Listener Dickson Mukisa from Uganda has been gazing up at the stars. But he’s not making wishes. He wants to know whether we can harness their energy, in the same way we do with our OWN star – the sun. After all, they may seem small and twinkly to us, but each one is a gigantic flaming ball of energy, with a power outputs averaging around 40 quadrillion kilowatt-hours per year – EACH! With somewhere between 100 and 400 BILLION stars in our own galaxy alone, that’s a lot of power! Can we get ‘solar power’ from stars that are such a long way away from earth? And what might we use it for?

Alex Lathbridge heads to the University College London Observatory, to peer through the eyepiece of an enormous telescope and see some stars for himself. Professor Steve Fossey explains just how much of the light energy of the stars reaches us on earth. In other words, how BRIGHT they are.

Once the starlight reaches earth of course, we have to capture it. Could traditional solar panels do the job? Alex meets Professor Henry Snaith from the University of Oxford, to find out about the future of photovoltaic technology, and why it could all be heading out to space.

Once in space, things start getting weird! What if we made an enormous fleet of solar panels, and put them all into orbit around a star, soaking up every last drop of that precious energy? That might sound like science fiction, but the idea has been around for decades. It’s called a Dyson Sphere, or Dyson Swarm. Swedish researcher at the Insitute for Future Studies, Anders Sandberg explains how we might be able to build one around a neighbouring star... in around 10,000 years or so.

But maybe it’s not all about light. Finally, Alex explores the mysterious, invisible energy of the ‘solar wind’, with Pekka Janhunen, Finnish physicist and inventor of the “E-Sail”, which might be able to harness the power of the stellar wind, too.

Presenter: Alex Lathbridge

(Image: Astronomer looking at the starry skies with a telescope. Credit: m-gucci via Getty Images)

No one really cares that CrowdScience listener Sam has a younger brother, but they do care about his sister. In fact, they’re fascinated by her. That’s because Sam and his sister are fraternal twins.

He’s been wondering all his life why he’s treated differently. Could it be cultural? Twins have long appeared in classical mythology, revered literature, and playful comedies—captivating artists and audiences alike across time and continents. Or is there something more scientific behind our fascination? Why are twins special?

Anand Jagatia investigates with Karen Dillon from Blackburn College in the USA, who says it’s more complicated. Over the years we have created stereotypes of who and what twins are. Our perception has been warped by history and pop culture. As an identical twin herself, she knows firsthand how stereotypes can shape a twin’s identity.

Philosopher Helena De Bres from Wellesley College in the USA believes these stereotypes play on human anxieties. Their similarities and differences are derived from their biology, maybe our genes have more of an influence over our personalities and behaviours than we like to think?

And Nancy Segal agrees, Director of the Twin Studies Centre at California State University in the USA. She has spent her career studying twins. She’s found that nearly every trait, whether it be behavioural or physiological, has a genetic component to it.

Anand is sure to leave you thinking that Sam, his sister and all the other twins across the globe, really are special!

Presenter: Anand Jagatia

(Image: Twin girls (8-10) wearing matching coats and pigtails. Credit: Jade Albert Studio, Inc via Getty Images)

Cycling is good for our health, good for the planet, and it can be an efficient way of moving around busy cities. But despite all the rational arguments for it, in most cities the number of people who get on their bikes is low.

CrowdScience listener Hans wants to know whether it’s time to change our tactics. Could we persuade more people to cycle if we moved away from focusing on well-intentioned rational arguments and use messages that appeal to our desires and vanity instead? What does the science say? Presenter Caroline Steel is on the case.

She meets Winnie Sambu from World Bicycle Relief to learn about why people in countries like Kenya to choose the bike to get around. She heads out on a ride with psychologist Professor Ian Walker from the University of Swansea to find out what barriers there might be to persuading people to cycle.

She also takes a lesson from one of the world’s top cycling nations as she talks to Marie Kåstrup, a cycling campaigns expert who has advised the Danish government on inspiring cycling and sustaining it in the city of Copenhagen. Also in Denmark, Caroline meets behavioural scientist Dr Pelle Guldborg Hansen who shares his experience in the art of persuasion.

Presenter: Caroline Steel

Was there ever a time when life on earth was peaceful? Free of violence? No predators, no prey, just... vibes? Or has nature always been 'Red in Tooth and Claw'?

Have we always been eating each other?

Our listener Scott sent us on a quest to discover the origins of predators and prey, and to find out what all this ‘eat or be eaten’ stuff is really about.

Taking us back to the very dawn of life on earth, Professor Susannah Porter from the University of Santa Barbara lets Alex peer into an extraordinary world of microscopic warfare. It’s a dog-eat-dog (or, microbe-dissolve-microbe) world, with single celled organisms doing battle with each other. For billions of years, this was life on earth! Tiny, violent, and completely fascinating.

But what about bigger creatures? More complex ones - animals? Speeding forward several billion years, Alex arrives in the Ediacaran Period – a time of unusual tranquility, where strange, plant-like animals lived in relative peace. At the Natural History Museum in Oxford, UK, palaeontologist Dr Frankie Dunn shows him around.

So where did real predators come from, then? Alex is joined by Dr Imran Rahman as he ushers in one of the most extraordinary periods in Earth’s history – the magnificently named Cambrian Explosion! Here we find real predators, with teeth, claws, and impressive hunting appendages. Through the fossil record, we can see an arms race developing – as predators get more sophisticated, so does their prey. It’s ON.

Finally, Alex wonders if our own evolution, shaped as it has been by this predator-prey arms race, might have been very different without the threat of being chomped. Professor Lynne Isbell from the University of California, Davis takes Alex on a trip into our primate past, and tackles one of our most fearsome predators: snakes.

Presenter: Alex Lathbridge

In the dead of night at his home in Machinjiri, Malawi, CrowdScience listener John can hear a small, but persistent, hum. Whenever it’s quiet enough, the hum is there – but what’s causing it? And is John the only one who can hear it?

Reports of consistent, low-pitched noise have been popping up around the world for decades. No one knows this better than Dr Glen MacPherson, who runs the World Hum Map. He tells presenter Caroline Steel his theory for what’s behind these hums.

And Caroline does some investigating of her own. We visit the Isle of Lewis off the coast of Scotland, where residents are reporting a hum. We hear about the impact that persistent noise has on people’s lives, and find out… can Caroline hear the hum too?

We also ask why some people can hear a hum but others can’t. We head to an anechoic chamber – one of the quietest places in the world – to speak to Professor Jordan Cheer, who puts Caroline’s low-frequency hearing to the test.

From industrial activity to internally generated sounds, we sift through the noise to try and find out what could be causing listener John’s hum.

Presenter: Caroline Steel

Listener Christine wants to understand one of the strangest phenomena in the universe. But to get to grips with it, she’ll need a crash course in the bizarre behaviour of the very small. Here, things don’t act the way you might expect — and it’s famously hard to wrap your head around.

Anand Jagatia has assembled some of the sharpest minds in the field and locked them in a studio. No one’s getting out until Christine and Anand know exactly what’s going on. Or at least, that’s the plan.

On hand to help are Kanta Dihal, lecturer in science communication at Imperial College London; James Millen, King’s Quantum Director at King’s College London; and particle physicist Harry Cliff from the University of Cambridge.

Prepare to enter the world of the very small—and the very weird—where particles can be in two places at once, influence each other across vast distances, and seem to decide what they are only when observed. Hear how these once-theoretical oddities are now driving a technological revolution, transforming everything from computing to communication.

Presenter: Anand Jagatia

CrowdScience listener Saoirse is vegan and doesn’t eat honey. But she’s been wondering - might honey actually have environmental benefits, by giving bee populations a boost?

To find out, presenter Anand Jagatia dons a bee suit and opens up some hives with biologist Dave Goulson, who reveals that there are over 20,000 bee species on earth – and not all of them need saving. Honeybee researcher Alison Mcafee talks about the importance of beekeeping for crop pollination, and why honeybee colonies around the world are collapsing. Although, as she explains, in some places beekeeping might actually be bad for endangered wild bees. We travel to Kenya to meet Loise Njeru and Lucy King, who show how the humble honeybee can be a powerful tool for conservation – helping to protect the mighty elephant. And, on a rooftop in London, former beekeeper Alison Benjamin explains how we can support the wild bee species that need our help.

Producer and presenter: Anand Jagatia

Bulgaria is famous for its yoghurt, a fermented milk food full of ‘good’ bacteria that has kept hungry Bulgarians healthy for over 4000 years.

Inspired by that, and a question from a CrowdScience listener in California USA, Marnie Chesterton and Caroline Steel are immersing themselves in Bulgarian culture with a programme about Bulgarian cultures, recorded at the 2025 Sofia Science Festival.

So, are the ‘live’ cultures in fermented foods actually alive by the time you eat them, and how can you tell? If you can eat the mould in blue cheese, can you eat the mould on cheese that isn’t supposed to be mouldy? Is traditional food really better for you? And if you put a drop of vanilla into a litre of milk, how come it all tastes of vanilla?

Marnie and Caroline are joined by a chemist who was a member of Sofia University’s ‘Rapid Explosion Force’, a food technologist with a PhD in sponge cakes and a Professor of molecular biology who says that we contain so much bacteria that we’re only 10% human.

With questions on food from around the world and from the audience in Sofia, Marnie and Caroline will be digesting the answers, as well as some local delicacies.

Presenter: Marnie Chesterton & Caroline Steel

You may have grown up hearing the saying “red sky at night, sailor’s delight, red sky in morning, sailor’s warning” - or maybe a variation of it. CrowdScience listener Alison, who sees many dazzling red skies from her home in the Yukon, Canada, certainly did. And now she wonders if the saying is a sensible prediction of coming weather or just another old wives’ tale.

Alison and presenter Anand Jagatia run a little experiment, getting up at the crack of dawn and staying up until dusk for 5 days to record if the sunset and sunrise can predict their local weather.

While we wait for the results, we track this weather proverb back to its ancient roots to find out how important it may have been to the people without satellites or even thermometers to guide them.

We also tap into the expertise of modern-day weather predictors, meteorologists. What are the atmospheric pressure systems that cause red skies, and how do they influence the weather globally? And what exceptions to the rules might turn a trusty old proverb on its head?

Presenter: Anand Jagatia

Some people fall asleep almost as soon as their head touches the pillow, while for others it can take hours of tossing and turning. CrowdScience listener Assia needs at least 45 minutes to get to sleep: it's always taken her a long time to drift off no matter how tired she is, and nothing seems to make a difference. She asked us to investigate. 

Presenter Caroline Steel turns to experts to find out what happens in our bodies when we fall asleep, and why it’s more difficult for some than others. Eus van Someren explains how our bodies know when it’s time to get some rest and what can influence the difficulty of getting to sleep from our earliest years. Morten Kringelbach reveals that there may be more stages of sleep than we thought, and Ada Eban-Rothschild tells us why we have something to learn from the birds and the bees about getting a good night’s rest.

Caroline has trouble getting to sleep herself, and volunteers to have her sleep monitored in Cardiff University’s sleep lab. And we share some expert tips on falling asleep more easily.

Presenter: Caroline Steel 

With thanks to Professor Milton Mermikides for permission to include his composition ‘Transitions’.

(Photo: Caroline Steel takes a nap in Cardiff University’s sleep lab)