Location:
United States
Description:
Dr Karl's a curious optimist – a great combination for a science lover. Join him and his guests for weird facts, amazing conversation and remember, it's never too late for a happy childhood. https://drkarl.com/
Language:
English
Episodes
Dumb Stuff In Space with Assoc. Prof. Michael Brown (471)
4/25/2026
We're living through the great Space Boom and with great innovation comes a lot of whacky ideas... Astronomer and Associate Professor Michael Brown from Monash Univeristy joins me to discuss stupid things in space.
The conversation dives into some of the more bizarre and ambitious ideas circulating the space industry, from firing villians and radioactive waste in to the sun to deploying giant orbital mirrors to light up Earth's dark side. Brown breaks down why many of these concepts are far less practical then they sound. With over 15,000 satellites cirlcing earth, Brown also examines the promises and downsides of mega-constellations like Starlink, including how they operate and the challenges they pose for astronomers and the environment.
It's a fascinating and critical peek in to the intersection of innovation, risk, and imagination in the new space age.
Duration:00:33:08
Using Soundwaves To Measure The Sun with Prof. Connie Aerts (470)
4/18/2026
In this episode I sit down with Prof. Conny Aerts, a pioneering mathematician and founding figure of astroseismology, who reveals how scientists are "listenting" to stars to understand what's happening deep inside them. From oscillating stars to solar "sunquakes", she explains how sound waves can measure the Sun's size, age and activity.
Beyond the science, she shares her remarkable journey from a small rural town in Belgium where she had to attend an all-boys school, the only school near her family home. She was expected to become a seamstress but Conny's dreams were outer-worldly, leading her on a path toward becoming a highly acclaimed asteroseismologist.
Duration:00:31:07
How To Die in the 21st Century with Dr. Hannah Gould (469)
4/11/2026
We're scared to say the D word! But why is talking about death such a taboo? Dr. Hannah Gould, a cultural anthropologist at the University of Melbourne, joins me to discuss the topic - we usually avoid talking about - in the wake of her new book 'How To Die in the 21st Century'.
The discussion dives in to the modern experience of dying, from the pressures of having a 'good death' to the reality of overly medicalised, 'prolonged dwindling'. Hannah unpacks how death isn't just biological but also cultural and legal, raising the question: When does death officially occur?
The conversation is an invitation to rethink death - not as something to fear, but as something we can approach with openness, intention, and maybe even a sense of celebration!
Duration:00:30:34
How Two Students Fixed the Focus of James Webb from Earth with Prof. Peter Tuthil, Dr. Louis Desdoigts & Max Charles (468)
4/4/2026
When a problem with the James Webb Space Telescope left its images frustratingly out of focus, the solution wasn't fixed in space... it was fixed from Earth. At the University of Sydney, PhD students Dr. Louis Desdoigts and Max Charles spent two years rewriting and refining code to recalibrate a critical instrument designed by Professor Peter Tuthill: the Aperture Masking Interferometer.
Their breakthrough sharpened the telescope's infrared vision unlocking clearer views of distant worlds, including volcanic activity on Io, one of Jupiter's moons. In a fitting tribute, the pair even got matching tattoos of the hardware they helped fix!
Not only did their work restore clarity to one of humanity's most powerful observatories, it also saved NASA the immense cost and impossibility of repairing the telescope in space.
Duration:00:28:59
Forensic Science: Fact, Fiction, and Failure with Dr Linzi Wilson-Wilde and Hannah Jarman (467)
3/28/2026
This episode features Dr. Linzi Wilson-Wilde and Hannah Jarman discussing the realities of forensic science beyond shows like CSI. Through cases such as the Phantom of Heilbronn case and Lindy Chamberlain-Creighton, they explore how flawed evidence and forensic myths have contributed to wrongful convictions. They also examine common misconceptions around techniques like bite mark analysis, fire investigation, and glass evidence. The conversation emphasises the importance of approaching forensic science holistically, recognising it as just one piece of the broader investigative puzzle.
Duration:00:26:34
The Wellness Woo Economy with Kate Thomas (466)
3/21/2026
Pharmacist and science communicator Kate Thomas shares how a viral debunking video launched her into the world of online health education. In this episode, we explore the booming "wellness woo" economy and sift through the weeds on why misleading short-form content spreads so easily and the risks of unregulated wellness influencers. Kate breaks down the truth about supplements, the power of placebo, and why accessible, personalised health advice is so hard to find online. She also highlights the important role pharmacists play in helping consumers make informed choices.
TikTok & Instagram: @PrescribeOrPass
Linkedin: Kate Thomas
Duration:00:30:52
The Hidden Health Impact of Microplastics with Prof. Michaela Lucas (465)
3/14/2026
Professor Michaela Lucas, an Immunologist and Immunopathologist researching the health impacts of plastics, joins me to explore what microplastics and plastic-associated chemicals may be doing inside our bodies. We discuss how compounds like bisphenols and phthalates can act like hormone-mimicking molecules, the evidence linking plastic exposure to developmental and fertility concerns, and why some estimates of microplastics in the body may have been overstated.
Professor Lucas also shares insights from her ongoing study in Perth examining how everyday exposures, particularly ultra-processed foods packaged in plastic, may contribute to microplastics in the body. Listeners can subscribe to receive the study results when they're released via www.uwa.edu.au/projects/the-perth-trial.
Linkedin: @prof-michaela-lucas/
Duration:00:31:44
Deeepfakes Online and The Future of Truth with Dr. Anna Broinowski (464)
3/7/2026
I'm joined by Dr. Anna Broinowski - Senior Lecturer and Director of the Master of Film and Screen Arts at Sydney College of the Arts, University of Sydney - to unpack the rise of deepfakes and synthetic media.
We discuss the emergence of deepfake pornography in 2017, the fact that around 90% of deepfake content targets women and girls, and the growing use of AI in propaganda. From political manipulation to fake ads impersonating me (!), this episode explores how deepfakes are eroding trust, and what that means for the future of media, filmmaking and truth more broadly.
Duration:00:33:18
The Rise In Nitrous Misuse with Assoc. Prof. Angela Chiew (463)
2/28/2026
Nitrous oxide (better known as "laughing gas") is widely used in medicine as a safe anaesthetic and pain reliever. It's also found in whipped cream canisters and even used in car engines. But Angela Chiew, toxicologist and Associate Professor at UNSW, joins me to set the record straight: the growing recreational misuse of this easily accessible gas is causing serious long-term harm, including nerve damage, cognitive damage, weakening of the spinal cord and mobility impairments.
Cases of misuse are rising globally, likely driven by how easy it is to legally purchase the drug in many countries. This episode unpacks the hidden dangers behind a gas many once thought was just a harmless high.
Linkedin: Angela Chiew
X: AngelaChiewA
Duration:00:27:55
Will AI Take Our Jobs? Part Three of the Great AI Safety Debrief with Dr. Petr Lebedev (462)
2/21/2026
In the final episode of the Great AI Safety Debrief series with Dr. Petr Lebedev, we discuss job eradication, AI alignment and the rise in cases of AI deceiving humans. Petr unpacks ideas like AI scheming, situation awareness, parasitic relationships between humans and machines, and even the possibility of AI developing belief systems of its own. We end by zooming out to existential risk, Alan Turing's early warnings, and why aligning AI with human values may be one of the most difficult (and urgent) challenges humanity must face.
Linkedin: Petr Lebedev
palisaderesearch.org/
Duration:00:28:44
Is AI Outsmarting Us? Part Two of the Great AI Safety Debrief with Dr. Petr Lebedev (461)
2/14/2026
In part two, Dr. Petr Lebedev and I dive deeper into how modern AI systems are grown, not programmed, and the emergence of Shutdown Resistance. We explore AI performance in math and coding competitions, the rapid evolution of ChatGPT models, and why companies are already letting AI write the majority of their code. Petr explains how huge investements globally are pushing these systems forward faster than we can fully understand or control.
The final episode in this 3 part series drops next week!
Linkedin: Petr Lebedev
palisaderesearch.org/
Duration:00:23:54
The Great AI Safety Debrief with Dr. Petr Lebedev - Part One (460)
2/7/2026
Intelligence is emerging from sand and less than 1% of the population seems to care!
Physicist and science communicator Petr Lebedev joins the podcast following his SXSW talk to explore why AI is advancing so fast, and why that should make us pause. From completing a PhD in physics and writing for Veritasium to leading science communication at Palisade Research, Petr steps in to bring some clarity to the weird, wild, and worrying sides of AI.
Did you know that no one truly understands how large language models actually work? We go deep on misaligned systems, humanoid and dog robots, and why many experts believe AI could pose a serious global risk. Is AI our greatest tool — or something we're slowly losing control of? This conversation is big, so we've split it into three parts. Part two drops next week.
Duration:00:24:10
The Milky Way's Mysterious Glow with Prof. Geraint Lewis (459)
1/31/2026
A mysterious glow from the centre of the Milky Way has scientists intrigued. Astrophysicist Geraint Lewis explains how this gamma-ray excess, first detected in 2009, could be evidence of dark matter particles interacting deep in our galaxy. With dark matter believed to make up a vast, invisible halo that holds galaxies together, uncovering the source of this glow may bring us closer to understanding what the universe is really made of.
www.geraintflewis.com/
Linkedin: geraint-lewis-4a499b1
Duration:00:32:28
Staying Safe Online Part 2 with Troy Hunt (439) [REPEAT]
1/17/2026
In part two with Online Safety Consultant Troy Hunt (Have I Been Pwned), we unpack the risks of online age verification in light of Australia's social media ban, including the personal data (often times photos or government documents) sites may demand, and how these security practices can be questionable.
Troy explains why we should be thinking more about data minimisation and the dangers of unnecessary data retention. We go through the safest multi-factor authentication methods, from SMS to physical keys, and Troy shares a personal phishing story, reminding us that no-one is immune to hacking thanks to increasingly sophisticated phishing techniques.
https://haveibeenpwned.com/
Linkedin: Troy Hunt
Duration:00:27:01
The Human Side of Misinformation Part 2 with Assoc. Prof. Marian-Andrei Rizoiu (445) [REPEAT]
1/10/2026
In part two, Associate Professor Marian-Andrei Rizoiu from the University of Technology Sydney explains how misinformation and toxic online cultures spread. We dive into the "manosphere pipeline" targeting boys as young as 10, its real-world impacts on schools and families, and how it can escalate into radicalisation.
Rizoiu outlines his team's six-stage pipeline - from passive curiosity to active involvement - and why simply giving people facts doesn't solve the problem. Instead, this is a human challenge, and his lab is exploring new ways to diffuse and counter online misinformation before it turns dangerous.
Linkedin: Marian-Andrei Rizoiu
Duration:00:25:53
Rethinking Laundry for the Planet With Dr Holly Kaye Smith (430) [REPEAT]
1/3/2026
Most of us throw our clothes in the wash without a second thought, but what if that habit is doing more harm than good? In this episode, Dr. Holly Kaye-Smith, social change expert and communications specialist, challenges the way we think about cleanliness, climate action, and everyday laundry.
From surprising stats (over 90% of washed clothes aren't even dirty!) to the hidden environmental cost of every wash cycle, we dive into the myths, microplastics, and mindsets that shape our laundering routines. Holly shares practical refreshing techniques that save water, and why she recommends everyone have a "rewear chair."
Connect with Dr Holly Kaye Smith on Linkedin
Instagram - www.instagram.com/drhollyphd/
Youtube - www.youtube.com/@drhollyphd
Duration:00:21:44
Climate Overshoot: The World Beyond 1.5 Degrees with Dr. Andy Reisinger (458)
12/26/2025
In this episode, we speak with Dr. Andy Reisinger, an internationally recognized expert in climate change science and policy, with a focus on mitigation and agricultural emissions. Together, we unpack the concept of climate overshoot - why the world is set to exceed the 1.5°C warming limit within the next five years, and what that means for people and the planet. Dr. Reisinger explores whether the damage already done is reversible, what it would take to get back on track, and, hypothetically, the bold actions he would take if he had the power to drive real societal change to combat climate change.
Linkedin: Andy Reisinger
Duration:00:30:01
More Everyday Consumer Good Facts Part 2 with Ashley Iredale (457)
12/20/2025
Consumer technology expert Ashley Iredale returns for part two, bringing more surprising facts about everyday household appliances. We break down why your fridge actually contains more heaters than coolers, demystify the Energy Star rating system, and settle the debate on whether front-loading or top-loading washers are more efficient at cleaning clothes.
Duration:00:17:40
Cooking Dinner In Your Dishwasher?! & Other Fun Facts with Ashley Iredale (456)
12/13/2025
This episode i'm joined by Ashley Iredale, a consumer technologist and content producer whose winding career through industrial design has armed him with a trove of quirky tips and practical wisdom.
Ashley breaks down the real efficiency of hand-washing versus dishwashers, explains how a dishwasher can double as an oven, and settles the age-old question of how toilet paper should hang. We also dig into his non-linear career journey and how it led to his deep well of surprising insights. There was so much to cover that Part Two lands next week!
Linkedin: Ashley Iredale
Duration:00:18:35
The Discovery That Changed Astrophysics with Prof. Dame Jocelyn Bell Burnell (455)
12/6/2025
In this episode, I'm joined by the legendary Dame Susan Jocelyn Bell Burnell - the pioneering astrophysicist who discovered pulsars, launching an entirely new field of astrophysics.
She began her PhD searching for quasars, but soon noticed a strange, repetitive signal appearing night after night - so peculiar she jokingly labelled it LGM ("Little Green Men"). That signal would become one of the most important astronomical discoveries of the century, though the credit and Nobel Prize were controversially awarded to her supervisor.
Dr Bell Burnell also shares why she donated $4.3 million of her own prize money to support underrepresented researchers in physics, especially women and girls, and the work she's doing to make the field more inclusive.
We dive into her views on religion, her life in science since that landmark discovery, and her mission to help more young women pursue careers in physics.
Duration:00:32:01
