Gravothermalizing and Baby Black Holes

Gravothermalizing and Baby Black Holes

Author: Joshua Colwell, Adrienne Dove, and James Cooney December 4, 2025 Duration: 46:48

There's a new funky proposal for small black holes in the early universe, and another potential dark matter candidate. Learn about cannibal stars and much more, together with double trivia and space news with your friendly neighborhood astroquarks.


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
Supernovas and Mass Extinctions [not-audio_url] [/not-audio_url]

Duration: 49:04
A survey of nearby stars establishes the rate of supernovas in our general neighborhood. Evidence indicates we had nearby stellar explosions at the times of two mass extinctions. Those supernovas may have decimated the o…
Life on Hycean Worlds, Interstellar Debris, and Dark Matter Survey [not-audio_url] [/not-audio_url]

Duration: 43:38
If there are Hycean worlds and if they have a certain kind of microbial life and if there is enough of it, JWST might be able to see the chemical products of that in the planet's atmosphere. We take a look at that, debri…
Are We Inside a Black Hole? [not-audio_url] [/not-audio_url]

Duration: 51:43
There are exciting new observations from recent lunar missions, a possible chunk of the Moon keeping us company, and an intriguing observation supporting the theory that the entire universe is inside a black hole! Get in…
Oort Cloud Spiral, the Color of Mars, and a New Dwarf Galaxy [not-audio_url] [/not-audio_url]

Duration: 41:15
We take a look at the formation and structure of the Oort cloud of comets which is spherical at large distances but has a spiral structure in its inner regions. And, after all this time, there's a surprising twist on the…
Did You Quipu? [not-audio_url] [/not-audio_url]

Duration: 36:31
Lunar exploration continues to accelerate, and there's a new longest "structure" in the universe. Quipu is a quasi-alignment of clusters of galaxies stretching over 1 billion light years. Structure is in cynical quotatio…
Hubble Tension Won't Go Away But Some Exoplanets Do [not-audio_url] [/not-audio_url]

Duration: 42:04
The more measurements we make of the expansion of the universe, the more it seems as though Hubble Tension is not a problem with our data but a problem with our understanding of the expansion of the universe. We'll talk…
Exocomets, Io, and the Great Dimming of T Tauri [not-audio_url] [/not-audio_url]

Duration: 44:21
Juno reveals a surprise about the interior of Jupiter's volcanic moon Io, and the OG young variable star T Tauri is getting ready to fade from view thanks to its dusty neighbors to the south. Speaking of dust, that's wha…
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…