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

The Interstellar Interloper and the Ravenous Black Hole 28.05.2018

It may sound like the title of an astroquark's sex tape, but we actually do have news about a potentially new long-term resident of the solar system captured from another planetary system, and Top astroquark Jim Cooney tells us all about a black hole gobbling up so much stuff that it's the brightest object in the universe! Honorary "Bottom" astroquark Dr. Zoe Landsman joins us to discuss these odd...

Does Mars Have a Chewy Center? 13.05.2018

We all know Mars is crunchy on the outside, but does it have a chewy center? The NASA Mars InSight mission is en route to the red planet to answer that question. The astroquarks talk about InSight's science and instruments, Han Solo, and Richard Feynman in another wide-ranging episode of Walkabout the Galaxy!

Chasing New Horizons with David Grinspoon 01.05.2018

Check out our first literally-titled episode! David Grinspoon, co-author of "Chasing New Horizons", the behind-the-scenes story of the Pluto mission, joins the astroquarks to dish on Pluto the planet, space exploration, Carl Sagan, and Mickey Mouse's dog! 

Danger Astroquarks! 14.04.2018

The astroquarks remember Yuri Gagarin's historic first flight in this episode before zooming off to the galactic center to see what's what with the discovery of thousands of black holes packed into the region. Then they zoom out to the galactic halo for a quick distance check on a globular cluster. Hopefully they won't get lost in space!

I Think I Stepped in Some Dark Matter 03.04.2018

What do Annihilation, Buckyballs, the Transiting Exoplanet Survey Satellite and an itsy-bitsy galaxy have in common? They're all topics for the latest walkabout the galaxy with the astroquarks. A small galaxy has been observed with essentially no dark matter (most are mostly made of the dark stuff). Paradoxically, this is very strong evidence for the existence of dark matter. Speaking of things th...

For Stephen Hawking 28.03.2018

The astroquarks discuss the late Stephen Hawking's first major breakthrough in astrophysics: radiation from black holes, now known as Hawking Radiation and what that means about what would happen if you through all the recordings of Walkabout the Galaxy into a black hole. UCF student and astronomer Anna Metke joins Josh and Jim to talk about telescopes near and far, and the giant radio telescopes...

Magnetic Ink Blot Test in Space 11.03.2018

Some things are hard to see, like black holes. In this episode of Walkabout the Astroquarks discuss a couple of new observations that help us see the earliest stars in the universe and the supermassive black hole at the center of our galaxy. Plus: Josh struggles to understand superhero movies, Jim provides the trivia, and Addie, as always, is Charm. 

Print Me a Space Base, Please 01.03.2018

The Astroquarks welcome Dr. Phil Metzger, expert on the use of local materials on the Moon, asteroids, and Mars, to tell us about the prospects for prospecting in space. Find out how to build your Moon home from the space dirt on hand, plus nerd news and space trivia!

The One Sponsored by Space Sex 20.02.2018

"Starman" in the Tesla Roadster is headed out past the orbit of Mars, and NASA has some cool new missions in the works for exploration of the solar system. One of those, Mars 2020, is the next high-tech rover for the red planet, and this one will be carrying with it an unusual rock sample. The astroquarks cover that and the two finalists for NASA's next New Frontiers mission, and we'll hear about...

I Could Swear I Left My Satellite in Orbit! 11.02.2018

It's a satellite theme on this episode, with a sparkly disco ball in space, a long-lost scientific satellite tracked down by an amateur astronomy sleuth, and space trivia about all the junk in space. Join the astroquarks for a quirky quarky tour of our solar system, and some new evidence about the earliest history of life on Earth.

The Old Stars Tell Tales 03.02.2018

Clues to dark matter may be buried in the relics of the oldest stars in the galaxies. The old stars probably formed when the dark matter did, so their motions are probably similar. The astroquarks discuss what this means for understanding that mysterious stuff, plus using X-rays to navigate spacecraft and yet another peculiar meteorite. Dr. Jonathan Kollmer joins the gang for these topics, as well...

The One About Bunburra Rockhole 23.01.2018

Thank you Australia for giving us a meteorite called Bunburra Rockhole, and not just because the name is endlessly fun to say, but also because it hints at an origin from a missing asteroid. In this episode of Walkabout the Galaxy, the Astroquarks also take a look at Saturn's youthful rings, the link between star formation and the supermassive black holes in the hearts of galaxies, and space trivi...

A Very Low Rumble in Space 08.01.2018

The astroquarks kick off the new year with a look at a clever and challenging new technique to detect gravitational waves created by supermassive black holes in the center of galaxies, and maybe even by the big bang itself. The waves make the Earth's position change, resulting in apparent changes in positions of things we look! Plus: astronomy predictions for 2018, nerd news, and space trivia. 

2017 - A Great Year for Space 28.12.2017

While terrestrial matters were frequently dark and depressing, 2017 was a banner year for the cosmos, or at least for our understanding of it. From Cassini's Grand Finale to LIGO's detection of neutron stars colliding, the astroquarks review the highlights of the year and a new story about a very old black hole from the dawn of the universe. A supermassive black hole formed before the universe was...

Antimatter from your Local Thunderstorm 11.12.2017

Antimatter, the stuff that lets the USS Enterprise fly about the galaxy is the topic of this episode of Walkabout the Galaxy because it's made in your garden variety thunderstorm. Lightning strikes have enough energy to drive nuclear reactions that produce antimatter electrons. Join the astroquarks for this and other heady topics such as the wobble of the Earth's axis in space trivia.

Fly Me To The Moon (of Saturn!) 30.11.2017

Disappointed that we don't have jetpacks and flying cars? Dr. Amanda Hendrix joins the Astroquarks to suggest an alternative: colonize Saturn's moon Titan, where a thick atmosphere and weak gravity mean we could all just fly like birds! Really! But, wait, there's more! Tune in to this episode of Walkabout for discussions of nearby moons and planets to colonize, space trivia and more.

Kronos the Planet Eater 18.11.2017

Stars have a voracious appetite, gobbling up most of the stuff in their immediate neighborhood, leaving just a few scraps to make planets. Sometimes, though, even the planets do not escape the stellar maw. In this episode of Walkabout, the astroquarks discuss a neat observation that shows a star likely gobbled several rocky worlds at some point in its past. Plus, help NASA name a Kuiper Belt Objec...

Rogue Asteroid! 08.11.2017

That asteroid is rogue, and that's hyperbolic, but not hyperbole. The astroquarks welcome Dr. Dan Durda to discuss the first detection of a planetary object passing through our solar system that definitively came from another planetary system. All those Star Trek episodes where there is a wandering planet or comet or asteroid in space are now officially validated! 

To Kilonova 01.11.2017

If two neutron stars collide in a galaxy 130 million light years away and no one has a gravitational wave observatory to detect it, does it make a sound? Well, that's a silly question, but it happened, and not only was this cosmic catastrophe observed in the high energy light it emitted, but the rippling of spacetime was detected as well. Astronomy now has two independent ways of observing energet...

I Left My Communicator on Sigma Iotia! 22.10.2017

The astroquarks welcome noted science blogger and author Dr. Ethan Siegel whose new book Treknology takes a look at the intersection of science and science fiction. While you may already have a tablet computer, warp drive is probably still a few years away. But Elon Musk may be sending missions to the moon in less time than it takes the U.S.S. Enterprise to complete its 5-year mission (so, less th...

SOFIA, Nobel and Kuiper - What's in a Name? 10.10.2017

The astroquarks welcome WMFE space reporter Brendan Byrne who recounts his flight on the SOFIA airborne observatory. They hen vent about how the Nobel Prize committee has unaccountably once again passed them over. Here about this year's winners in physics, and a discussion of the history of the Kuiper Belt in this episode's space trivia. 

OSIRIS-REx Gets the Gravity Assist and Scores! 04.10.2017

How exactly (and why) does a spacecraft get a "gravitational assist" from a planet en route to another planet? Where does that energy come from? The Astroquarks take a look at gravity assists and the OSIRIS-REx mission to grab some bits of a Near-Earth Asteroid and bring them back to Earth. Plus, the field of gravitational wave astronomy expanded now with the detection of a new black hole collisio...

To Be, Cassini, Or Not To Be 27.09.2017

Josh recounts experiencing the end of the Cassini mission and recalls more than a quarter century of involvement with the project in this episode. Then the astroquarks take a look outward toward our galaxy and its retinue of dwarf galaxies and what that may say about how typical, or not, the Milky Way is in the grand scheme of things. All that plus Cassini trivia, nerd news, and a meteorological s...

Florence and the LIGO Machine 17.09.2017

Asteroid Florence with her two mini-moons pays a visit to the Earth, while Tabby's Star continues to mystify with its unpredictable fluctuations in brightness. The astroquarks also cover the latest LIGO rumors about the detection of neutron star collisions, expanding the realm of gravitational wave astronomy. Plus Nerd News and Space Trivia!

Are Those Diamonds on Uranus? 07.09.2017

New experiments have created diamonds in the conditions expected in the interiors of Uranus and Neptune. Former Top Astroquark Tracy Becker joins Josh, Addie and Jim to discuss diamond rain deep in the atmospheres of these giant planets. Join the astroquarks for nerd news, space trivia, and a bit of planetary science for good measure.

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