StarTalk Radio – Cosmic Queries: Black Hole Universe
Host: Neil deGrasse Tyson
Co-Host: Baron Paul Mercurio
Air Date: September 9, 2025
Episode Overview
In this lively “Cosmic Queries Grab Bag” episode, astrophysicist Neil deGrasse Tyson and comedian (now “Baron”) Paul Mercurio answer listener questions about black holes, the nature of the universe, AI, nuclear power on the moon, the multiverse, and more. The blend of science, humor, and pop culture delivers both insight and entertainment, with discussions ranging from deep theoretical physics to relatable rants about public transit.
Key Discussion Points & Insights
1. How Much of the Universe Do We Really Understand?
Listener Question: Opal, Atlanta (15yo)
[05:09–08:45]
- Are there whole new types of science yet to discover, or is everything a branch of what we already know?
- Tyson explains that traditional science categories (physics, chemistry, biology) are artificial, made for convenience. Nature doesn’t draw these boundaries ([05:47]).
- NASA created "origins centers," bringing together different scientific fields to answer big-picture questions such as the origin of life.
- He argues new sciences can emerge when disciplines intersect, not simply as sub-branches ([06:51]).
- Tyson highlights neuroscience as a field still in its infancy and anticipates the development of AI may eventually foster new sciences—"But AI today only synthesizes what's already known or online" ([07:48]).
- He questions whether AI can originate completely new ideas, e.g., something as revolutionary as general relativity.
“Suppose you had a thought that no one ever thought of before and it’s not on the internet. Does AI have access to that thought? The answer is no.”
— Neil deGrasse Tyson [08:14]
2. Hawking Radiation & Black Hole Particle Pairs
Listener Question: Daumire da Silva, Brazil
[09:43–12:44]
- Does Hawking radiation favor the escape of antiparticles over particles from black holes?
- Tyson confirms the process is random; either particle of the pair can fall into the black hole ([10:44]).
- There is no evidence that antiparticles are favored over particles. The directions are random by quantum design ([11:09]–[12:44]).
- Paul and Tyson playfully comment on the familiarity of “BH” as short for black hole.
“You can just as easily have a regular particle going in as an antiparticle…he’s right to be suspicious.”
— Neil deGrasse Tyson [12:23]
3. Are Humans Closer in Size to an Atom or to the Universe?
Listener Question: Araya, Utah (12yo)
[16:02–19:29]
- Tyson reads from his upcoming book “Just Visiting This Planet,” providing a calculation in powers of ten ([16:34]).
- It takes only 15 factors of ten to get from human size to the nucleus of an atom, and 25 factors of ten to reach the edge of the visible universe.
- Therefore, we are physically closer to the scale of atoms than to the universe's edge.
“You are closer to the atoms in your toe. It’s only 15 powers of ten down, and it’s 25 powers of ten to the edge of the universe.”
— Neil deGrasse Tyson [18:50]
4. What’s the Best Power Source for a Moon Base?
Listener Question: Ethan Henning, Houston, TX
[21:24–28:13]
- Is it nuclear, solar, or something else?
- Tyson discusses “transportable” nuclear fission power plants, about the size of a large truck and capable of 100 kilowatts—enough to run around 100 hairdryers simultaneously ([23:50]–[24:52]).
- Such reactors can operate for 8–10 years without maintenance ([25:36]).
- Solar is possible, but the lunar night (about two weeks) and extreme cold hinder battery performance.
- Main threat: meteors, since the Moon has no atmosphere for protection—possible to bury reactors for safety ([28:13]).
- Tyson claims we’re only “years, not decades” from deploying such tech ([28:45]).
“A nuclear power generator about the size that I described, one of those would give you 100 kilowatts…That’s the energy level that NASA is looking at to send to the moon right now.”
— Neil deGrasse Tyson [23:01]
5. Hazards of Micro Black Holes for Interstellar Travel
Listener Question: Derek Evans, Connecticut
[29:00–33:13]
- Tyson explains smaller black holes evaporate (via Hawking radiation) much faster than larger ones—tiny black holes wouldn’t persist long enough to threaten spacecraft in flight ([30:07]).
- Space is extremely empty; even in the asteroid belt, distances between objects are vast ([31:29]–[32:45]).
- Thus, micro black holes pose no likely hazard to deep space travel.
“A tiny enough black hole will not last long enough for you to come upon it and then put your life at risk. Plus, we don’t expect there to be many of them. Space is really vast and really empty.”
— Neil deGrasse Tyson [31:29]
6. The Mysterious “Wow” Signal
Listener Question: Lily Rose, Virginia
[33:23–36:47]
- The “Wow” signal was a one-time radio burst detected in the 1970s—not sound, strictly a radio wave ([34:13]).
- Scientists never found a repeat of the signal.
- Tyson cautions against leaping to conclusions involving aliens; extraordinary claims require extraordinary evidence ([36:18]).
- Reminder: absence of an explanation is not evidence of any specific explanation.
“Just because you don’t know what you’re looking at doesn’t mean you know what you’re looking at. That needs to be a bumper sticker.”
— Neil deGrasse Tyson [36:34]
7. Are We Living Inside a Black Hole? The Multiverse and the Black Hole Universe Hypothesis
Listener Question: Conrad Dunphy, Portland, OR
[40:14–44:14]
- Tyson explains how recent findings (from the JWST—James Webb Space Telescope) of possible “rotation among an ensemble of galaxies” could hint at a universe with properties analogous to a black hole ([41:01]).
- In some multiverse theories, each black hole could create its own universe with potentially different physical laws.
- If universes have different physics, entering another could “collapse you into a pile of goo” ([42:25]).
- Only if another universe had identical physics could you safely travel there, but wormholes remain hypothetical.
“If there’s an infinite number [of universes], there’d be one with identical [physics].”
— Neil deGrasse Tyson [42:55]
8. Unexpectedly Mature Early Galaxies Seen by JWST—Alternative Explanations?
Listener Question: John Swiley, Athens, GA
[44:15–47:17]
- Are we seeing light from beyond our universe, or do rapid galaxy formations challenge our models?
- Tyson leans toward updating galaxy formation models rather than proposing radical explanations like “portals to other universes” ([45:47]–[45:59]).
- Invokes Occam’s Razor: don’t propose additional complexity unless necessary.
“If you have a complex hypothesis to explain something and someone else is walking around with a simpler explanation, the simpler explanation is probably correct.”
— Neil deGrasse Tyson [45:47]
9. Gravitons, Negative Gravity, and Wormholes
Listener Question: Dennis, Salisbury, IN
[47:19–49:14]
- Could we use interference (like in the double-slit experiment) to cancel out gravitational waves—or even gravity itself?
- Tyson explains LIGO is detecting changes in gravity, not static gravity—a necessary distinction ([48:21]).
- Negative gravity (required to stabilize wormholes in theory) has not been observed, but if wormholes exist, negative gravity must exist too ([48:49]–[49:14]).
“If we see a wormhole out there, somebody discovered negative gravity. That’s correct.”
— Neil deGrasse Tyson [49:14]
Notable Quotes & Moments
-
On New Sciences Emerging:
“Nature doesn’t draw those boundaries. We did.” — Neil deGrasse Tyson [05:47] -
On AI’s Current Limitations:
“Could AI come up with a thought that none of us have ever had nor have ever put it on the internet? There’s a limit to where AI can take us.” — Neil deGrasse Tyson [08:14] -
On Powers of Ten & Perspective:
“Adding the two sets of jumps reveals that the entire known universe spans about 40 powers of 10 in one direction.” — Read from Tyson’s upcoming book [18:32] -
Comic Banter:
“You need a nip and a tuck. You really do. That’s not even a real mustache…” — Paul Mercurio [07:32]
“If you see me on the street, please salute and curtsy.” — Paul Mercurio [49:39] -
On Speculative Theories in Astrophysics:
“Extraordinary explanations require extraordinary evidence.” — Neil deGrasse Tyson [46:09]
Timestamps for Major Segments
- [05:09] – New kinds of science, AI, and the future
- [09:43] – Hawking radiation and black holes
- [16:02] – Human size vs atom vs universe
- [21:24] – Power sources for the Moon
- [29:00] – Micro black holes and interstellar travel
- [33:23] – The “Wow” radio signal mystery
- [40:14] – Black hole universe hypothesis & multiverse
- [44:15] – JWST discoveries and galaxy formation
- [47:19] – Gravitons, gravity waves, and negative gravity
Tone & Style
The episode is hallmark StarTalk: equal parts insightful, humble, occasionally irreverent, and always accessible. Tyson is both patient and playful with listener questions. Mercurio brings comic relief and presses for relatable clarifications, making advanced cosmology both approachable and entertaining.
Conclusion
This “Cosmic Queries” episode is a fast-paced science variety hour, myth-busting and theorizing with both expertise and wit. Tyson and Mercurio engage beginner and advanced listeners alike, addressing cosmic mysteries and everyday curiosities about the universe, always with a dose of humor and humility. Audiences come away with a better understanding not only of black holes, AI, and the nature of inquiry itself, but of the wonder and uncertainty at the heart of science.
