A rock is a rock is a rock, right? Across the Solar System there are giant rocky asteroids and even rockier moons. What’s the difference between these two families of objects, and where did they come from?
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Fraser Cain
Universe Today
Dr. Pamela Gay
CosmoQuest
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18 Seasons
700+ Episodes
2018 Winner Parsec Award
Ep. 621: Gas Giants
For the longest time, the only gas giant planets we knew about were Jupiter and Saturn. But now in the age of extrasolar planets, astronomers have discovered thousands of gas giants across almost as many star systems. What new discoveries have been made about gas giants, both here in the Solar System and across the Milky Way?
Ep. 620: Why Getting to the Outer Worlds is So Difficult
Good news! Over the next few years, we’re going to see a flotilla of new missions headed to Jupiter and Saturn. Why aren’t we seeing more missions to the outer planets, like Uranus and Neptune? It turns out, those places are far away. Today let’s talk about the challenge of exploring the outer Solar System.
Ep. 619: Icy Moons and Dwarf Planets
The outer Solar System is far enough from the Sun that water doesn’t get blasted away into deep space. In this icy realm, there are many worlds with vast quantities of water ice. Today let’s look at the icy outer moons and dwarf planets.
Recent Episodes
Questions Show: Shooting Lasers at the Moon and Losing Contact with Rovers
This week we find out how hard it is to hit the Moon with a laser, and if scientists lose contact with the Mars rovers when they go behind the Sun. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to...
Ep. 128: Dust
You can't make a Solar System without a whole lot of dust. And that's the problem. This dust has blocked astronomers views into some of the most fascinating parts of the cosmos. It shields the galactic core, enshrouds newly forming stars and their planets, and blocks...
Ep. 127: The US Space Shuttle
You’ve heard us talk about capsules, you’ve heard us talk about space suits, well today we take a look at the only currently in use reusable space craft. It’s a not a bird, its not a plane – It’s the US Space Shuttle. And to make it interesting – we’ve sent Scott...
Ep. 126 From Skeptics Guide with Questions
This week Bob Novella of Skeptics Guide to the Universe is going to pepper Pamela with questions, testing her ability to leap from tides to gravitational waves to Higgs bosons. We'll see where this takes us on this skeptical journey through what is known and what...
Ep. 125: A Zoo of Extrasolar Planets
Dreaming up new planets is a favourite pastime of science fiction writers, but the universe often has them beat – coming with planets in place and forms that we had quite thought to imagine. Today we know of 228 planets orbiting alien stars, and in this episode we...
Questions Show: Moons and the Drake Equation, Stars in the Void, and Rings Around Stars
This week we find out if moons around other planets could support life, if there's anything out there between galaxies, and whether stars form rings. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to...
Ep. 124: Space Capsules, Part 1 – Vostok, Mercury and Gemini
The space capsule has been around for almost 50 years, when Yuri Gagarin headed to space in 1961. There have been many programs that used capsules by both the Americans and the Russians, and even the Chinese are using them now for their spaceflight program. Let's take...
Ep. 123: Homogeneity
As astronomers discovered that we live in a great big universe, they considered a fundamental question: is the universe the same everywhere? Imagine if gravity was stronger billions of light years away... Or in the past. It sounds like a simple question, but the...
Ep. 122: How Old is the Universe?
We did a wildly popular three part series about the center, size and shape of the Universe. But every good trilogy needs a 4th episode. This week we look at age of the Universe. How old is the Universe, and how do we know? And how has this number changed over time as...
Questions Show: Stellar Roche Limits, Seeing Black Holes, and Water on Mars
This week we find out when stars get torn apart from gravity, how we can see supermassive black holes, how liquid water could have existed on Mars in the past, and much more. If you've got a question for the Astronomy Cast team, please email it in to...
Ep. 121: Spacesuits
As we've mentioned before, the Universe is trying to kill you. And for astronauts, that's truer than ever. One step out into the vacuum of space would be a world of hurt for an unprotected astronaut: the freezing cold temperature, the lack of atmospheric pressure, and...
Ep. 120: The Christmas Star
With Christmas just around the corner, we thought we'd investigate a mystery that has puzzled historians for hundreds of years. In the bible, the birth of Jesus was announced by a bright star in the sky that led the three wise men to his birthplace. What are some...
Questions Show: Different Fields of Astronomy, Our Sibling Stars, and Hidden Lagrange Points
This week we find out the difference between an astronomer, an astrophysicist, and a cosmologist, the search for the stars that shared our nebula, hidden objects in Lagrange points, and much more.. If you've got a question for the Astronomy Cast team, please email it...
Ep. 119: Robots in Space
Space is totally inhospitable. If the freezing temperatures don't get you, the intense radiation will kill you. Or the vacuum, or the lack of breathable atmosphere, or meteoroid impacts. Well... you get the idea. That's why most space exploration is done by hardy...
Questions Show: Distance in Space, Changing Earth's Orbit, and Different Sized Stars
This week we find out the distance between Betelgeuse and Bellatrex, how astronomers measure distance between objects, the possibility that an object could mess up the orbit of Earth, and the reason for different sizes of stars. If you've got a question for the...
Ep. 118: Sky Surveys
In the old days, astronomers had to beg for telescope time. They'd put together a proposal, convince observatories to gather data for them, crunch that data and release the results. No telescope, no results. But everything's different now. Fleets of robotic telescopes...
Ep. 117: Time
Today, time rules our lives. We live each day with the moments broken up into hours, minutes and seconds. We never seem to have enough time. But can you imagine not being able to tell time at all, where the movements of the Sun and the stars was the only way to know...
Ep. 116: Molecules in Space
As part of her trip to England, Pamela had a chance to sit down with Oxford astrophysicist Chris Lintott and record an episode of Astronomy Cast. From the first stars to the newest planets, molecules and the chemistry that allows them to form affects all aspects of...
Ep. 115: The Moon, Part 3: Return to the Moon
It's time for a third lunar chapter. We've talked about the physical characteristics of the Moon, and the exploration. Now we're going to talk about the plans to return to the Moon. From the upcoming lunar reconnaissance orbiter to the plans to have humans set foot on...
Questions Show: Spiral Arms, Seismic Waves on the Sun, and our Favorite Gear
This week we explore galactic spiral arms, seismic quakes on the Sun, and our picks for astronomy gear. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show. Please include your...