Daniel Chalonge (January 21, 1895 – November 28, 1977) was a French

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

and astrophysicist. He was born in

Grenoble lat, Gratianopolis , commune status = Prefecture and commune , image = Panorama grenoble.png , image size = , caption = From upper left: Panorama of the city, Grenoble’s cable cars, place Saint- ...

and studied in Paris under

Charles Fabry Maurice Paul Auguste Charles Fabry (; 11 June 1867 – 11 December 1945) was a French physicist. Life Fabry graduated from the École Polytechnique in Paris and received his doctorate from the University of Paris in 1892, for his work on i ...

. Chalonge worked as an astronomer at the Observatoire de Paris, the Observatoire d'Haute Provence and the Swiss Jungfraujoch Scientific Station. One of the founders of the

Institut d'astrophysique de Paris The Institut d'Astrophysique de Paris (translated: Paris Institute of Astrophysics) is a research institute in Paris, France. The Institute is part of the Sorbonne University and is associated with the CNRS Centre national de la recherche scientifiq ...

, his studies included the stellar

spectrum A spectrum (plural ''spectra'' or ''spectrums'') is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors i ...

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...

, stellar

photometry Photometry can refer to: * Photometry (optics), the science of measurement of visible light in terms of its perceived brightness to human vision * Photometry (astronomy), the measurement of the flux or intensity of an astronomical object's electro ...

and classification, and measurement of the

ozone layer The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in rela ...

. During the Nazi occupation of France, Chalogne assumed the position of director of the Institut d'astrophysique de Paris after the previous director, Henri Mineur, was arrested by the

Gestapo The (), abbreviated Gestapo (; ), was the official secret police of Nazi Germany and in German-occupied Europe. The force was created by Hermann Göring in 1933 by combining the various political police agencies of Prussia into one organi ...

. Chalonge developed a microphotometer, which was subsequently named after him. Between 1936 and 1982 he authored (or co-authored) over 90 scientific papers. Chalonge died in

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

, survived by his wife and two daughters, Karen and Sonia.

Awards and honors

* Janssen Medal from the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...

(1949) * The crater Chalonge on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

is named after him. * Chalonge mountain in the

Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...

is named after him. * The ''International School of Astrophysics Daniel Chalonge'' is named after him. * The ''Daniel Chalonge Museum'' in

Erice Erice (; scn, Èrici) is a historic town and ''comune'' in the province of Trapani, Sicily, in southern Italy. Geography The main town of Erice is located on top of Mount Erice, at around above sea level, overlooking the city of Trapani, the ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

is named after him.

References

External links

International School of Astrophysics Daniel Chalonge
1895 births 1975 deaths 20th-century French astronomers {{france-astronomer-stub