Melvyn Bragg and guests discuss the tiny drifting organisms in the oceans that sustain the food chain for all the lifeforms in the water and so for the billions of people who, in turn, depend on the seas for their diet.  In Earth's development, the plant-like ones among them, the phytoplankton, produced so much oxygen through photosynthesis that around half the oxygen we breathe today originated there. And each day as the sun rises, the animal ones, the zooplankton, sink to the depths of the seas to avoid predators in such density that they appear on ship sonars like a new seabed, only to rise again at night in the largest migration of life on this planet.WithCarol Robinson
Professor of Marine Sciences at the University of East AngliaAbigail McQuatters-Gollop
Associate Professor of Marine Conservation at the University of PlymouthAndChristopher Lowe
Lecturer in Marine Biology at Swansea UniversityProducer: Simon TillotsonReading list: Juli Berwald, Spineless: The Science of Jellyfish and the Art of Growing a Backbone (Riverhead Books, 2018)Sir Alister Hardy, The Open Sea: The World of Plankton (first published 1959; Collins New Naturalist Library, 2009) Richard Kirby, Ocean Drifters: A Secret World Beneath the Waves (Studio Cactus Ltd, 2010)Robert Kunzig, Mapping the Deep: The Extraordinary Story of Ocean Science (Sort Of Books, 2000)Christian Sardet, Plankton: Wonders of the Drifting World (University of Chicago Press, 2015) Helen Scales, The Brilliant Abyss: True Tales of Exploring the Deep Sea, Discovering Hidden Life and Selling the Seabed (Bloomsbury Sigma, 2022)

Plankton

Melvyn Bragg and guests discuss the man who, in 1905, produced several papers that were to change the world of physics and whose name went on to become a byword for genius. This was Albert Einstein, then still a technical expert at a Swiss patent office, and that year of 1905 became known as his annus mirabilis (&#39;miraculous year&#39;).  While Einstein came from outside the academic world, some such as Max Planck championed his theory of special relativity, his principle of mass-energy equivalence that followed, and his explanations of Brownian Motion and the photoelectric effect.  Yet it was not until 1919, when a solar eclipse proved his theory that gravity would bend light, that Einstein became an international celebrity and developed into an almost mythical figure.With Richard Staley
Professor in History and Philosophy of Science at the University of Cambridge and Professor in History of Science at the University of CopenhagenDiana Kormos Buchwald
Robert M. Abbey Professor of History and Director and General Editor of The Einstein Papers Project at the California Institute of TechnologyAndJohn Heilbron 
Professor Emeritus at the University of California, BerkeleyProducer: Simon TillotsonReading list: Ronald W. Clark, Einstein: The Life and Times (first published 1971; HarperPaperbacks, 2011)Albert Einstein (eds. Jurgen Renn and Hanoch Gutfreund), Relativity: The Special and the General Theory - 100th Anniversary Edition (Princeton University Press, 2019)Albert Einstein, Out of My Later Years (first published 1950; Citadel Press, 1974)Albert Einstein (ed. Paul A. Schilpp), Albert Einstein: Philosopher-Scientist: The Library of Living Philosophers Volume VII (first published 1949; Open Court, 1970)Albert Einstein (eds. Otto Nathan and Heinz Norden), Einstein on Peace (first published 1981; Literary Licensing, 2011)Albrecht Folsing, Albert Einstein: A Biography (Viking, 1997)J. L. Heilbron, Niels Bohr: A Very Short Introduction (Oxford University Press, 2020)Walter Isaacson, Einstein: His Life and Universe (Simon &amp; Schuster, 2008)Max Jammer, Einstein and Religion (Princeton University Press, 2002)Michel Janssen and Christoph Lehner (eds.), The Cambridge Companion to Einstein (Cambridge University Press, 2014)Dennis Overbye, Einstein in Love: A Scientific Romance (Viking, 2000)Abraham Pais, Subtle Is the Lord: The Science and the Life of Albert Einstein (Oxford University Press, 1982)David E. Rowe and Robert Schulmann (eds.), Einstein on Politics: His Private Thoughts and Public Stands on Nationalism, Zionism, War, Peace, and the Bomb (Princeton University Press, 2007)Matthew Stanley, Einstein&#39;s War: How Relativity Triumphed Amid the Vicious Nationalism of World War I (Dutton, 2019)Fritz Stern, Einstein’s German World (Princeton University Press, 1999)A. Douglas Stone, Einstein and the Quantum: The Quest of the Valiant Swabian (Princeton University Press, 2013)Milena Wazeck (trans. Geoffrey S. Koby), Einstein&#39;s Opponents: The

Albert Einstein

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

Mitochondria

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

Linnaeus

Paul Erdős (1913 – 1996) is one of the most celebrated mathematicians of the 20th century. During his long career, he made a number of impressive advances in our understanding of maths and developed whole new fields in the subject. He was born into a Jewish family in Hungary just before the outbreak of World War I, and his life was shaped by the rise of fascism in Europe, anti-Semitism and the Cold War. His reputation for mathematical problem solving is unrivalled and he was extraordinarily prolific.  He produced more than 1,500 papers and collaborated with around 500 other academics.  He also had an unconventional lifestyle. Instead of having a long-term post at one university, he spent much of his life travelling around visiting other mathematicians, often staying for just a few days. With Colva Roney-Dougal 
Professor of Pure Mathematics at the University of St AndrewsTimothy Gowers
Professor of Mathematics at the College de France in Paris and Fellow of Trinity College, CambridgeandAndrew Treglown
Associate Professor in Mathematics at the University of BirminghamThe image above shows a graph occurring in Ramsey Theory. It was created by Dr Katherine Staden, lecturer in the School of Mathematics at the Open University.

Paul Erdős

Melvyn Bragg and guests discuss the pioneering Danish astronomer Tycho Brahe (1546 – 1601) whose charts offered an unprecedented level of accuracy.In 1572 Brahe's observations of a new star challenged the idea, inherited from Aristotle, that the heavens were unchanging. He went on to create his own observatory complex on the Danish island of Hven, and there, working before the invention of the telescope, he developed innovative instruments and gathered a team of assistants, taking a highly systematic approach to observation. A second, smaller source of renown was his metal prosthetic nose, which he needed after a serious injury sustained in a duel. The image above shows Brahe aged 40, from the Atlas Major by Johann Blaeu. With Ole Grell
Emeritus Professor in Early Modern History at the Open University Adam Mosley 
Associate Professor of History at Swansea University and Emma Perkins
Affiliate Scholar in the Department of History and Philosophy of Science at the University of Cambridge.

Tycho Brahe

Melvyn Bragg and guests discuss the discovery made in 1911 by the Dutch physicist Heike Kamerlingh Onnes (1853-1926).  He came to call it Superconductivity and it is a set of physical properties that nobody predicted and that none, since, have fully explained.  When he lowered the temperature of mercury close to absolute zero and ran an electrical current through it, Kamerlingh Onnes found not that it had low resistance but that it had no resistance.  Later, in addition, it was noticed that a superconductor expels its magnetic field.  In the century or more that has followed, superconductors have already been used to make MRI scanners and to speed particles through the Large Hadron Collider and they may perhaps bring nuclear fusion a little closer (a step that could be world changing).The image above is from a photograph taken by Stephen Blundell of a piece of superconductor levitating above a magnet.With Nigel Hussey
Professor of Experimental Condensed Matter Physics at the University of Bristol and Radbout UniversitySuchitra Sebastian
Professor of Physics at the Cavendish Laboratory at the University of CambridgeAndStephen Blundell
Professor of Physics at the University of Oxford and Fellow of Mansfield CollegeProducer: Simon Tillotson

Superconductivity

Melvyn Bragg and guests discuss the voyage of HMS Challenger which set out from Portsmouth in 1872 with a mission a to explore the ocean depths around the world and search for new life. The scale of the enterprise was breath taking and, for its ambition, it has since been compared to the Apollo missions.  The team onboard found thousands of new species, proved there was life on the deepest seabeds and plumbed the Mariana Trench five miles below the surface.  Thanks to telegraphy and mailboats, its vast discoveries were shared around the world even while Challenger was at sea, and they are still being studied today, offering insights into the ever-changing oceans that cover so much of the globe and into the health of our planet.The image above is from the journal of Pelham Aldrich R.N. who served on the Challenger Surveying Expedition from 1872-5.WithErika Jones
Curator of Navigation and Oceanography at Royal Museums GreenwichSam Robinson
Southampton Marine and Maritime Institute Research Fellow at the University of SouthamptonAndGiles Miller
Principal Curator of Micropalaeontology at the Natural History Museum LondonProducer: Simon Tillotson

The Challenger Expedition 1872-1876

Melvyn Bragg and guests discuss one of the greatest changes in the history of life on Earth. Around 400 million years ago some of our ancestors, the fish, started to become a little more like humans. At the swampy margins between land and water, some fish were turning their fins into limbs, their swim bladders into lungs and developed necks and eventually they became tetrapods, the group to which we and all animals with backbones and limbs belong. After millions of years of this transition, these tetrapod descendants of fish were now ready to leave the water for a new life of walking on land, and with that came an explosion in the diversity of life on Earth.The image above is a representation of Tiktaalik Roseae, a fish with some features of a tetrapod but not one yet, based on a fossil collected in the Canadian Arctic.WithEmily Rayfield
Professor of Palaeobiology at the University of BristolMichael Coates
Chair and Professor of Organismal Biology and Anatomy at the University of ChicagoAnd Steve Brusatte
Professor of Palaeontology and Evolution at the University of EdinburghProducer: Simon Tillotson

The Fish-Tetrapod Transition

Melvyn Bragg and guests discuss an atomic particle that's become inseparable from modernity. JJ Thomson discovered the electron 125 years ago, so revealing that atoms, supposedly the smallest things, were made of even smaller things. He pictured them inside an atomic ball like a plum pudding, with others later identifying their place outside the nucleus - and it is their location on the outer limit that has helped scientists learn so much about electrons and with electrons.  We can use electrons to reveal the secrets of other particles and, while electricity exists whether we understand electrons or not, the applications of electricity and electrons grow as our knowledge grows. Many questions, though, remain unanswered.With Victoria Martin
Professor of Collider Physics at the University of EdinburghHarry Cliff
Research Fellow in Particle Physics at the University of CambridgeAndFrank Close
Professor Emeritus of Theoretical Physics and Fellow Emeritus at Exeter College at the University of OxfordProducer: Simon Tillotson

The Electron

Melvyn Bragg and guests discuss the abrupt transformation of stars after shining brightly for millions or billions of years, once they lack the fuel to counter the force of gravity. Those like our own star, the Sun, become red giants, expanding outwards and consuming nearby planets, only to collapse into dense white dwarves. The massive stars, up to fifty times the mass of the Sun, burst into supernovas, visible from Earth in daytime, and become incredibly dense neutron stars or black holes. In these moments of collapse, the intense heat and pressure can create all the known elements to form gases and dust which may eventually combine to form new stars, new planets and, as on Earth, new life.The image above  is of the supernova remnant Cassiopeia A, approximately 10,000 light years away, from a once massive star that died in a supernova explosion that was first seen from Earth in 1690WithMartin Rees
Astronomer Royal, Fellow of Trinity College, CambridgeCarolin Crawford
Emeritus Member of the Institute of Astronomy and Emeritus Fellow of Emmanuel College, University of CambridgeAndMark Sullivan
Professor of Astrophysics at the University of SouthamptonProducer: Simon Tillotson

The Death of Stars

Melvyn Bragg and guests discuss one of our ancestors, Homo erectus, who thrived on Earth for around two million years whereas we, Homo sapiens, emerged only in the last three hundred thousand years.  Homo erectus, or Upright Man, spread from Africa to Asia and it was on the Island of Java that fossilised remains were found in 1891 in an expedition led by Dutch scientist Eugène Dubois. Homo erectus people adapted to different habitats, ate varied food, lived in groups, had stamina to outrun their prey; and discoveries have prompted many theories on the relationship between their diet and the size of their brains, on their ability as seafarers, on their creativity and on their ability to speak and otherwise communicate.The image above is from a diorama at the Moesgaard Museum in Denmark, depicting the Turkana Boy referred to in the programme. With Peter Kjærgaard
Director of the Natural History Museum of Denmark and Professor of Evolutionary History at the University of CopenhagenJosé Joordens
Senior Researcher in Human Evolution at Naturalis Biodiversity Centre and Professor of Human Evolution at Maastricht UniversityAndMark Maslin
Professor of Earth System Science at University College LondonProducer: Simon Tillotson

Homo erectus

Melvyn Bragg and guests discuss the study of earthquakes. A massive earthquake in 1755 devastated Lisbon, and this disaster helped inspire a new science of seismology which intensified after San Francisco in 1906 and advanced even further with the need to monitor nuclear tests around the world from 1945 onwards.  While we now know so much more about what lies beneath the surface of the Earth, and how rocks move and crack, it remains impossible to predict when earthquakes will happen. Thanks to seismology, though, we have a clearer idea of where earthquakes will happen and how to make some of them less hazardous to lives and homes.WithRebecca Bell
Senior lecturer in Geology and Geophysics at Imperial College LondonZoe Mildon
Lecturer in Earth Sciences and Future Leaders Fellow at the University of PlymouthAnd James Hammond
Reader in Geophysics at Birkbeck, University of LondonProducer: Simon Tillotson

Seismology

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Melvyn Bragg and guests discuss William Herschel (1738 – 1822) and his sister Caroline Herschel (1750 – 1848) who were born in Hanover and made their reputation in Britain. William was one of the most eminent astronomers in British history. Although he started life as a musician, as a young man he became interested in studying the night sky. With an extraordinary talent, he constructed telescopes that were able to see further and more clearly than any others at the time. He is most celebrated today for discovering the planet Uranus and detecting what came to be known as infrared radiation. Caroline also became a distinguished astronomer, discovering several comets and collaborating with her brother.WithMonica Grady
Professor of Planetary and Space Sciences at the Open UniversityCarolin Crawford
Institute of Astronomy, Cambridge and an Emeritus Fellow of Emmanuel College, University of CambridgeAndJim Bennett
Keeper Emeritus at the Science Museum in London.Studio producer: John Goudie

William and Caroline Herschel

Melvyn Bragg and guests discuss the simple animals which informed Charles Darwin's first book, The Structure and Distribution of Coral Reefs, published in 1842.  From corals, Darwin concluded that the Earth changed very slowly and was not fashioned by God. Now coral reefs, which some liken to undersea rainforests, are threatened by human activity, including fishing, pollution and climate change. WithSteve Jones 
Senior Research Fellow in Genetics at University College LondonNicola Foster 
Lecturer in Marine Biology at the University of Plymouth AndGareth Williams 
Associate Professor in Marine Biology at Bangor University School of Ocean SciencesProducer  Simon Tilllotson.

Corals

Melvyn Bragg and guests discuss the race to build an atom bomb in the USA during World War Two.  Before the war, scientists in Germany  had discovered the potential of nuclear fission and scientists in Britain soon argued that this could be used to make an atom bomb, against which there could be no defence other than to own one. The fear among the Allies was that, with its head start, Germany might develop the bomb first and, unmatched, use it on its enemies.  The USA took up the challenge in a huge engineering project led by General Groves and Robert Oppenheimer and, once the first bomb had been exploded at Los Alamos in July 1945, it appeared inevitable that the next ones would be used against Japan with devastating results.The image above is of Robert Oppenheimer and General Groves examining the remains of one the bases of the steel test tower, at the atomic bomb Trinity Test site, in September 1945.WithBruce Cameron Reed
The Charles A. Dana Professor of Physics Emeritus at Alma College, MichiganCynthia Kelly
Founder and President of the Atomic Heritage FoundationAndFrank Close
Emeritus Professor of Theoretical Physics at the University of Oxford and a Fellow of Exeter College, OxfordProducer: Simon Tillotson

The Manhattan Project

Melvyn Bragg and guests discuss the remarkable diversity of the animals that dominated life on land in the Triassic, before the rise of the dinosaurs in the Jurassic, and whose descendants are often described wrongly as 'living fossils'. For tens of millions of years, the ancestors of alligators and Nile crocodiles included some as large as a bus, some running on two legs like a T Rex and some that lived like whales. They survived and rebounded from a series of extinction events but, while the range of habitats of the dinosaur descendants such as birds covers much of the globe, those of the crocodiles have contracted, even if the animals themselves continue to evolve today as quickly as they ever have.WithAnjali Goswami
Research Leader in Life Sciences and Dean of Postgraduate Education at the Natural History MuseumPhilip Mannion
Lecturer in the Department of Earth Sciences at University College London AndSteve Brusatte
Professor of Palaeontology and Evolution at the University of EdinburghProducer Simon Tillotson

The Evolution of Crocodiles

Melvyn Bragg and guests discuss the search for Longitude while at sea.  Following efforts by other maritime nations, the British Government passed the Longitude Act in 1714 to reward anyone who devised reliable means for ships to determine their longitude at sea.  Mariners could already calculate how far they were north or south, the Latitude, using the Pole Star, but voyaging across the Atlantic to the Caribbean was much less predictable as navigators could not be sure how far east or west they were, a particular problem when heading for islands.  It took fifty years of individual genius and collaboration in Britain and across Europe, among astronomers, clock makers, mathematicians and sailors, for the problem to be resolved.WithRebekah Higgitt
Principal Curator of Science at National Museums ScotlandJim Bennett
Keeper Emeritus at the Science MuseumAnd Simon Schaffer
Professor of History and Philosophy of Science at the University of CambridgeProducer: Simon Tillotson

Longitude

Melvyn Bragg and guests discuss Laplace (1749-1827) who was a giant in the world of mathematics both before and after the French Revolution. He addressed one of the great questions of his age, raised but side-stepped by Newton: was the Solar System stable, or would the planets crash into the Sun, as it appeared Jupiter might, or even spin away like Saturn threatened to do?  He advanced ideas on probability, long the preserve of card players, and expanded them out across science; he hypothesised why the planets rotate in the same direction; and he asked if the Universe was deterministic, so that if you knew everything about all the particles then you could predict the future. He also devised the metric system and reputedly came up with the name 'metre'.
  
WithMarcus du Sautoy
Simonyi Professor for the Public Understanding of Science and Professor of Mathematics at the University of OxfordTimothy Gowers
Professor of Mathematics at the College de FranceAndColva Roney-Dougal
Professor of Pure Mathematics at the University of St AndrewsProducer: Simon Tillotson

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