Uploads from Dr. Jorge S. Diaz

Currently Playing: The solar Zeeman effect

Buy me a coffee and support the channel: https://ko-fi.com/jkzero Story of the discovery of magnetic fields in sunspots, and how Hale's 1908 observations confirmed that the Zeeman effect operates at solar scale. [Related videos] ∘ Faraday's last experiment: the origin of the Zeeman effect https://youtu.be/dM5xWIsNbR4 [References] [1] P. Zeeman, "Over de invloed eener magnetisatie op den aard van het door een stof uitgezonden licht - II," Versl. Kon. Ak. Wet. 5, 242 (1896) [2] W. Herschel, "XIII. Observations tending to investigate the nature of the sun, in order to find the causes or symptoms of its variable emission of light and heat; with remarks on the use that may possibly be drawn from solar observations," Phil. Trans. R. Soc. 91:265 (1801) [3] W. Herschel, "III. On the nature and construction of the sun and fixed stars," Phil. Trans. R. Soc. 85:46 (1795) [4] J. N. Lockyer, "III. Spectroscopic observations of the sun," Proc. R. Soc. 15: 256 (1867) [5] C. A. Young, "The Sun," D. Appleton (1881) [6] A. Cortie, "Bands observed in the spectra of sun-spots at Stonyhurst Observatory," MNRAS 47, 19 (1886) [7] Ch. Fievez, Bull. de I’Academie de Belgique 9, 381 (1885) [8] P. Zeeman, "On the influence of magnetism on the nature of the light emitted by a substance," Phil. Mag. 43, 226 (1897) [9] P. Zeeman, "On the influence of magnetism on the nature of the light emitted by a substance," Ap. J. 5, 332 (1897) [10] W. M. Mitchell, "Results of Solar Observations at Princeton, 1905-1906," Ap. J. 24, 78 (1906) [11] W. M. Mitchell, "Researches in the Sun-Spot Spectrum, Region F to α," Ap. J. 22, 4 (1905) [12] G. E. Hale, "Solar Vortices," PASP 20, 203 (1908) [13] G. E. Hale, "Solar Vortices and the Zeeman Effect," PASP 20, 220 (1908) [14] P. Zeeman, "Solar magnetic fields and spectrum analysis," Nature 78, 369 (1908) [15] G. E. Hale, "On the Probable Existence of a Magnetic Field in Sun-Spots," Ap. J. 28, 315 (1908) [16] G. E. Hale, "The Magnetic Polarity of Sun-Spots ," Ap. J. 49, 153 (1919) [17] H. W. Babcock, "Remarks on Stellar Magnetism," PASP 59, 112 (1947) [18] J. C. Kemp et al. "Discovery of Circularly Polarized Light from a White Dwarf ," Ap. J. 161, L77 (1970) [19] J. Trümper et al. "Evidence for strong cyclotron line emission in the hard X-ray spectrum of Hercules X-1," Ap. J. 219, L105 (1978) [Credits] Series_of_sunspots_across_the_sun, public domain Sunspot 1302, Sep. 2011 by NASA/SDO/HMI, public domain "Project Hail Mary," Directed by Phil Lord and Christopher Miller, performances by Ryan Gosling and Sandra Hüller, Amazon MGM Studios, 2026 Sir William Herschel by J. Russell, public domain Herschel's Milky Way, public domain Fraunhofer's original spectrum, by J. Fraunhofer under CC BY-SA 4.0 Norman Lockyer, public domain Visible spectrum of helium by J. Homann under CC BY-SA 3.0 Buckingham telescope, public domain Le grand télescope Foucault, de l'Observatoire de Marseille, public domain Charles Augustus Young, public domain Fr. Aloysius Cortie SJ, British Jesuit Archives Stonyhurst Observatory, Stonyhurst College by Imaginativename under CC BY-SA 3.0 Peter Guthrie Tait, public domain Yerkes dome construction, public domain The Yerkes Observatory, public domain "The X-Files," by Chris Carter, Fox Broadcasting Company, 1993–2018 Spectroheliograph diagram by G. E. Hale, public domain Rumford spectroheliograph attached to the Yerkes telescope, public domain Lithograph of the sun, showing a sunspot; from the Wellcome Trust under CC BY 4.0 A. W. Duff, public domain Magnetic field made visible using iron filings by B. Meyer under CC BY-SA 3.0 Nicol prism by Fleaglass Sunspots and their magnetic polarity by G. E. Hale, public domain Bose–Einstein condensate by JILA, public domain EZIE mission by NASA/JHU-APL, public domain AIP: American Institute of Physics, Emilio Segrè Visual Archives CC BY-SA 3.0: https://creativecommons.org/licenses/by-sa/3.0/deed.en CC BY 4.0: https://creativecommons.org/licenses/by/4.0/deed.en CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/deed.en