The Milky Way's Mysterious Glow with Prof. Geraint Lewis (459)

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

In this episode, I'm joined by Professor Clare Collins, Australian dietitian and Professor of Nutrition and Dietetics at the University of Newcastle. Clare is my go-to expert when it comes to all things nutrition, and today she's here to unpack the often confusing world of processed and ultra-processed foods. We dive into what really separates the two, explore the role of additives, emulsifiers, and flavour enhancers, and discuss how some of these ingredients, designed to make foods more appealing, may be doing our health more harm than good. Plus, she shares practical, no-nonsense tips to help you make smarter choices next time you're wandering the grocery aisles. Check out Clare's free online resource, No Money No Time, for simple, budget-friendly recipes and nutrition advice - nomoneynotime.com.au/ Follow Clare on X: @ProfCCollins and LinkedIn: Clare Collins.

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

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

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    

In this episode, we speak with Dr. Andy Reisinger, an internationally recognised 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

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.

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

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.

This week I'm joined by John Staton, one of Australia's leading sunscreen-testing experts, to unpack the big headlines surrounding sunscreen safety. A recent Choice report revealed that 16 out of the 20 tested sunscreen products failed to meet their advertised SPF rating by a significant figure. John helps us to understand what is really going on. He breaks down how sunscreens actually work and the science behind SPF testing and why so many products fell short.