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Solar Wind

Melvyn Bragg and guests discuss the phenomenon behind the auroras at Earth's poles, the stream of charged particles spreading out from the Sun to the border of the solar system.

Melvyn Bragg and guests discuss the flow of particles from the outer region of the Sun which we observe in the Northern and Southern Lights, interacting with Earth's magnetosphere, and in comet tails that stream away from the Sun regardless of their own direction. One way of defining the boundary of the solar system is where the pressure from the solar wind is balanced by that from the region between the stars, the interstellar medium. Its existence was suggested from the C19th and Eugene Parker developed the theory of it in the 1950s and it has been examined and tested by a series of probes in C20th up to today, with more planned.


Andrew Coates
Professor of Physics and Deputy Director in charge of the Solar System at the Mullard Space Science Laboratory, University College London

Helen Mason OBE
Reader in Solar Physics at the Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Fellow at St Edmund's College


Tim Horbury
Professor of Physics at Imperial College London

Producer: Simon Tillotson

Available now

55 minutes

Last on

Thu 23 Jan 2020 21:30


Andrew Coates at University College London

Helen Mason at the University of Cambridge

Tim Horbury at Imperial College London

Solar Orbiter – European Space Agency

Parker Solar Probe - NASA

Solar wind - National Oceanic and Atmospheric Administration

Space weather - Met Office

‘A step closer to the Sun’s secrets’ by Daniel Verscharen - Nature, December 2019

UK Space Agency

Science and Technology Facilities Council

Solar wind - Wikipedia



Wolfgang Baumjohann and Rudolf A. Treumann, Basic Space Plasma Physics (Imperial College Press, 1996)

Pal Brekke, Our Explosive Sun: A Visual Feast of Our Source of Light and Life (Springer, 2012)

Stuart Clark, The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began (Princeton University Press, 2009)

Thomas E. Cravens, Physics of Solar System Plasmas (Cambridge University Press, 1997)

Leon Golub and Jay M. Pasachoff, The Sun (Reaktion Books, 2017)

Lucie Green, 15 Million Degrees: A Journey to the Centre of the Sun (Penguin, 2016)

Margaret G. Kivelson and Christopher T. Russell, Introduction to Space Physics (Cambridge University Press, 1995)

Kenneth R. Lang, Sun, Earth and Sky (Springer, 1995)

Nicole Meyer-Vernet, Basics of the Solar Wind (Cambridge University Press, 2007)

Kenneth J. H. Phillips, Guide to the Sun (Cambridge University Press, 1992)

C. T. Russell, J. G. Luhmann and R. J. Strangeway, Space Physics: An Introduction (Cambridge University Press, 2016)



  • Thu 23 Jan 2020 09:00
  • Thu 23 Jan 2020 21:30

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