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 1690 With Martin Rees Astronomer Royal, Fellow of Trinity College, Cambridge Carolin Crawford Emeritus Member of the Institute of Astronomy and Emeritus Fellow of Emmanuel College, University of Cambridge And Mark Sullivan Professor of Astrophysics at the University of Southampton Producer: Simon Tillotson
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 Copenhagen J...
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. With Rebecca Bell Senior lecturer in Geology and Geophysics at Imperial College London Zoe Mildon Lecturer in Earth Sciences and Future Leaders Fellow at the University of Plymouth And James Hammond Reader in Geophysics at Birkbeck, University of London Producer: Simon Tillotson
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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. With Monica Grady Professor of Planetary and Space Sciences at the Open University Carolin Crawford Institute of Astronomy, Cambridge and an Emeritus Fellow of Emmanuel College, University of Cambridge And Jim Bennett Keeper Emeritus at the Science Museum in London. Studio producer: John Goudie
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. With Steve Jones Senior Research Fellow in Genetics at University College London Nicola Foster Lecturer in Marine Biology at the University of Plymouth And Gareth Williams Associate Professor in Marine Biology at Bangor University School of Ocean Sciences Producer Simon Tilllotson.
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. With Bruce Cameron Reed The Charles A. Dana Professor of Physics Emeritus at Alma College, Michigan Cynthia Kelly Founder and President of the Atomic Heritage Foundation And Frank Close Emeritus Professor of Theoretical Physics at the University of Oxford and a Fellow of Exeter College, Oxford Producer: Simon Tillotson
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. With Anjali Goswami Research Leader in Life Sciences and Dean of Postgraduate Education at the Natural History Museum Philip Mannion Lecturer in the Department of Earth Sciences at University College London And Steve Brusatte Professor of Palaeontology and Evolution at the University of Edinburgh Producer Simon Tillotson
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. With Rebekah Higgitt Principal Curator of Science at National Museums Scotland Jim Bennett Keeper Emeritus at the Science Museum And Simon Schaffer Professor of History and Philosophy of Science at the University of Cambridge Producer: Simon Tillotson
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'. With Marcus du Sautoy Simonyi Professor for the Public Understanding of Science and Professor of Mathematics at the University of Oxford Timothy Gowers Professor of Mathematics at the College de France And Colva Roney-Dougal Professor of Pure Mathematics at the University of St Andrews Producer: Simon Tillotson