The Earth’s Core

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.

→ Listen on BBC Sounds website

Guests

• Stephen Blundell 3 episodes
  Professor of Physics and Fellow of Mansfield College at the University of Oxford
• Arwen Deuss No other episodes
  Associate Professor in Seismology at Utrecht University
• Simon Redfern No other episodes
  Professor of Mineral Physics at the University of Cambridge

Reading list

• Magnetism: A Very Short Introduction
  Stephen J. Blundell (Oxford University Press, 2012) Google Books →
• Nebulous Earth: A History of Modern Planetary Physics
  Stephen G. Brush (Cambridge University Press, 1996) Google Books →
• Fundamentals of Geophysics
  William Lowrie (Cambridge University Press, 2007) Google Books →
• Our Magnetic Earth: The Science of Geomagnetism
  Ronald T. Merrill (University of Chicago Press, 2010) Google Books →
• The Earth: A Very Short Introduction
  Martin Redfern (Oxford University Press, 2003) Google Books →
• Physics of the Earth
  Frank D. Stacey and Paul M. Davis (Cambridge University Press, 2008) Google Books →

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Programme ID: b05s3gyv

Episode page: bbc.co.uk/programmes/b05s3gyv

Auto-category: 550 (Earth sciences)

Hello (First sentence from this episode)

Hello, it's said that we know more about the composition of the Sun, 90 million miles away, than we do about the core of our own planet Earth.