Unexpected Elements

Chernobyl: 40 years later

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

The ribbiting science of frogs

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

Is everyone accounted for?

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.

Putting science on the map

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

A bumper edition

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