Benjamin Baillaud

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Edouard Benjamin Baillaud. Benjamin baillaud.jpg
Édouard Benjamin Baillaud.

Édouard Benjamin Baillaud (14 February 1848 8 July 1934) (aged 86) was a French astronomer.

Astronomer scientist who studies celestial bodies

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, moons, comets, and galaxies – in either observational or theoretical astronomy. Examples of topics or fields astronomers study include planetary science, solar astronomy, the origin or evolution of stars, or the formation of galaxies. Related but distinct subjects like physical cosmology, which studies the Universe as a whole.



Born in Chalon-sur-Saône, Baillaud studied at the École Normale Supérieure (1866-1869) [1] and the University of Paris. He worked as an assistant at the Paris Observatory beginning in 1872. Later he was director of the Toulouse Observatory from 1878 to 1907, during much of this time serving as Dean of the University of Toulouse Faculty of Science.

Chalon-sur-Saône Subprefecture and commune in Bourgogne-Franche-Comté, France

Chalon-sur-Saône is a commune in the Saône-et-Loire department in the region of Bourgogne-Franche-Comté in eastern France.

University of Paris former university in Paris, France

The University of Paris, metonymically known as the Sorbonne, was a university in Paris, France, active 1150–1793, and 1806–1970.

Paris Observatory foremost astronomical observatory of France

The Paris Observatory, a research institution of PSL Research University, is the foremost astronomical observatory of France, and one of the largest astronomical centres in the world. Its historic building is to be found on the Left Bank of the Seine in central Paris, but most of the staff work on a satellite campus in Meudon, a suburb southwest of Paris.

He greatly expanded the observatory and enthusiastically supported the Carte du Ciel project. He specialized in celestial mechanics, in particular the motions of the satellites of Saturn.

Carte du Ciel

The Carte du Ciel and the Astrographic Catalogue were two distinct but connected components of a massive international astronomical project, initiated in the late 19th century, to catalogue and map the positions of millions of stars as faint as 11th or 12th magnitude. Twenty observatories from around the world participated in exposing and measuring more than 22,000 (glass) photographic plates in an enormous observing programme extending over several decades. Despite, or because of, its vast scale, the project was only ever partially successful – the Carte du Ciel component was never completed, and for almost half a century the Astrographic Catalogue part was largely ignored. However, the appearance of the Hipparcos Catalogue in 1997 has led to an important development in the use of this historical plate material.

Celestial mechanics is the branch of astronomy that deals with the motions of objects in outer space. Historically, celestial mechanics applies principles of physics to astronomical objects, such as stars and planets, to produce ephemeris data.

Natural satellite astronomical body that orbits a planet

A natural satellite or moon is, in the most common usage, an astronomical body that orbits a planet or minor planet.

In 1903, the observatory took over a facility on the Pic du Midi in the Pyrenees that had been founded by amateurs in the 1850s with the goal of putting a telescope there. However, the height of 2865 metres (9400 feet) posed formidable logistical challenges and the ambition had remained unrealised though a meteorological observatory had operated from 1873 to 1880. Baillaud organised a team of soldiers to erect a 0.5 metre (20 inch) reflecting telescope, and 0.25 metre refracting telescope on the summit.

Pic du Midi de Bigorre mountain

The Pic du Midi de Bigorre or simply the Pic du Midi is a mountain in the French Pyrenees famous for its Pic du Midi Observatory.

Pyrenees Range of mountains in southwest Europe

The Pyrenees is a range of mountains in southwest Europe that forms a natural border between Spain and France. Reaching a height of 3,404 metres (11,168 ft) altitude at the peak of Aneto, the range separates the Iberian Peninsula from the rest of continental Europe, and extends for about 491 km (305 mi) from the Bay of Biscay to the Mediterranean Sea.

Telescope Optical instrument that makes distant objects appear magnified

Telescopes are optical instruments that make distant objects appear magnified by using an arrangement of lenses or curved mirrors and lenses, or various devices used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. The first known practical telescopes were refracting telescopes invented in the Netherlands at the beginning of the 17th century, by using glass lenses. They found use in both terrestrial applications and astronomy.

In 1907, he became director of the Paris Observatory where he immediately set to work to relaunch the stalled Carte du Ciel project with a conference held at the observatory, entertained by singers from the Paris Opera and refreshed by wine provided by the director of the Bordeaux Observatory. Though the French government agreed to fund the project, it was becoming increasingly clear that its objectives were hopelessly unrealistic.

Wine alcoholic drink made from grapes

Wine is an alcoholic drink made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol, carbon dioxide, and heat. Different varieties of grapes and strains of yeasts produce different styles of wine. These variations result from the complex interactions between the biochemical development of the grape, the reactions involved in fermentation, the terroir, and the production process. Many countries enact legal appellations intended to define styles and qualities of wine. These typically restrict the geographical origin and permitted varieties of grapes, as well as other aspects of wine production. Wines not made from grapes include rice wine and fruit wines such as plum, cherry, pomegranate, currant and elderberry.

Bordeaux Observatory

The Bordeaux Observatory is an astronomical observatory affiliated with the University of Bordeaux. Built in Floirac, France in 1893 its lenses were focused between +11 and +17 degrees declination. Until 1970 it had taken over 4,000 photographic plates.

Baillaud was the President of the Société astronomique de France (SAF), the French astronomical society, from 1909-1911. [2]

The Société astronomique de France (SAF), the French astronomical society, is a non-profit association in the public interest organized under French law. Founded by astronomer Camille Flammarion in 1887, its purpose is to promote the development and practice of astronomy.

Baillaud was active in time standardisation, becoming the founding president of the International Time Bureau and initiating the transmission of a time signal from the Eiffel Tower. Baillaud maintained the observatory and the time signal throughout World War I, even though the German howitzer Big Bertha was targeted on the nominal co-ordinates of Paris, the location of the observatory! Baillaud's concern for the astronomical time standard led him to be an outspoken opponent of daylight saving time.

Baillaud became founding president of the International Astronomical Union in 1919 and served in this position until 1922. He retired as director of the Paris Observatory in 1926.

He was a regular academician in the astronomy section of the Académie des Sciences. [3] He won the Bruce Medal in 1923.

The crater Baillaud on the Moon is named after him, and so are asteroids 11764 Benbaillaud and 1280 Baillauda.

Bibliography [4]

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  1. Hockey, Thomas (2009). The Biographical Encyclopedia of Astronomers. Springer Publishing. ISBN   978-0-387-31022-0 . Retrieved August 22, 2012.
  2. Bulletin de la Société astronomique de France, 1911, vol. 25, pp. 581-586
  3. Archibald, R. C. (1910). "Notes on the institut de France and the annual meeting of the Académie des Sciences" (PDF). Bull. Amer. Math. Soc. 16 (6): 328–332. doi:10.1090/s0002-9904-1910-01923-6.
  4. Biblioagraphy on Googlebooks
  5. Annales de la faculté de sciences de Toulouse (1888)
  6. Texte disponible en pdf