André-Louis Danjon
French astronomer (1890-1967) · France · On the map · Scientists · Died at 77
André-Louis Danjon was a French astronomer who served as director of the Observatory of Strasbourg from 1930 to 1945 and of the Paris Observatory from 1945 to 1963.
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A typical day, 30 days to 11 October 2026
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About this person
He developed several astronomical instruments to examine the regularity of the rotation of the earth and among his discoveries was an acceleration of the rotation of the Earth during periods of intense solar activity occurring in 11-year cycles correlated with an increase in earthquakes. The Danjon scale is used for measuring the intensity of lunar eclipses. He noted an increase in the number of dark lunar eclipses with solar activity which is termed as the Danjon effect.
The same award as André-Louis
David ElbazBoth received Prize Jaffé
Dorothea KlumpkeBoth received Ladies' award of the Astronomical Society of France
Ioannis IliopoulosBoth received Three Physicists Prize
Jean-Claude PeckerBoth received Three Physicists Prize
Lucien RudauxBoth received Ladies' award of the Astronomical Society of France