CrowdScience

BBC World Service
  • 4.7 (426)
  • SCIENCE
  • UPDATED BIWEEKLY

We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.

  1. 1D AGO

    How long will traces of our civilisation last?

    What will remain of us hundreds of millions of years from now? And how can we be so certain that we are the first technologically advanced species on Earth? These unsettling questions have been haunting listener Steve. If fossils can be lost to deep time through erosion and subduction into the Earth’s mantle, how would anyone — or anything — ever know that we had been here? And if an earlier species had built a civilization that rose and fell, would we even be able to find traces of it? To investigate, CrowdScience presenter Caroline Steel speaks to the scientists trying to answer these questions, while producer Sam Baker goes fossil hunting on the Jurassic Coast in the UK. Caroline speaks with astrophysicist Adam Frank at the University of Rochester in the US, who along with NASA scientist Gavin Schmidt developed the Silurian hypothesis – the idea that if an advanced species had existed deep in Earth’s past, they might have vanished without leaving a trace. But palaeontologists Jan Zalasiewicz and Sarah Gabbott from the University of Leicester in the UK argue that humans are already leaving an indelible mark in the form the chemical and material fingerprints we’re pressing into Earth’s crust. They contend that the ‘technofossils’ we are producing will last a very long time indeed. Along the way, Caroline and producer Sam discover just how rare fossils really are, how even the tiniest particles of pollution will give us away to far-future explorers, and why car parks might be our ultimate legacy. What they find is at once unsettling and oddly comforting: humanity could be fleeting, but our impact probably won’t be. Could we really have missed evidence of an ancient civilization? And what strange clues will we leave behind for whoever, or whatever, comes next? We explore Earth’s geological memory to find out. Presenter: Caroline Steel Producer: Sam Baker Editor: Ben Motley (Photo: Old phone embedded in concrete layer with defocused landscape background Credit: Petra Richli Via Getty Images)

    34 min

  2. AUG 22

    How does camouflage work?

    Camouflage isn't just for chameleons! Military forces around the world deck their soldiers out in those distinctive green and brown uniforms, to give them the best chance of staying safe, and remaining undetected. But how do they work? Why do they look so different from country to country? And why do you still see soldiers wearing it in the city, when it can't possibly work as camouflage? These are the questions in the mind of Crowdscience listener Paul, in Uganda. In his home of Kampala he often sees soldiers on patrol. As a botanist, he's fascinated by the nature-inspired designs, and he wants to know how they came to be. So Alex Lathbridge sets off to find out. At Camolab at the University of Bristol, Laszlo Talas talks Alex through the history of battle-dress. There have been some extraordinary designs over the years, some of them quite beautiful in their way, and many with hidden easter eggs printed into the design! In a patch of forest on the outskirts of Prague, Alex gets to try some of the latest gear out for himself. Fully kitted out in ghillie suit, camouflage chaps, face mask and goggles, he tries to disappear into tue background. With the help of 4M Tactical, the company who manufacture a cloak currently in use in Ukraine. It has the power to make you invisible, not just in the visible spectrum, but in the infrared too. With high tech sensors and infrared cameras now a staple of the modern battlefield, clothes like this are becoming essential. Not all camouflage technology belongs to the military. Futuristic clothing company Vollebak in London are using 'the fabrics of the future' to design high tech streetwear for savvy 21st century urban warriors. Founder Steve Tindall shows Alex their prototype Thermal Camo Jacket, which uses hundreds of layers of graphene to give the illusion of heat, or cold. Steve says that hiding in plain sight is less about concealing yourself from human eyes, and more about avoiding the pervasive sensors and constant surveillance that are increasingly a feature of urban living. Meanwhile in Sweden, they're taking the inspiration from chameleons more literally. Hans Karis, deputy research director of the Swedish defence institute FOI, introduces Alex to their Adaptive Camouflage, interwoven with a network of tiny coloured LEDs to change colour at will. It's not on the market yet, but perhaps chameleon soldiers will be a thing of the future. Presented by Alex Lathbridge Produced by Emily Knight (Photo: Thermal imaging of people in the woods)

    37 min

  3. AUG 15

    How long does light last?

    When listener Rob from Devon, UK, heard of a newly detected planet light years away, he was struck by the sheer scale the light must travel to reach us here on Earth. It got him wondering: How long does light last? What is the oldest light we have ever observed? And does light ever die? To find out, presenter Anand Jagatia calls on some of the brightest minds in astronomy and physics. Astronomer Matthew Middleton from the University of Southampton explains how scientists still struggle to define exactly what light is. What we do know is that light comes in many forms, and choosing the right kind can peel back the cosmic curtain, revealing the universe’s deepest and darkest secrets. That knowledge will prove vital in Anand’s search for the oldest light ever observed. At the European Southern Observatory in Chile, staff astronomer Pascale Hibon gives Anand a behind-the-scenes look at the Very Large Telescope, one of the most advanced optical instruments on Earth, perfectly placed under some of the clearest skies on the planet. Light from the objects Pascale studies has often travelled for billions of years, making her images snapshots of the distant past. If light has crossed the vastness of the universe to reach us, it must be unimaginably ancient. But what will become of it in the far future? Could we trap it and preserve it forever? Miles Padgett at the University of Glasgow, has spent his career trying to pin it down. As Anand discovers, physics can be more philosophical than you might expect. Presenter: Anand Jagatia Producer: Harrison Lewis Editor: Ilan Goodman (Photo: An area of deep space with thousands of galaxies in various shapes and sizes on a black background. Most are circles or ovals, with a few spirals. Credit:G. Östlin, P. G. Perez-Gonzalez, J. Melinder, the Jades collaboration, M. Zamani/ESA/Webb, Nasa and CSA)

    26 min

  4. AUG 8

    Can we stop the rain?

    CrowdScience listener Rit, from Pune in India, is staring out of his window at the falling rain. It’s been pouring for four days now, and shows no sign of stopping. The laundry is piling up, all his shoes are wet, and he’s worried about the effect it’s having on the environment, and on agriculture. When it rains like this, the animals suffer, and the crops are destroyed. Cloud seeding and Weather Engineering are hot topics right now, and can bring the rain to places that need it. But Rit wants to know whether we can artificially stop the pouring rain, especially in an emergency. Following the devastating floods in Texas, it’s clearly not just a problem for countries with a monsoon season. Presenter Chhavi Sachdev is also sitting in a downpour at home in Mumbai. She dons her rain jacket and rubber boots to try and find out whether science can help Rit with his question. From controlling the clouds in India, to bringing rain to the deserts of the UAE, to firing high-powered lasers into the skies above Geneva, we find out what weather engineering is really capable of. With thanks to: Dr Thara Prabhakaran, from the Indian Institute of Tropical Meteorology Alya Al Mazroui, Director of the UAE Research Program for Rain Enhancement Science Jean-Pierre Wolf, Applied Physics Department of the University of Geneva Presenter: Chhavi Sachdev Producer: Emily Knight Series Producer: Ben Motley (Image: Girl carrying umbrella while standing on road against trees during rainfall. Credit: Cavan Images/Getty Images)

    32 min

  5. AUG 1

    How are teeth made?

    CrowdScience listener Jon started wondering how our teeth are created while he was in the dentist’s chair. It took his mind off the drilling. He wants to know how our teeth are made, what goes into them and how come we only get two sets of teeth when other animals, like sharks, grow thousands of new ones throughout their lives. Anand Jagatia goes back to prehistoric times to discover how the story of teeth began millions of years ago. Palaeontologist Yara Haridy explains that teeth weren’t designed originally for eating at all, but as a kind of armour on the exoskeletons of fish that was also sensitive to the environment. It turns out that our teeth in fact are part of our evolutionary success story. Biological anthropologist Peter Ungar reveals that we flourished as a species because our teeth are designed to get the maximum energy from our food. Anand discovers how teeth can even be grown in a lab when he meets researchers Ana Angelova Volponi and Xuechen Zhang whose team has managed to replicate the environment in which teeth develop. He also talks to Katsu Takahashi who has discovered a method for developing a third set of teeth. It’s a whole new way of creating teeth that will change the way we make them. Presenter Anand Jagatia Producer Jo Glanville Editor Ben Motley Studio Manager Bob Nettles Production co-ordinator Ishmael Soriano Translation, Katsu Takahashi interview Bethan Jones

    30 min
  6. Trailer: 13 Minutes Presents: The Space Shuttle

    JUL 28

    Trailer: 13 Minutes Presents: The Space Shuttle

    The epic space story of a sci-fi dream that changed spaceflight forever. Told by the Nasa astronauts and team who made it happen. Our multi-award-winning podcast is back, hosted by space scientist Maggie Aderin-Pocock. She tells the story of triumph and tragedy - of a dream that revolutionised modern space travel forever. You can listen to the trailer here. To hear episodes, search for 13 Minutes Presents: The Space Shuttle, wherever you get your BBC podcasts. 13 Minutes Presents: The Space Shuttle is a BBC Audio Science Unit production for the BBC World Service. Theme music by Hans Zimmer and Christian Lundberg, and produced by Russell Emanuel, for Bleeding Fingers Music. Archive: Mission audio and oral histories, Nasa History Office.

    3 min

  7. JUL 25

    Could technology improve our brains?

    What comes to mind when you imagine the future of humanity? Could a computer make your mind more efficient? Enhance your cognition? Or cure a disorder you've been grappling with all your life? CrowdScience listener Mariana from Mexico hopes that one day technology will be able to help improve our brains.  Presenter Alex Lathbridge seeks out some of these brain boosters, exploring emerging technologies in deep brain stimulation at City St George’s University of London in the UK. Professor Francesca Morgante and Dr Lucia Ricciard explain how they’re using technology to treat Parkinson’s. And could brain technology help with even the most enigmatic elements of our minds? Dr Robert Hampson at Wake Forest University in the USA takes us through his research in restoring memory impairment.   Along the way we interrogate the ethical implications of the breakneck speed of progress in brain augmentation research with researcher Anders Sandberg from the Institute of Future Studies in Sweden.    Presenter: Alex Lathbridge  Producer: Emily Bird  Series Producer: Ben Motley

    26 min

  8. JUL 18

    What if the Earth spun backwards?

    Your whole life is governed by spin. The rotation of our planet tells you when to wake up, and Earth’s orbit around the Sun is the reason why some of us dig out a jumper for half the year and a t-shirt for the rest. But what if that all changed? That’s exactly what 8-year-old Geronimo in Ecuador wants to know. He and his dad, Fabian, have got themselves dizzy trying to figure out what would happen if the Earth stopped spinning, or better yet, started spinning in the opposite direction. Would everyone fly off into space? Would school be at night? Eager for answers, they decided to ask CrowdScience. Presenter Anand Jagatia embarks on an interstellar journey, blasting off with the celestial origins of spin itself. Astronomer Amy Bonsor from the University of Cambridge in the UK explains how Earth’s rotation began, with collapsing clouds of gas, planetary pile-ups and crushing gravitational force. At Keele Observatory, things get apocalyptic. Anand meets astronomer Jacco van Loon, who explains what would happen if Geronimo somehow waved a magic wand and brought Earth’s rotation to a halt. With months of unbroken daylight or darkness, devastating storms and even the loss of the Earth’s magnetic shield, it’s like the script of a disaster movie. Wave that magic wand again and we imagine a world where the Earth not only stops... but starts spinning the other way. Meteorologist Joao Basso from the University of Leipzig in Germany walks us through a mind-bending 2018 study that tells us the surprising things that would happen to the global climate. Presenter: Anand Jagatia Producer: Harrison Lewis Series Producer: Ben Motley

    26 min
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Hosts & Guests

4.7
out of 5
426 Ratings

About

We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.

Information

  • Creator
    BBC World Service
  • Years Active
    2016 - 2025
  • Episodes
    456
  • Rating
    Clean
  • Copyright
    © (C) BBC 2025
  • Show Website
    CrowdScience

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