Space Science Reviews

, Volume 210, Issue 1–4, pp 5–35 | Cite as

History of Solar Magnetic Fields Since George Ellery Hale

  • J. O. Stenflo


As my own work on the Sun’s magnetic field started exactly 50 years ago at Crimea in the USSR, I have been a participant in the field during nearly half the time span since Hale’s discovery in 1908 of magnetic fields in sunspots. The present historical account is accompanied by photos from my personal slide collection, which show a number of the leading personalities who advanced the field in different areas: measurement techniques, from photographic to photoelectric and imaging methods in spectro-polarimetry; theoretical foundations of MHD and the origin of cosmic magnetic fields (birth of dynamo theory); the quest for increased angular resolution from national projects to international consortia (for instruments both on ground and in space); introduction of the Hanle effect in astrophysics and the Second Solar Spectrum as its playground; small-scale nature of the field, the fundamental resolution limit, and transcending it by resolution-independent diagnostics.


Sun: atmosphere Magnetic fields Polarization Dynamo Magnetohydrodynamics (MHD) 


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© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.Institute of AstronomyETH ZurichZurichSwitzerland
  2. 2.Istituto Ricerche Solari LocarnoLocarno-MontiSwitzerland

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