On 26 April 2026, it will be 40 years since the explosion at Unit 4 of the Chernobyl Nuclear Power Plant – the worst nuclear accident the world has known. In the early hours of 26 April 1986, a badly designed reactor, operated under intense pressure during a safety test, ran out of control. A powerful explosion and prolonged fire followed, releasing radioactive material across Ukraine, Belarus, Russia, with smaller quantities spewing across Europe.

In this episode of Physics World Stories, host Andrew Glester speaks with Jim Smith, an environmental physicist at the University of Portsmouth. Smith began his academic life studying astrophysics, but always had an interest in environmental issues. His PhD in applied mathematics at Liverpool focused on modelling how radioactive material from Chernobyl was transported through the atmosphere and deposited as far away as the Lake District in north-western England.

Smith recounts his visits to the abandoned Chernobyl plant and the 1000-square-mile exclusion zone, now home to roaming wolves and other thriving wildlife. He wants a rational debate about the relative risks, arguing that the accident’s social and economic consequences have significantly outweighed the long-term impacts of radiation itself.

The discussion ranges from the politics of nuclear energy and the hierarchical culture of the Soviet system, to lessons later applied during the Fukushima accident. Smith makes the case for nuclear power as a vital complement to renewables.

He also shares the story behind the Chernobyl Spirit Company – a social enterprise he has launched with Ukrainian colleagues, producing safe, high-quality spirits to support Ukrainian communities. Listen to find out whether Andrew Glester dared to try one.

In this episode of Physics World Stories, host Andrew Glester explores the fascinating hunt for pristine comets – icy bodies that preserve material from the solar system’s beginnings and even earlier. Unlike more familiar comets that repeatedly swing close to the Sun and transform, these frozen relics act as time capsules, offering unique insights into our cosmic history.

The first guest is Tracy Becker, deputy principal investigator for the Ultraviolet Spectrograph on NASA’s Europa Clipper mission. Becker describes how the Jupiter-bound spacecraft recently turned its gaze to 3I/ATLAS, an interstellar visitor that appeared last July. Mission scientists quickly reacted to this unique opportunity, which also enabled them to test the mission’s instruments before it arrives at the icy world of Europa.

Michael Küppers then introduces the upcoming Comet Interceptor mission, set for launch in 2029. This joint ESA–JAXA mission will “park” in space until a suitable comet arrives from the outer reaches of the solar system. They will deploy two probes to study it from multiple angles – offering a first-ever close look at material untouched since the solar system’s birth.

From interstellar wanderers to carefully orchestrated intercepts, this episode blends pioneering missions and cosmic detective work. Keep up to date with all the latest space and astronomy developments in the dedicated section of the Physics World website.

The latest episode of Physics World Stories takes you inside CUWiP+, the Conference for Undergraduate Women and Non-Binary Physicists, and the role the annual event plays in shaping early experiences of studying physics.

The episode features June McCombie from the University of Nottingham, who discusses what happens at CUWiP+ events and why they are so important for improving the retention of women and non-binary students in STEM. She reflects on how the conferences create space for students to explore career paths, build confidence and see themselves as part of the physics community.

University of Birmingham students Tanshpreet Kaur and Harriett McCormick share their experiences of attending the 2025 CUWiP+ event at the University of Warwick and explain why they are excited for the next event, set for Birmingham, 19–22 March 2026. They describe standout moments from 2025, including being starstruck at meeting Dame Jocelyn Bell Burnell, who discovered radio pulsars in 1967.

The episode provides practical advice to get the most out of the event. Organizers design the programme to cater for all personalities – whether you thrive in lively, social situations, or prefer time to step back and reflect. Either way, CUWiP+ offers opportunities to be inspired and to make meaningful connections.

Hosted by Andrew Glester, the episode highlights how shared experiences and supportive networks can balance the often-solitary nature of studying physics, especially when you feel excluded from the majority group.