Second Generation Black Hole Mergers and Solar System Chaos

Second Generation Black Hole Mergers and Solar System Chaos

Author: Joshua Colwell, Adrienne Dove, and James Cooney June 4, 2026 Duration: 46:34

Exquisitely detailed measurements of the ripples in spacetime from the mergers of black holes now show that some of these merging black holes were, themselves, created by an earlier black hole merging event. While this had been suspected to take place, we now have clear evidence of it. On a less dramatic scale but much closer to home, new simulations of the early solar system suggest the large population of moons of Uranus needed help from a now long lost fifth giant planet to survive. Join us for all this, space news, trivia, and a generally good time.


Ever wondered what it would be like to grab a coffee with a few planetary scientists who can’t help but find the humor in the cosmos? That’s the feeling you get with Walkabout the Galaxy. Hosted by Joshua Colwell, Adrienne Dove, and James Cooney, this isn’t a dry lecture from a distant lecture hall. Instead, it’s a lively, often funny conversation that feels like you’re right there with them, unpacking the universe’s latest headlines. Each episode digs into the newest and most fascinating discoveries in astronomy and space science, but the approach is grounded and genuinely curious. You’ll hear the hosts’ real excitement and occasional friendly debates as they translate complex ideas from recent papers or major missions into stories anyone can connect with. The tone is naturally irreverent, which makes the science stick, and their camaraderie turns each discussion into an engaging journey. Tuning into this podcast means getting a front-row seat to a casual yet deeply informative chat about everything from quirky asteroids to the profound mysteries of distant galaxies, all delivered with a warmth that reminds you why looking up at the stars is so compelling in the first place. It’s a perfect blend of solid science and natural comedy, making the vastness of space feel a little more like home.
Author: Language: English Episodes: 100

Walkabout the Galaxy
Podcast Episodes
Little Red Dots and Big Black Holes [not-audio_url] [/not-audio_url]

Duration: 44:32
The discoveries from the James Webb Space Telescope keep coming. After showing that galaxies formed far earlier than we thought, we now have a better understanding of what was going on in the early universe. Those little…
Kiss and Capture for Pluto and Charon and Dark Energy Remains Dark [not-audio_url] [/not-audio_url]

Duration: 46:03
Pluto and its largest moon, Charon, orbit each other with gazes lovingly fixed on each other, held in place by a romantic tidal attraction. But Charon's large size has always been difficult to explain. New simulations sh…
Quasi Particles, Pluto's Moons, and Cosmic Rays [not-audio_url] [/not-audio_url]

Duration: 45:25
We kick off 2025 with oddities from quasi particles, to cosmic rays, to the moons of Pluto. What has mass when it moves in one direction and doesn't when it moves in another direction? How do thunderstorms on Earth inter…
Mysterious Dark Comets [not-audio_url] [/not-audio_url]

Duration: 39:22
We know about extinct comets and active asteroids, but now we've got something in between: dark comets, whose orbits indicate cometary activity, but we can't see it! We'll get the scoop on these interesting objects, a fl…
Making Big Blobs is Hard [not-audio_url] [/not-audio_url]

Duration: 37:48
Top quark Jim Cooney explains why making big blobs is hard and how new observations are helping us understand how the universe made big immensely big blobs more commonly known as giant elliptical galaxies. Nature loves t…
Neutrino Fog and the Hunt for Dark Matter [not-audio_url] [/not-audio_url]

Duration: 43:44
It's a good news bad news story with the detection of the neutrino fog. This signal from solar neutrinos may confound our search for certain dark matter candidates, but at least we know our detectors are very, very sensi…
Not All Supernovae Are Created Equal [not-audio_url] [/not-audio_url]

Duration: 41:34
If you're speaking English, not Latin, do you really have to say "supernovae" instead of "supernovas"? Also, they are, in some sense, created equally: explosion of a white dwarf, but the outcomes are not all equal. You a…
Is There Another Belt of Comets? [not-audio_url] [/not-audio_url]

Duration: 42:02
New observations contradict earlier studies about the possibility of another belt of comets orbiting the Sun twice as far away as Pluto. We'll take a look at what's what in the outer solar system and also explore whether…
Trojan Asteroids Everywhere [not-audio_url] [/not-audio_url]

Duration: 28:14
Join Strange and Down quarks for a close look at Trojan asteroids, the forgotten asteroids of the solar system. NASA's Lucy mission is en route to take our first close look at these denizens of the outer solar system and…
Basin Instinct - Cosmological Structure and Edible Asteroids [not-audio_url] [/not-audio_url]

Duration: 45:09
We get a tour of our place in the grand cosmological scheme of things with new mapping of the local Basin of Attraction. Spoiler: also Jim's new stage name. And we explore the final frontier of In Situ Resource Utilizati…