The Bruce Medalists


  Portrait Photo courtesy Observatoire de Paris
Bernard Ferdinand Lyot
27 February 1897 1947 Bruce Medalist 2 April 1952

After studying engineering at l’École Supérieure d'Électricité in Paris, Bernard Lyot assisted the physicist Alfred Pérot at l'École Polytechnique. During this period he also studied mathematics, physics, and chemistry at the University of Paris. From 1920 to 1952 he worked at the Meudon Observatory, which became part of the Paris Observatory in 1926. There he was encouraged by its director, Henri Deslandres. An expert in optics and an ingenious inventor, Lyot constructed a polariscope of unprecedented sensitivity to investigate the polarization of light reflected from the planets. Making many observations at the Pic du Midi Observatory, he found that the lunar surface behaves like volcanic dust and that Mars has sandstorms, and he investigated the atmospheres of the other planets. Starting in 1929 he improved his polarimeter and developed an optical system that eliminated scattered light to create the coronagraph, a device which allows observation of the solar corona without an eclipse. By 1931 he was obtaining photographs of the corona and its spectrum. He developed monochromatic polarizing filters with transmission only one angstrom wide for his solar studies. He found new spectral lines in the corona, and he made the first motion pictures of solar prominences in 1935 [a better version compiled later]. Lyot died while returning from an eclipse expedition to Sudan.

Presentation of Bruce medal
Wilson, Ralph E., PASP 59, 53-58 (1947).

Other awards
French Academy of Sciences, Lalande Medal, 1928.
Société Astronomique de France, Janssen Prize, 1932.
Franklin Institute, Potts medal, 1942.
National Academy of Sciences, Henry Draper Medal, 1951
Royal Astronomical Society, Gold medal, 1939, presented by H.C. Plummer, MNRAS 99, 538-40 (1939).

Biographical materials
D’Azambuja, L., “l’Oeuvre de Bernard Lyot,” l’Astronomie 66, 265-277 (1952).
Bitterman, Jay, Lake County Astronomical Society
Charbonneau, Paul, Great Moments in the History of Solar Physics
Club Astronomique du Val de Loir [in French]
Baum, Richard, Biographical Encyclopedia of Astronomers (Springer, NY, 2007), pp. 718-19.
de Broglie, Louis, Notice sur la vie et l’oeuvre de Bernard Lyot; lecture faite en la seance annuelle des prix du 8 decembre 1969 (Palais de l’Institut, Paris, 1969).
Dollfus, A., “Bernard Lyot, l’Invention du Coronographe et l’Étude de la Couronne: Un Cinquantenaire,” l’Astronomie 97, 107-28 & 315-29 (1983).
Gros, Monique, “Bernard Lyot (1897-1952),” l’Astronomie 112, 8-12 (1998).
Le Coultre, M. F, Bernard Lyot et l’Astrophysique. Brochure, 1955.
Lévy, Jacques, Dictionary of Scientific Biography 8, 581-82.
l’Observatoire de Montréal, Bernard Lyot (1897-1952)
l’Observatoire de Paris Bibliotheque [in French].
Observatoire Midi-Pyrenees, Biographie de Bernard Lyot [in French].

Chevalier, A., Comptes Rendus 234, 1501-05 (1952).
Danjon, A., Ann. d’Astrophys. 15, 75-78 (1952).
Menzel, Donald H., Sky & Telescope 11, 193 (1952).
P[laskett], H.H., Observatory 72, 157-59 (1952).
Wilkins, H. Percy, Observatory 72, 241-42 (1952).
More obituaries

Département d’Astronomie Solaire de l’Observatoire de Paris Laboratoire de Physique du Soleil et de l’Héliosphère (several)
Pic du Midi (at the eyepiece of the Baillaud telescope in 1937)

Named after him
Minor Planet #2452 Lyot
Bernard Lyot Telescope, Pic du Midi
The Lyot Project, American Museum of Natural History

More references

The Bruce Medalists

Please send comments, additions, corrections, and questions to