Besançon Astronomical Observatory
Encyclopedia
The Observatoire des sciences de l'Univers de Besançon (Observatoire de Besançon for short, Besançon Astronomical Observatory or Besançon Observatory in English) is an astronomical
observatory
owned and operated by the Centre national de la recherche scientifique
(CNRS, National Center for Scientific Research). It is located in Besançon
, France
.
In the past, the Besançon Observatory participated in assessing and rating Swiss timepiece movements for accuracy. As marine navigation adopted the usage of mechanical timepieces for navigational aid, the accuracy of such timepieces became more critical. From this need developed an accuracy testing regime involving various astronomical observatories. In Europe
, the Neuchatel Observatory
, Geneva Observatory Besançon Observatory and Kew Observatory
were examples of prominent observatories that tested timepiece movements for accuracy. The testing process lasted for many days, typically 45 days. Each movement was tested in 5 positions and 2 temperatures, in 10 series of 4 or 5 days each. The tolerances for error were much finer than any other standard, including the modern COSC
standard. Movements that passed the stringent tests were issued a certification from the observatory called a Bulletin de Marche, signed by the Directeur of the Observatory. The Bulletin de Marche stated the testing criteria, and the actual performance of the movement. A movement with a Bulletin de Marche from an observatory became known as an Observatory Chronometer
, and such were issued a chronometer reference number by the Observatory.
The role of the observatories in assessing the accuracy of mechanical timepieces was instrumental in driving the mechanical watchmaking industry toward higher and higher levels of accuracy. As a result, today high quality mechanical watch movements have an extremely high degree of accuracy. However, no mechanical movement could ultimately compare to the accuracy of the quartz movements being developed. Accordingly, such chronometer certification ceased in the late 1960s and early 1970s with the advent of the quartz watch movement.
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
observatory
Observatory
An observatory is a location used for observing terrestrial or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed...
owned and operated by the Centre national de la recherche scientifique
Centre national de la recherche scientifique
The National Center of Scientific Research is the largest governmental research organization in France and the largest fundamental science agency in Europe....
(CNRS, National Center for Scientific Research). It is located in Besançon
Besançon
Besançon , is the capital and principal city of the Franche-Comté region in eastern France. It had a population of about 237,000 inhabitants in the metropolitan area in 2008...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
.
In the past, the Besançon Observatory participated in assessing and rating Swiss timepiece movements for accuracy. As marine navigation adopted the usage of mechanical timepieces for navigational aid, the accuracy of such timepieces became more critical. From this need developed an accuracy testing regime involving various astronomical observatories. In Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, the Neuchatel Observatory
Neuchâtel Observatory
The Observatoire Cantonal de Neuchâtel is an astronomical observatory funded by the Public Economy Department of the Neuchâtel State . It is located in Neuchâtel and was founded in 1858. Besides astronomical observations, the Neuchâtel observatory also works with atomic clocks...
, Geneva Observatory Besançon Observatory and Kew Observatory
Kew Observatory
Kew Observatory was an astronomical and terrestrial magnetic observatoryfounded by King George III , located within the Old Deer Park of the former Richmond Palace in Richmond, Surrey, now within Greater London. The former royal manor of Kew lies to the immediate north...
were examples of prominent observatories that tested timepiece movements for accuracy. The testing process lasted for many days, typically 45 days. Each movement was tested in 5 positions and 2 temperatures, in 10 series of 4 or 5 days each. The tolerances for error were much finer than any other standard, including the modern COSC
COSC
COSC aka C.O.S.C. is Contrôle Officiel Suisse des Chronomètres, the Official Swiss Chronometer Testing Institute, which is the institute responsible for certifying the accuracy and precision of wristwatches in Switzerland.-Background:...
standard. Movements that passed the stringent tests were issued a certification from the observatory called a Bulletin de Marche, signed by the Directeur of the Observatory. The Bulletin de Marche stated the testing criteria, and the actual performance of the movement. A movement with a Bulletin de Marche from an observatory became known as an Observatory Chronometer
Observatory Chronometer
In the world of mechanical timepieces, accuracy is paramount. In the times before electronics, mechanical timepieces called marine chronometers were developed to a very high degree of accuracy and used for maritime navigation...
, and such were issued a chronometer reference number by the Observatory.
The role of the observatories in assessing the accuracy of mechanical timepieces was instrumental in driving the mechanical watchmaking industry toward higher and higher levels of accuracy. As a result, today high quality mechanical watch movements have an extremely high degree of accuracy. However, no mechanical movement could ultimately compare to the accuracy of the quartz movements being developed. Accordingly, such chronometer certification ceased in the late 1960s and early 1970s with the advent of the quartz watch movement.