts of planet Earth are prone to earthquakes, where the planet's shifting plates can cause the ground to shake violently. We've had a few devastating...
The very outer reaches of the Solar System is a region of space known as the Oort Cloud, which may extend as far as a light-year from the Sun. We only know about the Oort Cloud because that's where long-period comets come from, randomly falling into the inner Solar...
As a meteor crashed into the atmosphere above Russia, the world discovered the importance of shock waves; how they're caused and how they propagate through the atmosphere. Today we'll discuss the topic in general and find many examples where shock waves can be...
If you get enough hydrogen together in one place, gravity pulls it together to the point that the temperature and pressures are enough for fusion to occur. This is a star. But what happens when you don't have quite enough hydrogen? Then you get a failed star, like a...
Sure, our atmosphere protects us from a horrible Universe that's trying to kill us, but sometimes it prevents us from learning stuff too. Case in point, the atmosphere blocks highly energetic particles from reaching our detectors. But there's a way astronomers can...
As we quickly learn with water, matter can be in distinct phases: solid, liquid, gas and plasma; it all depends on temperature. But why do different materials require different temperatures? And what's actually happening to the atoms themselves as the material...