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The Kuiper Belt

Melvyn Bragg and guests discuss the Kuiper Belt region, home to Pluto and countless remnants from the beginnings of our solar system.

Melvyn Bragg and guests discuss the Kuiper Belt, a vast region of icy objects at the fringes of our Solar System, beyond Neptune, in which we find the dwarf planet Pluto and countless objects left over from the origins of the solar system, some of which we observe as comets. It extends from where Neptune is, which is 30 times further out than the Earth is from the Sun, to about 500 times the Earth-Sun distance. It covers an immense region of space and it is the part of the Solar System that we know the least about, because it is so remote from us and has been barely detectable by Earth-based telescopes until recent decades. Its existence was predicted before it was known, and study of the Kuiper Belt, and how objects move within it, has led to a theory that there may be a 9th planet far beyond Neptune.


Carolin Crawford
Public Astronomer at the Institute of Astronomy and Fellow of Emmanuel College, University of Cambridge

Monica Grady
Professor of Planetary and Space Sciences at the Open University


Stephen Lowry
Reader in Planetary and Space Sciences, University of Kent

Producer: Simon Tillotson.

Available now

48 minutes

Last on

Thu 2 Mar 2017 21:30



Carolin Crawford at the University of Cambridge

Monica Grady at the Open University

Stephen Lowry at the University of Kent

Kuiper Belt - NASA

New Horizons mission - NASA

Kuiper Belt - Wikipedia



M. A. Barucci, H. Boehnhardt, D. P. Cruikshank, A. Morbidelli, Renee Dotson (eds.), The Solar System Beyond Neptune (University of Arizona Press, 2008)

Mike Brown, How I Killed Pluto and Why It Had It Coming (Spiegel & Grau, 2012)

Alain Doressoundiram and Emmanuel Lellouch, At the Edge of the Solar System: Icy New Worlds Unveiled (Springer Praxis Books, 2010)

Joan Kloster, Exploring the Kuiper Belt and the Trans-Neptunian Region (CreateSpace Independent Publishing Platform, 2015)

Lucy-Ann McFadden, Torrence V. Johnson, Paul R. Weissman (eds.), Encyclopedia of the Solar System (Academic Press, 2006)

Govert Schilling, The Hunt for Planet X: New Worlds and the Fate of Pluto (Copernicus, 2009)

David A. Weintraub, Is Pluto a Planet?: A Historical Journey through the Solar System (Princeton University Press, 2006)


Role Contributor
Presenter Melvyn Bragg
Interviewed Guest Carolin Crawford
Interviewed Guest Monica Grady
Interviewed Guest Stephen Lowry
Producer Simon Tillotson


  • Thu 2 Mar 2017 09:00
  • Thu 2 Mar 2017 21:30

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