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The Earth's Core

Melvyn Bragg and guests discuss the Earth's solid inner core and liquid outer core, their structures and their impact on life on Earth.

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.


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

Arwen Deuss
Associate Professor in Seismology at Utrecht University


Simon Redfern
Professor of Mineral Physics at the University of Cambridge

Producer: Simon Tillotson.

Available now

47 minutes

Last on

Thu 30 Apr 2015 21:30


Stephen Blundell at the University of Oxford

Arwen Deuss at Utrecht University

Simon Redfern at the University of Cambridge

US Geological Survey

Inner core - Wikipedia

Outer core - Wikipedia



Stephen J. Blundell, Magnetism: A Very Short Introduction (Oxford University Press, 2012)

Stephen G. Brush, Nebulous Earth: A History of Modern Planetary Physics (Cambridge University Press, 1996)

William Lowrie, Fundamentals of Geophysics (Cambridge University Press, 2007)

Ronald T. Merrill, Our Magnetic Earth: The Science of Geomagnetism (University of Chicago Press, 2010)

Martin Redfern, The Earth: A Very Short Introduction (Oxford University Press, 2003)

Frank D. Stacey and Paul M. Davis, Physics of the Earth (Cambridge University Press, 2008)



Role Contributor
Presenter Melvyn Bragg
Interviewed Guest Stephen Blundell
Interviewed Guest Arwen Deuss
Interviewed Guest Simon Redfern
Producer Simon Tillotson


  • Thu 30 Apr 2015 09:00
  • Thu 30 Apr 2015 21:30

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