Joshua Colwell, Adrienne Dove, and James Cooney

Walkabout the Galaxy

Science EN ↓ 369 episodes

An irreverent and informative tour of the latest, greatest, and most interesting discoveries in astronomy.

Author

Joshua Colwell, Adrienne Dove, and James Cooney

Category

Science

Latest episode

Jul 9, 2026

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Episodes

Of Eclipses and Starspots 31.08.2017

The astroquarks tell their eclipse stories from the Great American Eclipse. The Sun and every star has weather, spots, oscillations, flares and all sorts of activity. Some of this is revealed during an eclipse to the naked eye. Now, telescopes have enabled us to map the appearance of the red supergiant, Antares. Join Josh, Addie and Jim for this stellar episode of Walkabout the Galaxy.

Of Zombies, Comets and Kilograms 17.08.2017

The weight on that box of breakfast cereal ultimately traces back to "le grand K", a metal sphere in a vault in Paris, a wonderfully archaic standard for how much stuff makes a kilogram. We'll talk about the efforts to update that standard, the next Kuiper Belt Object to be explored by the New Horizons spacecraft, eclipses and occultations, and of course Zombies. Join the astroquarks for the lates...

Cold and Hard, not Warm and Fuzzy 10.08.2017

The Sun doesn't just shine, it rings like a bell, or a drumhead wrapped into a ginormous ball of incandescent plasma. The astroquarks talk about how helioseismology tells us about the interior of the Sun, and new research shows some surprising changes in the Sun's outer layers. And the disappointing news from the realm of cosmology is that dark matter is probably not warm and fuzzy, depriving us o...

Going Rogue! 30.07.2017

If the controversy over Pluto's planetary status weren't already enough, what do you call a planet that is not even orbiting a star? The astroquarks explore rogue planets in this episode, planets that wander interstellar space, without a fire to keep them warm. We discuss how they nevertheless have been detected. Also, Addie's favorite body (rhymes with loon) and Jim's new favorite name, nerd news...

Teleport Me to the Great Red Spot! 21.07.2017

Dr. Kristen John of NASA's Johnson Space Center joins the Astroquarks for a wide-ranging discussion on topics from Jupiter's Great Red Spot to teleportation (yes, it's a real thing) and just what that means (not at all clear, but don't get ready to step into that transporter beam just yet). 

Where No One Has Gone Before 09.07.2017

The astroquarks are joined by Dr. Phil Metzger who spends a lot of time thinking about how our civilization can make the great leap into space. We may not be that far away from truly moving off our home planet and becoming a "Type 1 Civilization" that inhabits the solar system and not just one planet. We discuss how we'll get there, how long it might take, the challenges we face, and of course the...

Is Planet 9 Lost in Space? 28.06.2017

Planet 9, also known as Egotron in honor of its supporters, has never been seen. A new statistical analysis of a deep sky survey suggests that's because it doesn't exist. The object's existence has been proposed to explain an apparent clustering of the orbits of some objects that have the charming quality of actually having been directly observed. The astroquarks discuss the arguments for Egotron...

Leggo my LIGO! 21.06.2017

The astroquarks take a look at new indications of water ice on the Moon, evidence that Jupiter formed in less than a million years, and the third detection by LIGO of gravitational waves from a black hole merger. All that, NASA's new astronaut class, New Horizons, and the summer sci-fi blockbuster and blockbuster wannabes on this episode of Walkabout the Galaxy.

Uranus Gets Bedazzled! 03.06.2017

How many jokes can the three astroquarks make about the pronunciation of the seventh planet? You'll have to tune in to this episode of WtG to find out. Josh, Addie and Jim discuss how aurorae on planets are made and why seeing them on Uranus is surprising. Also, is there a new type of planetary object, or is it just more hot gas? Find out about the Synestia, Uranus, nerd news and Star Trek trivia...

Is That Inflation Or Are You Just Happy To See Me? 26.05.2017

You may think of inflation as prices creeping higher, but to a cosmologist it's been an important idea to explain why the universe is so uniform on very large scales in every direction we look. But does inflation pass muster as a testable scientific theory? The astroquarks review what inflation is all about as there is renewed discussion in the scientific community about the theory and its predict...

Juno What I Mean! 17.05.2017

The Juno mission is studying Jupiter's interior, but its citizen-scientist JunoCam is returning stunning images of the largest planet. Hear the astroquarks Josh Colwell, Addie Dove and Jim Cooney provide equally stunning descriptions of those pictures. You will hear color! If you're on mind-altering substances. Otherwise it will be a tour of the solar system, from Jupiter to Mars to Comet 67P. All...

The Solar System is a Bubble in Space 10.05.2017

Josh and Addie welcome two special guests for this episode of Walkabout the Galaxy where we learn about a new and clever measurement of the size and shape of the heliosphere. Cooler still, some of the critical data came from our old friend Cassini and even older friends the Voyager spacecraft. All this, plus trivia, nerd news and a galaxy-sized wave of hot gas. 

The Grand Finale is Finale Here 28.04.2017

No, that ain't no negative mass, but yes, for Cassini the end is nigh. The series of 22 Grand Finale orbits has begun, providing unique views of Saturn and its rings and a way to probe the planet's interior and magnetic field. The astroquarks also check out yet another exoplanet in the habitable zone of a nearby star and discuss the headline about a discovery of "negative mass". 

Enceladus is a Little Bit Gassy! 15.04.2017

The astroquarks dissect the latest news from Saturn's intriguing moon Enceladus. Molecular hydrogen in its geysers suggest that Enceladus' ocean floor has the same kinds of hydrothermal energy sources that may have powered the origin of life on Earth. Plus, lots of Star Wars nerd news, and from the cosmological realm the first map of dark matter bridges connecting pairs of galaxies. 

That's Quite a Hadron You've Got There! 05.04.2017

The Large Hadron Collider announced five new subatomic particles recently. Top astroquark Jim Cooney is our go-to quark for all things quarky, so he explains what's going on with these new particles. Charm astroquark Addie Dove gives us the latest rocket news, and Strange astroquark Josh Colwell discovers that there's something good about "Starship Troopers". Tune in for the latest news in astrono...

The Great Black Hole Escape 27.03.2017

What are gravitational waves good for? Getting rid of that pesky supermassive black hole that's outstayed its welcome, for one thing. Join the astroquarks, Josh Colwell, Addie Dove and Jim Cooney, for a journey from a comet with landslides to a distant galaxy that is losing its central black hole. All that, nerd news, and more on this episode of Walkabout the Galaxy.

Space Dust Keeps Falling on my Head 19.03.2017

On this Pi-Day recording of WtG, the astroquarks have a special trivia question and science topics ranging from interplanetary dust to Saturn's intriguing ravioli-shaped moon Pan, and antimatter. Find out how much more energetic you'd feel if you metabolized food the way Star Trek's antimatter engines work instead of through boring chemical reactions.  

The One About Patrick Stewart 12.03.2017

There are black holes and interferometry in this episode, but the nerd news segment on Patrick Stewart either sets a new standard or a new low. You be the judge as the astroquarks, Josh Colwell, Addie Dove and Jim Cooney take a look at advances in imaging the event horizon of the supermassive black hole at the center of our galaxy.

Strange New Worlds 28.02.2017

A system of seven Earth-sized planets has been observed orbiting a (relatively) nearby star. At least three of these planets are in the habitable zone, or as Top Astroquark Jim Cooney would say, the haBITable zone. That's where there may be liquid water on the surface of the planet. The star for these planets is tiny and not so hot, so the planets are huddled around it like campers around the embe...

White Dwarfs and Planetary Nebulae 17.02.2017

It's the plural episode of Walkabout as the Astroquarkae discuss the formation of White Dwarfs and Planetary Nebulae, what they have to do with each other, planets, and the price of tea in China (answers: lots, something superficial, and nothing at all). Also in this episode: nerd news, fishing advice, space trivia, and an imperial sponsor.  Walkabout the Galaxy is a fun and informative discussion...

Stripey Buggers 05.02.2017

The astroquarks welcome Brendan Byrne from WMFE 90.7 to discuss the some jaw-dropping images of Saturn's rings as Cassini begins working its way in towards its fateful plunge into Saturn on September 15, 2017. Along the way we'll dissect F/X no-no's in Star Wars and find out from Brendan if we're there yet. There = Mars, by the way, and time's a wastin'. 

A Space Odyssey 30.01.2017

One of these rocks is not like the other. One is a meteorite, and one is an asteroid, and we know that meteorites come from asteroids. So how come they look so different? The astroquarks discuss new research into ancient meteorites that shows how the tumultuous history of the asteroid belt is to blame. Plus charm quark Addie Dove points out that one rock is on the ground and one isn't, so there's...

The Hottest Year in a Row! 23.01.2017

Venus continues its record-setting warm streak now at over 1 billion years and counting, while the Earth just set its own modest record for the hottest year in the last 150 for the third record-setting year in a row. We've got a lot of work to do if we want to catch up with Venus. Speaking of Venus, something weird happened in its atmosphere that's probably the result of a gravity wave, not to be...

Walk About the Great Big Group of Stars 11.01.2017

In this piece of time of "Walk About the Great Big Group of Stars" we talk about two stars that will run into each other and make a big bright red thing five years from now. We also talk about two new big boxes with computers and stuff inside. The space team for our land will put these big boxes on two up- goers in years ahead to study things made of rock and also made of stuff that is like rock b...

The Fartological Cycle 04.12.2016

The astroquarks examine new observations of the rate of expansion of the universe and its consequences for Dark Energy, the mysterious force that is causing the expansion of the universe to accelerate. That, and what it would be like to live on Titan, a world where methane (natural gas) takes the place of water on the Earth: it rains methane into methane lakes, and it freezes out depending on the...

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