Melvyn Bragg and guests discuss the most abundant lifeform on Earth: the viruses that 'eat' bacteria. Early in the 20th century, scientists noticed that something in their Petri dishes was making bacteria disappear and they called these bacteriophages, things that eat bacteria. From studying these phages, it soon became clear that they offered countless real or potential benefits for understanding our world, from the tracking of diseases to helping unlock the secrets of DNA to treatments for long term bacterial infections. With further research, they could be an answer to the growing problem of antibiotic resistance.With Martha Clokie Director for the Centre for Phage Research and Professor of Microbiology at the University of LeicesterJames Ebdon Professor of Environmental Microbiology at the University of BrightonAnd Claas Kirchhelle Historian and Chargé de Recherche at the French National Institute of Health and Medical Research’s CERMES3 Unit in Paris.Producer: Simon TillotsonIn Our Time is a BBC Studios Audio ProductionReading list: James Ebdon, ‘Tackling sources of contamination in water: The age of phage’ (Microbiologist, Society for Applied Microbiology, Vol 20.1, 2022) Thomas Häusler, Viruses vs. Superbugs: A Solution to the Antibiotics Crisis? (Palgrave Macmillan, 2006)Tom Ireland, The Good Virus: The Untold Story of Phages: The Mysterious Microbes that Rule Our World, Shape Our Health and Can Save Our Future (Hodder Press, 2024)Claas Kirchhelle and Charlotte Kirchhelle, ‘Northern Normal–Laboratory Networks, Microbial Culture Collections, and Taxonomies of Power (1939-2000)’ (SocArXiv Papers, 2024) Dmitriy Myelnikov, ‘An alternative cure: the adoption and survival of bacteriophage therapy in the USSR, 1922–1955’ (Journal of the History of Medicine and Allied Sciences 73, no. 4, 2018)Forest Rohwer, Merry Youle, Heather Maughan and Nao Hisakawa, Life in our Phage World: A Centennial Field Guide to Earth’s most Diverse Inhabitants (Wholon, 2014)Steffanie Strathdee and Thomas Patterson (2019) The Perfect Predator: A Scientist’s Race to Save Her Husband from a Deadly Superbug: A Memoir (Hachette Books, 2020)William C. Summers, Félix d`Herelle and the Origins of Molecular Biology (Yale University Press, 1999)William C. Summers, The American Phage Group: Founders of Molecular Biology (University Press, 2023)

Melvyn Bragg and guests discuss the planet which is closest to our Sun. We see it as an evening or a morning star, close to where the Sun has just set or is about to rise, and observations of Mercury helped Copernicus understand that Earth and the other planets orbit the Sun, so displacing Earth from the centre of our system. In the 20th century, further observations of Mercury helped Einstein prove his general theory of relativity. For the last 50 years we have been sending missions there to reveal something of Mercury's secrets and how those relate to the wider universe, and he latest, BepiColombo, is out there in space now. WithEmma Bunce Professor of Planetary Plasma Physics and Director of the Institute for Space at the University of LeicesterDavid Rothery Professor of Planetary Geosciences at the Open UniversityAnd Carolin Crawford Emeritus Fellow of Emmanuel College, University of Cambridge, and Emeritus Member of the Institute of Astronomy, CambridgeProducer: Simon Tillotson In Our Time is a BBC Studios Audio productionReading list: Emma Bunce, ‘All (X-ray) eyes on Mercury’ (Astronomy & Geophysics, Volume 64, Issue 4, August 2023) Emma Bunce et al, ‘The BepiColombo Mercury Imaging X-Ray Spectrometer: Science Goals, Instrument Performance and Operations’ (Space Science Reviews: SpringerLink, volume 216, article number 126, Nov 2020)David A. Rothery, Planet Mercury: From Pale Pink Dot to Dynamic World (Springer, 2014)

Melvyn Bragg and guests discuss the Serbian-American inventor Nikola Tesla (1856-1943) and his role in the development of electrical systems towards the end of the nineteenth century. He made his name in New York in the contest over which current should flow into homes and factories in America. Some such as Edison backed direct current or DC while others such as Westinghouse backed alternating current or AC and Nikola Tesla’s invention of a motor that worked on AC swung it for the alternating system that went on to power the modern age. He ensured his reputation and ideas burnt brightly for the next decades, making him synonymous with the lone, genius inventor of the new science fiction. With Simon Schaffer Emeritus Fellow of Darwin College, University of CambridgeJill Jonnes Historian and author of “Empires of Light: Edison, Tesla, Westinghouse and the Race to Electrify the World”And Iwan Morus Professor of History at Aberystwyth UniversityProducer: Simon TillotsonReading list: W. Bernard Carlson, Tesla: Inventor of the Electrical Age (Princeton University Press, 2013)Margaret Cheney and Robert Uth, Tesla: Master of Lightning (Barnes & Noble Books, 1999) Thomas P. Hughes, Networks of Power: Electrification in Western Society, 1880-1930 (Johns Hopkins University Press, 1983)Carolyn Marvin, When Old Technologies Were New (Open University Press, 1988)Iwan Rhys Morus, Nikola Tesla and the Electrical Future (Icon Books, 2019)Iwan Rhys Morus, How The Victorians Took Us To The Moon (Icon, 2022)David E. Nye, Electrifying America: Social Meanings of a New Technology (MIT Press, 1991)John J. O’Neill, Prodigal Genius: The Life of Nikola Tesla (first published 1944; Cosimo Classics, 2006)Marc J. Seifer, Wizard: The Life and Times of Nikola Tesla, Biography of a Genius (first published 1996; Citadel Press, 2016)Nikola Tesla, My Inventions: The Autobiography of Nikola Tesla (first published 1919; Martino Fine Books, 2011)Nikola Tesla, My Inventions and other Writings (Penguin, 2012)In Our Time is a BBC Studios Audio production

Melvyn Bragg and guests discuss the German physicist who, at the age of 23 and while still a student, effectively created quantum mechanics for which he later won the Nobel Prize. Werner Heisenberg made this breakthrough in a paper in 1925 when, rather than starting with an idea of where atomic particles were at any one time, he worked backwards from what he observed of atoms and their particles and the light they emitted, doing away with the idea of their continuous orbit of the nucleus and replacing this with equations. This was momentous and from this flowed what’s known as his Uncertainty Principle, the idea that, for example, you can accurately measure the position of an atomic particle or its momentum, but not both.With Fay Dowker Professor of Theoretical Physics at Imperial College LondonHarry Cliff Research Fellow in Particle Physics at the University of CambridgeAnd Frank Close Professor Emeritus of Theoretical Physics and Fellow Emeritus at Exeter College at the University of OxfordProducer: Simon TillotsonReading list:Philip Ball, Beyond Weird: Why Everything You Thought You Knew about Quantum Physics Is Different (Vintage, 2018)John Bell, ‘Against 'measurement'’ (Physics World, Vol 3, No 8, 1990)Mara Beller, Quantum Dialogue: The Making of a Revolution (University of Chicago Press, 2001)David C. Cassidy, Beyond Uncertainty: Heisenberg, Quantum Physics, And The Bomb (Bellevue Literary Press, 2010) Werner Heisenberg, Physics and Philosophy (first published 1958; Penguin Classics, 2000)Carlo Rovelli, Helgoland: The Strange and Beautiful Story of Quantum Physics (Penguin, 2022)

Melvyn Bragg and guests discuss some of the chemical signals coursing through our bodies throughout our lives, produced in separate areas and spreading via the bloodstream. We call these 'hormones' and we produce more than 80 of them of which the best known are arguably oestrogen, testosterone, adrenalin, insulin and cortisol. On the whole hormones operate without us being immediately conscious of them as their goal is homeostasis, maintaining the levels of everything in the body as required without us having to think about them first. Their actions are vital for our health and wellbeing and influence many different aspects of the way our bodies work.WithSadaf Farooqi Professor of Metabolism and Medicine at the University of CambridgeRebecca Reynolds Professor of Metabolic Medicine at the University of EdinburghAndAndrew Bicknell Associate Professor in the School of Biological Sciences at the University of ReadingProduced by Victoria BrignellReading list:Rachel Carson, Silent Spring (first published 1962; Penguin Classics, 2000)Stephen Nussey and Saffron Whitehead, Endocrinology: An Integrated Approach (BIOS Scientific Publishers; 2001)Aylinr Y. Yilmaz, Comprehensive Introduction to Endocrinology for Novices (Independently published, 2023)

This podcast explores the fascinating world of plankton, discussing their role in oxygen production, carbon cycling, and the marine food web. It also delves into the potential impact of iron on plankton growth and the importance of plankton in informing decision-making for managing the marine environment. The podcast highlights the significance of international collaboration, funding for research, and the role of the podcast producer, Simon Tilottson.

Explore the life and work of Albert Einstein, from his papers that revolutionized physics to his theory of special relativity. Learn about Einstein's early education, struggles, and decision to pursue theoretical physics. Discover his opposition to German militarism and his emergence as a public intellectual. Dive into Einstein's general theory of relativity and his intellectual and moral courage.

Jupiter is the largest planet in our solar system, and it’s hard to imagine a world more alien and different from Earth. It’s known as a Gas Giant, and its diameter is eleven times the size of Earth’s: our planet would fit inside it one thousand three hundred times. But its mass is only three hundred and twenty times greater, suggesting that although Jupiter is much bigger than Earth, the stuff it’s made of is much, much lighter. When you look at it through a powerful telescope you see a mass of colourful bands and stripes: these are the tops of ferocious weather systems that tear around the planet, including the great Red Spot, probably the longest-lasting storm in the solar system. Jupiter is so enormous that it’s thought to have played an essential role in the distribution of matter as the solar system formed – and it plays an important role in hoovering up astral debris that might otherwise rain down on Earth. It’s almost a mini solar system in its own right, with 95 moons orbiting around it. At least two of these are places life might possibly be found. WithMichele Dougherty, Professor of Space Physics and Head of the Department of Physics at Imperial College London, and principle investigator of the magnetometer instrument on the JUICE spacecraft (JUICE is the Jupiter Icy Moons Explorer, a mission launched by the European Space Agency in April 2023)Leigh Fletcher, Professor of Planetary Science at the University of Leicester, and interdisciplinary scientist for JUICECarolin Crawford, Emeritus Fellow of Emmanuel College, University of Cambridge, and Emeritus Member of the Institute of Astronomy, Cambridge

Melvyn Bragg and guests discuss the power-packs within cells in all complex life on Earth. Inside each cell of every complex organism there are structures known as mitochondria. The 19th century scientists who first observed them thought they were bacteria which had somehow invaded the cells they were studying. We now understand that mitochondria take components from the food we eat and convert them into energy. Mitochondria are essential for complex life, but as the components that run our metabolisms they can also be responsible for a range of diseases – and they probably play a role in how we age. The DNA in mitochondria is only passed down the maternal line. This means it can be used to trace population movements deep into human history, even back to an ancestor we all share: mitochondrial Eve. With Mike Murphy Professor of Mitochondrial Redox Biology at the University of CambridgeFlorencia Camus NERC Independent Research Fellow at University College Londonand Nick Lane Professor of Evolutionary Biochemistry at University College LondonProducer Luke Mulhall

Melvyn Bragg and guests discuss the life, ideas and legacy of the pioneering Swedish botanist Carl Linnaeus (1707 – 1778). The philosopher Jean-Jacques Rousseau once wrote: "Tell him I know no greater man on earth". The son of a parson, Linnaeus grew up in an impoverished part of Sweden but managed to gain a place at university. He went on to transform biology by making two major innovations. He devised a simpler method of naming species and he developed a new system for classifying plants and animals, a system that became known as the Linnaean hierarchy. He was also one of the first people to grow a banana in Europe. WithStaffan Muller-Wille University Lecturer in History of Life, Human and Earth Sciences at the University of CambridgeStella Sandford Professor of Modern European Philosophy at Kingston University, Londonand Steve Jones Senior Research Fellow in Genetics at University College, LondonProducer Luke Mulhall