17 Jan, 2013 520 Astronomy

Melvyn Bragg and his guests discuss comets, the ‘dirty snowballs’ of the Solar System. In the early 18th century the Astronomer Royal Sir Edmond Halley compiled a list of appearances of comets, bright objects like stars with long tails which are occasionally visible in the night sky. He concluded that many of these apparitions were in fact the same comet, which returns to our skies around every 75 years, and whose reappearance he correctly predicted. Halley’s Comet is today the best known example of a comet, a body of ice and dust which orbits the Sun. Since they contain materials from the time when the Solar System was formed, comets are regarded by scientists as frozen time capsules, with the potential to reveal important information about the early history of our planet and others.

Play on BBC Sounds website


  • Monica Grady 9 episodes
    Professor of Planetary and Space Sciences at the Open University
  • Paul Murdin 5 episodes
    Senior Fellow at the Institute of Astronomy at the University of Cambridge
  • Don Pollacco 2 episodes
    Professor of Astronomy at the University of Warwick

Reading list

  • Introduction to Comets
    John Brandt and Robert Chapman (Cambridge University Press, 2004) Google Books →
  • Comets: Creators and Destroyers
    David H. Levy (Simon & Schuster, 1998) Google Books →
  • Fire and Ice: A History of Comets in Art
    Roberta Olson (Walker & Co, 1985) Google Books →
  • Comets, Popular Culture, and the Birth of Modern Cosmology
    Sara Schechner (Princeton University Press, 1999) Google Books →
  • The Great Comet Crash: The Collision of Comet Shoemaker-Levy 9 and Jupiter
    John R. Spencer and Jacqueline Mitton (eds.) (Cambridge University Press, 1995) Google Books →
  • Comets and the Origin and Evolution of Life
    Paul J. Thomas, Roland D. Hicks, Christopher F. Chyba, Christopher P. McKay (eds.) (Springer, 2006) Google Books →

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Auto-category: 520 (Astronomy & allied sciences)

Hello (First sentence from this episode) Hello. One evening in April 837, a strange new star was spotted in the skies above Northern Europe.