Paris Observatory

Coordinates: 48°50′11.18″N 2°20′11.42″E / 48.8364389°N 2.3365056°E / 48.8364389; 2.3365056

Paris Observatory

The Paris Observatory (in French, Observatoire de Paris or Observatoire de Paris-Meudon) is the foremost astronomical observatory of France, and one of the largest astronomical centres in the world. Its historic main building is to be found on the Left Bank of the Seine in central Paris.

Constitution

Meridian Room (or Cassini Room) at the Paris Observatory. The Paris Meridian is traced on the floor.

Administratively, it is a grand établissement of the French Ministry of National Education, with a status close to that of a public university. Its missions include:^[1]

• research in astronomy and astrophysics;
• education (four graduate programs, Ph.D. studies);
• diffusion of knowledge to the public.

It maintains a solar observatory at Meudon (48°48′18.32″N 2°13′51.61″E / 48.8050889°N 2.2310028°E / 48.8050889; 2.2310028) and a radio astronomy observatory at Nançay.^[1] It was also the home to the International Time Bureau until its dissolution in 1987.^[2]

History

The observatory in the beginning of the eighteenth century with the wooden "Marly Tower" on the right, moved to the grounds by Giovanni Cassini, for the mounting of long tubed telescopes and even longer tubeless aerial telescopes.

Its foundation lies in the ambitions of Jean-Baptiste Colbert to extend France's maritime power and international trade in the 17th century. Louis XIV promoted its construction starting in 1667,^[3] and it being completed in 1671. It thus predates the Royal Greenwich Observatory in England which was founded in 1675. The architect of the Paris Observatory was Claude Perrault whose brother, Charles, was secretary to Colbert and superintendent of public works.^[4] Optical instruments were supplied by Giuseppe Campani. The buildings were extended in 1730, 1810, 1834, 1850, and 1951.^[3] The last extension incorporates the spectacular Meridian Room designed by Jean Prouvé.^[5]

The world's first national almanac, the Connaissance des temps was published by the observatory in 1679, using eclipses in Jupiter's satellites to aid sea-fairers in establishing longitude. In 1863, the observatory published the first modern weather maps. In 1882, a 33 cm astrographic lens was constructed, an instrument that catalysed what proved to be the over-ambitious, international Carte du Ciel project.^{[citation needed]}

In November 1913, the Paris Observatory, using the Eiffel Tower as an antenna, exchanged sustained wireless (radio) signals with the United States Naval Observatory to determine the exact difference of longitude between the two institutions.^[6]

Meudon 33-inch Great Refractor

The Meudon great refractor (Meudon 33-inch) was a 83 cm (32.6 inch) aperture refractor, which with September 20, 1909 observations by E.M. Antoniadi helped disprove the Mars canals theory.^[7] It was a double telescope completed in 1891, with secondary having 62 cm aperture lens for photography. It was one of the largest active telescopes in Europe. (see also List of largest optical refracting telescopes, and Paris Inch)

Directors

Giovanni Cassini (1671–1712) Jacques Cassini (1712–1756) César-François Cassini de Thury (1756–1784) Dominique, comte de Cassini (1784–1793) Joseph Jérôme Lefrançais de Lalande (1795–1800) Pierre Méchain (1800–1804) Jean Baptiste Joseph Delambre (1804–1822) Alexis Bouvard (1822–1843) François Arago (1843–1853) Urbain Le Verrier (1854–1870) Charles-Eugène Delaunay (1870–1873) Urbain Le Verrier (1873–1877) Amédée Mouchez (1878–1892)

Félix Tisserand (1892–1896) Maurice Loewy (1896–1907) Benjamin Baillaud (1908–1926) Henri-Alexandre Deslandres (1926–1929) Ernest Esclangon (1929–1944) André Danjon (1945–1963) Jean-François Denisse (1963–1967) Jean Delhaye (1967–1971) Raymond Michard (1971–1976) Jacques Boulon (1976–1981) Pierre Charvin (1981–1991) Michel Combes (1991–1999) Pierre Couturier (1999–2003) Daniel Egret (2003-2011) Claude Catala (2011-)

Facilities

Paris

Meudon

Solar Observatory Tower

• Solar Observatory Tower Meudon
• Chateau de Meudon
• LESIA space and astrophysics instrumentation research laboratory^[8]

Nançay

Saint-Véran

Also known as the Observatoire du Pic de Château Renard, the Observatoire de Saint-Véran was built in 1974 on top of the Pic de Château Renard (2900 m), on the commune of Saint-Véran in the Haut Queyras (Hautes Alpes département). A coronograph was in operation there for ten years; the dome was moved there from the Perrault building of the Observatoire de Paris.^{[citation needed]}

Nowadays, the AstroQueyras amateur astronomy association operates the facility, using a 60 cm telescope on loan from the Observatoire de Haute Provence. Numerous asteroids have been discovered there.^[9]

References

1. ^ ^{a b} "The Paris Observatory". l'Observatoire de Paris. http://www.obspm.fr/presentation.en.shtml. Retrieved 2007-08-27. 
2. ^ Guinot (2000)
3. ^ ^{a b} [Anon.] (2001) "Paris Observatory", Encyclopaedia Britannica, Deluxe CDROM edition
4. ^ [Anon.] (2001) "Perrault, Claude", Encyclopaedia Britannica, Deluxe CDROM edition
5. ^ [Anon.] (2001) "Prouvé, Jean", Encyclopaedia Britannica, Deluxe CDROM edition
6. ^ "Paris Time By Wireless," New York Times, Nov 22, 1913, pg 1.
7. ^ http://wwwusr2.obspm.fr/~biver/IWCMO/iwcmo_firstann.txt
8. ^ "Completion and delivery of equipment bay and camera to CNES mark major project milestone" (Press release). Released jointly by Observatoire de Paris, CNES and CNRS-INSU. 2005-06-30. http://www.cnes.fr/web/3820-pr52-2005-joint-press-release-corot-observation-satellite-cnes-mission-completion-and-delivery-of-equipment-bay-and-camera-to-cnes-mark-major-pr.php. Retrieved 2008-08-03. 
9. ^ "L'Observatoire du Pic de Château Renard (2900 m)" (in French). Histoire. l'Observatoire de Paris. http://www.obspm.fr/histoire/saintveran/saintveran.fr.shtml. Retrieved 2007-08-27. 

Bibliography

• [Anon.] (2001) "Paris Observatory", Encyclopaedia Britannica, Deluxe CDROM edition
• Aubin, D. (2003). "The fading star of the Paris Observatory in the nineteenth century: astronomers' urban culture of circulation and observation". Osiris 18: 79–100. doi:10.1086/649378.  [1]

• Guinot, B. (2000). "History of the Bureau International de l'Heure". Polar Motion: Historical and Scientific problems. pp. 175–184. http://adsabs.harvard.edu/abs/2000ASPC..208..175G. 

External links

• The Paris Observatory (official site, in English)
• History at official site
• location in Paris