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
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