Unexpected Elements

On 26th April 1986, Reactor 4 at the Chernobyl nuclear power plant in Ukraine exploded, releasing vast amounts of radiation. Now, 40 years later, it remains the worst nuclear accident in history. Using the Chernobyl anniversary as a starting point, this week the Unexpected Elements team find out about the weird life thriving at the site of the nuclear reactor. Next up, we discover how radioactive isotopes can help doctors diagnose cancer.We then turn our attention to ‘gamma gardens’, which were developed by scientists in the 1950s and 1960s to investigate the impacts of radiation on plants. Professor Helen Anne Curry, from the Georgia Institute of Technology, joins us to reveal more. All that, plus many more Unexpected Elements. Presenter: Marnie Chesterton, with Andrada Fiscutean and Dr Emmanuel Samani Producers: Alice Lipscombe-Southwell, with Margaret Sessa Hawkins and Georgia Christie

In 2025, Russian-born scientist Kseniia Petrova picked up some spliced frog embryos from a laboratory in France and brought them back to the USA to aid her research into ageing and cancer. She was detained by the United States Immigration and Customs Enforcement (ICE), charged with smuggling and had her visa revoked. Now though, a judge has ruled that the scientist’s visa was wrongly cancelled.Inspired by this story, the Unexpected Elements team find out how embryos and sperm behave in space. Next, we discover that embryos can regenerate limbs, and new research could help us unlock those skills as adults. We also reveal the unexpected link between frogs and pregnancy tests, and find out about a devastating fungus that’s wreaking havoc on amphibians. And don't miss probiotics for coral reefs, dessert stomachs and the weird physics of time. All that, plus many more Unexpected Elements. Presenter: Marnie Chesterton, with Katie Silver and Camilla Mota Producers: Alice Lipscombe-Southwell, with Ella Hubber and Georgia Christie

This month, India began the immense undertaking of surveying its population of 1.4 billion people in the world’s largest ever census. Inspired by this huge task, the Unexpected Elements team explores some population science. First, counting – or miscounting – populations. The global human population may be much larger than previously thought as research shows counts may have missed those living in more remote areas. And we learn about the species stuck in a neverending “species limbo”, where they’ve gone unseen for decades but still can’t officially be declared extinct. Next, we’re joined by geneticist Dr Ambroise Wonkam, one of the researchers behind the Three Million African Genomes project, who tells us why sequencing more African genomes is the key to unlocking a wealth of vital genetics knowledge.Also, Mumbai’s out of tune musical road, how we know volcanoes are extinct, and the weight of the internet. All that, plus many more unexpected elements.Presenter: Caroline Steel, with Chhavi Sachdev and Candice Bailey. Producers: Lucy Davies, with Ella Hubber, Imy Harper and Georgia Christie.

China’s ambitious underwater mapping operation takes us on a voyage into the depths of ocean and map science.We look at what a network of underwater microphones can tell us about underwater geography, noisy ships, and whale conversations, and how it took nearly 300 researchers working together to map 140 000 neurons in a fruit fly’s brain.Then, we are joined by biogeochemist and author Karen Lloyd, who tells us about the long-lived microbes living deep in the crust below the sea floor, how they survive for 100 000 years, and what their mysterious existence tells us about life and evolution. And forget sunken treasures – we will talk about the valuable, potato-sized mineral nodules that grow on the sea floor, and the pros, cons and current legality of mining them. Plus – how dolphins can help us track down abandoned undersea explosives.All that and even more unexpected elements.Presenter: Marnie Chesterton, with Katie Silver and Tristan Ahtone Producers: Ella Hubber, with Lucy Davies and Georgia Christie

Japanese pedestrians have been forcefully colliding with each other in a spate of butsukari otoko – or ‘bumping man’ – incidents and the Unexpected Elements team has been inspired to investigate some bumpy science.First, what does your heart desire? Well, at a cellular level, the perfect match! We hear how your heart is built by cells going speed dating. Then, we discuss how birds avoid in-flock collisions, and we learn all about mesmerising murmurations.Next, we’re joined by science journalist and author Robin George Andrews, who tells us about NASA’s mission to avoid a city-killing disaster by bumping into an asteroid before it can bump into us.Also, a colourful question about migraines, a surprising new treatment for them, and the scientists who took antimatter for a test drive.All that, plus many more Unexpected Elements.Presenter: Marnie Chesterton Producers: Sophie Ormiston, with Ella Hubber, Katie Tomsett, Imy Harper and Lucy Davies

After the end of a near 17-year legal battle between popstar Katy Perry and fashion designer Katie Perry, the Unexpected Elements team has been inspired to explore the question at the heart of the case – what's in a name? First, we hear how marmosets use their calls as a way of naming which friend they’re talking to. Then, we discover why a phenomenon known as auditory pareidolia means you can’t necessarily believe your ears.We're then joined by David Kaiser, professor of physics and history of science at the Massachusetts Institute of Technology, who explains just how hard it is to put physics into words. Also, the disappearance of indigenous languages, the law for naming laws, and where did all our hair go?All that, plus many more Unexpected Elements.Presenter: Marnie Chesterton with Andrada Fiscutean and Michael Kaloki Producers: Imy Harper, with Lucy Davies and Sophie Ormiston

With this year’s Oscars on the horizon, and vampire film Sinners nominated for a record-breaking 16 awards, the Unexpected Elements team sinks their teeth into some blood-sucking science.First, we discover that Vlad the Impaler, the Romanian prince who inspired Dracula, may have not only had blood on his hands, but also in his tears. We also hear about a woman in Guadeloupe with the world’s newest and rarest blood type.We’re then joined by Dr Naomi Ewald from the UK’s Freshwater Habitats Trust who tells us all about nature’s little bloodsuckers – leeches – and why their use in medicine is not just a practice consigned to the history books.Also, the gravity-defying gecko of the Gambia, how close are we to producing artificial blood, and the Patagonian dinosaur that looks like a judgemental chicken.All that, plus many more Unexpected Elements.Presenter: Marnie Chesterton Producers: Ella Hubber, with Sophie Ormiston, Lucy Davies and Imy Harper

The Hindu festival of Holi has the Unexpected Elements team delving into the science of colour. First up, forget chicken and egg, we bring you a whole new controversy of which came first: colour or colour vision? Then, we learn how a new development in infrared contact lenses could extend our range of vision and help people with colour blindness. We’re then joined by marine biologist Roger Hanlon who explains how octopuses are great at changing tones, even though they can’t appreciate the colours that they make. Plus, what’s orange, cream, 5,000 years old and worryingly resistant to most of our common antibiotics? And why does reading on dark mode leave one listener seeing things? All on this week’s Unexpected Elements. Presenter: Marnie Chesterton, with Andrada Fiscutean and Chhavi Sachdev Producers: Imy Harper, with Ella Hubber and Lucy Davies

A dip in global cocoa prices got the Unexpected Elements team wondering about chocolate science. First, we look at how the microbial communities in cocoa beans fine tune the taste of chocolate. Also, could table sugar help us detect the missing bits of the universe? We look at how three elements in sugar were used in the hunt for dark matter. We’re then joined by Professor of Experimental Psychology Charles Spence, who explains the myriad ways that taste can be influenced – including the shape and name of chocolate, and even the music we listen to as we eat it. Plus, we hear about the rediscovery of a moth in South Africa that was lost to science for 150 years.And finally, why we cry when we chop onions and the insects that pollinate the cocoa tree. That’s all on this week’s Unexpected Elements. Presenter: Marnie Chesterton, with Candice Bailey and Sandy Ong Producers: Sophie Ormiston, with Lucy Davies, Tim Dodd, Imy Harper and Margaret Sessa-Hawkins

Identical twins on trial for murder in France have left forensic experts unable to answer the question of which one pulled the gun’s trigger. With both having the same DNA, it got the Unexpected Elements team thinking, when do identical twins cease to be identical?First, we look at how scientists have been confronting the possibility that they might soon be able to create an evil twin to life itself - mirror life. Also, we hear why the ‘Tatooine planets’ which orbit twin stars are so rare in our galaxy.We’re then joined by professor of developmental psychology Nancy Segal, who explains why prosecutors should be able to distinguish between the French twins on trial. Plus, we hear how African farmers are struggling with a lack of data on pre-harvest crop loss.And finally, why gorse flowers smell like pina coladas, and how the use of DNA evidence in court can still come down to interpretation. That’s all on this week’s Unexpected Elements.Presenter: Marnie Chesterton, with Kai Kupferschmidt and Michael Kaloki Producers: Ella Hubber, with Lucy Davies, Sophie Ormiston, Imy Harper and Tim Dodd