It’s been a while since we checked to make sure the Universe was still expanding. Yeah, apparently, that’s still a thing. But in the last few years powerful new telescopes and expansive surveys have given us much more knowledge about what’s happening.
Our Hosts
Fraser Cain
Universe Today
Dr. Pamela Gay
CosmoQuest
Production by
- Richard Drumm, Audio Engineer
- Ally Pelphrey, Video Engineer
Ep. 596: Universe’s Background Noise
You might be familiar with the cosmic microwave background, but that’s just one of the background radiations astronomers look at. Some are well known and cataloged, while others are just starting to be possible to see. All of them tell us more about our Universe.
Ep. 595: Planet Hunting (Updated)
This is going to be another one of those evergreen topics, where we come back to again and again. Finding planets. Every time we talk about this now, it seems like we’ve gained thousands of new planets. Well buckle up, new techniques will grow that by tens of thousands and even millions.
Ep. 594: Juno – Primary Mission Highlights
Pamela’s always loathed to talk about spacecraft until the mission’s in space and the science is rolling. NASA’s Juno mission just received a mission extension, adding Jupiter’s moons to the menu. Now, finally, we can talk about Juno.
Recent Episodes
Questions Show: Relativity, Relativity and More Relativity
Everyone loves a theme. And this week we've collected together some of your questions about relativity. More light speed spacecraft, twin paradoxes, and the mixing up of gravity, time and mass. If you've got a question for the Astronomy Cast team, please email it in...
Ep. 111: Nebulae
When you think about the best pictures in astronomy, almost every one is a nebula; the pillars of creation in the Eagle Nebula, or the complex Helix Nebula - or my personal favourite, the Ring Nebula. They're beautiful, wispy clouds of gas and dust that signify both...
Questions Show: Galactic Dust, the Speed of Photons, and the Big Bang Calculations
Another week, another roundup of your questions. This week listeners asked: what is galactic dust anyway, and where does it come from? Why can photons move at the speed of light? And how can astronomers know what happened right after the Big Bang? And there's even...
Ep. 110: The Search for Extraterrestrial Intelligence
You know what this show needs? More aliens. Since we don't seem to have any visiting right now, we're going to have to find some. SETI is an acronym. It stands for the Search for Extraterrestrial Intelligence. But there's more to SETI than just putting up a radio...
Questions Show: Alignment with the Galactic Plane, Destruction from Venus, and the Death of the Solar System
Another week, another roundup of your questions. This week listeners asked: are we all going to die in 2012 when the solar system passes through the galactic plane? Did Venus make the Moon? And what will extraterrestrials see when the Sun is dead and gone? And there's...
Ep. 109: The Life of Other Stars
Last week we looked at the complete life of the Sun, birth to death. But stars can be smaller, and stars can get much much larger. And with a change in mass, their lives change too. Let's start the clock again, and see what happens to the smallest stars in the...
Questions Show – Running Out of Gravitons and Hitting the Brakes at Light Speed
Another week, another roundup of your questions. This week listeners asked: if forces are communicated through particles, can we run out? If you were traveling at light speed, when would you know to stop? And there's even more. If you've got a question for the...
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...
Questions Show – light speed, Andromeda galaxy, dark matter and black holes
Another week, another roundup of your questions. This week listeners asked: will reaching light speed destroy the Universe? When is Andromeda going to look really, really cool with the unaided eye? Why didn't dark matter all turn into black holes? And there's even...
Ep. 107: Nucleosynthesis: Elements from Stars
Look around you. Breathe in some air. Everything you can see and feel was formed in a star. Today we'll examine that long journey that matter has gone through, forged and re-forged in the hearts of stars. In fact, the device you're using to listen to this podcast has...
Questions Show – Black Hole Surfaces, Magnetic Field Strengths, and the Speed of Gravitons
As you know, we wanted to answer listener questions regularly, but we found it was taking away from the regular weekly episodes of Astronomy Cast. So we've decided to just split it up and run the question shows separately from the regular Astronomy Cast episodes. If...
Ep. 106: The Search for the Theory of Everything
At the earliest moments of the Universe, there were no separate forces, energy or matter. It was all just the same stuff. And then the different forces froze out, differentiating into electromagnetism, the strong force and the weak force. Today we'll look at the...
Student Questions Show: Leelanau School
This is our forth installment in our series of student questions shows and these questions come to us from Leelanau High School. Thanks to GLAST, Astronomy Cast is now able to provide equipment to send to high school teachers who want to Pamela and Fraser to do a...
Ep. 105: The Strong and Weak Nuclear Forces
After a quick Dragon*Con break, we're back to our tour through the fundamental forces of the Universe. We've covered gravity and electromagnetism, and now we're moving onto the strong and weak nuclear forces. We didn't think they'd really need to be separate episodes,...
Ep 104: Science Fiction at Dragon*Con with Plait and Grazier
Pamela left Fraser behind (with sorrow) and took on Dragon*Con and the facts (or lack there of) in Science Fiction. Helping her out were special guests Phil Plait and Kevin Grazier. Ep. 104: Science Fiction at Dragon*Con with Plait and Grazier Jump to Shownotes Jump...
Ep. 103: Electromagnetism
Our series on the basic forces of the cosmos continues! Last week we discussed gravity, and this we'll handle electromagnetism. Electricity and magnetism are just two aspects of the same force, and you can't talk about astronomy without understanding these two keys...
Ep 102: Gravity
You seem to like a nice series, so here's a new one we've been thinking about. Over the course of the next 4 weeks, we're going to cover each of the basic forces in the Universe. And this week, we're going to start with gravity; the force you're most familiar with....
Ep. 101: Advanced Propulsion Systems
Last week we talked about rockets. How they work and their limitations. This week we're going to look at the future of propulsion systems. From the ion engines that are already working to explore the Solar System to the prototype solar sails to futuristic technologies...
Ep. 100: Rockets
To move around in space, you need some kind of propulsion system. And for now, that means rockets. Let's learn the underlying science of rockets, and how they work. And learn why a rocket will never let us reach the speed of light. Ep. 100: Rockets Jump to Shownotes...
Ep. 99: The Milky Way
The Milky Way is our home. An island of stars in a universe of other galaxies. But you might be surprised to learn that astronomers have only known the Milky Way's true nature for just a century. Let's learn the history of discoveries about the Milky Way, and what...