Daniel and Kelly’s Extraordinary Universe

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Quantum Mechanics

Physics

Black Holes

Gravity

Parasites

Mars

Dark Matter

Evolution

Biology

Aliens

Big Bang

General Relativity

Evolutionary Biology

Sleep

Dark Energy

Particle Physics

Nuclear Power

Mathematics

Public Health

Artificial Intelligence

Scientists Daniel and Kelly cannot stop talking about our amazing, wonderful, weird Universe! Each episode is a fun, easy-to-understand, and in-depth explanation of topics in science, from particles to black holes to moon colonies to ecosystems to parasites and everything else in the Universe!

5.6k ratings

Publishes	Daily	Episodes	857	Founded	8 years ago
Number of Listeners		Categories	Natural SciencesPhysicsScience

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Guests Hosts Reviews Charts Talking Points

Latest Episodes

What if dark matter is more complicated?

Daniel and Kelly talk about a particularly quirky theory of dark matter that Daniel is searching for.

See omnystudio.com/listener for privacy information.

Yesterday • 44 min

Listener Questions #52

Daniel and Kelly answer listener questions about how AI is impacting math and physics, what we really know about the wood wide web, and what happens when matter annihilates.

See omnystudio.com/listener for privacy information.

6 Oct 2026 • 48 min

What is creativity? (featuring Dr. Moiya McTier)

Daniel and Kelly interview Dr. Moiya McTier about how we define and measure creativity, and the impacts of the modern world on creative pursuits. Check out her new book, Mothers of Invention.

See omnystudio.com/listener for privacy information.

1 Oct 2026 • 54 min • Popular

Supervoids

Daniel and Kelly explore the structure of the Universe and examine its emptiest places, making no effort to spare the scatological humor.

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29 Sep 2026 • 48 min • Most popular

Key Facts

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Contact Information

Podcast Host

Number of Listeners

Find out how many people listen to this podcast per episode and each month.

Similar Podcasts

People also subscribe to these shows.

Why This Universe?Dan Hooper, Shalma Wegsman

The Supermassive PodcastThe Royal Astronomical Society

Ask a Spaceman!Paul M. Sutter

Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and IdeasSean Carroll

SpaceTime with Stuart GaryStuart Gary

Recent Guests

Moiya McTier

Author and astrophysicist focusing on creativity and science communication

Author of Mothers of Invention

Episode: What is creativity? (featuring Dr. Moiya McTier)

Dr. Andy Sih

Distinguished professor in the Department of Environmental Science and Policy

University of California Davis

Episode: Do Animals Make Mistakes? (featuring Dr. Andy Sih)

Marcelo Wood

Professor and chair of the Neurobiology and Behavior Department at UC Irvine

University of California Irvine

Episode: Addiction (featuring Dr. Marcelo Wood)

Dr. Manuel Lerdau

Professor in the Department of Environmental Sciences at the University of Virginia; research director of the Morvin Sustainability Lab

University of Virginia

Episode: Listener Questions #47 - Plant Questions (featuring Dr. Manuel Lerdau)

Matt Keselman

Audio engineer and producer

Ocelot Audio

Episode: Sound (featuring audio wizard Mat Keselman)

Dr. Chelsea Wood

Associate Professor in the School of Aquatic and Fishery Sciences, University of Washington

University of Washington

Episode: Rat lungworm (featuring Dr. Chelsea Wood)

John Hutchinson

Professor of evolutionary biomechanics

Royal Society fellow

Episode: Listener Questions #44 - How fast can animals go, and how fast can animals grow? (featuring Dr. John Hutchinson)

Delair Mustafa

Listener who submitted questions about the early universe and GUT

New South Wales, Australia

Episode: What broke the grand unified force in the early universe?

Zach Weinersmith

Guest, co-host of related projects and creator

Weinersmith family/Weinoc

Episode: Listener Questions #42

Hosts

Daniel Weiner-Smith

Host with a background in physics and cosmology; co-host of the show.

Kelly Wienersmith

Host with parasitology and space research interests; co-host of the show.

Reviews

4.7 out of 5 stars from 5.6k ratings

Informative and Fun
Great chemistry between the two hosts. Interesting topics and a genuine thirst to educate.
Apple Podcasts
5
Cmot48
United States19 days ago
Fantastic, high information, low waffle science podcast without any tolerance for pseudo-science presented by two of the most engaging, funny, unpretentious hosts.
Podcast Addict
5
typhlosaurus
20 days ago
Great show well done
Podcast Addict
5
Airtime
23 days ago
Love
Love Daniel’s voice so calm and relaxing. Then there’s Kelly. Too much of a stark difference. Does Daniel have his own pod? Bring back Jorge?
Apple Podcasts
4
Pizzamonster817nomnom
United Statesa month ago
Great podcast
If you give this podcast a listen you won’t regret it
Apple Podcasts
5
MCS17171717
United Statesa month ago

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Listeners Say

Key themes from listener reviews, highlighting what works and what could be improved about the show.

Guests consistently praise the hosts' chemistry and ability to explain hard science clearly.

The show is valued for accessible but technically solid content.

Listeners enjoy a light, entertaining tone without sacrificing accuracy.

Quality guest expertise is often highlighted as a strength.

Audience notes the show can be addictive and highly informative.

Some critique the hosts' delivery as overly enthusiastic or noisy at times.

Chart Rankings

How this podcast ranks in the Apple Podcasts, Spotify and YouTube charts.

Apple Podcasts	#4	United States/Science/Natural Sciences
Apple Podcasts	#28	United States/Science
Apple Podcasts	#3	United Kingdom/Science/Natural Sciences
Apple Podcasts	#4	Canada/Science/Natural Sciences
Apple Podcasts	#24	Canada/Science
Apple Podcasts	#32	United Kingdom/Science

Talking Points

Recent interactions between the hosts and their guests.

Listener Questions #51

Q: Is free will compatible with relativity, and how do different observers affect the present moment?

Free will can exist; SR implies there is no single universal now, but this does not eliminate the possibility of choice within locally causally connected events, and quantum mechanics can introduce probabilistic outcomes that preserve some notion of agency.

Listener Questions #51

Q: What is the 'block universe' idea and does special relativity imply it?

Special relativity does not require a block universe, but it is compatible with it in the sense that different observers see different slices of a four-dimensional space-time; however, the reality of the future is not fixed by SR alone, and quantum mechanics allows probabilistic outcomes.

Listener Questions #51

Q: Does Lincoln's question about light always moving at speed C near a black hole violate special relativity?

The hosts explain that the velocity of distant objects in curved space isn't well defined; locally, light always travels at the speed C, but global velocity between distant points becomes a coordinate-dependent concept due to curvature.

Listener Questions #50

Q: Hi Daniel and Kelly. I was wondering about dialects of scent in animals and whether there are dialects across populations of the same species.

The hosts explain three main ideas: environmental factors like humidity and temperature can shape scent signals, genetic drift can create population-specific scent profiles, and microbes can alter scents in a way that leads to recognizable dialects; studies on otters showing spraint dialects and bats with forehead glands illustrate these concepts, and behavioral tests suggest females may prefer scents from their own colony.

Do Animals Make Mistakes? (featuring Dr. Andy Sih)

Q: Do animals ever make mistakes, and how do we define a mistake in the wild?

Mistakes are understood as outcomes that deviate from the optimal decision given uncertainty and partial information; sometimes a 'mistake' is simply the result of a risk-reward trade-off where the best available choice still leads to harm due to imperfect knowledge or changing conditions.

Audience Metrics

Listeners, social reach, demographics and more for this podcast.

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Frequently Asked Questions About This Podcast

What is This Podcast about and what kind of topics does it cover?

A duo of science communicators explore a wide range of topics across the natural world and the cosmos, blending approachable explanations with playful humor. Episodes often mix physics and astronomy with biology, ecology, and parasitology, and they frequently invite expert guests or field listener questions to illustrate complex ideas in accessible ways. A notable strength is translating high-level science into practical takeaways and vivid, memorable demonstrations, while maintaining a warm, conversational vibe that keeps even dense subjects engaging for curious listeners. The show appears to welcome diverse specialists and emphasizes clear distinctions between theory and evidence, making it a solid fit for listeners who enjoy deep dives t... more

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Which podcasts are similar to this podcast?

These podcasts share a similar audience with this podcast:

1. Why This Universe?
2. The Supermassive Podcast
3. Ask a Spaceman!
4. Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and Ideas
5. SpaceTime with Stuart Gary

How many episodes of this podcast are there?

this podcast launched 8 years ago and published 857 episodes to date. You can find more information about this podcast including rankings, audience demographics and engagement in our podcast database.

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What guests have appeared on this podcast?

Recent guests on this podcast include:

1. Moiya McTier
2. Dr. Andy Sih
3. Marcelo Wood
4. Dr. Manuel Lerdau
5. Matt Keselman
6. Dr. Chelsea Wood
7. John Hutchinson
8. Delair Mustafa

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