The Earth's Core

The Earth's Core

Author: BBC Radio 4 April 30, 2015 Duration: 46:41

Melvyn Bragg and his guests discuss the Earth's Core. The inner core is an extremely dense, solid ball of iron and nickel, the size of the Moon, while the outer core is a flowing liquid, the size of Mars. Thanks to the magnetic fields produced within the core, life on Earth is possible. The magnetosphere protects the Earth from much of the Sun's radiation and the flow of particles which would otherwise strip away the atmosphere. The precise structure of the core and its properties have been fascinating scientists from the Renaissance. Recent seismographs show the picture is even more complex than we might have imagined, with suggestions that the core is spinning at a different speed and on a different axis from the surface.

With

Stephen Blundell Professor of Physics and Fellow of Mansfield College at the University of Oxford

Arwen Deuss Associate Professor in Seismology at Utrecht University

and

Simon Redfern Professor of Mineral Physics at the University of Cambridge

Producer: Simon Tillotson.


Melvyn Bragg and a panel of academic experts gather each week to explore the vast history of scientific thought on In Our Time: Science. This BBC Radio 4 podcast delves far beyond simple explanations, instead tracing the long and often winding paths of discovery that shaped our understanding of the world. Each episode focuses on a single idea, from the concept of zero to the theory of plate tectonics, unpacking its origins, the controversies it sparked, and the key figures who championed or challenged it. You’ll hear lively, in-depth conversations that place science firmly within its human and historical context, revealing how principles we take for granted today were hard-won through centuries of debate, accident, and insight. The discussions are rigorous and accessible, designed for the curious mind eager to appreciate not just what we know, but how we came to know it. By treating science as a deeply historical endeavour, this series offers a richer appreciation of the discipline itself. Tune in for a thoughtful and engaging journey through the experiments, the arguments, and the brilliant flashes of imagination that have defined our quest for knowledge.
Author: Language: English Episodes: 100

In Our Time: Science
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