CrowdScience

Stare up at the night sky, and if you’re lucky, you might see a shooting star. Some people might make a wish, but CrowdScience listener Scott in California in the USA, thinks differently. He’s wondering how dangerous they might be.
Shooting stars are actually meteors, ending their incredible journey whizzing through the depths of space by burning through our atmosphere, and crashing down to earth. And Scott’s not wrong to worry about them! In May 2026, an enormous meteor exploded off the coast of Massachusetts, causing a loud sonic boom before crashing into the ocean, releasing the equivalent energy of 300 tons of TNT!
So, how many meteors make it to our atmosphere in the first place? How many of them survive long enough to make it to the surface? How many come down in places where people live, and how much should we be worried about it happening to us?
Marnie Chesterton is peering up into the sky for answers.
PRESENTER: Marnie Chesterton
PRODUCER: Emily Knight
EDITOR: Ben Motley
(photo: Meteor Impact On Earth - Fired Asteroid In Collision With Planet - Contain 3d Rendering - elements of this image furnished by NASA - stock photo- Credit: RomoloTavani via Getty Images)

We’re delving into the CrowdScience archive to give you another chance to hear an award-winning show from 2025.
CrowdScience listener Dorit has a problem. She wants the tiles in her new bathroom to be arranged randomly but, no matter what she does, it still looks like they form some kind of pattern.
This has got Dorit thinking about randomness – what is it, how do you create it, why do we find it so hard to recognise, and is anything really random at all? And if nothing is truly random, does it mean that everything is theoretically predictable? Tiling your bathroom is a much more existential problem than you might have thought.
Never afraid of a question, whether big (is everything pre-determined?) or small (how do I tile my bathroom?), CrowdScience is on the case.
Anand Jagatia heads to Switzerland to meet Hugo Duminil-Copin, a mathematician at the University of Geneva who specialises in probability theory. On the top floor of an old bank, Hugo has Anand flipping an imaginary coin in a random order. Hugo explains that randomness is something that cannot be predicted by any means – so why is it so easy for Hugo to guess what Anand’s next move is?
Meanwhile, at the National Institutes of Mental Health in Maryland USA, Susan Wardle is a cognitive neuroscientist who researches how the human brain processes visual information. Can neuroscience help Dorit with her tiling problem, and is there a reason why the human brain likes to put random objects into some kind of order?
Geneva is also the birthplace of the first Quantum Random Number Generator for smartphones, and CrowdScience has persuaded some of the University of Geneva’s finest quantum physicists to hook a photon detector up to a synthesiser. Thanks to Tiff Brydges and Nicolas Brunner, we can actually hear quantum particles behaving randomly. But is quantum randomness truly random, or just a pattern that we can’t see? And could quantum physics help Dorit tile her bathroom?
Presenter: Anand Jagatia
Producer: Ben Motley
Editor: Cathy Edwards
(Photo: Many wooden dice - stock photo- Credit: akiyoko via Getty Images)

Space missions are searching for evidence of extra-terrestrial life. CrowdScience listener George in Kenya wants to know what could be up there, and if there’s a risk it could harm humanity.
With rovers currently analysing samples on Mars, missions searching for the building blocks of life on Jupiter’s icy moons, George’s concern that there could be diseases in space is timely. Presenter Anand Jagatia sets out to try and find an answer while keeping his feet on the Earth.
He meets astrobiologist Dr Michaela Musilova, who runs experiments to try and understand what kinds of microbes could survive on other planets. In her work at NASA’s Jet Propulsion Laboratory, she recreates Mars-like environments that test lifeforms’ resilience to the rigours of the Red Planet.
And if there are harmful pathogens in space, how do we make sure these missions don't bring them back to Earth? Anand talks to ‘planetary protection officer’ Silvio Sinibaldi from the European Space Agency, who explains what experts are doing to protect us. He helps Anand get suited and booted in specialist clothing so they can enter a highly sterile environment called a ‘clean room’, where things being sent to space are built.
He also meets Paul Meacham, former chief engineer on the Rosalind Franklin Rover. The rover is being sent to Mars to try to determine whether life ever existed there, and even whether it still does.
Paul shows us around the Airbus Defence and Space site where his team built the rover and explains high-tech measures to avoid contamination.
And what would a programme on space be without an astronaut? Anand meets Kate Rubins, who spent 300 days on the International Space Station. While she was there, she ran experiments investigating what happens to microbes in space. It turns out that microbes affect humans differently in orbit to how they affect us on Earth.
Presenter: Anand Jagatia
Producer: Tom Bonnett
Editor: Ben Motley
(Photo : 3D render of the Coronavirus Covid-19 floating in the air with astronaut wearing space suit. - stock photo- Credit: Artur Debat via Getty Images)

CrowdScience listener Liana from Canada got in touch to ask about some very specific rocks she’d seen on an island in Indonesia – jagged, rugged and a very strange shape: hexagonal. They were in long columns, and clicked together like a jigsaw. But what are they, and how did they get there?
Across the world in the UK, CrowdScience listener Sarah emailed us to ask about the famous rocks of the Giant’s Causeway in Northern Ireland. What makes them so uniformly hexagonal?
Presenter Alex Lathbridge investigates, visiting the Giant’s Causeway to speak to geologist Dr Kirstin Lemon from the Geological Survey of Northern Ireland. She explains how this amazing landscape formed, and why the mythical rocks look the way they do today.
We also hear from Dr Alfend Rudyawan from Institut Teknologi Bandung in Indonesia about Liana’s intriguing rocks. Are these distant locations more closely related than you might think?
And we look to nature – because angular, uniform hexagons crop up surprisingly often. Professor Jean-Marc Schlenker from the University of Luxembourg explains why hexagons are much better than other shapes.
Presenter: Alex Lathbridge
Producer: Hannah Fisher
Editor: Ben Motley
(photo: Giant`s Causeway in Northern Ireland Stock photo- Credit: MANUEL FIL ORDIERES GARCIA via Getty Images)

Many plants need pollen from another plant of the same species in order to reproduce, but they don’t have legs so they can’t simply walk around looking for a mate.
As a result, many of them rely on animals to transfer pollen from one plant to another. They’ve developed a hugely diverse range of techniques to attract them, including their appearance, taste and smell. CrowdScience listener Alice in the UK wants to know how they have evolved to do this.
To try and answer the question, presenter Anand Jagatia goes trekking up a mountain in the Philippines, battling mud and leeches in the hunt for an incredibly rare flower. Rafflesia has evolved to look and smell like rotting meat in order to attract flies, so it’s the perfect example of a plant that goes to fascinating extremes to make sure it gets pollinated.
It only blooms for a few days each year, so to find it Anand is going to need the help of scientists at the University of the Philippines Los Baños and Lewis Barrett, Senior Botanical Propagator at the University of Oxford Botanic Garden and Arboretum.
Anand also visits the University of the Philippines Laguna Quezon Land Grant, a huge site containing more than 5,500 hectares of protected forest land. Professor Pastor Malabrigo Jr shows him a fig tree that has a fascinatingly gruesome relationship with its pollinator wasps.
So how did these amazingly diverse plants end up needing insect pollinators in the first place? Dr Kyra Krakos is a professor of biology at Maryville University and a research associate at the Missouri Botanical Garden in the United States. She explains to Anand that plants are surprisingly sexy – but how did they end up needing insects to survive?
Back in the Philippines, Anand’s guides have never actually seen the Rafflesia flower themselves, despite many attempts. So could this be the time they finally get lucky?
Presenter: Anand Jagatia
Producer: Dan Welsh
Editor: Ben Motley
With special thanks to Dr Chris Thorogood, Associate Professor of Biology at the University of Oxford and founder of the Community for the Conservation & Research of Rafflesia
(photo: Edited high angle view of Rafflesia on green gradient - Stock photo- Credit: Mohamed Tazi Cherti / 500px via Getty Images)